FFmpeg/libavcodec/h264.c

/*
 * H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
 * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file libavcodec/h264.c
 * H.264 / AVC / MPEG4 part10 codec.
 * @author Michael Niedermayer <michaelni@gmx.at>
 */

#include "internal.h"
#include "dsputil.h"
#include "avcodec.h"
#include "mpegvideo.h"
#include "h264.h"
#include "h264data.h"
#include "h264_mvpred.h"
#include "h264_parser.h"
#include "golomb.h"
#include "mathops.h"
#include "rectangle.h"
#include "vdpau_internal.h"

#include "cabac.h"
#if ARCH_X86
#include "x86/h264_i386.h"
#endif

//#undef NDEBUG
#include <assert.h>

static void svq3_luma_dc_dequant_idct_c(DCTELEM *block, int qp);
static void svq3_add_idct_c(uint8_t *dst, DCTELEM *block, int stride, int qp, int dc);

static const uint8_t rem6[52]={
0, 1, 2, 3, 4, 5, 0, 1, 2, 3, 4, 5, 0, 1, 2, 3, 4, 5, 0, 1, 2, 3, 4, 5, 0, 1, 2, 3, 4, 5, 0, 1, 2, 3, 4, 5, 0, 1, 2, 3, 4, 5, 0, 1, 2, 3, 4, 5, 0, 1, 2, 3,
};

static const uint8_t div6[52]={
0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8,
};

void ff_h264_write_back_intra_pred_mode(H264Context *h){
    const int mb_xy= h->mb_xy;

    h->intra4x4_pred_mode[mb_xy][0]= h->intra4x4_pred_mode_cache[7+8*1];
    h->intra4x4_pred_mode[mb_xy][1]= h->intra4x4_pred_mode_cache[7+8*2];
    h->intra4x4_pred_mode[mb_xy][2]= h->intra4x4_pred_mode_cache[7+8*3];
    h->intra4x4_pred_mode[mb_xy][3]= h->intra4x4_pred_mode_cache[7+8*4];
    h->intra4x4_pred_mode[mb_xy][4]= h->intra4x4_pred_mode_cache[4+8*4];
    h->intra4x4_pred_mode[mb_xy][5]= h->intra4x4_pred_mode_cache[5+8*4];
    h->intra4x4_pred_mode[mb_xy][6]= h->intra4x4_pred_mode_cache[6+8*4];
}

/**
 * checks if the top & left blocks are available if needed & changes the dc mode so it only uses the available blocks.
 */
int ff_h264_check_intra4x4_pred_mode(H264Context *h){
    MpegEncContext * const s = &h->s;
    static const int8_t top [12]= {-1, 0,LEFT_DC_PRED,-1,-1,-1,-1,-1, 0};
    static const int8_t left[12]= { 0,-1, TOP_DC_PRED, 0,-1,-1,-1, 0,-1,DC_128_PRED};
    int i;

    if(!(h->top_samples_available&0x8000)){
        for(i=0; i<4; i++){
            int status= top[ h->intra4x4_pred_mode_cache[scan8[0] + i] ];
            if(status<0){
                av_log(h->s.avctx, AV_LOG_ERROR, "top block unavailable for requested intra4x4 mode %d at %d %d\n", status, s->mb_x, s->mb_y);
                return -1;
            } else if(status){
                h->intra4x4_pred_mode_cache[scan8[0] + i]= status;
            }
        }
    }

    if((h->left_samples_available&0x8888)!=0x8888){
        static const int mask[4]={0x8000,0x2000,0x80,0x20};
        for(i=0; i<4; i++){
            if(!(h->left_samples_available&mask[i])){
                int status= left[ h->intra4x4_pred_mode_cache[scan8[0] + 8*i] ];
                if(status<0){
                    av_log(h->s.avctx, AV_LOG_ERROR, "left block unavailable for requested intra4x4 mode %d at %d %d\n", status, s->mb_x, s->mb_y);
                    return -1;
                } else if(status){
                    h->intra4x4_pred_mode_cache[scan8[0] + 8*i]= status;
                }
            }
        }
    }

    return 0;
} //FIXME cleanup like ff_h264_check_intra_pred_mode

/**
 * checks if the top & left blocks are available if needed & changes the dc mode so it only uses the available blocks.
 */
int ff_h264_check_intra_pred_mode(H264Context *h, int mode){
    MpegEncContext * const s = &h->s;
    static const int8_t top [7]= {LEFT_DC_PRED8x8, 1,-1,-1};
    static const int8_t left[7]= { TOP_DC_PRED8x8,-1, 2,-1,DC_128_PRED8x8};

    if(mode > 6U) {
        av_log(h->s.avctx, AV_LOG_ERROR, "out of range intra chroma pred mode at %d %d\n", s->mb_x, s->mb_y);
        return -1;
    }

    if(!(h->top_samples_available&0x8000)){
        mode= top[ mode ];
        if(mode<0){
            av_log(h->s.avctx, AV_LOG_ERROR, "top block unavailable for requested intra mode at %d %d\n", s->mb_x, s->mb_y);
            return -1;
        }
    }

    if((h->left_samples_available&0x8080) != 0x8080){
        mode= left[ mode ];
        if(h->left_samples_available&0x8080){ //mad cow disease mode, aka MBAFF + constrained_intra_pred
            mode= ALZHEIMER_DC_L0T_PRED8x8 + (!(h->left_samples_available&0x8000)) + 2*(mode == DC_128_PRED8x8);
        }
        if(mode<0){
            av_log(h->s.avctx, AV_LOG_ERROR, "left block unavailable for requested intra mode at %d %d\n", s->mb_x, s->mb_y);
            return -1;
        }
    }

    return mode;
}

const uint8_t *ff_h264_decode_nal(H264Context *h, const uint8_t *src, int *dst_length, int *consumed, int length){
    int i, si, di;
    uint8_t *dst;
    int bufidx;

//    src[0]&0x80;                //forbidden bit
    h->nal_ref_idc= src[0]>>5;
    h->nal_unit_type= src[0]&0x1F;

    src++; length--;
#if 0
    for(i=0; i<length; i++)
        printf("%2X ", src[i]);
#endif

#if HAVE_FAST_UNALIGNED
# if HAVE_FAST_64BIT
#   define RS 7
    for(i=0; i+1<length; i+=9){
        if(!((~*(const uint64_t*)(src+i) & (*(const uint64_t*)(src+i) - 0x0100010001000101ULL)) & 0x8000800080008080ULL))
# else
#   define RS 3
    for(i=0; i+1<length; i+=5){
        if(!((~*(const uint32_t*)(src+i) & (*(const uint32_t*)(src+i) - 0x01000101U)) & 0x80008080U))
# endif
            continue;
        if(i>0 && !src[i]) i--;
        while(src[i]) i++;
#else
#   define RS 0
    for(i=0; i+1<length; i+=2){
        if(src[i]) continue;
        if(i>0 && src[i-1]==0) i--;
#endif
        if(i+2<length && src[i+1]==0 && src[i+2]<=3){
            if(src[i+2]!=3){
                /* startcode, so we must be past the end */
                length=i;
            }
            break;
        }
        i-= RS;
    }

    if(i>=length-1){ //no escaped 0
        *dst_length= length;
        *consumed= length+1; //+1 for the header
        return src;
    }

    bufidx = h->nal_unit_type == NAL_DPC ? 1 : 0; // use second escape buffer for inter data
    av_fast_malloc(&h->rbsp_buffer[bufidx], &h->rbsp_buffer_size[bufidx], length+FF_INPUT_BUFFER_PADDING_SIZE);
    dst= h->rbsp_buffer[bufidx];

    if (dst == NULL){
        return NULL;
    }

//printf("decoding esc\n");
    memcpy(dst, src, i);
    si=di=i;
    while(si+2<length){
        //remove escapes (very rare 1:2^22)
        if(src[si+2]>3){
            dst[di++]= src[si++];
            dst[di++]= src[si++];
        }else if(src[si]==0 && src[si+1]==0){
            if(src[si+2]==3){ //escape
                dst[di++]= 0;
                dst[di++]= 0;
                si+=3;
                continue;
            }else //next start code
                goto nsc;
        }

        dst[di++]= src[si++];
    }
    while(si<length)
        dst[di++]= src[si++];
nsc:

    memset(dst+di, 0, FF_INPUT_BUFFER_PADDING_SIZE);

    *dst_length= di;
    *consumed= si + 1;//+1 for the header
//FIXME store exact number of bits in the getbitcontext (it is needed for decoding)
    return dst;
}

int ff_h264_decode_rbsp_trailing(H264Context *h, const uint8_t *src){
    int v= *src;
    int r;

    tprintf(h->s.avctx, "rbsp trailing %X\n", v);

    for(r=1; r<9; r++){
        if(v&1) return r;
        v>>=1;
    }
    return 0;
}

/**
 * IDCT transforms the 16 dc values and dequantizes them.
 * @param qp quantization parameter
 */
static void h264_luma_dc_dequant_idct_c(DCTELEM *block, int qp, int qmul){
#define stride 16
    int i;
    int temp[16]; //FIXME check if this is a good idea
    static const int x_offset[4]={0, 1*stride, 4* stride,  5*stride};
    static const int y_offset[4]={0, 2*stride, 8* stride, 10*stride};

//memset(block, 64, 2*256);
//return;
    for(i=0; i<4; i++){
        const int offset= y_offset[i];
        const int z0= block[offset+stride*0] + block[offset+stride*4];
        const int z1= block[offset+stride*0] - block[offset+stride*4];
        const int z2= block[offset+stride*1] - block[offset+stride*5];
        const int z3= block[offset+stride*1] + block[offset+stride*5];

        temp[4*i+0]= z0+z3;
        temp[4*i+1]= z1+z2;
        temp[4*i+2]= z1-z2;
        temp[4*i+3]= z0-z3;
    }

    for(i=0; i<4; i++){
        const int offset= x_offset[i];
        const int z0= temp[4*0+i] + temp[4*2+i];
        const int z1= temp[4*0+i] - temp[4*2+i];
        const int z2= temp[4*1+i] - temp[4*3+i];
        const int z3= temp[4*1+i] + temp[4*3+i];

        block[stride*0 +offset]= ((((z0 + z3)*qmul + 128 ) >> 8)); //FIXME think about merging this into decode_residual
        block[stride*2 +offset]= ((((z1 + z2)*qmul + 128 ) >> 8));
        block[stride*8 +offset]= ((((z1 - z2)*qmul + 128 ) >> 8));
        block[stride*10+offset]= ((((z0 - z3)*qmul + 128 ) >> 8));
    }
}

#if 0
/**
 * DCT transforms the 16 dc values.
 * @param qp quantization parameter ??? FIXME
 */
static void h264_luma_dc_dct_c(DCTELEM *block/*, int qp*/){
//    const int qmul= dequant_coeff[qp][0];
    int i;
    int temp[16]; //FIXME check if this is a good idea
    static const int x_offset[4]={0, 1*stride, 4* stride,  5*stride};
    static const int y_offset[4]={0, 2*stride, 8* stride, 10*stride};

    for(i=0; i<4; i++){
        const int offset= y_offset[i];
        const int z0= block[offset+stride*0] + block[offset+stride*4];
        const int z1= block[offset+stride*0] - block[offset+stride*4];
        const int z2= block[offset+stride*1] - block[offset+stride*5];
        const int z3= block[offset+stride*1] + block[offset+stride*5];

        temp[4*i+0]= z0+z3;
        temp[4*i+1]= z1+z2;
        temp[4*i+2]= z1-z2;
        temp[4*i+3]= z0-z3;
    }

    for(i=0; i<4; i++){
        const int offset= x_offset[i];
        const int z0= temp[4*0+i] + temp[4*2+i];
        const int z1= temp[4*0+i] - temp[4*2+i];
        const int z2= temp[4*1+i] - temp[4*3+i];
        const int z3= temp[4*1+i] + temp[4*3+i];

        block[stride*0 +offset]= (z0 + z3)>>1;
        block[stride*2 +offset]= (z1 + z2)>>1;
        block[stride*8 +offset]= (z1 - z2)>>1;
        block[stride*10+offset]= (z0 - z3)>>1;
    }
}
#endif

#undef xStride
#undef stride

static void chroma_dc_dequant_idct_c(DCTELEM *block, int qp, int qmul){
    const int stride= 16*2;
    const int xStride= 16;
    int a,b,c,d,e;

    a= block[stride*0 + xStride*0];
    b= block[stride*0 + xStride*1];
    c= block[stride*1 + xStride*0];
    d= block[stride*1 + xStride*1];

    e= a-b;
    a= a+b;
    b= c-d;
    c= c+d;

    block[stride*0 + xStride*0]= ((a+c)*qmul) >> 7;
    block[stride*0 + xStride*1]= ((e+b)*qmul) >> 7;
    block[stride*1 + xStride*0]= ((a-c)*qmul) >> 7;
    block[stride*1 + xStride*1]= ((e-b)*qmul) >> 7;
}

#if 0
static void chroma_dc_dct_c(DCTELEM *block){
    const int stride= 16*2;
    const int xStride= 16;
    int a,b,c,d,e;

    a= block[stride*0 + xStride*0];
    b= block[stride*0 + xStride*1];
    c= block[stride*1 + xStride*0];
    d= block[stride*1 + xStride*1];

    e= a-b;
    a= a+b;
    b= c-d;
    c= c+d;

    block[stride*0 + xStride*0]= (a+c);
    block[stride*0 + xStride*1]= (e+b);
    block[stride*1 + xStride*0]= (a-c);
    block[stride*1 + xStride*1]= (e-b);
}
#endif

static inline void mc_dir_part(H264Context *h, Picture *pic, int n, int square, int chroma_height, int delta, int list,
                           uint8_t *dest_y, uint8_t *dest_cb, uint8_t *dest_cr,
                           int src_x_offset, int src_y_offset,
                           qpel_mc_func *qpix_op, h264_chroma_mc_func chroma_op){
    MpegEncContext * const s = &h->s;
    const int mx= h->mv_cache[list][ scan8[n] ][0] + src_x_offset*8;
    int my=       h->mv_cache[list][ scan8[n] ][1] + src_y_offset*8;
    const int luma_xy= (mx&3) + ((my&3)<<2);
    uint8_t * src_y = pic->data[0] + (mx>>2) + (my>>2)*h->mb_linesize;
    uint8_t * src_cb, * src_cr;
    int extra_width= h->emu_edge_width;
    int extra_height= h->emu_edge_height;
    int emu=0;
    const int full_mx= mx>>2;
    const int full_my= my>>2;
    const int pic_width  = 16*s->mb_width;
    const int pic_height = 16*s->mb_height >> MB_FIELD;

    if(mx&7) extra_width -= 3;
    if(my&7) extra_height -= 3;

    if(   full_mx < 0-extra_width
       || full_my < 0-extra_height
       || full_mx + 16/*FIXME*/ > pic_width + extra_width
       || full_my + 16/*FIXME*/ > pic_height + extra_height){
        ff_emulated_edge_mc(s->edge_emu_buffer, src_y - 2 - 2*h->mb_linesize, h->mb_linesize, 16+5, 16+5/*FIXME*/, full_mx-2, full_my-2, pic_width, pic_height);
            src_y= s->edge_emu_buffer + 2 + 2*h->mb_linesize;
        emu=1;
    }

    qpix_op[luma_xy](dest_y, src_y, h->mb_linesize); //FIXME try variable height perhaps?
    if(!square){
        qpix_op[luma_xy](dest_y + delta, src_y + delta, h->mb_linesize);
    }

    if(CONFIG_GRAY && s->flags&CODEC_FLAG_GRAY) return;

    if(MB_FIELD){
        // chroma offset when predicting from a field of opposite parity
        my += 2 * ((s->mb_y & 1) - (pic->reference - 1));
        emu |= (my>>3) < 0 || (my>>3) + 8 >= (pic_height>>1);
    }
    src_cb= pic->data[1] + (mx>>3) + (my>>3)*h->mb_uvlinesize;
    src_cr= pic->data[2] + (mx>>3) + (my>>3)*h->mb_uvlinesize;

    if(emu){
        ff_emulated_edge_mc(s->edge_emu_buffer, src_cb, h->mb_uvlinesize, 9, 9/*FIXME*/, (mx>>3), (my>>3), pic_width>>1, pic_height>>1);
            src_cb= s->edge_emu_buffer;
    }
    chroma_op(dest_cb, src_cb, h->mb_uvlinesize, chroma_height, mx&7, my&7);

    if(emu){
        ff_emulated_edge_mc(s->edge_emu_buffer, src_cr, h->mb_uvlinesize, 9, 9/*FIXME*/, (mx>>3), (my>>3), pic_width>>1, pic_height>>1);
            src_cr= s->edge_emu_buffer;
    }
    chroma_op(dest_cr, src_cr, h->mb_uvlinesize, chroma_height, mx&7, my&7);
}

static inline void mc_part_std(H264Context *h, int n, int square, int chroma_height, int delta,
                           uint8_t *dest_y, uint8_t *dest_cb, uint8_t *dest_cr,
                           int x_offset, int y_offset,
                           qpel_mc_func *qpix_put, h264_chroma_mc_func chroma_put,
                           qpel_mc_func *qpix_avg, h264_chroma_mc_func chroma_avg,
                           int list0, int list1){
    MpegEncContext * const s = &h->s;
    qpel_mc_func *qpix_op=  qpix_put;
    h264_chroma_mc_func chroma_op= chroma_put;

    dest_y  += 2*x_offset + 2*y_offset*h->  mb_linesize;
    dest_cb +=   x_offset +   y_offset*h->mb_uvlinesize;
    dest_cr +=   x_offset +   y_offset*h->mb_uvlinesize;
    x_offset += 8*s->mb_x;
    y_offset += 8*(s->mb_y >> MB_FIELD);

    if(list0){
        Picture *ref= &h->ref_list[0][ h->ref_cache[0][ scan8[n] ] ];
        mc_dir_part(h, ref, n, square, chroma_height, delta, 0,
                           dest_y, dest_cb, dest_cr, x_offset, y_offset,
                           qpix_op, chroma_op);

        qpix_op=  qpix_avg;
        chroma_op= chroma_avg;
    }

    if(list1){
        Picture *ref= &h->ref_list[1][ h->ref_cache[1][ scan8[n] ] ];
        mc_dir_part(h, ref, n, square, chroma_height, delta, 1,
                           dest_y, dest_cb, dest_cr, x_offset, y_offset,
                           qpix_op, chroma_op);
    }
}

static inline void mc_part_weighted(H264Context *h, int n, int square, int chroma_height, int delta,
                           uint8_t *dest_y, uint8_t *dest_cb, uint8_t *dest_cr,
                           int x_offset, int y_offset,
                           qpel_mc_func *qpix_put, h264_chroma_mc_func chroma_put,
                           h264_weight_func luma_weight_op, h264_weight_func chroma_weight_op,
                           h264_biweight_func luma_weight_avg, h264_biweight_func chroma_weight_avg,
                           int list0, int list1){
    MpegEncContext * const s = &h->s;

    dest_y  += 2*x_offset + 2*y_offset*h->  mb_linesize;
    dest_cb +=   x_offset +   y_offset*h->mb_uvlinesize;
    dest_cr +=   x_offset +   y_offset*h->mb_uvlinesize;
    x_offset += 8*s->mb_x;
    y_offset += 8*(s->mb_y >> MB_FIELD);

    if(list0 && list1){
        /* don't optimize for luma-only case, since B-frames usually
         * use implicit weights => chroma too. */
        uint8_t *tmp_cb = s->obmc_scratchpad;
        uint8_t *tmp_cr = s->obmc_scratchpad + 8;
        uint8_t *tmp_y  = s->obmc_scratchpad + 8*h->mb_uvlinesize;
        int refn0 = h->ref_cache[0][ scan8[n] ];
        int refn1 = h->ref_cache[1][ scan8[n] ];

        mc_dir_part(h, &h->ref_list[0][refn0], n, square, chroma_height, delta, 0,
                    dest_y, dest_cb, dest_cr,
                    x_offset, y_offset, qpix_put, chroma_put);
        mc_dir_part(h, &h->ref_list[1][refn1], n, square, chroma_height, delta, 1,
                    tmp_y, tmp_cb, tmp_cr,
                    x_offset, y_offset, qpix_put, chroma_put);

        if(h->use_weight == 2){
            int weight0 = h->implicit_weight[refn0][refn1];
            int weight1 = 64 - weight0;
            luma_weight_avg(  dest_y,  tmp_y,  h->  mb_linesize, 5, weight0, weight1, 0);
            chroma_weight_avg(dest_cb, tmp_cb, h->mb_uvlinesize, 5, weight0, weight1, 0);
            chroma_weight_avg(dest_cr, tmp_cr, h->mb_uvlinesize, 5, weight0, weight1, 0);
        }else{
            luma_weight_avg(dest_y, tmp_y, h->mb_linesize, h->luma_log2_weight_denom,
                            h->luma_weight[0][refn0], h->luma_weight[1][refn1],
                            h->luma_offset[0][refn0] + h->luma_offset[1][refn1]);
            chroma_weight_avg(dest_cb, tmp_cb, h->mb_uvlinesize, h->chroma_log2_weight_denom,
                            h->chroma_weight[0][refn0][0], h->chroma_weight[1][refn1][0],
                            h->chroma_offset[0][refn0][0] + h->chroma_offset[1][refn1][0]);
            chroma_weight_avg(dest_cr, tmp_cr, h->mb_uvlinesize, h->chroma_log2_weight_denom,
                            h->chroma_weight[0][refn0][1], h->chroma_weight[1][refn1][1],
                            h->chroma_offset[0][refn0][1] + h->chroma_offset[1][refn1][1]);
        }
    }else{
        int list = list1 ? 1 : 0;
        int refn = h->ref_cache[list][ scan8[n] ];
        Picture *ref= &h->ref_list[list][refn];
        mc_dir_part(h, ref, n, square, chroma_height, delta, list,
                    dest_y, dest_cb, dest_cr, x_offset, y_offset,
                    qpix_put, chroma_put);

        luma_weight_op(dest_y, h->mb_linesize, h->luma_log2_weight_denom,
                       h->luma_weight[list][refn], h->luma_offset[list][refn]);
        if(h->use_weight_chroma){
            chroma_weight_op(dest_cb, h->mb_uvlinesize, h->chroma_log2_weight_denom,
                             h->chroma_weight[list][refn][0], h->chroma_offset[list][refn][0]);
            chroma_weight_op(dest_cr, h->mb_uvlinesize, h->chroma_log2_weight_denom,
                             h->chroma_weight[list][refn][1], h->chroma_offset[list][refn][1]);
        }
    }
}

static inline void mc_part(H264Context *h, int n, int square, int chroma_height, int delta,
                           uint8_t *dest_y, uint8_t *dest_cb, uint8_t *dest_cr,
                           int x_offset, int y_offset,
                           qpel_mc_func *qpix_put, h264_chroma_mc_func chroma_put,
                           qpel_mc_func *qpix_avg, h264_chroma_mc_func chroma_avg,
                           h264_weight_func *weight_op, h264_biweight_func *weight_avg,
                           int list0, int list1){
    if((h->use_weight==2 && list0 && list1
        && (h->implicit_weight[ h->ref_cache[0][scan8[n]] ][ h->ref_cache[1][scan8[n]] ] != 32))
       || h->use_weight==1)
        mc_part_weighted(h, n, square, chroma_height, delta, dest_y, dest_cb, dest_cr,
                         x_offset, y_offset, qpix_put, chroma_put,
                         weight_op[0], weight_op[3], weight_avg[0], weight_avg[3], list0, list1);
    else
        mc_part_std(h, n, square, chroma_height, delta, dest_y, dest_cb, dest_cr,
                    x_offset, y_offset, qpix_put, chroma_put, qpix_avg, chroma_avg, list0, list1);
}

static inline void prefetch_motion(H264Context *h, int list){
    /* fetch pixels for estimated mv 4 macroblocks ahead
     * optimized for 64byte cache lines */
    MpegEncContext * const s = &h->s;
    const int refn = h->ref_cache[list][scan8[0]];
    if(refn >= 0){
        const int mx= (h->mv_cache[list][scan8[0]][0]>>2) + 16*s->mb_x + 8;
        const int my= (h->mv_cache[list][scan8[0]][1]>>2) + 16*s->mb_y;
        uint8_t **src= h->ref_list[list][refn].data;
        int off= mx + (my + (s->mb_x&3)*4)*h->mb_linesize + 64;
        s->dsp.prefetch(src[0]+off, s->linesize, 4);
        off= (mx>>1) + ((my>>1) + (s->mb_x&7))*s->uvlinesize + 64;
        s->dsp.prefetch(src[1]+off, src[2]-src[1], 2);
    }
}

static void hl_motion(H264Context *h, uint8_t *dest_y, uint8_t *dest_cb, uint8_t *dest_cr,
                      qpel_mc_func (*qpix_put)[16], h264_chroma_mc_func (*chroma_put),
                      qpel_mc_func (*qpix_avg)[16], h264_chroma_mc_func (*chroma_avg),
                      h264_weight_func *weight_op, h264_biweight_func *weight_avg){
    MpegEncContext * const s = &h->s;
    const int mb_xy= h->mb_xy;
    const int mb_type= s->current_picture.mb_type[mb_xy];

    assert(IS_INTER(mb_type));

    prefetch_motion(h, 0);

    if(IS_16X16(mb_type)){
        mc_part(h, 0, 1, 8, 0, dest_y, dest_cb, dest_cr, 0, 0,
                qpix_put[0], chroma_put[0], qpix_avg[0], chroma_avg[0],
                &weight_op[0], &weight_avg[0],
                IS_DIR(mb_type, 0, 0), IS_DIR(mb_type, 0, 1));
    }else if(IS_16X8(mb_type)){
        mc_part(h, 0, 0, 4, 8, dest_y, dest_cb, dest_cr, 0, 0,
                qpix_put[1], chroma_put[0], qpix_avg[1], chroma_avg[0],
                &weight_op[1], &weight_avg[1],
                IS_DIR(mb_type, 0, 0), IS_DIR(mb_type, 0, 1));
        mc_part(h, 8, 0, 4, 8, dest_y, dest_cb, dest_cr, 0, 4,
                qpix_put[1], chroma_put[0], qpix_avg[1], chroma_avg[0],
                &weight_op[1], &weight_avg[1],
                IS_DIR(mb_type, 1, 0), IS_DIR(mb_type, 1, 1));
    }else if(IS_8X16(mb_type)){
        mc_part(h, 0, 0, 8, 8*h->mb_linesize, dest_y, dest_cb, dest_cr, 0, 0,
                qpix_put[1], chroma_put[1], qpix_avg[1], chroma_avg[1],
                &weight_op[2], &weight_avg[2],
                IS_DIR(mb_type, 0, 0), IS_DIR(mb_type, 0, 1));
        mc_part(h, 4, 0, 8, 8*h->mb_linesize, dest_y, dest_cb, dest_cr, 4, 0,
                qpix_put[1], chroma_put[1], qpix_avg[1], chroma_avg[1],
                &weight_op[2], &weight_avg[2],
                IS_DIR(mb_type, 1, 0), IS_DIR(mb_type, 1, 1));
    }else{
        int i;

        assert(IS_8X8(mb_type));

        for(i=0; i<4; i++){
            const int sub_mb_type= h->sub_mb_type[i];
            const int n= 4*i;
            int x_offset= (i&1)<<2;
            int y_offset= (i&2)<<1;

            if(IS_SUB_8X8(sub_mb_type)){
                mc_part(h, n, 1, 4, 0, dest_y, dest_cb, dest_cr, x_offset, y_offset,
                    qpix_put[1], chroma_put[1], qpix_avg[1], chroma_avg[1],
                    &weight_op[3], &weight_avg[3],
                    IS_DIR(sub_mb_type, 0, 0), IS_DIR(sub_mb_type, 0, 1));
            }else if(IS_SUB_8X4(sub_mb_type)){
                mc_part(h, n  , 0, 2, 4, dest_y, dest_cb, dest_cr, x_offset, y_offset,
                    qpix_put[2], chroma_put[1], qpix_avg[2], chroma_avg[1],
                    &weight_op[4], &weight_avg[4],
                    IS_DIR(sub_mb_type, 0, 0), IS_DIR(sub_mb_type, 0, 1));
                mc_part(h, n+2, 0, 2, 4, dest_y, dest_cb, dest_cr, x_offset, y_offset+2,
                    qpix_put[2], chroma_put[1], qpix_avg[2], chroma_avg[1],
                    &weight_op[4], &weight_avg[4],
                    IS_DIR(sub_mb_type, 0, 0), IS_DIR(sub_mb_type, 0, 1));
            }else if(IS_SUB_4X8(sub_mb_type)){
                mc_part(h, n  , 0, 4, 4*h->mb_linesize, dest_y, dest_cb, dest_cr, x_offset, y_offset,
                    qpix_put[2], chroma_put[2], qpix_avg[2], chroma_avg[2],
                    &weight_op[5], &weight_avg[5],
                    IS_DIR(sub_mb_type, 0, 0), IS_DIR(sub_mb_type, 0, 1));
                mc_part(h, n+1, 0, 4, 4*h->mb_linesize, dest_y, dest_cb, dest_cr, x_offset+2, y_offset,
                    qpix_put[2], chroma_put[2], qpix_avg[2], chroma_avg[2],
                    &weight_op[5], &weight_avg[5],
                    IS_DIR(sub_mb_type, 0, 0), IS_DIR(sub_mb_type, 0, 1));
            }else{
                int j;
                assert(IS_SUB_4X4(sub_mb_type));
                for(j=0; j<4; j++){
                    int sub_x_offset= x_offset + 2*(j&1);
                    int sub_y_offset= y_offset +   (j&2);
                    mc_part(h, n+j, 1, 2, 0, dest_y, dest_cb, dest_cr, sub_x_offset, sub_y_offset,
                        qpix_put[2], chroma_put[2], qpix_avg[2], chroma_avg[2],
                        &weight_op[6], &weight_avg[6],
                        IS_DIR(sub_mb_type, 0, 0), IS_DIR(sub_mb_type, 0, 1));
                }
            }
        }
    }

    prefetch_motion(h, 1);
}


static void free_tables(H264Context *h){
    int i;
    H264Context *hx;
    av_freep(&h->intra4x4_pred_mode);
    av_freep(&h->chroma_pred_mode_table);
    av_freep(&h->cbp_table);
    av_freep(&h->mvd_table[0]);
    av_freep(&h->mvd_table[1]);
    av_freep(&h->direct_table);
    av_freep(&h->non_zero_count);
    av_freep(&h->slice_table_base);
    h->slice_table= NULL;

    av_freep(&h->mb2b_xy);
    av_freep(&h->mb2b8_xy);

    for(i = 0; i < MAX_THREADS; i++) {
        hx = h->thread_context[i];
        if(!hx) continue;
        av_freep(&hx->top_borders[1]);
        av_freep(&hx->top_borders[0]);
        av_freep(&hx->s.obmc_scratchpad);
        av_freep(&hx->rbsp_buffer[1]);
        av_freep(&hx->rbsp_buffer[0]);
        hx->rbsp_buffer_size[0] = 0;
        hx->rbsp_buffer_size[1] = 0;
        if (i) av_freep(&h->thread_context[i]);
    }
}

static void init_dequant8_coeff_table(H264Context *h){
    int i,q,x;
    const int transpose = (h->s.dsp.h264_idct8_add != ff_h264_idct8_add_c); //FIXME ugly
    h->dequant8_coeff[0] = h->dequant8_buffer[0];
    h->dequant8_coeff[1] = h->dequant8_buffer[1];

    for(i=0; i<2; i++ ){
        if(i && !memcmp(h->pps.scaling_matrix8[0], h->pps.scaling_matrix8[1], 64*sizeof(uint8_t))){
            h->dequant8_coeff[1] = h->dequant8_buffer[0];
            break;
        }

        for(q=0; q<52; q++){
            int shift = div6[q];
            int idx = rem6[q];
            for(x=0; x<64; x++)
                h->dequant8_coeff[i][q][transpose ? (x>>3)|((x&7)<<3) : x] =
                    ((uint32_t)dequant8_coeff_init[idx][ dequant8_coeff_init_scan[((x>>1)&12) | (x&3)] ] *
                    h->pps.scaling_matrix8[i][x]) << shift;
        }
    }
}

static void init_dequant4_coeff_table(H264Context *h){
    int i,j,q,x;
    const int transpose = (h->s.dsp.h264_idct_add != ff_h264_idct_add_c); //FIXME ugly
    for(i=0; i<6; i++ ){
        h->dequant4_coeff[i] = h->dequant4_buffer[i];
        for(j=0; j<i; j++){
            if(!memcmp(h->pps.scaling_matrix4[j], h->pps.scaling_matrix4[i], 16*sizeof(uint8_t))){
                h->dequant4_coeff[i] = h->dequant4_buffer[j];
                break;
            }
        }
        if(j<i)
            continue;

        for(q=0; q<52; q++){
            int shift = div6[q] + 2;
            int idx = rem6[q];
            for(x=0; x<16; x++)
                h->dequant4_coeff[i][q][transpose ? (x>>2)|((x<<2)&0xF) : x] =
                    ((uint32_t)dequant4_coeff_init[idx][(x&1) + ((x>>2)&1)] *
                    h->pps.scaling_matrix4[i][x]) << shift;
        }
    }
}

static void init_dequant_tables(H264Context *h){
    int i,x;
    init_dequant4_coeff_table(h);
    if(h->pps.transform_8x8_mode)
        init_dequant8_coeff_table(h);
    if(h->sps.transform_bypass){
        for(i=0; i<6; i++)
            for(x=0; x<16; x++)
                h->dequant4_coeff[i][0][x] = 1<<6;
        if(h->pps.transform_8x8_mode)
            for(i=0; i<2; i++)
                for(x=0; x<64; x++)
                    h->dequant8_coeff[i][0][x] = 1<<6;
    }
}


int ff_h264_alloc_tables(H264Context *h){
    MpegEncContext * const s = &h->s;
    const int big_mb_num= s->mb_stride * (s->mb_height+1);
    int x,y;

    FF_ALLOCZ_OR_GOTO(h->s.avctx, h->intra4x4_pred_mode, big_mb_num * 8  * sizeof(uint8_t), fail)

    FF_ALLOCZ_OR_GOTO(h->s.avctx, h->non_zero_count    , big_mb_num * 16 * sizeof(uint8_t), fail)
    FF_ALLOCZ_OR_GOTO(h->s.avctx, h->slice_table_base  , (big_mb_num+s->mb_stride) * sizeof(*h->slice_table_base), fail)
    FF_ALLOCZ_OR_GOTO(h->s.avctx, h->cbp_table, big_mb_num * sizeof(uint16_t), fail)

    FF_ALLOCZ_OR_GOTO(h->s.avctx, h->chroma_pred_mode_table, big_mb_num * sizeof(uint8_t), fail)
    FF_ALLOCZ_OR_GOTO(h->s.avctx, h->mvd_table[0], 32*big_mb_num * sizeof(uint16_t), fail);
    FF_ALLOCZ_OR_GOTO(h->s.avctx, h->mvd_table[1], 32*big_mb_num * sizeof(uint16_t), fail);
    FF_ALLOCZ_OR_GOTO(h->s.avctx, h->direct_table, 32*big_mb_num * sizeof(uint8_t) , fail);

    memset(h->slice_table_base, -1, (big_mb_num+s->mb_stride)  * sizeof(*h->slice_table_base));
    h->slice_table= h->slice_table_base + s->mb_stride*2 + 1;

    FF_ALLOCZ_OR_GOTO(h->s.avctx, h->mb2b_xy  , big_mb_num * sizeof(uint32_t), fail);
    FF_ALLOCZ_OR_GOTO(h->s.avctx, h->mb2b8_xy , big_mb_num * sizeof(uint32_t), fail);
    for(y=0; y<s->mb_height; y++){
        for(x=0; x<s->mb_width; x++){
            const int mb_xy= x + y*s->mb_stride;
            const int b_xy = 4*x + 4*y*h->b_stride;
            const int b8_xy= 2*x + 2*y*h->b8_stride;

            h->mb2b_xy [mb_xy]= b_xy;
            h->mb2b8_xy[mb_xy]= b8_xy;
        }
    }

    s->obmc_scratchpad = NULL;

    if(!h->dequant4_coeff[0])
        init_dequant_tables(h);

    return 0;
fail:
    free_tables(h);
    return -1;
}

/**
 * Mimic alloc_tables(), but for every context thread.
 */
static void clone_tables(H264Context *dst, H264Context *src){
    dst->intra4x4_pred_mode       = src->intra4x4_pred_mode;
    dst->non_zero_count           = src->non_zero_count;
    dst->slice_table              = src->slice_table;
    dst->cbp_table                = src->cbp_table;
    dst->mb2b_xy                  = src->mb2b_xy;
    dst->mb2b8_xy                 = src->mb2b8_xy;
    dst->chroma_pred_mode_table   = src->chroma_pred_mode_table;
    dst->mvd_table[0]             = src->mvd_table[0];
    dst->mvd_table[1]             = src->mvd_table[1];
    dst->direct_table             = src->direct_table;

    dst->s.obmc_scratchpad = NULL;
    ff_h264_pred_init(&dst->hpc, src->s.codec_id);
}

/**
 * Init context
 * Allocate buffers which are not shared amongst multiple threads.
 */
static int context_init(H264Context *h){
    FF_ALLOCZ_OR_GOTO(h->s.avctx, h->top_borders[0], h->s.mb_width * (16+8+8) * sizeof(uint8_t), fail)
    FF_ALLOCZ_OR_GOTO(h->s.avctx, h->top_borders[1], h->s.mb_width * (16+8+8) * sizeof(uint8_t), fail)

    return 0;
fail:
    return -1; // free_tables will clean up for us
}

static av_cold void common_init(H264Context *h){
    MpegEncContext * const s = &h->s;

    s->width = s->avctx->width;
    s->height = s->avctx->height;
    s->codec_id= s->avctx->codec->id;

    ff_h264_pred_init(&h->hpc, s->codec_id);

    h->dequant_coeff_pps= -1;
    s->unrestricted_mv=1;
    s->decode=1; //FIXME

    dsputil_init(&s->dsp, s->avctx); // needed so that idct permutation is known early

    memset(h->pps.scaling_matrix4, 16, 6*16*sizeof(uint8_t));
    memset(h->pps.scaling_matrix8, 16, 2*64*sizeof(uint8_t));
}

av_cold int ff_h264_decode_init(AVCodecContext *avctx){
    H264Context *h= avctx->priv_data;
    MpegEncContext * const s = &h->s;

    MPV_decode_defaults(s);

    s->avctx = avctx;
    common_init(h);

    s->out_format = FMT_H264;
    s->workaround_bugs= avctx->workaround_bugs;

    // set defaults
//    s->decode_mb= ff_h263_decode_mb;
    s->quarter_sample = 1;
    if(!avctx->has_b_frames)
    s->low_delay= 1;

    avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;

    ff_h264_decode_init_vlc();

    if(avctx->extradata_size > 0 && avctx->extradata &&
       *(char *)avctx->extradata == 1){
        h->is_avc = 1;
        h->got_avcC = 0;
    } else {
        h->is_avc = 0;
    }

    h->thread_context[0] = h;
    h->outputed_poc = INT_MIN;
    h->prev_poc_msb= 1<<16;
    ff_h264_reset_sei(h);
    if(avctx->codec_id == CODEC_ID_H264){
        if(avctx->ticks_per_frame == 1){
            s->avctx->time_base.den *=2;
        }
        avctx->ticks_per_frame = 2;
    }
    return 0;
}

int ff_h264_frame_start(H264Context *h){
    MpegEncContext * const s = &h->s;
    int i;

    if(MPV_frame_start(s, s->avctx) < 0)
        return -1;
    ff_er_frame_start(s);
    /*
     * MPV_frame_start uses pict_type to derive key_frame.
     * This is incorrect for H.264; IDR markings must be used.
     * Zero here; IDR markings per slice in frame or fields are ORed in later.
     * See decode_nal_units().
     */
    s->current_picture_ptr->key_frame= 0;
    s->current_picture_ptr->mmco_reset= 0;

    assert(s->linesize && s->uvlinesize);

    for(i=0; i<16; i++){
        h->block_offset[i]= 4*((scan8[i] - scan8[0])&7) + 4*s->linesize*((scan8[i] - scan8[0])>>3);
        h->block_offset[24+i]= 4*((scan8[i] - scan8[0])&7) + 8*s->linesize*((scan8[i] - scan8[0])>>3);
    }
    for(i=0; i<4; i++){
        h->block_offset[16+i]=
        h->block_offset[20+i]= 4*((scan8[i] - scan8[0])&7) + 4*s->uvlinesize*((scan8[i] - scan8[0])>>3);
        h->block_offset[24+16+i]=
        h->block_offset[24+20+i]= 4*((scan8[i] - scan8[0])&7) + 8*s->uvlinesize*((scan8[i] - scan8[0])>>3);
    }

    /* can't be in alloc_tables because linesize isn't known there.
     * FIXME: redo bipred weight to not require extra buffer? */
    for(i = 0; i < s->avctx->thread_count; i++)
        if(!h->thread_context[i]->s.obmc_scratchpad)
            h->thread_context[i]->s.obmc_scratchpad = av_malloc(16*2*s->linesize + 8*2*s->uvlinesize);

    /* some macroblocks will be accessed before they're available */
    if(FRAME_MBAFF || s->avctx->thread_count > 1)
        memset(h->slice_table, -1, (s->mb_height*s->mb_stride-1) * sizeof(*h->slice_table));

//    s->decode= (s->flags&CODEC_FLAG_PSNR) || !s->encoding || s->current_picture.reference /*|| h->contains_intra*/ || 1;

    // We mark the current picture as non-reference after allocating it, so
    // that if we break out due to an error it can be released automatically
    // in the next MPV_frame_start().
    // SVQ3 as well as most other codecs have only last/next/current and thus
    // get released even with set reference, besides SVQ3 and others do not
    // mark frames as reference later "naturally".
    if(s->codec_id != CODEC_ID_SVQ3)
        s->current_picture_ptr->reference= 0;

    s->current_picture_ptr->field_poc[0]=
    s->current_picture_ptr->field_poc[1]= INT_MAX;
    assert(s->current_picture_ptr->long_ref==0);

    return 0;
}

static inline void backup_mb_border(H264Context *h, uint8_t *src_y, uint8_t *src_cb, uint8_t *src_cr, int linesize, int uvlinesize, int simple){
    MpegEncContext * const s = &h->s;
    int i;
    int step    = 1;
    int offset  = 1;
    int uvoffset= 1;
    int top_idx = 1;
    int skiplast= 0;

    src_y  -=   linesize;
    src_cb -= uvlinesize;
    src_cr -= uvlinesize;

    if(!simple && FRAME_MBAFF){
        if(s->mb_y&1){
            offset  = MB_MBAFF ? 1 : 17;
            uvoffset= MB_MBAFF ? 1 : 9;
            if(!MB_MBAFF){
                *(uint64_t*)(h->top_borders[0][s->mb_x]+ 0)= *(uint64_t*)(src_y +  15*linesize);
                *(uint64_t*)(h->top_borders[0][s->mb_x]+ 8)= *(uint64_t*)(src_y +8+15*linesize);
                if(simple || !CONFIG_GRAY || !(s->flags&CODEC_FLAG_GRAY)){
                    *(uint64_t*)(h->top_borders[0][s->mb_x]+16)= *(uint64_t*)(src_cb+7*uvlinesize);
                    *(uint64_t*)(h->top_borders[0][s->mb_x]+24)= *(uint64_t*)(src_cr+7*uvlinesize);
                }
            }
        }else{
            if(!MB_MBAFF){
                h->left_border[0]= h->top_borders[0][s->mb_x][15];
                if(simple || !CONFIG_GRAY || !(s->flags&CODEC_FLAG_GRAY)){
                    h->left_border[34   ]= h->top_borders[0][s->mb_x][16+7  ];
                    h->left_border[34+18]= h->top_borders[0][s->mb_x][16+8+7];
                }
                skiplast= 1;
            }
            offset  =
            uvoffset=
            top_idx = MB_MBAFF ? 0 : 1;
        }
        step= MB_MBAFF ? 2 : 1;
    }

    // There are two lines saved, the line above the the top macroblock of a pair,
    // and the line above the bottom macroblock
    h->left_border[offset]= h->top_borders[top_idx][s->mb_x][15];
    for(i=1; i<17 - skiplast; i++){
        h->left_border[offset+i*step]= src_y[15+i*  linesize];
    }

    *(uint64_t*)(h->top_borders[top_idx][s->mb_x]+0)= *(uint64_t*)(src_y +  16*linesize);
    *(uint64_t*)(h->top_borders[top_idx][s->mb_x]+8)= *(uint64_t*)(src_y +8+16*linesize);

    if(simple || !CONFIG_GRAY || !(s->flags&CODEC_FLAG_GRAY)){
        h->left_border[uvoffset+34   ]= h->top_borders[top_idx][s->mb_x][16+7];
        h->left_border[uvoffset+34+18]= h->top_borders[top_idx][s->mb_x][24+7];
        for(i=1; i<9 - skiplast; i++){
            h->left_border[uvoffset+34   +i*step]= src_cb[7+i*uvlinesize];
            h->left_border[uvoffset+34+18+i*step]= src_cr[7+i*uvlinesize];
        }
        *(uint64_t*)(h->top_borders[top_idx][s->mb_x]+16)= *(uint64_t*)(src_cb+8*uvlinesize);
        *(uint64_t*)(h->top_borders[top_idx][s->mb_x]+24)= *(uint64_t*)(src_cr+8*uvlinesize);
    }
}

static inline void xchg_mb_border(H264Context *h, uint8_t *src_y, uint8_t *src_cb, uint8_t *src_cr, int linesize, int uvlinesize, int xchg, int simple){
    MpegEncContext * const s = &h->s;
    int temp8, i;
    uint64_t temp64;
    int deblock_left;
    int deblock_top;
    int mb_xy;
    int step    = 1;
    int offset  = 1;
    int uvoffset= 1;
    int top_idx = 1;

    if(!simple && FRAME_MBAFF){
        if(s->mb_y&1){
            offset  = MB_MBAFF ? 1 : 17;
            uvoffset= MB_MBAFF ? 1 : 9;
        }else{
            offset  =
            uvoffset=
            top_idx = MB_MBAFF ? 0 : 1;
        }
        step= MB_MBAFF ? 2 : 1;
    }

    if(h->deblocking_filter == 2) {
        mb_xy = h->mb_xy;
        deblock_left = h->slice_table[mb_xy] == h->slice_table[mb_xy - 1];
        deblock_top  = h->slice_table[mb_xy] == h->slice_table[h->top_mb_xy];
    } else {
        deblock_left = (s->mb_x > 0);
        deblock_top =  (s->mb_y > !!MB_FIELD);
    }

    src_y  -=   linesize + 1;
    src_cb -= uvlinesize + 1;
    src_cr -= uvlinesize + 1;

#define XCHG(a,b,t,xchg)\
t= a;\
if(xchg)\
    a= b;\
b= t;

    if(deblock_left){
        for(i = !deblock_top; i<16; i++){
            XCHG(h->left_border[offset+i*step], src_y [i*  linesize], temp8, xchg);
        }
        XCHG(h->left_border[offset+i*step], src_y [i*  linesize], temp8, 1);
    }

    if(deblock_top){
        XCHG(*(uint64_t*)(h->top_borders[top_idx][s->mb_x]+0), *(uint64_t*)(src_y +1), temp64, xchg);
        XCHG(*(uint64_t*)(h->top_borders[top_idx][s->mb_x]+8), *(uint64_t*)(src_y +9), temp64, 1);
        if(s->mb_x+1 < s->mb_width){
            XCHG(*(uint64_t*)(h->top_borders[top_idx][s->mb_x+1]), *(uint64_t*)(src_y +17), temp64, 1);
        }
    }

    if(simple || !CONFIG_GRAY || !(s->flags&CODEC_FLAG_GRAY)){
        if(deblock_left){
            for(i = !deblock_top; i<8; i++){
                XCHG(h->left_border[uvoffset+34   +i*step], src_cb[i*uvlinesize], temp8, xchg);
                XCHG(h->left_border[uvoffset+34+18+i*step], src_cr[i*uvlinesize], temp8, xchg);
            }
            XCHG(h->left_border[uvoffset+34   +i*step], src_cb[i*uvlinesize], temp8, 1);
            XCHG(h->left_border[uvoffset+34+18+i*step], src_cr[i*uvlinesize], temp8, 1);
        }
        if(deblock_top){
            XCHG(*(uint64_t*)(h->top_borders[top_idx][s->mb_x]+16), *(uint64_t*)(src_cb+1), temp64, 1);
            XCHG(*(uint64_t*)(h->top_borders[top_idx][s->mb_x]+24), *(uint64_t*)(src_cr+1), temp64, 1);
        }
    }
}

static av_always_inline void hl_decode_mb_internal(H264Context *h, int simple){
    MpegEncContext * const s = &h->s;
    const int mb_x= s->mb_x;
    const int mb_y= s->mb_y;
    const int mb_xy= h->mb_xy;
    const int mb_type= s->current_picture.mb_type[mb_xy];
    uint8_t  *dest_y, *dest_cb, *dest_cr;
    int linesize, uvlinesize /*dct_offset*/;
    int i;
    int *block_offset = &h->block_offset[0];
    const int transform_bypass = !simple && (s->qscale == 0 && h->sps.transform_bypass);
    /* is_h264 should always be true if SVQ3 is disabled. */
    const int is_h264 = !CONFIG_SVQ3_DECODER || simple || s->codec_id == CODEC_ID_H264;
    void (*idct_add)(uint8_t *dst, DCTELEM *block, int stride);
    void (*idct_dc_add)(uint8_t *dst, DCTELEM *block, int stride);

    dest_y  = s->current_picture.data[0] + (mb_x + mb_y * s->linesize  ) * 16;
    dest_cb = s->current_picture.data[1] + (mb_x + mb_y * s->uvlinesize) * 8;
    dest_cr = s->current_picture.data[2] + (mb_x + mb_y * s->uvlinesize) * 8;

    s->dsp.prefetch(dest_y + (s->mb_x&3)*4*s->linesize + 64, s->linesize, 4);
    s->dsp.prefetch(dest_cb + (s->mb_x&7)*s->uvlinesize + 64, dest_cr - dest_cb, 2);

    if (!simple && MB_FIELD) {
        linesize   = h->mb_linesize   = s->linesize * 2;
        uvlinesize = h->mb_uvlinesize = s->uvlinesize * 2;
        block_offset = &h->block_offset[24];
        if(mb_y&1){ //FIXME move out of this function?
            dest_y -= s->linesize*15;
            dest_cb-= s->uvlinesize*7;
            dest_cr-= s->uvlinesize*7;
        }
        if(FRAME_MBAFF) {
            int list;
            for(list=0; list<h->list_count; list++){
                if(!USES_LIST(mb_type, list))
                    continue;
                if(IS_16X16(mb_type)){
                    int8_t *ref = &h->ref_cache[list][scan8[0]];
                    fill_rectangle(ref, 4, 4, 8, (16+*ref)^(s->mb_y&1), 1);
                }else{
                    for(i=0; i<16; i+=4){
                        int ref = h->ref_cache[list][scan8[i]];
                        if(ref >= 0)
                            fill_rectangle(&h->ref_cache[list][scan8[i]], 2, 2, 8, (16+ref)^(s->mb_y&1), 1);
                    }
                }
            }
        }
    } else {
        linesize   = h->mb_linesize   = s->linesize;
        uvlinesize = h->mb_uvlinesize = s->uvlinesize;
//        dct_offset = s->linesize * 16;
    }

    if (!simple && IS_INTRA_PCM(mb_type)) {
        for (i=0; i<16; i++) {
            memcpy(dest_y + i*  linesize, h->mb       + i*8, 16);
        }
        for (i=0; i<8; i++) {
            memcpy(dest_cb+ i*uvlinesize, h->mb + 128 + i*4,  8);
            memcpy(dest_cr+ i*uvlinesize, h->mb + 160 + i*4,  8);
        }
    } else {
        if(IS_INTRA(mb_type)){
            if(h->deblocking_filter)
                xchg_mb_border(h, dest_y, dest_cb, dest_cr, linesize, uvlinesize, 1, simple);

            if(simple || !CONFIG_GRAY || !(s->flags&CODEC_FLAG_GRAY)){
                h->hpc.pred8x8[ h->chroma_pred_mode ](dest_cb, uvlinesize);
                h->hpc.pred8x8[ h->chroma_pred_mode ](dest_cr, uvlinesize);
            }

            if(IS_INTRA4x4(mb_type)){
                if(simple || !s->encoding){
                    if(IS_8x8DCT(mb_type)){
                        if(transform_bypass){
                            idct_dc_add =
                            idct_add    = s->dsp.add_pixels8;
                        }else{
                            idct_dc_add = s->dsp.h264_idct8_dc_add;
                            idct_add    = s->dsp.h264_idct8_add;
                        }
                        for(i=0; i<16; i+=4){
                            uint8_t * const ptr= dest_y + block_offset[i];
                            const int dir= h->intra4x4_pred_mode_cache[ scan8[i] ];
                            if(transform_bypass && h->sps.profile_idc==244 && dir<=1){
                                h->hpc.pred8x8l_add[dir](ptr, h->mb + i*16, linesize);
                            }else{
                                const int nnz = h->non_zero_count_cache[ scan8[i] ];
                                h->hpc.pred8x8l[ dir ](ptr, (h->topleft_samples_available<<i)&0x8000,
                                                            (h->topright_samples_available<<i)&0x4000, linesize);
                                if(nnz){
                                    if(nnz == 1 && h->mb[i*16])
                                        idct_dc_add(ptr, h->mb + i*16, linesize);
                                    else
                                        idct_add   (ptr, h->mb + i*16, linesize);
                                }
                            }
                        }
                    }else{
                        if(transform_bypass){
                            idct_dc_add =
                            idct_add    = s->dsp.add_pixels4;
                        }else{
                            idct_dc_add = s->dsp.h264_idct_dc_add;
                            idct_add    = s->dsp.h264_idct_add;
                        }
                        for(i=0; i<16; i++){
                            uint8_t * const ptr= dest_y + block_offset[i];
                            const int dir= h->intra4x4_pred_mode_cache[ scan8[i] ];

                            if(transform_bypass && h->sps.profile_idc==244 && dir<=1){
                                h->hpc.pred4x4_add[dir](ptr, h->mb + i*16, linesize);
                            }else{
                                uint8_t *topright;
                                int nnz, tr;
                                if(dir == DIAG_DOWN_LEFT_PRED || dir == VERT_LEFT_PRED){
                                    const int topright_avail= (h->topright_samples_available<<i)&0x8000;
                                    assert(mb_y || linesize <= block_offset[i]);
                                    if(!topright_avail){
                                        tr= ptr[3 - linesize]*0x01010101;
                                        topright= (uint8_t*) &tr;
                                    }else
                                        topright= ptr + 4 - linesize;
                                }else
                                    topright= NULL;

                                h->hpc.pred4x4[ dir ](ptr, topright, linesize);
                                nnz = h->non_zero_count_cache[ scan8[i] ];
                                if(nnz){
                                    if(is_h264){
                                        if(nnz == 1 && h->mb[i*16])
                                            idct_dc_add(ptr, h->mb + i*16, linesize);
                                        else
                                            idct_add   (ptr, h->mb + i*16, linesize);
                                    }else
                                        svq3_add_idct_c(ptr, h->mb + i*16, linesize, s->qscale, 0);
                                }
                            }
                        }
                    }
                }
            }else{
                h->hpc.pred16x16[ h->intra16x16_pred_mode ](dest_y , linesize);
                if(is_h264){
                    if(!transform_bypass)
                        h264_luma_dc_dequant_idct_c(h->mb, s->qscale, h->dequant4_coeff[0][s->qscale][0]);
                }else
                    svq3_luma_dc_dequant_idct_c(h->mb, s->qscale);
            }
            if(h->deblocking_filter)
                xchg_mb_border(h, dest_y, dest_cb, dest_cr, linesize, uvlinesize, 0, simple);
        }else if(is_h264){
            hl_motion(h, dest_y, dest_cb, dest_cr,
                      s->me.qpel_put, s->dsp.put_h264_chroma_pixels_tab,
                      s->me.qpel_avg, s->dsp.avg_h264_chroma_pixels_tab,
                      s->dsp.weight_h264_pixels_tab, s->dsp.biweight_h264_pixels_tab);
        }


        if(!IS_INTRA4x4(mb_type)){
            if(is_h264){
                if(IS_INTRA16x16(mb_type)){
                    if(transform_bypass){
                        if(h->sps.profile_idc==244 && (h->intra16x16_pred_mode==VERT_PRED8x8 || h->intra16x16_pred_mode==HOR_PRED8x8)){
                            h->hpc.pred16x16_add[h->intra16x16_pred_mode](dest_y, block_offset, h->mb, linesize);
                        }else{
                            for(i=0; i<16; i++){
                                if(h->non_zero_count_cache[ scan8[i] ] || h->mb[i*16])
                                    s->dsp.add_pixels4(dest_y + block_offset[i], h->mb + i*16, linesize);
                            }
                        }
                    }else{
                         s->dsp.h264_idct_add16intra(dest_y, block_offset, h->mb, linesize, h->non_zero_count_cache);
                    }
                }else if(h->cbp&15){
                    if(transform_bypass){
                        const int di = IS_8x8DCT(mb_type) ? 4 : 1;
                        idct_add= IS_8x8DCT(mb_type) ? s->dsp.add_pixels8 : s->dsp.add_pixels4;
                        for(i=0; i<16; i+=di){
                            if(h->non_zero_count_cache[ scan8[i] ]){
                                idct_add(dest_y + block_offset[i], h->mb + i*16, linesize);
                            }
                        }
                    }else{
                        if(IS_8x8DCT(mb_type)){
                            s->dsp.h264_idct8_add4(dest_y, block_offset, h->mb, linesize, h->non_zero_count_cache);
                        }else{
                            s->dsp.h264_idct_add16(dest_y, block_offset, h->mb, linesize, h->non_zero_count_cache);
                        }
                    }
                }
            }else{
                for(i=0; i<16; i++){
                    if(h->non_zero_count_cache[ scan8[i] ] || h->mb[i*16]){ //FIXME benchmark weird rule, & below
                        uint8_t * const ptr= dest_y + block_offset[i];
                        svq3_add_idct_c(ptr, h->mb + i*16, linesize, s->qscale, IS_INTRA(mb_type) ? 1 : 0);
                    }
                }
            }
        }

        if((simple || !CONFIG_GRAY || !(s->flags&CODEC_FLAG_GRAY)) && (h->cbp&0x30)){
            uint8_t *dest[2] = {dest_cb, dest_cr};
            if(transform_bypass){
                if(IS_INTRA(mb_type) && h->sps.profile_idc==244 && (h->chroma_pred_mode==VERT_PRED8x8 || h->chroma_pred_mode==HOR_PRED8x8)){
                    h->hpc.pred8x8_add[h->chroma_pred_mode](dest[0], block_offset + 16, h->mb + 16*16, uvlinesize);
                    h->hpc.pred8x8_add[h->chroma_pred_mode](dest[1], block_offset + 20, h->mb + 20*16, uvlinesize);
                }else{
                    idct_add = s->dsp.add_pixels4;
                    for(i=16; i<16+8; i++){
                        if(h->non_zero_count_cache[ scan8[i] ] || h->mb[i*16])
                            idct_add   (dest[(i&4)>>2] + block_offset[i], h->mb + i*16, uvlinesize);
                    }
                }
            }else{
                chroma_dc_dequant_idct_c(h->mb + 16*16, h->chroma_qp[0], h->dequant4_coeff[IS_INTRA(mb_type) ? 1:4][h->chroma_qp[0]][0]);
                chroma_dc_dequant_idct_c(h->mb + 16*16+4*16, h->chroma_qp[1], h->dequant4_coeff[IS_INTRA(mb_type) ? 2:5][h->chroma_qp[1]][0]);
                if(is_h264){
                    idct_add = s->dsp.h264_idct_add;
                    idct_dc_add = s->dsp.h264_idct_dc_add;
                    for(i=16; i<16+8; i++){
                        if(h->non_zero_count_cache[ scan8[i] ])
                            idct_add   (dest[(i&4)>>2] + block_offset[i], h->mb + i*16, uvlinesize);
                        else if(h->mb[i*16])
                            idct_dc_add(dest[(i&4)>>2] + block_offset[i], h->mb + i*16, uvlinesize);
                    }
                }else{
                    for(i=16; i<16+8; i++){
                        if(h->non_zero_count_cache[ scan8[i] ] || h->mb[i*16]){
                            uint8_t * const ptr= dest[(i&4)>>2] + block_offset[i];
                            svq3_add_idct_c(ptr, h->mb + i*16, uvlinesize, ff_h264_chroma_qp[s->qscale + 12] - 12, 2);
                        }
                    }
                }
            }
        }
    }
    if(h->cbp || IS_INTRA(mb_type))
        s->dsp.clear_blocks(h->mb);

    if(h->deblocking_filter) {
        backup_mb_border(h, dest_y, dest_cb, dest_cr, linesize, uvlinesize, simple);
        fill_caches(h, mb_type, 1); //FIXME don't fill stuff which isn't used by filter_mb
        h->chroma_qp[0] = get_chroma_qp(h, 0, s->current_picture.qscale_table[mb_xy]);
        h->chroma_qp[1] = get_chroma_qp(h, 1, s->current_picture.qscale_table[mb_xy]);
        if (!simple && FRAME_MBAFF) {
            ff_h264_filter_mb     (h, mb_x, mb_y, dest_y, dest_cb, dest_cr, linesize, uvlinesize);
        } else {
            ff_h264_filter_mb_fast(h, mb_x, mb_y, dest_y, dest_cb, dest_cr, linesize, uvlinesize);
        }
    }
}

/**
 * Process a macroblock; this case avoids checks for expensive uncommon cases.
 */
static void hl_decode_mb_simple(H264Context *h){
    hl_decode_mb_internal(h, 1);
}

/**
 * Process a macroblock; this handles edge cases, such as interlacing.
 */
static void av_noinline hl_decode_mb_complex(H264Context *h){
    hl_decode_mb_internal(h, 0);
}

void ff_h264_hl_decode_mb(H264Context *h){
    MpegEncContext * const s = &h->s;
    const int mb_xy= h->mb_xy;
    const int mb_type= s->current_picture.mb_type[mb_xy];
    int is_complex = CONFIG_SMALL || h->is_complex || IS_INTRA_PCM(mb_type) || s->qscale == 0;

    if (is_complex)
        hl_decode_mb_complex(h);
    else hl_decode_mb_simple(h);
}

static int pred_weight_table(H264Context *h){
    MpegEncContext * const s = &h->s;
    int list, i;
    int luma_def, chroma_def;

    h->use_weight= 0;
    h->use_weight_chroma= 0;
    h->luma_log2_weight_denom= get_ue_golomb(&s->gb);
    h->chroma_log2_weight_denom= get_ue_golomb(&s->gb);
    luma_def = 1<<h->luma_log2_weight_denom;
    chroma_def = 1<<h->chroma_log2_weight_denom;

    for(list=0; list<2; list++){
        h->luma_weight_flag[list]   = 0;
        h->chroma_weight_flag[list] = 0;
        for(i=0; i<h->ref_count[list]; i++){
            int luma_weight_flag, chroma_weight_flag;

            luma_weight_flag= get_bits1(&s->gb);
            if(luma_weight_flag){
                h->luma_weight[list][i]= get_se_golomb(&s->gb);
                h->luma_offset[list][i]= get_se_golomb(&s->gb);
                if(   h->luma_weight[list][i] != luma_def
                   || h->luma_offset[list][i] != 0) {
                    h->use_weight= 1;
                    h->luma_weight_flag[list]= 1;
                }
            }else{
                h->luma_weight[list][i]= luma_def;
                h->luma_offset[list][i]= 0;
            }

            if(CHROMA){
                chroma_weight_flag= get_bits1(&s->gb);
                if(chroma_weight_flag){
                    int j;
                    for(j=0; j<2; j++){
                        h->chroma_weight[list][i][j]= get_se_golomb(&s->gb);
                        h->chroma_offset[list][i][j]= get_se_golomb(&s->gb);
                        if(   h->chroma_weight[list][i][j] != chroma_def
                           || h->chroma_offset[list][i][j] != 0) {
                            h->use_weight_chroma= 1;
                            h->chroma_weight_flag[list]= 1;
                        }
                    }
                }else{
                    int j;
                    for(j=0; j<2; j++){
                        h->chroma_weight[list][i][j]= chroma_def;
                        h->chroma_offset[list][i][j]= 0;
                    }
                }
            }
        }
        if(h->slice_type_nos != FF_B_TYPE) break;
    }
    h->use_weight= h->use_weight || h->use_weight_chroma;
    return 0;
}

static void implicit_weight_table(H264Context *h){
    MpegEncContext * const s = &h->s;
    int ref0, ref1, i;
    int cur_poc = s->current_picture_ptr->poc;

    for (i = 0; i < 2; i++) {
        h->luma_weight_flag[i]   = 0;
        h->chroma_weight_flag[i] = 0;
    }

    if(   h->ref_count[0] == 1 && h->ref_count[1] == 1
       && h->ref_list[0][0].poc + h->ref_list[1][0].poc == 2*cur_poc){
        h->use_weight= 0;
        h->use_weight_chroma= 0;
        return;
    }

    h->use_weight= 2;
    h->use_weight_chroma= 2;
    h->luma_log2_weight_denom= 5;
    h->chroma_log2_weight_denom= 5;

    for(ref0=0; ref0 < h->ref_count[0]; ref0++){
        int poc0 = h->ref_list[0][ref0].poc;
        for(ref1=0; ref1 < h->ref_count[1]; ref1++){
            int poc1 = h->ref_list[1][ref1].poc;
            int td = av_clip(poc1 - poc0, -128, 127);
            if(td){
                int tb = av_clip(cur_poc - poc0, -128, 127);
                int tx = (16384 + (FFABS(td) >> 1)) / td;
                int dist_scale_factor = av_clip((tb*tx + 32) >> 6, -1024, 1023) >> 2;
                if(dist_scale_factor < -64 || dist_scale_factor > 128)
                    h->implicit_weight[ref0][ref1] = 32;
                else
                    h->implicit_weight[ref0][ref1] = 64 - dist_scale_factor;
            }else
                h->implicit_weight[ref0][ref1] = 32;
        }
    }
}

/**
 * instantaneous decoder refresh.
 */
static void idr(H264Context *h){
    ff_h264_remove_all_refs(h);
    h->prev_frame_num= 0;
    h->prev_frame_num_offset= 0;
    h->prev_poc_msb=
    h->prev_poc_lsb= 0;
}

/* forget old pics after a seek */
static void flush_dpb(AVCodecContext *avctx){
    H264Context *h= avctx->priv_data;
    int i;
    for(i=0; i<MAX_DELAYED_PIC_COUNT; i++) {
        if(h->delayed_pic[i])
            h->delayed_pic[i]->reference= 0;
        h->delayed_pic[i]= NULL;
    }
    h->outputed_poc= INT_MIN;
    h->prev_interlaced_frame = 1;
    idr(h);
    if(h->s.current_picture_ptr)
        h->s.current_picture_ptr->reference= 0;
    h->s.first_field= 0;
    ff_h264_reset_sei(h);
    ff_mpeg_flush(avctx);
}

static int init_poc(H264Context *h){
    MpegEncContext * const s = &h->s;
    const int max_frame_num= 1<<h->sps.log2_max_frame_num;
    int field_poc[2];
    Picture *cur = s->current_picture_ptr;

    h->frame_num_offset= h->prev_frame_num_offset;
    if(h->frame_num < h->prev_frame_num)
        h->frame_num_offset += max_frame_num;

    if(h->sps.poc_type==0){
        const int max_poc_lsb= 1<<h->sps.log2_max_poc_lsb;

        if     (h->poc_lsb < h->prev_poc_lsb && h->prev_poc_lsb - h->poc_lsb >= max_poc_lsb/2)
            h->poc_msb = h->prev_poc_msb + max_poc_lsb;
        else if(h->poc_lsb > h->prev_poc_lsb && h->prev_poc_lsb - h->poc_lsb < -max_poc_lsb/2)
            h->poc_msb = h->prev_poc_msb - max_poc_lsb;
        else
            h->poc_msb = h->prev_poc_msb;
//printf("poc: %d %d\n", h->poc_msb, h->poc_lsb);
        field_poc[0] =
        field_poc[1] = h->poc_msb + h->poc_lsb;
        if(s->picture_structure == PICT_FRAME)
            field_poc[1] += h->delta_poc_bottom;
    }else if(h->sps.poc_type==1){
        int abs_frame_num, expected_delta_per_poc_cycle, expectedpoc;
        int i;

        if(h->sps.poc_cycle_length != 0)
            abs_frame_num = h->frame_num_offset + h->frame_num;
        else
            abs_frame_num = 0;

        if(h->nal_ref_idc==0 && abs_frame_num > 0)
            abs_frame_num--;

        expected_delta_per_poc_cycle = 0;
        for(i=0; i < h->sps.poc_cycle_length; i++)
            expected_delta_per_poc_cycle += h->sps.offset_for_ref_frame[ i ]; //FIXME integrate during sps parse

        if(abs_frame_num > 0){
            int poc_cycle_cnt          = (abs_frame_num - 1) / h->sps.poc_cycle_length;
            int frame_num_in_poc_cycle = (abs_frame_num - 1) % h->sps.poc_cycle_length;

            expectedpoc = poc_cycle_cnt * expected_delta_per_poc_cycle;
            for(i = 0; i <= frame_num_in_poc_cycle; i++)
                expectedpoc = expectedpoc + h->sps.offset_for_ref_frame[ i ];
        } else
            expectedpoc = 0;

        if(h->nal_ref_idc == 0)
            expectedpoc = expectedpoc + h->sps.offset_for_non_ref_pic;

        field_poc[0] = expectedpoc + h->delta_poc[0];
        field_poc[1] = field_poc[0] + h->sps.offset_for_top_to_bottom_field;

        if(s->picture_structure == PICT_FRAME)
            field_poc[1] += h->delta_poc[1];
    }else{
        int poc= 2*(h->frame_num_offset + h->frame_num);

        if(!h->nal_ref_idc)
            poc--;

        field_poc[0]= poc;
        field_poc[1]= poc;
    }

    if(s->picture_structure != PICT_BOTTOM_FIELD)
        s->current_picture_ptr->field_poc[0]= field_poc[0];
    if(s->picture_structure != PICT_TOP_FIELD)
        s->current_picture_ptr->field_poc[1]= field_poc[1];
    cur->poc= FFMIN(cur->field_poc[0], cur->field_poc[1]);

    return 0;
}


/**
 * initialize scan tables
 */
static void init_scan_tables(H264Context *h){
    MpegEncContext * const s = &h->s;
    int i;
    if(s->dsp.h264_idct_add == ff_h264_idct_add_c){ //FIXME little ugly
        memcpy(h->zigzag_scan, zigzag_scan, 16*sizeof(uint8_t));
        memcpy(h-> field_scan,  field_scan, 16*sizeof(uint8_t));
    }else{
        for(i=0; i<16; i++){
#define T(x) (x>>2) | ((x<<2) & 0xF)
            h->zigzag_scan[i] = T(zigzag_scan[i]);
            h-> field_scan[i] = T( field_scan[i]);
#undef T
        }
    }
    if(s->dsp.h264_idct8_add == ff_h264_idct8_add_c){
        memcpy(h->zigzag_scan8x8,       ff_zigzag_direct,     64*sizeof(uint8_t));
        memcpy(h->zigzag_scan8x8_cavlc, zigzag_scan8x8_cavlc, 64*sizeof(uint8_t));
        memcpy(h->field_scan8x8,        field_scan8x8,        64*sizeof(uint8_t));
        memcpy(h->field_scan8x8_cavlc,  field_scan8x8_cavlc,  64*sizeof(uint8_t));
    }else{
        for(i=0; i<64; i++){
#define T(x) (x>>3) | ((x&7)<<3)
            h->zigzag_scan8x8[i]       = T(ff_zigzag_direct[i]);
            h->zigzag_scan8x8_cavlc[i] = T(zigzag_scan8x8_cavlc[i]);
            h->field_scan8x8[i]        = T(field_scan8x8[i]);
            h->field_scan8x8_cavlc[i]  = T(field_scan8x8_cavlc[i]);
#undef T
        }
    }
    if(h->sps.transform_bypass){ //FIXME same ugly
        h->zigzag_scan_q0          = zigzag_scan;
        h->zigzag_scan8x8_q0       = ff_zigzag_direct;
        h->zigzag_scan8x8_cavlc_q0 = zigzag_scan8x8_cavlc;
        h->field_scan_q0           = field_scan;
        h->field_scan8x8_q0        = field_scan8x8;
        h->field_scan8x8_cavlc_q0  = field_scan8x8_cavlc;
    }else{
        h->zigzag_scan_q0          = h->zigzag_scan;
        h->zigzag_scan8x8_q0       = h->zigzag_scan8x8;
        h->zigzag_scan8x8_cavlc_q0 = h->zigzag_scan8x8_cavlc;
        h->field_scan_q0           = h->field_scan;
        h->field_scan8x8_q0        = h->field_scan8x8;
        h->field_scan8x8_cavlc_q0  = h->field_scan8x8_cavlc;
    }
}

static void field_end(H264Context *h){
    MpegEncContext * const s = &h->s;
    AVCodecContext * const avctx= s->avctx;
    s->mb_y= 0;

    s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_H264;
    s->current_picture_ptr->pict_type= s->pict_type;

    if (CONFIG_H264_VDPAU_DECODER && s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU)
        ff_vdpau_h264_set_reference_frames(s);

    if(!s->dropable) {
        ff_h264_execute_ref_pic_marking(h, h->mmco, h->mmco_index);
        h->prev_poc_msb= h->poc_msb;
        h->prev_poc_lsb= h->poc_lsb;
    }
    h->prev_frame_num_offset= h->frame_num_offset;
    h->prev_frame_num= h->frame_num;

    if (avctx->hwaccel) {
        if (avctx->hwaccel->end_frame(avctx) < 0)
            av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode picture\n");
    }

    if (CONFIG_H264_VDPAU_DECODER && s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU)
        ff_vdpau_h264_picture_complete(s);

    /*
     * FIXME: Error handling code does not seem to support interlaced
     * when slices span multiple rows
     * The ff_er_add_slice calls don't work right for bottom
     * fields; they cause massive erroneous error concealing
     * Error marking covers both fields (top and bottom).
     * This causes a mismatched s->error_count
     * and a bad error table. Further, the error count goes to
     * INT_MAX when called for bottom field, because mb_y is
     * past end by one (callers fault) and resync_mb_y != 0
     * causes problems for the first MB line, too.
     */
    if (!FIELD_PICTURE)
        ff_er_frame_end(s);

    MPV_frame_end(s);

    h->current_slice=0;
}

/**
 * Replicates H264 "master" context to thread contexts.
 */
static void clone_slice(H264Context *dst, H264Context *src)
{
    memcpy(dst->block_offset,     src->block_offset, sizeof(dst->block_offset));
    dst->s.current_picture_ptr  = src->s.current_picture_ptr;
    dst->s.current_picture      = src->s.current_picture;
    dst->s.linesize             = src->s.linesize;
    dst->s.uvlinesize           = src->s.uvlinesize;
    dst->s.first_field          = src->s.first_field;

    dst->prev_poc_msb           = src->prev_poc_msb;
    dst->prev_poc_lsb           = src->prev_poc_lsb;
    dst->prev_frame_num_offset  = src->prev_frame_num_offset;
    dst->prev_frame_num         = src->prev_frame_num;
    dst->short_ref_count        = src->short_ref_count;

    memcpy(dst->short_ref,        src->short_ref,        sizeof(dst->short_ref));
    memcpy(dst->long_ref,         src->long_ref,         sizeof(dst->long_ref));
    memcpy(dst->default_ref_list, src->default_ref_list, sizeof(dst->default_ref_list));
    memcpy(dst->ref_list,         src->ref_list,         sizeof(dst->ref_list));

    memcpy(dst->dequant4_coeff,   src->dequant4_coeff,   sizeof(src->dequant4_coeff));
    memcpy(dst->dequant8_coeff,   src->dequant8_coeff,   sizeof(src->dequant8_coeff));
}

/**
 * decodes a slice header.
 * This will also call MPV_common_init() and frame_start() as needed.
 *
 * @param h h264context
 * @param h0 h264 master context (differs from 'h' when doing sliced based parallel decoding)
 *
 * @return 0 if okay, <0 if an error occurred, 1 if decoding must not be multithreaded
 */
static int decode_slice_header(H264Context *h, H264Context *h0){
    MpegEncContext * const s = &h->s;
    MpegEncContext * const s0 = &h0->s;
    unsigned int first_mb_in_slice;
    unsigned int pps_id;
    int num_ref_idx_active_override_flag;
    unsigned int slice_type, tmp, i, j;
    int default_ref_list_done = 0;
    int last_pic_structure;

    s->dropable= h->nal_ref_idc == 0;

    if((s->avctx->flags2 & CODEC_FLAG2_FAST) && !h->nal_ref_idc){
        s->me.qpel_put= s->dsp.put_2tap_qpel_pixels_tab;
        s->me.qpel_avg= s->dsp.avg_2tap_qpel_pixels_tab;
    }else{
        s->me.qpel_put= s->dsp.put_h264_qpel_pixels_tab;
        s->me.qpel_avg= s->dsp.avg_h264_qpel_pixels_tab;
    }

    first_mb_in_slice= get_ue_golomb(&s->gb);

    if(first_mb_in_slice == 0){ //FIXME better field boundary detection
        if(h0->current_slice && FIELD_PICTURE){
            field_end(h);
        }

        h0->current_slice = 0;
        if (!s0->first_field)
            s->current_picture_ptr= NULL;
    }

    slice_type= get_ue_golomb_31(&s->gb);
    if(slice_type > 9){
        av_log(h->s.avctx, AV_LOG_ERROR, "slice type too large (%d) at %d %d\n", h->slice_type, s->mb_x, s->mb_y);
        return -1;
    }
    if(slice_type > 4){
        slice_type -= 5;
        h->slice_type_fixed=1;
    }else
        h->slice_type_fixed=0;

    slice_type= golomb_to_pict_type[ slice_type ];
    if (slice_type == FF_I_TYPE
        || (h0->current_slice != 0 && slice_type == h0->last_slice_type) ) {
        default_ref_list_done = 1;
    }
    h->slice_type= slice_type;
    h->slice_type_nos= slice_type & 3;

    s->pict_type= h->slice_type; // to make a few old functions happy, it's wrong though
    if (s->pict_type == FF_B_TYPE && s0->last_picture_ptr == NULL) {
        av_log(h->s.avctx, AV_LOG_ERROR,
               "B picture before any references, skipping\n");
        return -1;
    }

    pps_id= get_ue_golomb(&s->gb);
    if(pps_id>=MAX_PPS_COUNT){
        av_log(h->s.avctx, AV_LOG_ERROR, "pps_id out of range\n");
        return -1;
    }
    if(!h0->pps_buffers[pps_id]) {
        av_log(h->s.avctx, AV_LOG_ERROR, "non-existing PPS %u referenced\n", pps_id);
        return -1;
    }
    h->pps= *h0->pps_buffers[pps_id];

    if(!h0->sps_buffers[h->pps.sps_id]) {
        av_log(h->s.avctx, AV_LOG_ERROR, "non-existing SPS %u referenced\n", h->pps.sps_id);
        return -1;
    }
    h->sps = *h0->sps_buffers[h->pps.sps_id];

    if(h == h0 && h->dequant_coeff_pps != pps_id){
        h->dequant_coeff_pps = pps_id;
        init_dequant_tables(h);
    }

    s->mb_width= h->sps.mb_width;
    s->mb_height= h->sps.mb_height * (2 - h->sps.frame_mbs_only_flag);

    h->b_stride=  s->mb_width*4;
    h->b8_stride= s->mb_width*2;

    s->width = 16*s->mb_width - 2*FFMIN(h->sps.crop_right, 7);
    if(h->sps.frame_mbs_only_flag)
        s->height= 16*s->mb_height - 2*FFMIN(h->sps.crop_bottom, 7);
    else
        s->height= 16*s->mb_height - 4*FFMIN(h->sps.crop_bottom, 3);

    if (s->context_initialized
        && (   s->width != s->avctx->width || s->height != s->avctx->height)) {
        if(h != h0)
            return -1;   // width / height changed during parallelized decoding
        free_tables(h);
        flush_dpb(s->avctx);
        MPV_common_end(s);
    }
    if (!s->context_initialized) {
        if(h != h0)
            return -1;  // we cant (re-)initialize context during parallel decoding

        avcodec_set_dimensions(s->avctx, s->width, s->height);
        s->avctx->sample_aspect_ratio= h->sps.sar;
        if(!s->avctx->sample_aspect_ratio.den)
            s->avctx->sample_aspect_ratio.den = 1;

        if(h->sps.video_signal_type_present_flag){
            s->avctx->color_range = h->sps.full_range ? AVCOL_RANGE_JPEG : AVCOL_RANGE_MPEG;
            if(h->sps.colour_description_present_flag){
                s->avctx->color_primaries = h->sps.color_primaries;
                s->avctx->color_trc       = h->sps.color_trc;
                s->avctx->colorspace      = h->sps.colorspace;
            }
        }

        if(h->sps.timing_info_present_flag){
            s->avctx->time_base= (AVRational){h->sps.num_units_in_tick, h->sps.time_scale};
            if(h->x264_build > 0 && h->x264_build < 44)
                s->avctx->time_base.den *= 2;
            av_reduce(&s->avctx->time_base.num, &s->avctx->time_base.den,
                      s->avctx->time_base.num, s->avctx->time_base.den, 1<<30);
        }
        s->avctx->pix_fmt = s->avctx->get_format(s->avctx, s->avctx->codec->pix_fmts);
        s->avctx->hwaccel = ff_find_hwaccel(s->avctx->codec->id, s->avctx->pix_fmt);

        if (MPV_common_init(s) < 0)
            return -1;
        s->first_field = 0;
        h->prev_interlaced_frame = 1;

        init_scan_tables(h);
        ff_h264_alloc_tables(h);

        for(i = 1; i < s->avctx->thread_count; i++) {
            H264Context *c;
            c = h->thread_context[i] = av_malloc(sizeof(H264Context));
            memcpy(c, h->s.thread_context[i], sizeof(MpegEncContext));
            memset(&c->s + 1, 0, sizeof(H264Context) - sizeof(MpegEncContext));
            c->sps = h->sps;
            c->pps = h->pps;
            init_scan_tables(c);
            clone_tables(c, h);
        }

        for(i = 0; i < s->avctx->thread_count; i++)
            if(context_init(h->thread_context[i]) < 0)
                return -1;
    }

    h->frame_num= get_bits(&s->gb, h->sps.log2_max_frame_num);

    h->mb_mbaff = 0;
    h->mb_aff_frame = 0;
    last_pic_structure = s0->picture_structure;
    if(h->sps.frame_mbs_only_flag){
        s->picture_structure= PICT_FRAME;
    }else{
        if(get_bits1(&s->gb)) { //field_pic_flag
            s->picture_structure= PICT_TOP_FIELD + get_bits1(&s->gb); //bottom_field_flag
        } else {
            s->picture_structure= PICT_FRAME;
            h->mb_aff_frame = h->sps.mb_aff;
        }
    }
    h->mb_field_decoding_flag= s->picture_structure != PICT_FRAME;

    if(h0->current_slice == 0){
        while(h->frame_num !=  h->prev_frame_num &&
              h->frame_num != (h->prev_frame_num+1)%(1<<h->sps.log2_max_frame_num)){
            av_log(NULL, AV_LOG_DEBUG, "Frame num gap %d %d\n", h->frame_num, h->prev_frame_num);
            if (ff_h264_frame_start(h) < 0)
                return -1;
            h->prev_frame_num++;
            h->prev_frame_num %= 1<<h->sps.log2_max_frame_num;
            s->current_picture_ptr->frame_num= h->prev_frame_num;
            ff_h264_execute_ref_pic_marking(h, NULL, 0);
        }

        /* See if we have a decoded first field looking for a pair... */
        if (s0->first_field) {
            assert(s0->current_picture_ptr);
            assert(s0->current_picture_ptr->data[0]);
            assert(s0->current_picture_ptr->reference != DELAYED_PIC_REF);

            /* figure out if we have a complementary field pair */
            if (!FIELD_PICTURE || s->picture_structure == last_pic_structure) {
                /*
                 * Previous field is unmatched. Don't display it, but let it
                 * remain for reference if marked as such.
                 */
                s0->current_picture_ptr = NULL;
                s0->first_field = FIELD_PICTURE;

            } else {
                if (h->nal_ref_idc &&
                        s0->current_picture_ptr->reference &&
                        s0->current_picture_ptr->frame_num != h->frame_num) {
                    /*
                     * This and previous field were reference, but had
                     * different frame_nums. Consider this field first in
                     * pair. Throw away previous field except for reference
                     * purposes.
                     */
                    s0->first_field = 1;
                    s0->current_picture_ptr = NULL;

                } else {
                    /* Second field in complementary pair */
                    s0->first_field = 0;
                }
            }

        } else {
            /* Frame or first field in a potentially complementary pair */
            assert(!s0->current_picture_ptr);
            s0->first_field = FIELD_PICTURE;
        }

        if((!FIELD_PICTURE || s0->first_field) && ff_h264_frame_start(h) < 0) {
            s0->first_field = 0;
            return -1;
        }
    }
    if(h != h0)
        clone_slice(h, h0);

    s->current_picture_ptr->frame_num= h->frame_num; //FIXME frame_num cleanup

    assert(s->mb_num == s->mb_width * s->mb_height);
    if(first_mb_in_slice << FIELD_OR_MBAFF_PICTURE >= s->mb_num ||
       first_mb_in_slice                    >= s->mb_num){
        av_log(h->s.avctx, AV_LOG_ERROR, "first_mb_in_slice overflow\n");
        return -1;
    }
    s->resync_mb_x = s->mb_x = first_mb_in_slice % s->mb_width;
    s->resync_mb_y = s->mb_y = (first_mb_in_slice / s->mb_width) << FIELD_OR_MBAFF_PICTURE;
    if (s->picture_structure == PICT_BOTTOM_FIELD)
        s->resync_mb_y = s->mb_y = s->mb_y + 1;
    assert(s->mb_y < s->mb_height);

    if(s->picture_structure==PICT_FRAME){
        h->curr_pic_num=   h->frame_num;
        h->max_pic_num= 1<< h->sps.log2_max_frame_num;
    }else{
        h->curr_pic_num= 2*h->frame_num + 1;
        h->max_pic_num= 1<<(h->sps.log2_max_frame_num + 1);
    }

    if(h->nal_unit_type == NAL_IDR_SLICE){
        get_ue_golomb(&s->gb); /* idr_pic_id */
    }

    if(h->sps.poc_type==0){
        h->poc_lsb= get_bits(&s->gb, h->sps.log2_max_poc_lsb);

        if(h->pps.pic_order_present==1 && s->picture_structure==PICT_FRAME){
            h->delta_poc_bottom= get_se_golomb(&s->gb);
        }
    }

    if(h->sps.poc_type==1 && !h->sps.delta_pic_order_always_zero_flag){
        h->delta_poc[0]= get_se_golomb(&s->gb);

        if(h->pps.pic_order_present==1 && s->picture_structure==PICT_FRAME)
            h->delta_poc[1]= get_se_golomb(&s->gb);
    }

    init_poc(h);

    if(h->pps.redundant_pic_cnt_present){
        h->redundant_pic_count= get_ue_golomb(&s->gb);
    }

    //set defaults, might be overridden a few lines later
    h->ref_count[0]= h->pps.ref_count[0];
    h->ref_count[1]= h->pps.ref_count[1];

    if(h->slice_type_nos != FF_I_TYPE){
        if(h->slice_type_nos == FF_B_TYPE){
            h->direct_spatial_mv_pred= get_bits1(&s->gb);
        }
        num_ref_idx_active_override_flag= get_bits1(&s->gb);

        if(num_ref_idx_active_override_flag){
            h->ref_count[0]= get_ue_golomb(&s->gb) + 1;
            if(h->slice_type_nos==FF_B_TYPE)
                h->ref_count[1]= get_ue_golomb(&s->gb) + 1;

            if(h->ref_count[0]-1 > 32-1 || h->ref_count[1]-1 > 32-1){
                av_log(h->s.avctx, AV_LOG_ERROR, "reference overflow\n");
                h->ref_count[0]= h->ref_count[1]= 1;
                return -1;
            }
        }
        if(h->slice_type_nos == FF_B_TYPE)
            h->list_count= 2;
        else
            h->list_count= 1;
    }else
        h->list_count= 0;

    if(!default_ref_list_done){
        ff_h264_fill_default_ref_list(h);
    }

    if(h->slice_type_nos!=FF_I_TYPE && ff_h264_decode_ref_pic_list_reordering(h) < 0)
        return -1;

    if(h->slice_type_nos!=FF_I_TYPE){
        s->last_picture_ptr= &h->ref_list[0][0];
        ff_copy_picture(&s->last_picture, s->last_picture_ptr);
    }
    if(h->slice_type_nos==FF_B_TYPE){
        s->next_picture_ptr= &h->ref_list[1][0];
        ff_copy_picture(&s->next_picture, s->next_picture_ptr);
    }

    if(   (h->pps.weighted_pred          && h->slice_type_nos == FF_P_TYPE )
       ||  (h->pps.weighted_bipred_idc==1 && h->slice_type_nos== FF_B_TYPE ) )
        pred_weight_table(h);
    else if(h->pps.weighted_bipred_idc==2 && h->slice_type_nos== FF_B_TYPE)
        implicit_weight_table(h);
    else {
        h->use_weight = 0;
        for (i = 0; i < 2; i++) {
            h->luma_weight_flag[i]   = 0;
            h->chroma_weight_flag[i] = 0;
        }
    }

    if(h->nal_ref_idc)
        ff_h264_decode_ref_pic_marking(h0, &s->gb);

    if(FRAME_MBAFF)
        ff_h264_fill_mbaff_ref_list(h);

    if(h->slice_type_nos==FF_B_TYPE && !h->direct_spatial_mv_pred)
        ff_h264_direct_dist_scale_factor(h);
    ff_h264_direct_ref_list_init(h);

    if( h->slice_type_nos != FF_I_TYPE && h->pps.cabac ){
        tmp = get_ue_golomb_31(&s->gb);
        if(tmp > 2){
            av_log(s->avctx, AV_LOG_ERROR, "cabac_init_idc overflow\n");
            return -1;
        }
        h->cabac_init_idc= tmp;
    }

    h->last_qscale_diff = 0;
    tmp = h->pps.init_qp + get_se_golomb(&s->gb);
    if(tmp>51){
        av_log(s->avctx, AV_LOG_ERROR, "QP %u out of range\n", tmp);
        return -1;
    }
    s->qscale= tmp;
    h->chroma_qp[0] = get_chroma_qp(h, 0, s->qscale);
    h->chroma_qp[1] = get_chroma_qp(h, 1, s->qscale);
    //FIXME qscale / qp ... stuff
    if(h->slice_type == FF_SP_TYPE){
        get_bits1(&s->gb); /* sp_for_switch_flag */
    }
    if(h->slice_type==FF_SP_TYPE || h->slice_type == FF_SI_TYPE){
        get_se_golomb(&s->gb); /* slice_qs_delta */
    }

    h->deblocking_filter = 1;
    h->slice_alpha_c0_offset = 0;
    h->slice_beta_offset = 0;
    if( h->pps.deblocking_filter_parameters_present ) {
        tmp= get_ue_golomb_31(&s->gb);
        if(tmp > 2){
            av_log(s->avctx, AV_LOG_ERROR, "deblocking_filter_idc %u out of range\n", tmp);
            return -1;
        }
        h->deblocking_filter= tmp;
        if(h->deblocking_filter < 2)
            h->deblocking_filter^= 1; // 1<->0

        if( h->deblocking_filter ) {
            h->slice_alpha_c0_offset = get_se_golomb(&s->gb) << 1;
            h->slice_beta_offset = get_se_golomb(&s->gb) << 1;
        }
    }

    if(   s->avctx->skip_loop_filter >= AVDISCARD_ALL
       ||(s->avctx->skip_loop_filter >= AVDISCARD_NONKEY && h->slice_type_nos != FF_I_TYPE)
       ||(s->avctx->skip_loop_filter >= AVDISCARD_BIDIR  && h->slice_type_nos == FF_B_TYPE)
       ||(s->avctx->skip_loop_filter >= AVDISCARD_NONREF && h->nal_ref_idc == 0))
        h->deblocking_filter= 0;

    if(h->deblocking_filter == 1 && h0->max_contexts > 1) {
        if(s->avctx->flags2 & CODEC_FLAG2_FAST) {
            /* Cheat slightly for speed:
               Do not bother to deblock across slices. */
            h->deblocking_filter = 2;
        } else {
            h0->max_contexts = 1;
            if(!h0->single_decode_warning) {
                av_log(s->avctx, AV_LOG_INFO, "Cannot parallelize deblocking type 1, decoding such frames in sequential order\n");
                h0->single_decode_warning = 1;
            }
            if(h != h0)
                return 1; // deblocking switched inside frame
        }
    }

#if 0 //FMO
    if( h->pps.num_slice_groups > 1  && h->pps.mb_slice_group_map_type >= 3 && h->pps.mb_slice_group_map_type <= 5)
        slice_group_change_cycle= get_bits(&s->gb, ?);
#endif

    h0->last_slice_type = slice_type;
    h->slice_num = ++h0->current_slice;
    if(h->slice_num >= MAX_SLICES){
        av_log(s->avctx, AV_LOG_ERROR, "Too many slices, increase MAX_SLICES and recompile\n");
    }

    for(j=0; j<2; j++){
        int *ref2frm= h->ref2frm[h->slice_num&(MAX_SLICES-1)][j];
        ref2frm[0]=
        ref2frm[1]= -1;
        for(i=0; i<16; i++)
            ref2frm[i+2]= 4*h->ref_list[j][i].frame_num
                          +(h->ref_list[j][i].reference&3);
        ref2frm[18+0]=
        ref2frm[18+1]= -1;
        for(i=16; i<48; i++)
            ref2frm[i+4]= 4*h->ref_list[j][i].frame_num
                          +(h->ref_list[j][i].reference&3);
    }

    h->emu_edge_width= (s->flags&CODEC_FLAG_EMU_EDGE) ? 0 : 16;
    h->emu_edge_height= (FRAME_MBAFF || FIELD_PICTURE) ? 0 : h->emu_edge_width;

    s->avctx->refs= h->sps.ref_frame_count;

    if(s->avctx->debug&FF_DEBUG_PICT_INFO){
        av_log(h->s.avctx, AV_LOG_DEBUG, "slice:%d %s mb:%d %c%s%s pps:%u frame:%d poc:%d/%d ref:%d/%d qp:%d loop:%d:%d:%d weight:%d%s %s\n",
               h->slice_num,
               (s->picture_structure==PICT_FRAME ? "F" : s->picture_structure==PICT_TOP_FIELD ? "T" : "B"),
               first_mb_in_slice,
               av_get_pict_type_char(h->slice_type), h->slice_type_fixed ? " fix" : "", h->nal_unit_type == NAL_IDR_SLICE ? " IDR" : "",
               pps_id, h->frame_num,
               s->current_picture_ptr->field_poc[0], s->current_picture_ptr->field_poc[1],
               h->ref_count[0], h->ref_count[1],
               s->qscale,
               h->deblocking_filter, h->slice_alpha_c0_offset/2, h->slice_beta_offset/2,
               h->use_weight,
               h->use_weight==1 && h->use_weight_chroma ? "c" : "",
               h->slice_type == FF_B_TYPE ? (h->direct_spatial_mv_pred ? "SPAT" : "TEMP") : ""
               );
    }

    return 0;
}

int ff_h264_get_slice_type(H264Context *h)
{
    switch (h->slice_type) {
    case FF_P_TYPE:  return 0;
    case FF_B_TYPE:  return 1;
    case FF_I_TYPE:  return 2;
    case FF_SP_TYPE: return 3;
    case FF_SI_TYPE: return 4;
    default:         return -1;
    }
}


static int decode_cabac_field_decoding_flag(H264Context *h) {
    MpegEncContext * const s = &h->s;
    const int mb_x = s->mb_x;
    const int mb_y = s->mb_y & ~1;
    const int mba_xy = mb_x - 1 +  mb_y   *s->mb_stride;
    const int mbb_xy = mb_x     + (mb_y-2)*s->mb_stride;

    unsigned int ctx = 0;

    if( h->slice_table[mba_xy] == h->slice_num && IS_INTERLACED( s->current_picture.mb_type[mba_xy] ) ) {
        ctx += 1;
    }
    if( h->slice_table[mbb_xy] == h->slice_num && IS_INTERLACED( s->current_picture.mb_type[mbb_xy] ) ) {
        ctx += 1;
    }

    return get_cabac_noinline( &h->cabac, &h->cabac_state[70 + ctx] );
}

static int decode_cabac_intra_mb_type(H264Context *h, int ctx_base, int intra_slice) {
    uint8_t *state= &h->cabac_state[ctx_base];
    int mb_type;

    if(intra_slice){
        MpegEncContext * const s = &h->s;
        const int mba_xy = h->left_mb_xy[0];
        const int mbb_xy = h->top_mb_xy;
        int ctx=0;
        if( h->slice_table[mba_xy] == h->slice_num && !IS_INTRA4x4( s->current_picture.mb_type[mba_xy] ) )
            ctx++;
        if( h->slice_table[mbb_xy] == h->slice_num && !IS_INTRA4x4( s->current_picture.mb_type[mbb_xy] ) )
            ctx++;
        if( get_cabac_noinline( &h->cabac, &state[ctx] ) == 0 )
            return 0;   /* I4x4 */
        state += 2;
    }else{
        if( get_cabac_noinline( &h->cabac, &state[0] ) == 0 )
            return 0;   /* I4x4 */
    }

    if( get_cabac_terminate( &h->cabac ) )
        return 25;  /* PCM */

    mb_type = 1; /* I16x16 */
    mb_type += 12 * get_cabac_noinline( &h->cabac, &state[1] ); /* cbp_luma != 0 */
    if( get_cabac_noinline( &h->cabac, &state[2] ) ) /* cbp_chroma */
        mb_type += 4 + 4 * get_cabac_noinline( &h->cabac, &state[2+intra_slice] );
    mb_type += 2 * get_cabac_noinline( &h->cabac, &state[3+intra_slice] );
    mb_type += 1 * get_cabac_noinline( &h->cabac, &state[3+2*intra_slice] );
    return mb_type;
}

static int decode_cabac_mb_type_b( H264Context *h ) {
    MpegEncContext * const s = &h->s;

        const int mba_xy = h->left_mb_xy[0];
        const int mbb_xy = h->top_mb_xy;
        int ctx = 0;
        int bits;
        assert(h->slice_type_nos == FF_B_TYPE);

        if( h->slice_table[mba_xy] == h->slice_num && !IS_DIRECT( s->current_picture.mb_type[mba_xy] ) )
            ctx++;
        if( h->slice_table[mbb_xy] == h->slice_num && !IS_DIRECT( s->current_picture.mb_type[mbb_xy] ) )
            ctx++;

        if( !get_cabac_noinline( &h->cabac, &h->cabac_state[27+ctx] ) )
            return 0; /* B_Direct_16x16 */

        if( !get_cabac_noinline( &h->cabac, &h->cabac_state[27+3] ) ) {
            return 1 + get_cabac_noinline( &h->cabac, &h->cabac_state[27+5] ); /* B_L[01]_16x16 */
        }

        bits = get_cabac_noinline( &h->cabac, &h->cabac_state[27+4] ) << 3;
        bits|= get_cabac_noinline( &h->cabac, &h->cabac_state[27+5] ) << 2;
        bits|= get_cabac_noinline( &h->cabac, &h->cabac_state[27+5] ) << 1;
        bits|= get_cabac_noinline( &h->cabac, &h->cabac_state[27+5] );
        if( bits < 8 )
            return bits + 3; /* B_Bi_16x16 through B_L1_L0_16x8 */
        else if( bits == 13 ) {
            return decode_cabac_intra_mb_type(h, 32, 0) + 23;
        } else if( bits == 14 )
            return 11; /* B_L1_L0_8x16 */
        else if( bits == 15 )
            return 22; /* B_8x8 */

        bits= ( bits<<1 ) | get_cabac_noinline( &h->cabac, &h->cabac_state[27+5] );
        return bits - 4; /* B_L0_Bi_* through B_Bi_Bi_* */
}

static int decode_cabac_mb_skip( H264Context *h, int mb_x, int mb_y ) {
    MpegEncContext * const s = &h->s;
    int mba_xy, mbb_xy;
    int ctx = 0;

    if(FRAME_MBAFF){ //FIXME merge with the stuff in fill_caches?
        int mb_xy = mb_x + (mb_y&~1)*s->mb_stride;
        mba_xy = mb_xy - 1;
        if( (mb_y&1)
            && h->slice_table[mba_xy] == h->slice_num
            && MB_FIELD == !!IS_INTERLACED( s->current_picture.mb_type[mba_xy] ) )
            mba_xy += s->mb_stride;
        if( MB_FIELD ){
            mbb_xy = mb_xy - s->mb_stride;
            if( !(mb_y&1)
                && h->slice_table[mbb_xy] == h->slice_num
                && IS_INTERLACED( s->current_picture.mb_type[mbb_xy] ) )
                mbb_xy -= s->mb_stride;
        }else
            mbb_xy = mb_x + (mb_y-1)*s->mb_stride;
    }else{
        int mb_xy = h->mb_xy;
        mba_xy = mb_xy - 1;
        mbb_xy = mb_xy - (s->mb_stride << FIELD_PICTURE);
    }

    if( h->slice_table[mba_xy] == h->slice_num && !IS_SKIP( s->current_picture.mb_type[mba_xy] ))
        ctx++;
    if( h->slice_table[mbb_xy] == h->slice_num && !IS_SKIP( s->current_picture.mb_type[mbb_xy] ))
        ctx++;

    if( h->slice_type_nos == FF_B_TYPE )
        ctx += 13;
    return get_cabac_noinline( &h->cabac, &h->cabac_state[11+ctx] );
}

static int decode_cabac_mb_intra4x4_pred_mode( H264Context *h, int pred_mode ) {
    int mode = 0;

    if( get_cabac( &h->cabac, &h->cabac_state[68] ) )
        return pred_mode;

    mode += 1 * get_cabac( &h->cabac, &h->cabac_state[69] );
    mode += 2 * get_cabac( &h->cabac, &h->cabac_state[69] );
    mode += 4 * get_cabac( &h->cabac, &h->cabac_state[69] );

    if( mode >= pred_mode )
        return mode + 1;
    else
        return mode;
}

static int decode_cabac_mb_chroma_pre_mode( H264Context *h) {
    const int mba_xy = h->left_mb_xy[0];
    const int mbb_xy = h->top_mb_xy;

    int ctx = 0;

    /* No need to test for IS_INTRA4x4 and IS_INTRA16x16, as we set chroma_pred_mode_table to 0 */
    if( h->slice_table[mba_xy] == h->slice_num && h->chroma_pred_mode_table[mba_xy] != 0 )
        ctx++;

    if( h->slice_table[mbb_xy] == h->slice_num && h->chroma_pred_mode_table[mbb_xy] != 0 )
        ctx++;

    if( get_cabac_noinline( &h->cabac, &h->cabac_state[64+ctx] ) == 0 )
        return 0;

    if( get_cabac_noinline( &h->cabac, &h->cabac_state[64+3] ) == 0 )
        return 1;
    if( get_cabac_noinline( &h->cabac, &h->cabac_state[64+3] ) == 0 )
        return 2;
    else
        return 3;
}

static int decode_cabac_mb_cbp_luma( H264Context *h) {
    int cbp_b, cbp_a, ctx, cbp = 0;

    cbp_a = h->slice_table[h->left_mb_xy[0]] == h->slice_num ? h->left_cbp : -1;
    cbp_b = h->slice_table[h->top_mb_xy]     == h->slice_num ? h->top_cbp  : -1;

    ctx = !(cbp_a & 0x02) + 2 * !(cbp_b & 0x04);
    cbp |= get_cabac_noinline(&h->cabac, &h->cabac_state[73 + ctx]);
    ctx = !(cbp   & 0x01) + 2 * !(cbp_b & 0x08);
    cbp |= get_cabac_noinline(&h->cabac, &h->cabac_state[73 + ctx]) << 1;
    ctx = !(cbp_a & 0x08) + 2 * !(cbp   & 0x01);
    cbp |= get_cabac_noinline(&h->cabac, &h->cabac_state[73 + ctx]) << 2;
    ctx = !(cbp   & 0x04) + 2 * !(cbp   & 0x02);
    cbp |= get_cabac_noinline(&h->cabac, &h->cabac_state[73 + ctx]) << 3;
    return cbp;
}
static int decode_cabac_mb_cbp_chroma( H264Context *h) {
    int ctx;
    int cbp_a, cbp_b;

    cbp_a = (h->left_cbp>>4)&0x03;
    cbp_b = (h-> top_cbp>>4)&0x03;

    ctx = 0;
    if( cbp_a > 0 ) ctx++;
    if( cbp_b > 0 ) ctx += 2;
    if( get_cabac_noinline( &h->cabac, &h->cabac_state[77 + ctx] ) == 0 )
        return 0;

    ctx = 4;
    if( cbp_a == 2 ) ctx++;
    if( cbp_b == 2 ) ctx += 2;
    return 1 + get_cabac_noinline( &h->cabac, &h->cabac_state[77 + ctx] );
}
static int decode_cabac_mb_dqp( H264Context *h) {
    int   ctx= h->last_qscale_diff != 0;
    int   val = 0;

    while( get_cabac_noinline( &h->cabac, &h->cabac_state[60 + ctx] ) ) {
        ctx= 2+(ctx>>1);
        val++;
        if(val > 102) //prevent infinite loop
            return INT_MIN;
    }

    if( val&0x01 )
        return   (val + 1)>>1 ;
    else
        return -((val + 1)>>1);
}
static int decode_cabac_p_mb_sub_type( H264Context *h ) {
    if( get_cabac( &h->cabac, &h->cabac_state[21] ) )
        return 0;   /* 8x8 */
    if( !get_cabac( &h->cabac, &h->cabac_state[22] ) )
        return 1;   /* 8x4 */
    if( get_cabac( &h->cabac, &h->cabac_state[23] ) )
        return 2;   /* 4x8 */
    return 3;       /* 4x4 */
}
static int decode_cabac_b_mb_sub_type( H264Context *h ) {
    int type;
    if( !get_cabac( &h->cabac, &h->cabac_state[36] ) )
        return 0;   /* B_Direct_8x8 */
    if( !get_cabac( &h->cabac, &h->cabac_state[37] ) )
        return 1 + get_cabac( &h->cabac, &h->cabac_state[39] ); /* B_L0_8x8, B_L1_8x8 */
    type = 3;
    if( get_cabac( &h->cabac, &h->cabac_state[38] ) ) {
        if( get_cabac( &h->cabac, &h->cabac_state[39] ) )
            return 11 + get_cabac( &h->cabac, &h->cabac_state[39] ); /* B_L1_4x4, B_Bi_4x4 */
        type += 4;
    }
    type += 2*get_cabac( &h->cabac, &h->cabac_state[39] );
    type +=   get_cabac( &h->cabac, &h->cabac_state[39] );
    return type;
}

static inline int decode_cabac_mb_transform_size( H264Context *h ) {
    return get_cabac_noinline( &h->cabac, &h->cabac_state[399 + h->neighbor_transform_size] );
}

static int decode_cabac_mb_ref( H264Context *h, int list, int n ) {
    int refa = h->ref_cache[list][scan8[n] - 1];
    int refb = h->ref_cache[list][scan8[n] - 8];
    int ref  = 0;
    int ctx  = 0;

    if( h->slice_type_nos == FF_B_TYPE) {
        if( refa > 0 && !h->direct_cache[scan8[n] - 1] )
            ctx++;
        if( refb > 0 && !h->direct_cache[scan8[n] - 8] )
            ctx += 2;
    } else {
        if( refa > 0 )
            ctx++;
        if( refb > 0 )
            ctx += 2;
    }

    while( get_cabac( &h->cabac, &h->cabac_state[54+ctx] ) ) {
        ref++;
        ctx = (ctx>>2)+4;
        if(ref >= 32 /*h->ref_list[list]*/){
            return -1;
        }
    }
    return ref;
}

static int decode_cabac_mb_mvd( H264Context *h, int list, int n, int l ) {
    int amvd = abs( h->mvd_cache[list][scan8[n] - 1][l] ) +
               abs( h->mvd_cache[list][scan8[n] - 8][l] );
    int ctxbase = (l == 0) ? 40 : 47;
    int mvd;
    int ctx = (amvd>2) + (amvd>32);

    if(!get_cabac(&h->cabac, &h->cabac_state[ctxbase+ctx]))
        return 0;

    mvd= 1;
    ctx= 3;
    while( mvd < 9 && get_cabac( &h->cabac, &h->cabac_state[ctxbase+ctx] ) ) {
        mvd++;
        if( ctx < 6 )
            ctx++;
    }

    if( mvd >= 9 ) {
        int k = 3;
        while( get_cabac_bypass( &h->cabac ) ) {
            mvd += 1 << k;
            k++;
            if(k>24){
                av_log(h->s.avctx, AV_LOG_ERROR, "overflow in decode_cabac_mb_mvd\n");
                return INT_MIN;
            }
        }
        while( k-- ) {
            if( get_cabac_bypass( &h->cabac ) )
                mvd += 1 << k;
        }
    }
    return get_cabac_bypass_sign( &h->cabac, -mvd );
}

static av_always_inline int get_cabac_cbf_ctx( H264Context *h, int cat, int idx, int is_dc ) {
    int nza, nzb;
    int ctx = 0;

    if( is_dc ) {
        if( cat == 0 ) {
            nza = h->left_cbp&0x100;
            nzb = h-> top_cbp&0x100;
        } else {
            nza = (h->left_cbp>>(6+idx))&0x01;
            nzb = (h-> top_cbp>>(6+idx))&0x01;
        }
    } else {
        assert(cat == 1 || cat == 2 || cat == 4);
        nza = h->non_zero_count_cache[scan8[idx] - 1];
        nzb = h->non_zero_count_cache[scan8[idx] - 8];
    }

    if( nza > 0 )
        ctx++;

    if( nzb > 0 )
        ctx += 2;

    return ctx + 4 * cat;
}

DECLARE_ASM_CONST(1, uint8_t, last_coeff_flag_offset_8x8[63]) = {
    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
    3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4,
    5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8
};

static av_always_inline void decode_cabac_residual_internal( H264Context *h, DCTELEM *block, int cat, int n, const uint8_t *scantable, const uint32_t *qmul, int max_coeff, int is_dc ) {
    static const int significant_coeff_flag_offset[2][6] = {
      { 105+0, 105+15, 105+29, 105+44, 105+47, 402 },
      { 277+0, 277+15, 277+29, 277+44, 277+47, 436 }
    };
    static const int last_coeff_flag_offset[2][6] = {
      { 166+0, 166+15, 166+29, 166+44, 166+47, 417 },
      { 338+0, 338+15, 338+29, 338+44, 338+47, 451 }
    };
    static const int coeff_abs_level_m1_offset[6] = {
        227+0, 227+10, 227+20, 227+30, 227+39, 426
    };
    static const uint8_t significant_coeff_flag_offset_8x8[2][63] = {
      { 0, 1, 2, 3, 4, 5, 5, 4, 4, 3, 3, 4, 4, 4, 5, 5,
        4, 4, 4, 4, 3, 3, 6, 7, 7, 7, 8, 9,10, 9, 8, 7,
        7, 6,11,12,13,11, 6, 7, 8, 9,14,10, 9, 8, 6,11,
       12,13,11, 6, 9,14,10, 9,11,12,13,11,14,10,12 },
      { 0, 1, 1, 2, 2, 3, 3, 4, 5, 6, 7, 7, 7, 8, 4, 5,
        6, 9,10,10, 8,11,12,11, 9, 9,10,10, 8,11,12,11,
        9, 9,10,10, 8,11,12,11, 9, 9,10,10, 8,13,13, 9,
        9,10,10, 8,13,13, 9, 9,10,10,14,14,14,14,14 }
    };
    /* node ctx: 0..3: abslevel1 (with abslevelgt1 == 0).
     * 4..7: abslevelgt1 + 3 (and abslevel1 doesn't matter).
     * map node ctx => cabac ctx for level=1 */
    static const uint8_t coeff_abs_level1_ctx[8] = { 1, 2, 3, 4, 0, 0, 0, 0 };
    /* map node ctx => cabac ctx for level>1 */
    static const uint8_t coeff_abs_levelgt1_ctx[8] = { 5, 5, 5, 5, 6, 7, 8, 9 };
    static const uint8_t coeff_abs_level_transition[2][8] = {
    /* update node ctx after decoding a level=1 */
        { 1, 2, 3, 3, 4, 5, 6, 7 },
    /* update node ctx after decoding a level>1 */
        { 4, 4, 4, 4, 5, 6, 7, 7 }
    };

    int index[64];

    int av_unused last;
    int coeff_count = 0;
    int node_ctx = 0;

    uint8_t *significant_coeff_ctx_base;
    uint8_t *last_coeff_ctx_base;
    uint8_t *abs_level_m1_ctx_base;

#if !ARCH_X86
#define CABAC_ON_STACK
#endif
#ifdef CABAC_ON_STACK
#define CC &cc
    CABACContext cc;
    cc.range     = h->cabac.range;
    cc.low       = h->cabac.low;
    cc.bytestream= h->cabac.bytestream;
#else
#define CC &h->cabac
#endif


    /* cat: 0-> DC 16x16  n = 0
     *      1-> AC 16x16  n = luma4x4idx
     *      2-> Luma4x4   n = luma4x4idx
     *      3-> DC Chroma n = iCbCr
     *      4-> AC Chroma n = 16 + 4 * iCbCr + chroma4x4idx
     *      5-> Luma8x8   n = 4 * luma8x8idx
     */

    /* read coded block flag */
    if( is_dc || cat != 5 ) {
        if( get_cabac( CC, &h->cabac_state[85 + get_cabac_cbf_ctx( h, cat, n, is_dc ) ] ) == 0 ) {
            if( !is_dc )
                h->non_zero_count_cache[scan8[n]] = 0;

#ifdef CABAC_ON_STACK
            h->cabac.range     = cc.range     ;
            h->cabac.low       = cc.low       ;
            h->cabac.bytestream= cc.bytestream;
#endif
            return;
        }
    }

    significant_coeff_ctx_base = h->cabac_state
        + significant_coeff_flag_offset[MB_FIELD][cat];
    last_coeff_ctx_base = h->cabac_state
        + last_coeff_flag_offset[MB_FIELD][cat];
    abs_level_m1_ctx_base = h->cabac_state
        + coeff_abs_level_m1_offset[cat];

    if( !is_dc && cat == 5 ) {
#define DECODE_SIGNIFICANCE( coefs, sig_off, last_off ) \
        for(last= 0; last < coefs; last++) { \
            uint8_t *sig_ctx = significant_coeff_ctx_base + sig_off; \
            if( get_cabac( CC, sig_ctx )) { \
                uint8_t *last_ctx = last_coeff_ctx_base + last_off; \
                index[coeff_count++] = last; \
                if( get_cabac( CC, last_ctx ) ) { \
                    last= max_coeff; \
                    break; \
                } \
            } \
        }\
        if( last == max_coeff -1 ) {\
            index[coeff_count++] = last;\
        }
        const uint8_t *sig_off = significant_coeff_flag_offset_8x8[MB_FIELD];
#if ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE && !defined(BROKEN_RELOCATIONS)
        coeff_count= decode_significance_8x8_x86(CC, significant_coeff_ctx_base, index, sig_off);
    } else {
        coeff_count= decode_significance_x86(CC, max_coeff, significant_coeff_ctx_base, index);
#else
        DECODE_SIGNIFICANCE( 63, sig_off[last], last_coeff_flag_offset_8x8[last] );
    } else {
        DECODE_SIGNIFICANCE( max_coeff - 1, last, last );
#endif
    }
    assert(coeff_count > 0);

    if( is_dc ) {
        if( cat == 0 )
            h->cbp_table[h->mb_xy] |= 0x100;
        else
            h->cbp_table[h->mb_xy] |= 0x40 << n;
    } else {
        if( cat == 5 )
            fill_rectangle(&h->non_zero_count_cache[scan8[n]], 2, 2, 8, coeff_count, 1);
        else {
            assert( cat == 1 || cat == 2 || cat == 4 );
            h->non_zero_count_cache[scan8[n]] = coeff_count;
        }
    }

    do {
        uint8_t *ctx = coeff_abs_level1_ctx[node_ctx] + abs_level_m1_ctx_base;

        int j= scantable[index[--coeff_count]];

        if( get_cabac( CC, ctx ) == 0 ) {
            node_ctx = coeff_abs_level_transition[0][node_ctx];
            if( is_dc ) {
                block[j] = get_cabac_bypass_sign( CC, -1);
            }else{
                block[j] = (get_cabac_bypass_sign( CC, -qmul[j]) + 32) >> 6;
            }
        } else {
            int coeff_abs = 2;
            ctx = coeff_abs_levelgt1_ctx[node_ctx] + abs_level_m1_ctx_base;
            node_ctx = coeff_abs_level_transition[1][node_ctx];

            while( coeff_abs < 15 && get_cabac( CC, ctx ) ) {
                coeff_abs++;
            }

            if( coeff_abs >= 15 ) {
                int j = 0;
                while( get_cabac_bypass( CC ) ) {
                    j++;
                }

                coeff_abs=1;
                while( j-- ) {
                    coeff_abs += coeff_abs + get_cabac_bypass( CC );
                }
                coeff_abs+= 14;
            }

            if( is_dc ) {
                block[j] = get_cabac_bypass_sign( CC, -coeff_abs );
            }else{
                block[j] = (get_cabac_bypass_sign( CC, -coeff_abs ) * qmul[j] + 32) >> 6;
            }
        }
    } while( coeff_count );
#ifdef CABAC_ON_STACK
            h->cabac.range     = cc.range     ;
            h->cabac.low       = cc.low       ;
            h->cabac.bytestream= cc.bytestream;
#endif

}

#if !CONFIG_SMALL
static void decode_cabac_residual_dc( H264Context *h, DCTELEM *block, int cat, int n, const uint8_t *scantable, const uint32_t *qmul, int max_coeff ) {
    decode_cabac_residual_internal(h, block, cat, n, scantable, qmul, max_coeff, 1);
}

static void decode_cabac_residual_nondc( H264Context *h, DCTELEM *block, int cat, int n, const uint8_t *scantable, const uint32_t *qmul, int max_coeff ) {
    decode_cabac_residual_internal(h, block, cat, n, scantable, qmul, max_coeff, 0);
}
#endif

static void decode_cabac_residual( H264Context *h, DCTELEM *block, int cat, int n, const uint8_t *scantable, const uint32_t *qmul, int max_coeff ) {
#if CONFIG_SMALL
    decode_cabac_residual_internal(h, block, cat, n, scantable, qmul, max_coeff, cat == 0 || cat == 3);
#else
    if( cat == 0 || cat == 3 ) decode_cabac_residual_dc(h, block, cat, n, scantable, qmul, max_coeff);
    else decode_cabac_residual_nondc(h, block, cat, n, scantable, qmul, max_coeff);
#endif
}

static inline void compute_mb_neighbors(H264Context *h)
{
    MpegEncContext * const s = &h->s;
    const int mb_xy  = h->mb_xy;
    h->top_mb_xy     = mb_xy - s->mb_stride;
    h->left_mb_xy[0] = mb_xy - 1;
    if(FRAME_MBAFF){
        const int pair_xy          = s->mb_x     + (s->mb_y & ~1)*s->mb_stride;
        const int top_pair_xy      = pair_xy     - s->mb_stride;
        const int top_mb_field_flag  = IS_INTERLACED(s->current_picture.mb_type[top_pair_xy]);
        const int left_mb_field_flag = IS_INTERLACED(s->current_picture.mb_type[pair_xy-1]);
        const int curr_mb_field_flag = MB_FIELD;
        const int bottom = (s->mb_y & 1);

        if (curr_mb_field_flag && (bottom || top_mb_field_flag)){
            h->top_mb_xy -= s->mb_stride;
        }
        if (!left_mb_field_flag == curr_mb_field_flag) {
            h->left_mb_xy[0] = pair_xy - 1;
        }
    } else if (FIELD_PICTURE) {
        h->top_mb_xy -= s->mb_stride;
    }
    return;
}

/**
 * decodes a macroblock
 * @returns 0 if OK, AC_ERROR / DC_ERROR / MV_ERROR if an error is noticed
 */
static int decode_mb_cabac(H264Context *h) {
    MpegEncContext * const s = &h->s;
    int mb_xy;
    int mb_type, partition_count, cbp = 0;
    int dct8x8_allowed= h->pps.transform_8x8_mode;

    mb_xy = h->mb_xy = s->mb_x + s->mb_y*s->mb_stride;

    tprintf(s->avctx, "pic:%d mb:%d/%d\n", h->frame_num, s->mb_x, s->mb_y);
    if( h->slice_type_nos != FF_I_TYPE ) {
        int skip;
        /* a skipped mb needs the aff flag from the following mb */
        if( FRAME_MBAFF && s->mb_x==0 && (s->mb_y&1)==0 )
            predict_field_decoding_flag(h);
        if( FRAME_MBAFF && (s->mb_y&1)==1 && h->prev_mb_skipped )
            skip = h->next_mb_skipped;
        else
            skip = decode_cabac_mb_skip( h, s->mb_x, s->mb_y );
        /* read skip flags */
        if( skip ) {
            if( FRAME_MBAFF && (s->mb_y&1)==0 ){
                s->current_picture.mb_type[mb_xy] = MB_TYPE_SKIP;
                h->next_mb_skipped = decode_cabac_mb_skip( h, s->mb_x, s->mb_y+1 );
                if(!h->next_mb_skipped)
                    h->mb_mbaff = h->mb_field_decoding_flag = decode_cabac_field_decoding_flag(h);
            }

            decode_mb_skip(h);

            h->cbp_table[mb_xy] = 0;
            h->chroma_pred_mode_table[mb_xy] = 0;
            h->last_qscale_diff = 0;

            return 0;

        }
    }
    if(FRAME_MBAFF){
        if( (s->mb_y&1) == 0 )
            h->mb_mbaff =
            h->mb_field_decoding_flag = decode_cabac_field_decoding_flag(h);
    }

    h->prev_mb_skipped = 0;

    compute_mb_neighbors(h);

    if( h->slice_type_nos == FF_B_TYPE ) {
        mb_type = decode_cabac_mb_type_b( h );
        if( mb_type < 23 ){
            partition_count= b_mb_type_info[mb_type].partition_count;
            mb_type=         b_mb_type_info[mb_type].type;
        }else{
            mb_type -= 23;
            goto decode_intra_mb;
        }
    } else if( h->slice_type_nos == FF_P_TYPE ) {
        if( get_cabac_noinline( &h->cabac, &h->cabac_state[14] ) == 0 ) {
            /* P-type */
            if( get_cabac_noinline( &h->cabac, &h->cabac_state[15] ) == 0 ) {
                /* P_L0_D16x16, P_8x8 */
                mb_type= 3 * get_cabac_noinline( &h->cabac, &h->cabac_state[16] );
            } else {
                /* P_L0_D8x16, P_L0_D16x8 */
                mb_type= 2 - get_cabac_noinline( &h->cabac, &h->cabac_state[17] );
            }
            partition_count= p_mb_type_info[mb_type].partition_count;
            mb_type=         p_mb_type_info[mb_type].type;
        } else {
            mb_type= decode_cabac_intra_mb_type(h, 17, 0);
            goto decode_intra_mb;
        }
    } else {
        mb_type= decode_cabac_intra_mb_type(h, 3, 1);
        if(h->slice_type == FF_SI_TYPE && mb_type)
            mb_type--;
        assert(h->slice_type_nos == FF_I_TYPE);
decode_intra_mb:
        partition_count = 0;
        cbp= i_mb_type_info[mb_type].cbp;
        h->intra16x16_pred_mode= i_mb_type_info[mb_type].pred_mode;
        mb_type= i_mb_type_info[mb_type].type;
    }
    if(MB_FIELD)
        mb_type |= MB_TYPE_INTERLACED;

    h->slice_table[ mb_xy ]= h->slice_num;

    if(IS_INTRA_PCM(mb_type)) {
        const uint8_t *ptr;

        // We assume these blocks are very rare so we do not optimize it.
        // FIXME The two following lines get the bitstream position in the cabac
        // decode, I think it should be done by a function in cabac.h (or cabac.c).
        ptr= h->cabac.bytestream;
        if(h->cabac.low&0x1) ptr--;
        if(CABAC_BITS==16){
            if(h->cabac.low&0x1FF) ptr--;
        }

        // The pixels are stored in the same order as levels in h->mb array.
        memcpy(h->mb, ptr, 256); ptr+=256;
        if(CHROMA){
            memcpy(h->mb+128, ptr, 128); ptr+=128;
        }

        ff_init_cabac_decoder(&h->cabac, ptr, h->cabac.bytestream_end - ptr);

        // All blocks are present
        h->cbp_table[mb_xy] = 0x1ef;
        h->chroma_pred_mode_table[mb_xy] = 0;
        // In deblocking, the quantizer is 0
        s->current_picture.qscale_table[mb_xy]= 0;
        // All coeffs are present
        memset(h->non_zero_count[mb_xy], 16, 16);
        s->current_picture.mb_type[mb_xy]= mb_type;
        h->last_qscale_diff = 0;
        return 0;
    }

    if(MB_MBAFF){
        h->ref_count[0] <<= 1;
        h->ref_count[1] <<= 1;
    }

    fill_caches(h, mb_type, 0);

    if( IS_INTRA( mb_type ) ) {
        int i, pred_mode;
        if( IS_INTRA4x4( mb_type ) ) {
            if( dct8x8_allowed && decode_cabac_mb_transform_size( h ) ) {
                mb_type |= MB_TYPE_8x8DCT;
                for( i = 0; i < 16; i+=4 ) {
                    int pred = pred_intra_mode( h, i );
                    int mode = decode_cabac_mb_intra4x4_pred_mode( h, pred );
                    fill_rectangle( &h->intra4x4_pred_mode_cache[ scan8[i] ], 2, 2, 8, mode, 1 );
                }
            } else {
                for( i = 0; i < 16; i++ ) {
                    int pred = pred_intra_mode( h, i );
                    h->intra4x4_pred_mode_cache[ scan8[i] ] = decode_cabac_mb_intra4x4_pred_mode( h, pred );

                //av_log( s->avctx, AV_LOG_ERROR, "i4x4 pred=%d mode=%d\n", pred, h->intra4x4_pred_mode_cache[ scan8[i] ] );
                }
            }
            ff_h264_write_back_intra_pred_mode(h);
            if( ff_h264_check_intra4x4_pred_mode(h) < 0 ) return -1;
        } else {
            h->intra16x16_pred_mode= ff_h264_check_intra_pred_mode( h, h->intra16x16_pred_mode );
            if( h->intra16x16_pred_mode < 0 ) return -1;
        }
        if(CHROMA){
            h->chroma_pred_mode_table[mb_xy] =
            pred_mode                        = decode_cabac_mb_chroma_pre_mode( h );

            pred_mode= ff_h264_check_intra_pred_mode( h, pred_mode );
            if( pred_mode < 0 ) return -1;
            h->chroma_pred_mode= pred_mode;
        }
    } else if( partition_count == 4 ) {
        int i, j, sub_partition_count[4], list, ref[2][4];

        if( h->slice_type_nos == FF_B_TYPE ) {
            for( i = 0; i < 4; i++ ) {
                h->sub_mb_type[i] = decode_cabac_b_mb_sub_type( h );
                sub_partition_count[i]= b_sub_mb_type_info[ h->sub_mb_type[i] ].partition_count;
                h->sub_mb_type[i]=      b_sub_mb_type_info[ h->sub_mb_type[i] ].type;
            }
            if( IS_DIRECT(h->sub_mb_type[0] | h->sub_mb_type[1] |
                          h->sub_mb_type[2] | h->sub_mb_type[3]) ) {
                ff_h264_pred_direct_motion(h, &mb_type);
                h->ref_cache[0][scan8[4]] =
                h->ref_cache[1][scan8[4]] =
                h->ref_cache[0][scan8[12]] =
                h->ref_cache[1][scan8[12]] = PART_NOT_AVAILABLE;
                if( h->ref_count[0] > 1 || h->ref_count[1] > 1 ) {
                    for( i = 0; i < 4; i++ )
                        if( IS_DIRECT(h->sub_mb_type[i]) )
                            fill_rectangle( &h->direct_cache[scan8[4*i]], 2, 2, 8, 1, 1 );
                }
            }
        } else {
            for( i = 0; i < 4; i++ ) {
                h->sub_mb_type[i] = decode_cabac_p_mb_sub_type( h );
                sub_partition_count[i]= p_sub_mb_type_info[ h->sub_mb_type[i] ].partition_count;
                h->sub_mb_type[i]=      p_sub_mb_type_info[ h->sub_mb_type[i] ].type;
            }
        }

        for( list = 0; list < h->list_count; list++ ) {
                for( i = 0; i < 4; i++ ) {
                    if(IS_DIRECT(h->sub_mb_type[i])) continue;
                    if(IS_DIR(h->sub_mb_type[i], 0, list)){
                        if( h->ref_count[list] > 1 ){
                            ref[list][i] = decode_cabac_mb_ref( h, list, 4*i );
                            if(ref[list][i] >= (unsigned)h->ref_count[list]){
                                av_log(s->avctx, AV_LOG_ERROR, "Reference %d >= %d\n", ref[list][i], h->ref_count[list]);
                                return -1;
                            }
                        }else
                            ref[list][i] = 0;
                    } else {
                        ref[list][i] = -1;
                    }
                                                       h->ref_cache[list][ scan8[4*i]+1 ]=
                    h->ref_cache[list][ scan8[4*i]+8 ]=h->ref_cache[list][ scan8[4*i]+9 ]= ref[list][i];
                }
        }

        if(dct8x8_allowed)
            dct8x8_allowed = get_dct8x8_allowed(h);

        for(list=0; list<h->list_count; list++){
            for(i=0; i<4; i++){
                h->ref_cache[list][ scan8[4*i]   ]=h->ref_cache[list][ scan8[4*i]+1 ];
                if(IS_DIRECT(h->sub_mb_type[i])){
                    fill_rectangle(h->mvd_cache[list][scan8[4*i]], 2, 2, 8, 0, 4);
                    continue;
                }

                if(IS_DIR(h->sub_mb_type[i], 0, list) && !IS_DIRECT(h->sub_mb_type[i])){
                    const int sub_mb_type= h->sub_mb_type[i];
                    const int block_width= (sub_mb_type & (MB_TYPE_16x16|MB_TYPE_16x8)) ? 2 : 1;
                    for(j=0; j<sub_partition_count[i]; j++){
                        int mpx, mpy;
                        int mx, my;
                        const int index= 4*i + block_width*j;
                        int16_t (* mv_cache)[2]= &h->mv_cache[list][ scan8[index] ];
                        int16_t (* mvd_cache)[2]= &h->mvd_cache[list][ scan8[index] ];
                        pred_motion(h, index, block_width, list, h->ref_cache[list][ scan8[index] ], &mpx, &mpy);

                        mx = mpx + decode_cabac_mb_mvd( h, list, index, 0 );
                        my = mpy + decode_cabac_mb_mvd( h, list, index, 1 );
                        tprintf(s->avctx, "final mv:%d %d\n", mx, my);

                        if(IS_SUB_8X8(sub_mb_type)){
                            mv_cache[ 1 ][0]=
                            mv_cache[ 8 ][0]= mv_cache[ 9 ][0]= mx;
                            mv_cache[ 1 ][1]=
                            mv_cache[ 8 ][1]= mv_cache[ 9 ][1]= my;

                            mvd_cache[ 1 ][0]=
                            mvd_cache[ 8 ][0]= mvd_cache[ 9 ][0]= mx - mpx;
                            mvd_cache[ 1 ][1]=
                            mvd_cache[ 8 ][1]= mvd_cache[ 9 ][1]= my - mpy;
                        }else if(IS_SUB_8X4(sub_mb_type)){
                            mv_cache[ 1 ][0]= mx;
                            mv_cache[ 1 ][1]= my;

                            mvd_cache[ 1 ][0]= mx - mpx;
                            mvd_cache[ 1 ][1]= my - mpy;
                        }else if(IS_SUB_4X8(sub_mb_type)){
                            mv_cache[ 8 ][0]= mx;
                            mv_cache[ 8 ][1]= my;

                            mvd_cache[ 8 ][0]= mx - mpx;
                            mvd_cache[ 8 ][1]= my - mpy;
                        }
                        mv_cache[ 0 ][0]= mx;
                        mv_cache[ 0 ][1]= my;

                        mvd_cache[ 0 ][0]= mx - mpx;
                        mvd_cache[ 0 ][1]= my - mpy;
                    }
                }else{
                    uint32_t *p= (uint32_t *)&h->mv_cache[list][ scan8[4*i] ][0];
                    uint32_t *pd= (uint32_t *)&h->mvd_cache[list][ scan8[4*i] ][0];
                    p[0] = p[1] = p[8] = p[9] = 0;
                    pd[0]= pd[1]= pd[8]= pd[9]= 0;
                }
            }
        }
    } else if( IS_DIRECT(mb_type) ) {
        ff_h264_pred_direct_motion(h, &mb_type);
        fill_rectangle(h->mvd_cache[0][scan8[0]], 4, 4, 8, 0, 4);
        fill_rectangle(h->mvd_cache[1][scan8[0]], 4, 4, 8, 0, 4);
        dct8x8_allowed &= h->sps.direct_8x8_inference_flag;
    } else {
        int list, mx, my, i, mpx, mpy;
        if(IS_16X16(mb_type)){
            for(list=0; list<h->list_count; list++){
                if(IS_DIR(mb_type, 0, list)){
                    int ref;
                    if(h->ref_count[list] > 1){
                        ref= decode_cabac_mb_ref(h, list, 0);
                        if(ref >= (unsigned)h->ref_count[list]){
                            av_log(s->avctx, AV_LOG_ERROR, "Reference %d >= %d\n", ref, h->ref_count[list]);
                            return -1;
                        }
                    }else
                        ref=0;
                        fill_rectangle(&h->ref_cache[list][ scan8[0] ], 4, 4, 8, ref, 1);
                }else
                    fill_rectangle(&h->ref_cache[list][ scan8[0] ], 4, 4, 8, (uint8_t)LIST_NOT_USED, 1); //FIXME factorize and the other fill_rect below too
            }
            for(list=0; list<h->list_count; list++){
                if(IS_DIR(mb_type, 0, list)){
                    pred_motion(h, 0, 4, list, h->ref_cache[list][ scan8[0] ], &mpx, &mpy);

                    mx = mpx + decode_cabac_mb_mvd( h, list, 0, 0 );
                    my = mpy + decode_cabac_mb_mvd( h, list, 0, 1 );
                    tprintf(s->avctx, "final mv:%d %d\n", mx, my);

                    fill_rectangle(h->mvd_cache[list][ scan8[0] ], 4, 4, 8, pack16to32(mx-mpx,my-mpy), 4);
                    fill_rectangle(h->mv_cache[list][ scan8[0] ], 4, 4, 8, pack16to32(mx,my), 4);
                }else
                    fill_rectangle(h->mv_cache[list][ scan8[0] ], 4, 4, 8, 0, 4);
            }
        }
        else if(IS_16X8(mb_type)){
            for(list=0; list<h->list_count; list++){
                    for(i=0; i<2; i++){
                        if(IS_DIR(mb_type, i, list)){
                            int ref;
                            if(h->ref_count[list] > 1){
                                ref= decode_cabac_mb_ref( h, list, 8*i );
                                if(ref >= (unsigned)h->ref_count[list]){
                                    av_log(s->avctx, AV_LOG_ERROR, "Reference %d >= %d\n", ref, h->ref_count[list]);
                                    return -1;
                                }
                            }else
                                ref=0;
                            fill_rectangle(&h->ref_cache[list][ scan8[0] + 16*i ], 4, 2, 8, ref, 1);
                        }else
                            fill_rectangle(&h->ref_cache[list][ scan8[0] + 16*i ], 4, 2, 8, (LIST_NOT_USED&0xFF), 1);
                    }
            }
            for(list=0; list<h->list_count; list++){
                for(i=0; i<2; i++){
                    if(IS_DIR(mb_type, i, list)){
                        pred_16x8_motion(h, 8*i, list, h->ref_cache[list][scan8[0] + 16*i], &mpx, &mpy);
                        mx = mpx + decode_cabac_mb_mvd( h, list, 8*i, 0 );
                        my = mpy + decode_cabac_mb_mvd( h, list, 8*i, 1 );
                        tprintf(s->avctx, "final mv:%d %d\n", mx, my);

                        fill_rectangle(h->mvd_cache[list][ scan8[0] + 16*i ], 4, 2, 8, pack16to32(mx-mpx,my-mpy), 4);
                        fill_rectangle(h->mv_cache[list][ scan8[0] + 16*i ], 4, 2, 8, pack16to32(mx,my), 4);
                    }else{
                        fill_rectangle(h->mvd_cache[list][ scan8[0] + 16*i ], 4, 2, 8, 0, 4);
                        fill_rectangle(h-> mv_cache[list][ scan8[0] + 16*i ], 4, 2, 8, 0, 4);
                    }
                }
            }
        }else{
            assert(IS_8X16(mb_type));
            for(list=0; list<h->list_count; list++){
                    for(i=0; i<2; i++){
                        if(IS_DIR(mb_type, i, list)){ //FIXME optimize
                            int ref;
                            if(h->ref_count[list] > 1){
                                ref= decode_cabac_mb_ref( h, list, 4*i );
                                if(ref >= (unsigned)h->ref_count[list]){
                                    av_log(s->avctx, AV_LOG_ERROR, "Reference %d >= %d\n", ref, h->ref_count[list]);
                                    return -1;
                                }
                            }else
                                ref=0;
                            fill_rectangle(&h->ref_cache[list][ scan8[0] + 2*i ], 2, 4, 8, ref, 1);
                        }else
                            fill_rectangle(&h->ref_cache[list][ scan8[0] + 2*i ], 2, 4, 8, (LIST_NOT_USED&0xFF), 1);
                    }
            }
            for(list=0; list<h->list_count; list++){
                for(i=0; i<2; i++){
                    if(IS_DIR(mb_type, i, list)){
                        pred_8x16_motion(h, i*4, list, h->ref_cache[list][ scan8[0] + 2*i ], &mpx, &mpy);
                        mx = mpx + decode_cabac_mb_mvd( h, list, 4*i, 0 );
                        my = mpy + decode_cabac_mb_mvd( h, list, 4*i, 1 );

                        tprintf(s->avctx, "final mv:%d %d\n", mx, my);
                        fill_rectangle(h->mvd_cache[list][ scan8[0] + 2*i ], 2, 4, 8, pack16to32(mx-mpx,my-mpy), 4);
                        fill_rectangle(h->mv_cache[list][ scan8[0] + 2*i ], 2, 4, 8, pack16to32(mx,my), 4);
                    }else{
                        fill_rectangle(h->mvd_cache[list][ scan8[0] + 2*i ], 2, 4, 8, 0, 4);
                        fill_rectangle(h-> mv_cache[list][ scan8[0] + 2*i ], 2, 4, 8, 0, 4);
                    }
                }
            }
        }
    }

   if( IS_INTER( mb_type ) ) {
        h->chroma_pred_mode_table[mb_xy] = 0;
        write_back_motion( h, mb_type );
   }

    if( !IS_INTRA16x16( mb_type ) ) {
        cbp  = decode_cabac_mb_cbp_luma( h );
        if(CHROMA)
            cbp |= decode_cabac_mb_cbp_chroma( h ) << 4;
    }

    h->cbp_table[mb_xy] = h->cbp = cbp;

    if( dct8x8_allowed && (cbp&15) && !IS_INTRA( mb_type ) ) {
        if( decode_cabac_mb_transform_size( h ) )
            mb_type |= MB_TYPE_8x8DCT;
    }
    s->current_picture.mb_type[mb_xy]= mb_type;

    if( cbp || IS_INTRA16x16( mb_type ) ) {
        const uint8_t *scan, *scan8x8, *dc_scan;
        const uint32_t *qmul;
        int dqp;

        if(IS_INTERLACED(mb_type)){
            scan8x8= s->qscale ? h->field_scan8x8 : h->field_scan8x8_q0;
            scan= s->qscale ? h->field_scan : h->field_scan_q0;
            dc_scan= luma_dc_field_scan;
        }else{
            scan8x8= s->qscale ? h->zigzag_scan8x8 : h->zigzag_scan8x8_q0;
            scan= s->qscale ? h->zigzag_scan : h->zigzag_scan_q0;
            dc_scan= luma_dc_zigzag_scan;
        }

        h->last_qscale_diff = dqp = decode_cabac_mb_dqp( h );
        if( dqp == INT_MIN ){
            av_log(h->s.avctx, AV_LOG_ERROR, "cabac decode of qscale diff failed at %d %d\n", s->mb_x, s->mb_y);
            return -1;
        }
        s->qscale += dqp;
        if(((unsigned)s->qscale) > 51){
            if(s->qscale<0) s->qscale+= 52;
            else            s->qscale-= 52;
        }
        h->chroma_qp[0] = get_chroma_qp(h, 0, s->qscale);
        h->chroma_qp[1] = get_chroma_qp(h, 1, s->qscale);

        if( IS_INTRA16x16( mb_type ) ) {
            int i;
            //av_log( s->avctx, AV_LOG_ERROR, "INTRA16x16 DC\n" );
            decode_cabac_residual( h, h->mb, 0, 0, dc_scan, NULL, 16);

            if( cbp&15 ) {
                qmul = h->dequant4_coeff[0][s->qscale];
                for( i = 0; i < 16; i++ ) {
                    //av_log( s->avctx, AV_LOG_ERROR, "INTRA16x16 AC:%d\n", i );
                    decode_cabac_residual(h, h->mb + 16*i, 1, i, scan + 1, qmul, 15);
                }
            } else {
                fill_rectangle(&h->non_zero_count_cache[scan8[0]], 4, 4, 8, 0, 1);
            }
        } else {
            int i8x8, i4x4;
            for( i8x8 = 0; i8x8 < 4; i8x8++ ) {
                if( cbp & (1<<i8x8) ) {
                    if( IS_8x8DCT(mb_type) ) {
                        decode_cabac_residual(h, h->mb + 64*i8x8, 5, 4*i8x8,
                            scan8x8, h->dequant8_coeff[IS_INTRA( mb_type ) ? 0:1][s->qscale], 64);
                    } else {
                        qmul = h->dequant4_coeff[IS_INTRA( mb_type ) ? 0:3][s->qscale];
                        for( i4x4 = 0; i4x4 < 4; i4x4++ ) {
                            const int index = 4*i8x8 + i4x4;
                            //av_log( s->avctx, AV_LOG_ERROR, "Luma4x4: %d\n", index );
//START_TIMER
                            decode_cabac_residual(h, h->mb + 16*index, 2, index, scan, qmul, 16);
//STOP_TIMER("decode_residual")
                        }
                    }
                } else {
                    uint8_t * const nnz= &h->non_zero_count_cache[ scan8[4*i8x8] ];
                    nnz[0] = nnz[1] = nnz[8] = nnz[9] = 0;
                }
            }
        }

        if( cbp&0x30 ){
            int c;
            for( c = 0; c < 2; c++ ) {
                //av_log( s->avctx, AV_LOG_ERROR, "INTRA C%d-DC\n",c );
                decode_cabac_residual(h, h->mb + 256 + 16*4*c, 3, c, chroma_dc_scan, NULL, 4);
            }
        }

        if( cbp&0x20 ) {
            int c, i;
            for( c = 0; c < 2; c++ ) {
                qmul = h->dequant4_coeff[c+1+(IS_INTRA( mb_type ) ? 0:3)][h->chroma_qp[c]];
                for( i = 0; i < 4; i++ ) {
                    const int index = 16 + 4 * c + i;
                    //av_log( s->avctx, AV_LOG_ERROR, "INTRA C%d-AC %d\n",c, index - 16 );
                    decode_cabac_residual(h, h->mb + 16*index, 4, index, scan + 1, qmul, 15);
                }
            }
        } else {
            uint8_t * const nnz= &h->non_zero_count_cache[0];
            nnz[ scan8[16]+0 ] = nnz[ scan8[16]+1 ] =nnz[ scan8[16]+8 ] =nnz[ scan8[16]+9 ] =
            nnz[ scan8[20]+0 ] = nnz[ scan8[20]+1 ] =nnz[ scan8[20]+8 ] =nnz[ scan8[20]+9 ] = 0;
        }
    } else {
        uint8_t * const nnz= &h->non_zero_count_cache[0];
        fill_rectangle(&nnz[scan8[0]], 4, 4, 8, 0, 1);
        nnz[ scan8[16]+0 ] = nnz[ scan8[16]+1 ] =nnz[ scan8[16]+8 ] =nnz[ scan8[16]+9 ] =
        nnz[ scan8[20]+0 ] = nnz[ scan8[20]+1 ] =nnz[ scan8[20]+8 ] =nnz[ scan8[20]+9 ] = 0;
        h->last_qscale_diff = 0;
    }

    s->current_picture.qscale_table[mb_xy]= s->qscale;
    write_back_non_zero_count(h);

    if(MB_MBAFF){
        h->ref_count[0] >>= 1;
        h->ref_count[1] >>= 1;
    }

    return 0;
}

static int decode_slice(struct AVCodecContext *avctx, void *arg){
    H264Context *h = *(void**)arg;
    MpegEncContext * const s = &h->s;
    const int part_mask= s->partitioned_frame ? (AC_END|AC_ERROR) : 0x7F;

    s->mb_skip_run= -1;

    h->is_complex = FRAME_MBAFF || s->picture_structure != PICT_FRAME || s->codec_id != CODEC_ID_H264 ||
                    (CONFIG_GRAY && (s->flags&CODEC_FLAG_GRAY));

    if( h->pps.cabac ) {
        int i;

        /* realign */
        align_get_bits( &s->gb );

        /* init cabac */
        ff_init_cabac_states( &h->cabac);
        ff_init_cabac_decoder( &h->cabac,
                               s->gb.buffer + get_bits_count(&s->gb)/8,
                               (get_bits_left(&s->gb) + 7)/8);
        /* calculate pre-state */
        for( i= 0; i < 460; i++ ) {
            int pre;
            if( h->slice_type_nos == FF_I_TYPE )
                pre = av_clip( ((cabac_context_init_I[i][0] * s->qscale) >>4 ) + cabac_context_init_I[i][1], 1, 126 );
            else
                pre = av_clip( ((cabac_context_init_PB[h->cabac_init_idc][i][0] * s->qscale) >>4 ) + cabac_context_init_PB[h->cabac_init_idc][i][1], 1, 126 );

            if( pre <= 63 )
                h->cabac_state[i] = 2 * ( 63 - pre ) + 0;
            else
                h->cabac_state[i] = 2 * ( pre - 64 ) + 1;
        }

        for(;;){
//START_TIMER
            int ret = decode_mb_cabac(h);
            int eos;
//STOP_TIMER("decode_mb_cabac")

            if(ret>=0) ff_h264_hl_decode_mb(h);

            if( ret >= 0 && FRAME_MBAFF ) { //FIXME optimal? or let mb_decode decode 16x32 ?
                s->mb_y++;

                ret = decode_mb_cabac(h);

                if(ret>=0) ff_h264_hl_decode_mb(h);
                s->mb_y--;
            }
            eos = get_cabac_terminate( &h->cabac );

            if( ret < 0 || h->cabac.bytestream > h->cabac.bytestream_end + 2) {
                av_log(h->s.avctx, AV_LOG_ERROR, "error while decoding MB %d %d, bytestream (%td)\n", s->mb_x, s->mb_y, h->cabac.bytestream_end - h->cabac.bytestream);
                ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, (AC_ERROR|DC_ERROR|MV_ERROR)&part_mask);
                return -1;
            }

            if( ++s->mb_x >= s->mb_width ) {
                s->mb_x = 0;
                ff_draw_horiz_band(s, 16*s->mb_y, 16);
                ++s->mb_y;
                if(FIELD_OR_MBAFF_PICTURE) {
                    ++s->mb_y;
                }
            }

            if( eos || s->mb_y >= s->mb_height ) {
                tprintf(s->avctx, "slice end %d %d\n", get_bits_count(&s->gb), s->gb.size_in_bits);
                ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, (AC_END|DC_END|MV_END)&part_mask);
                return 0;
            }
        }

    } else {
        for(;;){
            int ret = ff_h264_decode_mb_cavlc(h);

            if(ret>=0) ff_h264_hl_decode_mb(h);

            if(ret>=0 && FRAME_MBAFF){ //FIXME optimal? or let mb_decode decode 16x32 ?
                s->mb_y++;
                ret = ff_h264_decode_mb_cavlc(h);

                if(ret>=0) ff_h264_hl_decode_mb(h);
                s->mb_y--;
            }

            if(ret<0){
                av_log(h->s.avctx, AV_LOG_ERROR, "error while decoding MB %d %d\n", s->mb_x, s->mb_y);
                ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, (AC_ERROR|DC_ERROR|MV_ERROR)&part_mask);

                return -1;
            }

            if(++s->mb_x >= s->mb_width){
                s->mb_x=0;
                ff_draw_horiz_band(s, 16*s->mb_y, 16);
                ++s->mb_y;
                if(FIELD_OR_MBAFF_PICTURE) {
                    ++s->mb_y;
                }
                if(s->mb_y >= s->mb_height){
                    tprintf(s->avctx, "slice end %d %d\n", get_bits_count(&s->gb), s->gb.size_in_bits);

                    if(get_bits_count(&s->gb) == s->gb.size_in_bits ) {
                        ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, (AC_END|DC_END|MV_END)&part_mask);

                        return 0;
                    }else{
                        ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, (AC_END|DC_END|MV_END)&part_mask);

                        return -1;
                    }
                }
            }

            if(get_bits_count(&s->gb) >= s->gb.size_in_bits && s->mb_skip_run<=0){
                tprintf(s->avctx, "slice end %d %d\n", get_bits_count(&s->gb), s->gb.size_in_bits);
                if(get_bits_count(&s->gb) == s->gb.size_in_bits ){
                    ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, (AC_END|DC_END|MV_END)&part_mask);

                    return 0;
                }else{
                    ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, (AC_ERROR|DC_ERROR|MV_ERROR)&part_mask);

                    return -1;
                }
            }
        }
    }

#if 0
    for(;s->mb_y < s->mb_height; s->mb_y++){
        for(;s->mb_x < s->mb_width; s->mb_x++){
            int ret= decode_mb(h);

            ff_h264_hl_decode_mb(h);

            if(ret<0){
                av_log(s->avctx, AV_LOG_ERROR, "error while decoding MB %d %d\n", s->mb_x, s->mb_y);
                ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, (AC_ERROR|DC_ERROR|MV_ERROR)&part_mask);

                return -1;
            }

            if(++s->mb_x >= s->mb_width){
                s->mb_x=0;
                if(++s->mb_y >= s->mb_height){
                    if(get_bits_count(s->gb) == s->gb.size_in_bits){
                        ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, (AC_END|DC_END|MV_END)&part_mask);

                        return 0;
                    }else{
                        ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, (AC_END|DC_END|MV_END)&part_mask);

                        return -1;
                    }
                }
            }

            if(get_bits_count(s->?gb) >= s->gb?.size_in_bits){
                if(get_bits_count(s->gb) == s->gb.size_in_bits){
                    ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, (AC_END|DC_END|MV_END)&part_mask);

                    return 0;
                }else{
                    ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, (AC_ERROR|DC_ERROR|MV_ERROR)&part_mask);

                    return -1;
                }
            }
        }
        s->mb_x=0;
        ff_draw_horiz_band(s, 16*s->mb_y, 16);
    }
#endif
    return -1; //not reached
}

/**
 * Call decode_slice() for each context.
 *
 * @param h h264 master context
 * @param context_count number of contexts to execute
 */
static void execute_decode_slices(H264Context *h, int context_count){
    MpegEncContext * const s = &h->s;
    AVCodecContext * const avctx= s->avctx;
    H264Context *hx;
    int i;

    if (s->avctx->hwaccel)
        return;
    if(s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU)
        return;
    if(context_count == 1) {
        decode_slice(avctx, &h);
    } else {
        for(i = 1; i < context_count; i++) {
            hx = h->thread_context[i];
            hx->s.error_recognition = avctx->error_recognition;
            hx->s.error_count = 0;
        }

        avctx->execute(avctx, (void *)decode_slice,
                       h->thread_context, NULL, context_count, sizeof(void*));

        /* pull back stuff from slices to master context */
        hx = h->thread_context[context_count - 1];
        s->mb_x = hx->s.mb_x;
        s->mb_y = hx->s.mb_y;
        s->dropable = hx->s.dropable;
        s->picture_structure = hx->s.picture_structure;
        for(i = 1; i < context_count; i++)
            h->s.error_count += h->thread_context[i]->s.error_count;
    }
}


static int decode_nal_units(H264Context *h, const uint8_t *buf, int buf_size){
    MpegEncContext * const s = &h->s;
    AVCodecContext * const avctx= s->avctx;
    int buf_index=0;
    H264Context *hx; ///< thread context
    int context_count = 0;
    int next_avc= h->is_avc ? 0 : buf_size;

    h->max_contexts = avctx->thread_count;
#if 0
    int i;
    for(i=0; i<50; i++){
        av_log(NULL, AV_LOG_ERROR,"%02X ", buf[i]);
    }
#endif
    if(!(s->flags2 & CODEC_FLAG2_CHUNKS)){
        h->current_slice = 0;
        if (!s->first_field)
            s->current_picture_ptr= NULL;
        ff_h264_reset_sei(h);
    }

    for(;;){
        int consumed;
        int dst_length;
        int bit_length;
        const uint8_t *ptr;
        int i, nalsize = 0;
        int err;

        if(buf_index >= next_avc) {
            if(buf_index >= buf_size) break;
            nalsize = 0;
            for(i = 0; i < h->nal_length_size; i++)
                nalsize = (nalsize << 8) | buf[buf_index++];
            if(nalsize <= 1 || nalsize > buf_size - buf_index){
                if(nalsize == 1){
                    buf_index++;
                    continue;
                }else{
                    av_log(h->s.avctx, AV_LOG_ERROR, "AVC: nal size %d\n", nalsize);
                    break;
                }
            }
            next_avc= buf_index + nalsize;
        } else {
            // start code prefix search
            for(; buf_index + 3 < next_avc; buf_index++){
                // This should always succeed in the first iteration.
                if(buf[buf_index] == 0 && buf[buf_index+1] == 0 && buf[buf_index+2] == 1)
                    break;
            }

            if(buf_index+3 >= buf_size) break;

            buf_index+=3;
            if(buf_index >= next_avc) continue;
        }

        hx = h->thread_context[context_count];

        ptr= ff_h264_decode_nal(hx, buf + buf_index, &dst_length, &consumed, next_avc - buf_index);
        if (ptr==NULL || dst_length < 0){
            return -1;
        }
        while(ptr[dst_length - 1] == 0 && dst_length > 0)
            dst_length--;
        bit_length= !dst_length ? 0 : (8*dst_length - ff_h264_decode_rbsp_trailing(h, ptr + dst_length - 1));

        if(s->avctx->debug&FF_DEBUG_STARTCODE){
            av_log(h->s.avctx, AV_LOG_DEBUG, "NAL %d at %d/%d length %d\n", hx->nal_unit_type, buf_index, buf_size, dst_length);
        }

        if (h->is_avc && (nalsize != consumed) && nalsize){
            av_log(h->s.avctx, AV_LOG_DEBUG, "AVC: Consumed only %d bytes instead of %d\n", consumed, nalsize);
        }

        buf_index += consumed;

        if(  (s->hurry_up == 1 && h->nal_ref_idc  == 0) //FIXME do not discard SEI id
           ||(avctx->skip_frame >= AVDISCARD_NONREF && h->nal_ref_idc  == 0))
            continue;

      again:
        err = 0;
        switch(hx->nal_unit_type){
        case NAL_IDR_SLICE:
            if (h->nal_unit_type != NAL_IDR_SLICE) {
                av_log(h->s.avctx, AV_LOG_ERROR, "Invalid mix of idr and non-idr slices");
                return -1;
            }
            idr(h); //FIXME ensure we don't loose some frames if there is reordering
        case NAL_SLICE:
            init_get_bits(&hx->s.gb, ptr, bit_length);
            hx->intra_gb_ptr=
            hx->inter_gb_ptr= &hx->s.gb;
            hx->s.data_partitioning = 0;

            if((err = decode_slice_header(hx, h)))
               break;

            if (s->avctx->hwaccel && h->current_slice == 1) {
                if (s->avctx->hwaccel->start_frame(s->avctx, NULL, 0) < 0)
                    return -1;
            }

            s->current_picture_ptr->key_frame |=
                    (hx->nal_unit_type == NAL_IDR_SLICE) ||
                    (h->sei_recovery_frame_cnt >= 0);
            if(hx->redundant_pic_count==0 && hx->s.hurry_up < 5
               && (avctx->skip_frame < AVDISCARD_NONREF || hx->nal_ref_idc)
               && (avctx->skip_frame < AVDISCARD_BIDIR  || hx->slice_type_nos!=FF_B_TYPE)
               && (avctx->skip_frame < AVDISCARD_NONKEY || hx->slice_type_nos==FF_I_TYPE)
               && avctx->skip_frame < AVDISCARD_ALL){
                if(avctx->hwaccel) {
                    if (avctx->hwaccel->decode_slice(avctx, &buf[buf_index - consumed], consumed) < 0)
                        return -1;
                }else
                if(CONFIG_H264_VDPAU_DECODER && s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU){
                    static const uint8_t start_code[] = {0x00, 0x00, 0x01};
                    ff_vdpau_add_data_chunk(s, start_code, sizeof(start_code));
                    ff_vdpau_add_data_chunk(s, &buf[buf_index - consumed], consumed );
                }else
                    context_count++;
            }
            break;
        case NAL_DPA:
            init_get_bits(&hx->s.gb, ptr, bit_length);
            hx->intra_gb_ptr=
            hx->inter_gb_ptr= NULL;

            if ((err = decode_slice_header(hx, h)) < 0)
                break;

            hx->s.data_partitioning = 1;

            break;
        case NAL_DPB:
            init_get_bits(&hx->intra_gb, ptr, bit_length);
            hx->intra_gb_ptr= &hx->intra_gb;
            break;
        case NAL_DPC:
            init_get_bits(&hx->inter_gb, ptr, bit_length);
            hx->inter_gb_ptr= &hx->inter_gb;

            if(hx->redundant_pic_count==0 && hx->intra_gb_ptr && hx->s.data_partitioning
               && s->context_initialized
               && s->hurry_up < 5
               && (avctx->skip_frame < AVDISCARD_NONREF || hx->nal_ref_idc)
               && (avctx->skip_frame < AVDISCARD_BIDIR  || hx->slice_type_nos!=FF_B_TYPE)
               && (avctx->skip_frame < AVDISCARD_NONKEY || hx->slice_type_nos==FF_I_TYPE)
               && avctx->skip_frame < AVDISCARD_ALL)
                context_count++;
            break;
        case NAL_SEI:
            init_get_bits(&s->gb, ptr, bit_length);
            ff_h264_decode_sei(h);
            break;
        case NAL_SPS:
            init_get_bits(&s->gb, ptr, bit_length);
            ff_h264_decode_seq_parameter_set(h);

            if(s->flags& CODEC_FLAG_LOW_DELAY)
                s->low_delay=1;

            if(avctx->has_b_frames < 2)
                avctx->has_b_frames= !s->low_delay;
            break;
        case NAL_PPS:
            init_get_bits(&s->gb, ptr, bit_length);

            ff_h264_decode_picture_parameter_set(h, bit_length);

            break;
        case NAL_AUD:
        case NAL_END_SEQUENCE:
        case NAL_END_STREAM:
        case NAL_FILLER_DATA:
        case NAL_SPS_EXT:
        case NAL_AUXILIARY_SLICE:
            break;
        default:
            av_log(avctx, AV_LOG_DEBUG, "Unknown NAL code: %d (%d bits)\n", hx->nal_unit_type, bit_length);
        }

        if(context_count == h->max_contexts) {
            execute_decode_slices(h, context_count);
            context_count = 0;
        }

        if (err < 0)
            av_log(h->s.avctx, AV_LOG_ERROR, "decode_slice_header error\n");
        else if(err == 1) {
            /* Slice could not be decoded in parallel mode, copy down
             * NAL unit stuff to context 0 and restart. Note that
             * rbsp_buffer is not transferred, but since we no longer
             * run in parallel mode this should not be an issue. */
            h->nal_unit_type = hx->nal_unit_type;
            h->nal_ref_idc   = hx->nal_ref_idc;
            hx = h;
            goto again;
        }
    }
    if(context_count)
        execute_decode_slices(h, context_count);
    return buf_index;
}

/**
 * returns the number of bytes consumed for building the current frame
 */
static int get_consumed_bytes(MpegEncContext *s, int pos, int buf_size){
        if(pos==0) pos=1; //avoid infinite loops (i doubt that is needed but ...)
        if(pos+10>buf_size) pos=buf_size; // oops ;)

        return pos;
}

static int decode_frame(AVCodecContext *avctx,
                             void *data, int *data_size,
                             AVPacket *avpkt)
{
    const uint8_t *buf = avpkt->data;
    int buf_size = avpkt->size;
    H264Context *h = avctx->priv_data;
    MpegEncContext *s = &h->s;
    AVFrame *pict = data;
    int buf_index;

    s->flags= avctx->flags;
    s->flags2= avctx->flags2;

   /* end of stream, output what is still in the buffers */
    if (buf_size == 0) {
        Picture *out;
        int i, out_idx;

//FIXME factorize this with the output code below
        out = h->delayed_pic[0];
        out_idx = 0;
        for(i=1; h->delayed_pic[i] && !h->delayed_pic[i]->key_frame && !h->delayed_pic[i]->mmco_reset; i++)
            if(h->delayed_pic[i]->poc < out->poc){
                out = h->delayed_pic[i];
                out_idx = i;
            }

        for(i=out_idx; h->delayed_pic[i]; i++)
            h->delayed_pic[i] = h->delayed_pic[i+1];

        if(out){
            *data_size = sizeof(AVFrame);
            *pict= *(AVFrame*)out;
        }

        return 0;
    }

    if(h->is_avc && !h->got_avcC) {
        int i, cnt, nalsize;
        unsigned char *p = avctx->extradata;
        if(avctx->extradata_size < 7) {
            av_log(avctx, AV_LOG_ERROR, "avcC too short\n");
            return -1;
        }
        if(*p != 1) {
            av_log(avctx, AV_LOG_ERROR, "Unknown avcC version %d\n", *p);
            return -1;
        }
        /* sps and pps in the avcC always have length coded with 2 bytes,
           so put a fake nal_length_size = 2 while parsing them */
        h->nal_length_size = 2;
        // Decode sps from avcC
        cnt = *(p+5) & 0x1f; // Number of sps
        p += 6;
        for (i = 0; i < cnt; i++) {
            nalsize = AV_RB16(p) + 2;
            if(decode_nal_units(h, p, nalsize) < 0) {
                av_log(avctx, AV_LOG_ERROR, "Decoding sps %d from avcC failed\n", i);
                return -1;
            }
            p += nalsize;
        }
        // Decode pps from avcC
        cnt = *(p++); // Number of pps
        for (i = 0; i < cnt; i++) {
            nalsize = AV_RB16(p) + 2;
            if(decode_nal_units(h, p, nalsize)  != nalsize) {
                av_log(avctx, AV_LOG_ERROR, "Decoding pps %d from avcC failed\n", i);
                return -1;
            }
            p += nalsize;
        }
        // Now store right nal length size, that will be use to parse all other nals
        h->nal_length_size = ((*(((char*)(avctx->extradata))+4))&0x03)+1;
        // Do not reparse avcC
        h->got_avcC = 1;
    }

    if(!h->got_avcC && !h->is_avc && s->avctx->extradata_size){
        if(decode_nal_units(h, s->avctx->extradata, s->avctx->extradata_size) < 0)
            return -1;
        h->got_avcC = 1;
    }

    buf_index=decode_nal_units(h, buf, buf_size);
    if(buf_index < 0)
        return -1;

    if(!(s->flags2 & CODEC_FLAG2_CHUNKS) && !s->current_picture_ptr){
        if (avctx->skip_frame >= AVDISCARD_NONREF || s->hurry_up) return 0;
        av_log(avctx, AV_LOG_ERROR, "no frame!\n");
        return -1;
    }

    if(!(s->flags2 & CODEC_FLAG2_CHUNKS) || (s->mb_y >= s->mb_height && s->mb_height)){
        Picture *out = s->current_picture_ptr;
        Picture *cur = s->current_picture_ptr;
        int i, pics, out_of_order, out_idx;

        field_end(h);

        if (cur->field_poc[0]==INT_MAX || cur->field_poc[1]==INT_MAX) {
            /* Wait for second field. */
            *data_size = 0;

        } else {
            cur->interlaced_frame = 0;
            cur->repeat_pict = 0;

            /* Signal interlacing information externally. */
            /* Prioritize picture timing SEI information over used decoding process if it exists. */

            if(h->sps.pic_struct_present_flag){
                switch (h->sei_pic_struct)
                {
                case SEI_PIC_STRUCT_FRAME:
                    break;
                case SEI_PIC_STRUCT_TOP_FIELD:
                case SEI_PIC_STRUCT_BOTTOM_FIELD:
                    cur->interlaced_frame = 1;
                    break;
                case SEI_PIC_STRUCT_TOP_BOTTOM:
                case SEI_PIC_STRUCT_BOTTOM_TOP:
                    if (FIELD_OR_MBAFF_PICTURE)
                        cur->interlaced_frame = 1;
                    else
                        // try to flag soft telecine progressive
                        cur->interlaced_frame = h->prev_interlaced_frame;
                    break;
                case SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
                case SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM:
                    // Signal the possibility of telecined film externally (pic_struct 5,6)
                    // From these hints, let the applications decide if they apply deinterlacing.
                    cur->repeat_pict = 1;
                    break;
                case SEI_PIC_STRUCT_FRAME_DOUBLING:
                    // Force progressive here, as doubling interlaced frame is a bad idea.
                    cur->repeat_pict = 2;
                    break;
                case SEI_PIC_STRUCT_FRAME_TRIPLING:
                    cur->repeat_pict = 4;
                    break;
                }

                if ((h->sei_ct_type & 3) && h->sei_pic_struct <= SEI_PIC_STRUCT_BOTTOM_TOP)
                    cur->interlaced_frame = (h->sei_ct_type & (1<<1)) != 0;
            }else{
                /* Derive interlacing flag from used decoding process. */
                cur->interlaced_frame = FIELD_OR_MBAFF_PICTURE;
            }
            h->prev_interlaced_frame = cur->interlaced_frame;

            if (cur->field_poc[0] != cur->field_poc[1]){
                /* Derive top_field_first from field pocs. */
                cur->top_field_first = cur->field_poc[0] < cur->field_poc[1];
            }else{
                if(cur->interlaced_frame || h->sps.pic_struct_present_flag){
                    /* Use picture timing SEI information. Even if it is a information of a past frame, better than nothing. */
                    if(h->sei_pic_struct == SEI_PIC_STRUCT_TOP_BOTTOM
                      || h->sei_pic_struct == SEI_PIC_STRUCT_TOP_BOTTOM_TOP)
                        cur->top_field_first = 1;
                    else
                        cur->top_field_first = 0;
                }else{
                    /* Most likely progressive */
                    cur->top_field_first = 0;
                }
            }

        //FIXME do something with unavailable reference frames

            /* Sort B-frames into display order */

            if(h->sps.bitstream_restriction_flag
               && s->avctx->has_b_frames < h->sps.num_reorder_frames){
                s->avctx->has_b_frames = h->sps.num_reorder_frames;
                s->low_delay = 0;
            }

            if(   s->avctx->strict_std_compliance >= FF_COMPLIANCE_STRICT
               && !h->sps.bitstream_restriction_flag){
                s->avctx->has_b_frames= MAX_DELAYED_PIC_COUNT;
                s->low_delay= 0;
            }

            pics = 0;
            while(h->delayed_pic[pics]) pics++;

            assert(pics <= MAX_DELAYED_PIC_COUNT);

            h->delayed_pic[pics++] = cur;
            if(cur->reference == 0)
                cur->reference = DELAYED_PIC_REF;

            out = h->delayed_pic[0];
            out_idx = 0;
            for(i=1; h->delayed_pic[i] && !h->delayed_pic[i]->key_frame && !h->delayed_pic[i]->mmco_reset; i++)
                if(h->delayed_pic[i]->poc < out->poc){
                    out = h->delayed_pic[i];
                    out_idx = i;
                }
            if(s->avctx->has_b_frames == 0 && (h->delayed_pic[0]->key_frame || h->delayed_pic[0]->mmco_reset))
                h->outputed_poc= INT_MIN;
            out_of_order = out->poc < h->outputed_poc;

            if(h->sps.bitstream_restriction_flag && s->avctx->has_b_frames >= h->sps.num_reorder_frames)
                { }
            else if((out_of_order && pics-1 == s->avctx->has_b_frames && s->avctx->has_b_frames < MAX_DELAYED_PIC_COUNT)
               || (s->low_delay &&
                ((h->outputed_poc != INT_MIN && out->poc > h->outputed_poc + 2)
                 || cur->pict_type == FF_B_TYPE)))
            {
                s->low_delay = 0;
                s->avctx->has_b_frames++;
            }

            if(out_of_order || pics > s->avctx->has_b_frames){
                out->reference &= ~DELAYED_PIC_REF;
                for(i=out_idx; h->delayed_pic[i]; i++)
                    h->delayed_pic[i] = h->delayed_pic[i+1];
            }
            if(!out_of_order && pics > s->avctx->has_b_frames){
                *data_size = sizeof(AVFrame);

                if(out_idx==0 && h->delayed_pic[0] && (h->delayed_pic[0]->key_frame || h->delayed_pic[0]->mmco_reset)) {
                    h->outputed_poc = INT_MIN;
                } else
                    h->outputed_poc = out->poc;
                *pict= *(AVFrame*)out;
            }else{
                av_log(avctx, AV_LOG_DEBUG, "no picture\n");
            }
        }
    }

    assert(pict->data[0] || !*data_size);
    ff_print_debug_info(s, pict);
//printf("out %d\n", (int)pict->data[0]);

    return get_consumed_bytes(s, buf_index, buf_size);
}
#if 0
static inline void fill_mb_avail(H264Context *h){
    MpegEncContext * const s = &h->s;
    const int mb_xy= s->mb_x + s->mb_y*s->mb_stride;

    if(s->mb_y){
        h->mb_avail[0]= s->mb_x                 && h->slice_table[mb_xy - s->mb_stride - 1] == h->slice_num;
        h->mb_avail[1]=                            h->slice_table[mb_xy - s->mb_stride    ] == h->slice_num;
        h->mb_avail[2]= s->mb_x+1 < s->mb_width && h->slice_table[mb_xy - s->mb_stride + 1] == h->slice_num;
    }else{
        h->mb_avail[0]=
        h->mb_avail[1]=
        h->mb_avail[2]= 0;
    }
    h->mb_avail[3]= s->mb_x && h->slice_table[mb_xy - 1] == h->slice_num;
    h->mb_avail[4]= 1; //FIXME move out
    h->mb_avail[5]= 0; //FIXME move out
}
#endif

#ifdef TEST
#undef printf
#undef random
#define COUNT 8000
#define SIZE (COUNT*40)
int main(void){
    int i;
    uint8_t temp[SIZE];
    PutBitContext pb;
    GetBitContext gb;
//    int int_temp[10000];
    DSPContext dsp;
    AVCodecContext avctx;

    dsputil_init(&dsp, &avctx);

    init_put_bits(&pb, temp, SIZE);
    printf("testing unsigned exp golomb\n");
    for(i=0; i<COUNT; i++){
        START_TIMER
        set_ue_golomb(&pb, i);
        STOP_TIMER("set_ue_golomb");
    }
    flush_put_bits(&pb);

    init_get_bits(&gb, temp, 8*SIZE);
    for(i=0; i<COUNT; i++){
        int j, s;

        s= show_bits(&gb, 24);

        START_TIMER
        j= get_ue_golomb(&gb);
        if(j != i){
            printf("mismatch! at %d (%d should be %d) bits:%6X\n", i, j, i, s);
//            return -1;
        }
        STOP_TIMER("get_ue_golomb");
    }


    init_put_bits(&pb, temp, SIZE);
    printf("testing signed exp golomb\n");
    for(i=0; i<COUNT; i++){
        START_TIMER
        set_se_golomb(&pb, i - COUNT/2);
        STOP_TIMER("set_se_golomb");
    }
    flush_put_bits(&pb);

    init_get_bits(&gb, temp, 8*SIZE);
    for(i=0; i<COUNT; i++){
        int j, s;

        s= show_bits(&gb, 24);

        START_TIMER
        j= get_se_golomb(&gb);
        if(j != i - COUNT/2){
            printf("mismatch! at %d (%d should be %d) bits:%6X\n", i, j, i, s);
//            return -1;
        }
        STOP_TIMER("get_se_golomb");
    }

#if 0
    printf("testing 4x4 (I)DCT\n");

    DCTELEM block[16];
    uint8_t src[16], ref[16];
    uint64_t error= 0, max_error=0;

    for(i=0; i<COUNT; i++){
        int j;
//        printf("%d %d %d\n", r1, r2, (r2-r1)*16);
        for(j=0; j<16; j++){
            ref[j]= random()%255;
            src[j]= random()%255;
        }

        h264_diff_dct_c(block, src, ref, 4);

        //normalize
        for(j=0; j<16; j++){
//            printf("%d ", block[j]);
            block[j]= block[j]*4;
            if(j&1) block[j]= (block[j]*4 + 2)/5;
            if(j&4) block[j]= (block[j]*4 + 2)/5;
        }
//        printf("\n");

        s->dsp.h264_idct_add(ref, block, 4);
/*        for(j=0; j<16; j++){
            printf("%d ", ref[j]);
        }
        printf("\n");*/

        for(j=0; j<16; j++){
            int diff= FFABS(src[j] - ref[j]);

            error+= diff*diff;
            max_error= FFMAX(max_error, diff);
        }
    }
    printf("error=%f max_error=%d\n", ((float)error)/COUNT/16, (int)max_error );
    printf("testing quantizer\n");
    for(qp=0; qp<52; qp++){
        for(i=0; i<16; i++)
            src1_block[i]= src2_block[i]= random()%255;

    }
    printf("Testing NAL layer\n");

    uint8_t bitstream[COUNT];
    uint8_t nal[COUNT*2];
    H264Context h;
    memset(&h, 0, sizeof(H264Context));

    for(i=0; i<COUNT; i++){
        int zeros= i;
        int nal_length;
        int consumed;
        int out_length;
        uint8_t *out;
        int j;

        for(j=0; j<COUNT; j++){
            bitstream[j]= (random() % 255) + 1;
        }

        for(j=0; j<zeros; j++){
            int pos= random() % COUNT;
            while(bitstream[pos] == 0){
                pos++;
                pos %= COUNT;
            }
            bitstream[pos]=0;
        }

        START_TIMER

        nal_length= encode_nal(&h, nal, bitstream, COUNT, COUNT*2);
        if(nal_length<0){
            printf("encoding failed\n");
            return -1;
        }

        out= ff_h264_decode_nal(&h, nal, &out_length, &consumed, nal_length);

        STOP_TIMER("NAL")

        if(out_length != COUNT){
            printf("incorrect length %d %d\n", out_length, COUNT);
            return -1;
        }

        if(consumed != nal_length){
            printf("incorrect consumed length %d %d\n", nal_length, consumed);
            return -1;
        }

        if(memcmp(bitstream, out, COUNT)){
            printf("mismatch\n");
            return -1;
        }
    }
#endif

    printf("Testing RBSP\n");


    return 0;
}
#endif /* TEST */


av_cold void ff_h264_free_context(H264Context *h)
{
    int i;

    free_tables(h); //FIXME cleanup init stuff perhaps

    for(i = 0; i < MAX_SPS_COUNT; i++)
        av_freep(h->sps_buffers + i);

    for(i = 0; i < MAX_PPS_COUNT; i++)
        av_freep(h->pps_buffers + i);
}

av_cold int ff_h264_decode_end(AVCodecContext *avctx)
{
    H264Context *h = avctx->priv_data;
    MpegEncContext *s = &h->s;

    ff_h264_free_context(h);

    MPV_common_end(s);

//    memset(h, 0, sizeof(H264Context));

    return 0;
}


AVCodec h264_decoder = {
    "h264",
    CODEC_TYPE_VIDEO,
    CODEC_ID_H264,
    sizeof(H264Context),
    ff_h264_decode_init,
    NULL,
    ff_h264_decode_end,
    decode_frame,
    /*CODEC_CAP_DRAW_HORIZ_BAND |*/ CODEC_CAP_DR1 | CODEC_CAP_DELAY,
    .flush= flush_dpb,
    .long_name = NULL_IF_CONFIG_SMALL("H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10"),
    .pix_fmts= ff_hwaccel_pixfmt_list_420,
};

#if CONFIG_H264_VDPAU_DECODER
AVCodec h264_vdpau_decoder = {
    "h264_vdpau",
    CODEC_TYPE_VIDEO,
    CODEC_ID_H264,
    sizeof(H264Context),
    ff_h264_decode_init,
    NULL,
    ff_h264_decode_end,
    decode_frame,
    CODEC_CAP_DR1 | CODEC_CAP_DELAY | CODEC_CAP_HWACCEL_VDPAU,
    .flush= flush_dpb,
    .long_name = NULL_IF_CONFIG_SMALL("H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 (VDPAU acceleration)"),
    .pix_fmts = (const enum PixelFormat[]){PIX_FMT_VDPAU_H264, PIX_FMT_NONE},
};
#endif