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FFmpeg/libavcodec/cavs.c

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  1. /*

  2.  * Chinese AVS video (AVS1-P2, JiZhun profile) decoder.

  3.  * Copyright (c) 2006  Stefan Gehrer <stefan.gehrer@gmx.de>

  4.  *

  5.  * This library is free software; you can redistribute it and/or

  6.  * modify it under the terms of the GNU Lesser General Public

  7.  * License as published by the Free Software Foundation; either

  8.  * version 2 of the License, or (at your option) any later version.

  9.  *

  10.  * This library is distributed in the hope that it will be useful,

  11.  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  12.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  13.  * Lesser General Public License for more details.

  14.  *

  15.  * You should have received a copy of the GNU Lesser General Public

  16.  * License along with this library; if not, write to the Free Software

  17.  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

  18.  */

  19. 

  20. #include "avcodec.h"

  21. #include "bitstream.h"

  22. #include "golomb.h"

  23. #include "mpegvideo.h"

  24. #include "cavsdata.h"

  25. 

  26. typedef struct {

  27.     MpegEncContext s;

  28.     Picture picture; //currently decoded frame

  29.     Picture DPB[2];  //reference frames

  30.     int dist[2];     //temporal distances from current frame to ref frames

  31.     int profile, level;

  32.     int aspect_ratio;

  33.     int mb_width, mb_height;

  34.     int pic_type;

  35.     int progressive;

  36.     int pic_structure;

  37.     int skip_mode_flag;

  38.     int loop_filter_disable;

  39.     int alpha_offset, beta_offset;

  40.     int ref_flag;

  41.     int mbx, mby;

  42.     int flags;

  43.     int stc;

  44.     uint8_t *cy, *cu, *cv;

  45.     int left_qp;

  46.     uint8_t *top_qp;

  47. 

  48.     /* mv motion vector cache

  49.        0:    D3  B2  B3  C2

  50.        4:    A1  X0  X1   -

  51.        8:    A3  X2  X3   -

  52. 

  53.        X are the vectors in the current macroblock (5,6,9,10)

  54.        A is the macroblock to the left (4,8)

  55.        B is the macroblock to the top (1,2)

  56.        C is the macroblock to the top-right (3)

  57.        D is the macroblock to the top-left (0)

  58. 

  59.        the same is repeated for backward motion vectors */

  60.     vector_t mv[2*4*3];

  61.     vector_t *top_mv[2];

  62.     vector_t *col_mv;

  63. 

  64.     /* luma pred mode cache

  65.        0:    --  B2  B3

  66.        3:    A1  X0  X1

  67.        6:    A3  X2  X3   */

  68.     int pred_mode_Y[3*3];

  69.     int *top_pred_Y;

  70.     int l_stride, c_stride;

  71.     int luma_scan[4];

  72.     int qp;

  73.     int qp_fixed;

  74.     int cbp;

  75. 

  76.     /* intra prediction is done with un-deblocked samples

  77.      they are saved here before deblocking the MB  */

  78.     uint8_t *top_border_y, *top_border_u, *top_border_v;

  79.     uint8_t left_border_y[16], left_border_u[8], left_border_v[8];

  80.     uint8_t topleft_border_y, topleft_border_u, topleft_border_v;

  81. 

  82.     void (*intra_pred_l[8])(uint8_t *d,uint8_t *top,uint8_t *left,int stride);

  83.     void (*intra_pred_c[7])(uint8_t *d,uint8_t *top,uint8_t *left,int stride);

  84.     uint8_t *col_type_base;

  85.     uint8_t *col_type;

  86.     int sym_factor;

  87.     int direct_den[2];

  88.     int scale_den[2];

  89.     int got_keyframe;

  90. } AVSContext;

  91. 

  92. /*****************************************************************************

  93.  *

  94.  * in-loop deblocking filter

  95.  *

  96.  ****************************************************************************/

  97. 

  98. static inline int get_bs_p(vector_t *mvP, vector_t *mvQ) {

  99.     if((mvP->ref == REF_INTRA) || (mvQ->ref == REF_INTRA))

  100.         return 2;

  101.     if(mvP->ref != mvQ->ref)

  102.         return 1;

  103.     if( (abs(mvP->x - mvQ->x) >= 4) ||  (abs(mvP->y - mvQ->y) >= 4) )

  104.         return 1;

  105.     return 0;

  106. }

  107. 

  108. static inline int get_bs_b(vector_t *mvP, vector_t *mvQ) {

  109.     if((mvP->ref == REF_INTRA) || (mvQ->ref == REF_INTRA)) {

  110.         return 2;

  111.     } else {

  112.         vector_t *mvPbw = mvP + MV_BWD_OFFS;

  113.         vector_t *mvQbw = mvQ + MV_BWD_OFFS;

  114.         if( (abs(  mvP->x -   mvQ->x) >= 4) ||

  115.             (abs(  mvP->y -   mvQ->y) >= 4) ||

  116.             (abs(mvPbw->x - mvQbw->x) >= 4) ||

  117.             (abs(mvPbw->y - mvQbw->y) >= 4) )

  118.             return 1;

  119.     }

  120.     return 0;

  121. }

  122. 

  123. /* boundary strength (bs) mapping:

  124.  *

  125.  * --4---5--

  126.  * 0   2   |

  127.  * | 6 | 7 |

  128.  * 1   3   |

  129.  * ---------

  130.  *

  131.  */

  132. 

  133. #define SET_PARAMS                                            \

  134.     alpha = alpha_tab[clip(qp_avg + h->alpha_offset,0,63)];   \

  135.     beta  =  beta_tab[clip(qp_avg + h->beta_offset, 0,63)];   \

  136.     tc    =    tc_tab[clip(qp_avg + h->alpha_offset,0,63)];

  137. 

  138. static void filter_mb(AVSContext *h, enum mb_t mb_type) {

  139.     uint8_t bs[8];

  140.     int qp_avg, alpha, beta, tc;

  141.     int i;

  142. 

  143.     /* save un-deblocked lines */

  144.     h->topleft_border_y = h->top_border_y[h->mbx*16+15];

  145.     h->topleft_border_u = h->top_border_u[h->mbx*8+7];

  146.     h->topleft_border_v = h->top_border_v[h->mbx*8+7];

  147.     memcpy(&h->top_border_y[h->mbx*16], h->cy + 15* h->l_stride,16);

  148.     memcpy(&h->top_border_u[h->mbx* 8], h->cu +  7* h->c_stride,8);

  149.     memcpy(&h->top_border_v[h->mbx* 8], h->cv +  7* h->c_stride,8);

  150.     for(i=0;i<8;i++) {

  151.         h->left_border_y[i*2+0] = *(h->cy + 15 + (i*2+0)*h->l_stride);

  152.         h->left_border_y[i*2+1] = *(h->cy + 15 + (i*2+1)*h->l_stride);

  153.         h->left_border_u[i] = *(h->cu + 7 + i*h->c_stride);

  154.         h->left_border_v[i] = *(h->cv + 7 + i*h->c_stride);

  155.     }

  156.     if(!h->loop_filter_disable) {

  157.         /* clear bs */

  158.         *((uint64_t *)bs) = 0;

  159.         /* determine bs */

  160.         switch(mb_type) {

  161.         case I_8X8:

  162.             *((uint64_t *)bs) = 0x0202020202020202ULL;

  163.             break;

  164.         case P_8X8:

  165.         case P_8X16:

  166.             bs[2] = get_bs_p(&h->mv[MV_FWD_X0], &h->mv[MV_FWD_X1]);

  167.             bs[3] = get_bs_p(&h->mv[MV_FWD_X2], &h->mv[MV_FWD_X3]);

  168.         case P_16X8:

  169.             bs[6] = get_bs_p(&h->mv[MV_FWD_X0], &h->mv[MV_FWD_X2]);

  170.             bs[7] = get_bs_p(&h->mv[MV_FWD_X1], &h->mv[MV_FWD_X3]);

  171.         case P_16X16:

  172.         case P_SKIP:

  173.             bs[0] = get_bs_p(&h->mv[MV_FWD_A1], &h->mv[MV_FWD_X0]);

  174.             bs[1] = get_bs_p(&h->mv[MV_FWD_A3], &h->mv[MV_FWD_X2]);

  175.             bs[4] = get_bs_p(&h->mv[MV_FWD_B2], &h->mv[MV_FWD_X0]);

  176.             bs[5] = get_bs_p(&h->mv[MV_FWD_B3], &h->mv[MV_FWD_X1]);

  177.             break;

  178.         case B_SKIP:

  179.         case B_DIRECT:

  180.         case B_8X8:

  181.             bs[2] = get_bs_b(&h->mv[MV_FWD_X0], &h->mv[MV_FWD_X1]);

  182.             bs[3] = get_bs_b(&h->mv[MV_FWD_X2], &h->mv[MV_FWD_X3]);

  183.             bs[6] = get_bs_b(&h->mv[MV_FWD_X0], &h->mv[MV_FWD_X2]);

  184.             bs[7] = get_bs_b(&h->mv[MV_FWD_X1], &h->mv[MV_FWD_X3]);

  185.         case B_FWD_16X16:

  186.         case B_BWD_16X16:

  187.         case B_SYM_16X16:

  188.             bs[0] = get_bs_b(&h->mv[MV_FWD_A1], &h->mv[MV_FWD_X0]);

  189.             bs[1] = get_bs_b(&h->mv[MV_FWD_A3], &h->mv[MV_FWD_X2]);

  190.             bs[4] = get_bs_b(&h->mv[MV_FWD_B2], &h->mv[MV_FWD_X0]);

  191.             bs[5] = get_bs_b(&h->mv[MV_FWD_B3], &h->mv[MV_FWD_X1]);

  192.             break;

  193.         default:

  194.             if(mb_type & 1) { //16X8

  195.                 bs[6] = bs[7] = get_bs_b(&h->mv[MV_FWD_X0], &h->mv[MV_FWD_X2]);

  196.             } else {          //8X16

  197.                 bs[2] = bs[3] = get_bs_b(&h->mv[MV_FWD_X0], &h->mv[MV_FWD_X1]);

  198.             }

  199.             bs[0] = get_bs_b(&h->mv[MV_FWD_A1], &h->mv[MV_FWD_X0]);

  200.             bs[1] = get_bs_b(&h->mv[MV_FWD_A3], &h->mv[MV_FWD_X2]);

  201.             bs[4] = get_bs_b(&h->mv[MV_FWD_B2], &h->mv[MV_FWD_X0]);

  202.             bs[5] = get_bs_b(&h->mv[MV_FWD_B3], &h->mv[MV_FWD_X1]);

  203.         }

  204.         if( *((uint64_t *)bs) ) {

  205.             if(h->flags & A_AVAIL) {

  206.                 qp_avg = (h->qp + h->left_qp + 1) >> 1;

  207.                 SET_PARAMS;

  208.                 h->s.dsp.cavs_filter_lv(h->cy,h->l_stride,alpha,beta,tc,bs[0],bs[1]);

  209.                 h->s.dsp.cavs_filter_cv(h->cu,h->c_stride,alpha,beta,tc,bs[0],bs[1]);

  210.                 h->s.dsp.cavs_filter_cv(h->cv,h->c_stride,alpha,beta,tc,bs[0],bs[1]);

  211.             }

  212.             qp_avg = h->qp;

  213.             SET_PARAMS;

  214.             h->s.dsp.cavs_filter_lv(h->cy + 8,h->l_stride,alpha,beta,tc,bs[2],bs[3]);

  215.             h->s.dsp.cavs_filter_lh(h->cy + 8*h->l_stride,h->l_stride,alpha,beta,tc,

  216.                            bs[6],bs[7]);

  217. 

  218.             if(h->flags & B_AVAIL) {

  219.                 qp_avg = (h->qp + h->top_qp[h->mbx] + 1) >> 1;

  220.                 SET_PARAMS;

  221.                 h->s.dsp.cavs_filter_lh(h->cy,h->l_stride,alpha,beta,tc,bs[4],bs[5]);

  222.                 h->s.dsp.cavs_filter_ch(h->cu,h->c_stride,alpha,beta,tc,bs[4],bs[5]);

  223.                 h->s.dsp.cavs_filter_ch(h->cv,h->c_stride,alpha,beta,tc,bs[4],bs[5]);

  224.             }

  225.         }

  226.     }

  227.     h->left_qp = h->qp;

  228.     h->top_qp[h->mbx] = h->qp;

  229. }

  230. 

  231. #undef SET_PARAMS

  232. 

  233. /*****************************************************************************

  234.  *

  235.  * spatial intra prediction

  236.  *

  237.  ****************************************************************************/

  238. 

  239. static inline void load_intra_pred_luma(AVSContext *h, uint8_t *top,

  240.                                         uint8_t *left, int block) {

  241.     int i;

  242. 

  243.     switch(block) {

  244.     case 0:

  245.         memcpy(&left[1],h->left_border_y,16);

  246.         left[0] = left[1];

  247.         left[17] = left[16];

  248.         memcpy(&top[1],&h->top_border_y[h->mbx*16],16);

  249.         top[17] = top[16];

  250.         top[0] = top[1];

  251.         if((h->flags & A_AVAIL) && (h->flags & B_AVAIL))

  252.             left[0] = top[0] = h->topleft_border_y;

  253.         break;

  254.     case 1:

  255.         for(i=0;i<8;i++)

  256.             left[i+1] = *(h->cy + 7 + i*h->l_stride);

  257.         memset(&left[9],left[8],9);

  258.         left[0] = left[1];

  259.         memcpy(&top[1],&h->top_border_y[h->mbx*16+8],8);

  260.         if(h->flags & C_AVAIL)

  261.             memcpy(&top[9],&h->top_border_y[(h->mbx + 1)*16],8);

  262.         else

  263.             memset(&top[9],top[8],9);

  264.         top[17] = top[16];

  265.         top[0] = top[1];

  266.         if(h->flags & B_AVAIL)

  267.             left[0] = top[0] = h->top_border_y[h->mbx*16+7];

  268.         break;

  269.     case 2:

  270.         memcpy(&left[1],&h->left_border_y[8],8);

  271.         memset(&left[9],left[8],9);

  272.         memcpy(&top[1],h->cy + 7*h->l_stride,16);

  273.         top[17] = top[16];

  274.         left[0] = h->left_border_y[7];

  275.         top[0] = top[1];

  276.         if(h->flags & A_AVAIL)

  277.             top[0] = left[0];

  278.         break;

  279.     case 3:

  280.         for(i=0;i<9;i++)

  281.             left[i] = *(h->cy + 7 + (i+7)*h->l_stride);

  282.         memset(&left[9],left[8],9);

  283.         memcpy(&top[0],h->cy + 7 + 7*h->l_stride,9);

  284.         memset(&top[9],top[8],9);

  285.         break;

  286.     }

  287. }

  288. 

  289. static inline void load_intra_pred_chroma(uint8_t *stop, uint8_t *sleft,

  290.                                           uint8_t stopleft, uint8_t *dtop,

  291.                                           uint8_t *dleft, int stride, int flags) {

  292.     int i;

  293. 

  294.     if(flags & A_AVAIL) {

  295.         for(i=0; i<8; i++)

  296.             dleft[i+1] = sleft[i];

  297.         dleft[0] = dleft[1];

  298.         dleft[9] = dleft[8];

  299.     }

  300.     if(flags & B_AVAIL) {

  301.         for(i=0; i<8; i++)

  302.             dtop[i+1] = stop[i];

  303.         dtop[0] = dtop[1];

  304.         dtop[9] = dtop[8];

  305.         if(flags & A_AVAIL)

  306.             dleft[0] = dtop[0] = stopleft;

  307.     }

  308. }

  309. 

  310. static void intra_pred_vert(uint8_t *d,uint8_t *top,uint8_t *left,int stride) {

  311.     int y;

  312.     uint64_t a = *((uint64_t *)(&top[1]));

  313.     for(y=0;y<8;y++) {

  314.         *((uint64_t *)(d+y*stride)) = a;

  315.     }

  316. }

  317. 

  318. static void intra_pred_horiz(uint8_t *d,uint8_t *top,uint8_t *left,int stride) {

  319.     int y;

  320.     uint64_t a;

  321.     for(y=0;y<8;y++) {

  322.         a = left[y+1] * 0x0101010101010101ULL;

  323.         *((uint64_t *)(d+y*stride)) = a;

  324.     }

  325. }

  326. 

  327. static void intra_pred_dc_128(uint8_t *d,uint8_t *top,uint8_t *left,int stride) {

  328.     int y;

  329.     uint64_t a = 0x8080808080808080ULL;

  330.     for(y=0;y<8;y++)

  331.         *((uint64_t *)(d+y*stride)) = a;

  332. }

  333. 

  334. static void intra_pred_plane(uint8_t *d,uint8_t *top,uint8_t *left,int stride) {

  335.     int x,y,ia;

  336.     int ih = 0;

  337.     int iv = 0;

  338.     uint8_t *cm = cropTbl + MAX_NEG_CROP;

  339. 

  340.     for(x=0; x<4; x++) {

  341.         ih += (x+1)*(top[5+x]-top[3-x]);

  342.         iv += (x+1)*(left[5+x]-left[3-x]);

  343.     }

  344.     ia = (top[8]+left[8])<<4;

  345.     ih = (17*ih+16)>>5;

  346.     iv = (17*iv+16)>>5;

  347.     for(y=0; y<8; y++)

  348.         for(x=0; x<8; x++)

  349.             d[y*stride+x] = cm[(ia+(x-3)*ih+(y-3)*iv+16)>>5];

  350. }

  351. 

  352. #define LOWPASS(ARRAY,INDEX)                                            \

  353.     (( ARRAY[(INDEX)-1] + 2*ARRAY[(INDEX)] + ARRAY[(INDEX)+1] + 2) >> 2)

  354. 

  355. static void intra_pred_lp(uint8_t *d,uint8_t *top,uint8_t *left,int stride) {

  356.     int x,y;

  357.     for(y=0; y<8; y++)

  358.         for(x=0; x<8; x++)

  359.             d[y*stride+x] = (LOWPASS(top,x+1) + LOWPASS(left,y+1)) >> 1;

  360. }

  361. 

  362. static void intra_pred_down_left(uint8_t *d,uint8_t *top,uint8_t *left,int stride) {

  363.     int x,y;

  364.     for(y=0; y<8; y++)

  365.         for(x=0; x<8; x++)

  366.             d[y*stride+x] = (LOWPASS(top,x+y+2) + LOWPASS(left,x+y+2)) >> 1;

  367. }

  368. 

  369. static void intra_pred_down_right(uint8_t *d,uint8_t *top,uint8_t *left,int stride) {

  370.     int x,y;

  371.     for(y=0; y<8; y++)

  372.         for(x=0; x<8; x++)

  373.             if(x==y)

  374.                 d[y*stride+x] = (left[1]+2*top[0]+top[1]+2)>>2;

  375.             else if(x>y)

  376.                 d[y*stride+x] = LOWPASS(top,x-y);

  377.             else

  378.                 d[y*stride+x] = LOWPASS(left,y-x);

  379. }

  380. 

  381. static void intra_pred_lp_left(uint8_t *d,uint8_t *top,uint8_t *left,int stride) {

  382.     int x,y;

  383.     for(y=0; y<8; y++)

  384.         for(x=0; x<8; x++)

  385.             d[y*stride+x] = LOWPASS(left,y+1);

  386. }

  387. 

  388. static void intra_pred_lp_top(uint8_t *d,uint8_t *top,uint8_t *left,int stride) {

  389.     int x,y;

  390.     for(y=0; y<8; y++)

  391.         for(x=0; x<8; x++)

  392.             d[y*stride+x] = LOWPASS(top,x+1);

  393. }

  394. 

  395. #undef LOWPASS

  396. 

  397. static inline void modify_pred(const int8_t *mod_table, int *mode) {

  398.     int newmode = mod_table[*mode];

  399.     if(newmode < 0) {

  400.         av_log(NULL, AV_LOG_ERROR, "Illegal intra prediction mode\n");

  401.         *mode = 0;

  402.     } else {

  403.         *mode = newmode;

  404.     }

  405. }

  406. 

  407. /*****************************************************************************

  408.  *

  409.  * motion compensation

  410.  *

  411.  ****************************************************************************/

  412. 

  413. static inline void mc_dir_part(AVSContext *h,Picture *pic,int square,

  414.                         int chroma_height,int delta,int list,uint8_t *dest_y,

  415.                         uint8_t *dest_cb,uint8_t *dest_cr,int src_x_offset,

  416.                         int src_y_offset,qpel_mc_func *qpix_op,

  417.                         h264_chroma_mc_func chroma_op,vector_t *mv){

  418.     MpegEncContext * const s = &h->s;

  419.     const int mx= mv->x + src_x_offset*8;

  420.     const int my= mv->y + src_y_offset*8;

  421.     const int luma_xy= (mx&3) + ((my&3)<<2);

  422.     uint8_t * src_y = pic->data[0] + (mx>>2) + (my>>2)*h->l_stride;

  423.     uint8_t * src_cb= pic->data[1] + (mx>>3) + (my>>3)*h->c_stride;

  424.     uint8_t * src_cr= pic->data[2] + (mx>>3) + (my>>3)*h->c_stride;

  425.     int extra_width= 0; //(s->flags&CODEC_FLAG_EMU_EDGE) ? 0 : 16;

  426.     int extra_height= extra_width;

  427.     int emu=0;

  428.     const int full_mx= mx>>2;

  429.     const int full_my= my>>2;

  430.     const int pic_width  = 16*h->mb_width;

  431.     const int pic_height = 16*h->mb_height;

  432. 

  433.     if(!pic->data[0])

  434.         return;

  435.     if(mx&7) extra_width -= 3;

  436.     if(my&7) extra_height -= 3;

  437. 

  438.     if(   full_mx < 0-extra_width

  439.           || full_my < 0-extra_height

  440.           || full_mx + 16/*FIXME*/ > pic_width + extra_width

  441.           || full_my + 16/*FIXME*/ > pic_height + extra_height){

  442.         ff_emulated_edge_mc(s->edge_emu_buffer, src_y - 2 - 2*h->l_stride, h->l_stride,

  443.                             16+5, 16+5/*FIXME*/, full_mx-2, full_my-2, pic_width, pic_height);

  444.         src_y= s->edge_emu_buffer + 2 + 2*h->l_stride;

  445.         emu=1;

  446.     }

  447. 

  448.     qpix_op[luma_xy](dest_y, src_y, h->l_stride); //FIXME try variable height perhaps?

  449.     if(!square){

  450.         qpix_op[luma_xy](dest_y + delta, src_y + delta, h->l_stride);

  451.     }

  452. 

  453.     if(emu){

  454.         ff_emulated_edge_mc(s->edge_emu_buffer, src_cb, h->c_stride,

  455.                             9, 9/*FIXME*/, (mx>>3), (my>>3), pic_width>>1, pic_height>>1);

  456.         src_cb= s->edge_emu_buffer;

  457.     }

  458.     chroma_op(dest_cb, src_cb, h->c_stride, chroma_height, mx&7, my&7);

  459. 

  460.     if(emu){

  461.         ff_emulated_edge_mc(s->edge_emu_buffer, src_cr, h->c_stride,

  462.                             9, 9/*FIXME*/, (mx>>3), (my>>3), pic_width>>1, pic_height>>1);

  463.         src_cr= s->edge_emu_buffer;

  464.     }

  465.     chroma_op(dest_cr, src_cr, h->c_stride, chroma_height, mx&7, my&7);

  466. }

  467. 

  468. static inline void mc_part_std(AVSContext *h,int square,int chroma_height,int delta,

  469.                         uint8_t *dest_y,uint8_t *dest_cb,uint8_t *dest_cr,

  470.                         int x_offset, int y_offset,qpel_mc_func *qpix_put,

  471.                         h264_chroma_mc_func chroma_put,qpel_mc_func *qpix_avg,

  472.                         h264_chroma_mc_func chroma_avg, vector_t *mv){

  473.     qpel_mc_func *qpix_op=  qpix_put;

  474.     h264_chroma_mc_func chroma_op= chroma_put;

  475. 

  476.     dest_y  += 2*x_offset + 2*y_offset*h->l_stride;

  477.     dest_cb +=   x_offset +   y_offset*h->c_stride;

  478.     dest_cr +=   x_offset +   y_offset*h->c_stride;

  479.     x_offset += 8*h->mbx;

  480.     y_offset += 8*h->mby;

  481. 

  482.     if(mv->ref >= 0){

  483.         Picture *ref= &h->DPB[mv->ref];

  484.         mc_dir_part(h, ref, square, chroma_height, delta, 0,

  485.                     dest_y, dest_cb, dest_cr, x_offset, y_offset,

  486.                     qpix_op, chroma_op, mv);

  487. 

  488.         qpix_op=  qpix_avg;

  489.         chroma_op= chroma_avg;

  490.     }

  491. 

  492.     if((mv+MV_BWD_OFFS)->ref >= 0){

  493.         Picture *ref= &h->DPB[0];

  494.         mc_dir_part(h, ref, square, chroma_height, delta, 1,

  495.                     dest_y, dest_cb, dest_cr, x_offset, y_offset,

  496.                     qpix_op, chroma_op, mv+MV_BWD_OFFS);

  497.     }

  498. }

  499. 

  500. static void inter_pred(AVSContext *h) {

  501.     /* always do 8x8 blocks TODO: are larger blocks worth it? */

  502.     mc_part_std(h, 1, 4, 0, h->cy, h->cu, h->cv, 0, 0,

  503.                 h->s.dsp.put_cavs_qpel_pixels_tab[1],

  504.                 h->s.dsp.put_h264_chroma_pixels_tab[1],

  505.                 h->s.dsp.avg_cavs_qpel_pixels_tab[1],

  506.                 h->s.dsp.avg_h264_chroma_pixels_tab[1],&h->mv[MV_FWD_X0]);

  507.     mc_part_std(h, 1, 4, 0, h->cy, h->cu, h->cv, 4, 0,

  508.                 h->s.dsp.put_cavs_qpel_pixels_tab[1],

  509.                 h->s.dsp.put_h264_chroma_pixels_tab[1],

  510.                 h->s.dsp.avg_cavs_qpel_pixels_tab[1],

  511.                 h->s.dsp.avg_h264_chroma_pixels_tab[1],&h->mv[MV_FWD_X1]);

  512.     mc_part_std(h, 1, 4, 0, h->cy, h->cu, h->cv, 0, 4,

  513.                 h->s.dsp.put_cavs_qpel_pixels_tab[1],

  514.                 h->s.dsp.put_h264_chroma_pixels_tab[1],

  515.                 h->s.dsp.avg_cavs_qpel_pixels_tab[1],

  516.                 h->s.dsp.avg_h264_chroma_pixels_tab[1],&h->mv[MV_FWD_X2]);

  517.     mc_part_std(h, 1, 4, 0, h->cy, h->cu, h->cv, 4, 4,

  518.                 h->s.dsp.put_cavs_qpel_pixels_tab[1],

  519.                 h->s.dsp.put_h264_chroma_pixels_tab[1],

  520.                 h->s.dsp.avg_cavs_qpel_pixels_tab[1],

  521.                 h->s.dsp.avg_h264_chroma_pixels_tab[1],&h->mv[MV_FWD_X3]);

  522.     /* set intra prediction modes to default values */

  523.     h->pred_mode_Y[3] =  h->pred_mode_Y[6] = INTRA_L_LP;

  524.     h->top_pred_Y[h->mbx*2+0] = h->top_pred_Y[h->mbx*2+1] = INTRA_L_LP;

  525. }

  526. 

  527. /*****************************************************************************

  528.  *

  529.  * motion vector prediction

  530.  *

  531.  ****************************************************************************/

  532. 

  533. static inline void set_mvs(vector_t *mv, enum block_t size) {

  534.     switch(size) {

  535.     case BLK_16X16:

  536.         mv[MV_STRIDE  ] = mv[0];

  537.         mv[MV_STRIDE+1] = mv[0];

  538.     case BLK_16X8:

  539.         mv[1] = mv[0];

  540.         break;

  541.     case BLK_8X16:

  542.         mv[MV_STRIDE] = mv[0];

  543.         break;

  544.     }

  545. }

  546. 

  547. static inline void store_mvs(AVSContext *h) {

  548.     h->col_mv[(h->mby*h->mb_width + h->mbx)*4 + 0] = h->mv[MV_FWD_X0];

  549.     h->col_mv[(h->mby*h->mb_width + h->mbx)*4 + 1] = h->mv[MV_FWD_X1];

  550.     h->col_mv[(h->mby*h->mb_width + h->mbx)*4 + 2] = h->mv[MV_FWD_X2];

  551.     h->col_mv[(h->mby*h->mb_width + h->mbx)*4 + 3] = h->mv[MV_FWD_X3];

  552. }

  553. 

  554. static inline void scale_mv(AVSContext *h, int *d_x, int *d_y, vector_t *src, int distp) {

  555.     int den = h->scale_den[src->ref];

  556. 

  557.     *d_x = (src->x*distp*den + 256 + (src->x>>31)) >> 9;

  558.     *d_y = (src->y*distp*den + 256 + (src->y>>31)) >> 9;

  559. }

  560. 

  561. static inline void mv_pred_median(AVSContext *h, vector_t *mvP, vector_t *mvA, vector_t *mvB, vector_t *mvC) {

  562.     int ax, ay, bx, by, cx, cy;

  563.     int len_ab, len_bc, len_ca, len_mid;

  564. 

  565.     /* scale candidates according to their temporal span */

  566.     scale_mv(h, &ax, &ay, mvA, mvP->dist);

  567.     scale_mv(h, &bx, &by, mvB, mvP->dist);

  568.     scale_mv(h, &cx, &cy, mvC, mvP->dist);

  569.     /* find the geometrical median of the three candidates */

  570.     len_ab = abs(ax - bx) + abs(ay - by);

  571.     len_bc = abs(bx - cx) + abs(by - cy);

  572.     len_ca = abs(cx - ax) + abs(cy - ay);

  573.     len_mid = mid_pred(len_ab, len_bc, len_ca);

  574.     if(len_mid == len_ab) {

  575.         mvP->x = cx;

  576.         mvP->y = cy;

  577.     } else if(len_mid == len_bc) {

  578.         mvP->x = ax;

  579.         mvP->y = ay;

  580.     } else {

  581.         mvP->x = bx;

  582.         mvP->y = by;

  583.     }

  584. }

  585. 

  586. static inline void mv_pred_direct(AVSContext *h, vector_t *pmv_fw,

  587.                                   vector_t *pmv_bw, vector_t *col_mv) {

  588.     int den = h->direct_den[col_mv->ref];

  589.     int m = col_mv->x >> 31;

  590. 

  591.     pmv_fw->dist = h->dist[1];

  592.     pmv_bw->dist = h->dist[0];

  593.     pmv_fw->ref = 1;

  594.     pmv_bw->ref = 0;

  595.     /* scale the co-located motion vector according to its temporal span */

  596.     pmv_fw->x = (((den+(den*col_mv->x*pmv_fw->dist^m)-m-1)>>14)^m)-m;

  597.     pmv_bw->x = m-(((den+(den*col_mv->x*pmv_bw->dist^m)-m-1)>>14)^m);

  598.     m = col_mv->y >> 31;

  599.     pmv_fw->y = (((den+(den*col_mv->y*pmv_fw->dist^m)-m-1)>>14)^m)-m;

  600.     pmv_bw->y = m-(((den+(den*col_mv->y*pmv_bw->dist^m)-m-1)>>14)^m);

  601. }

  602. 

  603. static inline void mv_pred_sym(AVSContext *h, vector_t *src, enum block_t size) {

  604.     vector_t *dst = src + MV_BWD_OFFS;

  605. 

  606.     /* backward mv is the scaled and negated forward mv */

  607.     dst->x = -((src->x * h->sym_factor + 256) >> 9);

  608.     dst->y = -((src->y * h->sym_factor + 256) >> 9);

  609.     dst->ref = 0;

  610.     dst->dist = h->dist[0];

  611.     set_mvs(dst, size);

  612. }

  613. 

  614. static void mv_pred(AVSContext *h, enum mv_loc_t nP, enum mv_loc_t nC,

  615.                     enum mv_pred_t mode, enum block_t size, int ref) {

  616.     vector_t *mvP = &h->mv[nP];

  617.     vector_t *mvA = &h->mv[nP-1];

  618.     vector_t *mvB = &h->mv[nP-4];

  619.     vector_t *mvC = &h->mv[nC];

  620.     int mvAref = mvA->ref;

  621.     int mvBref = mvB->ref;

  622.     int mvCref;

  623. 

  624.     mvP->ref = ref;

  625.     mvP->dist = h->dist[mvP->ref];

  626.     if(mvC->ref == NOT_AVAIL)

  627.         mvC = &h->mv[nP-5]; // set to top-left (mvD)

  628.     mvCref = mvC->ref;

  629.     if(mode == MV_PRED_PSKIP) {

  630.         if((mvAref == NOT_AVAIL) || (mvBref == NOT_AVAIL) ||

  631.            ((mvA->x | mvA->y | mvA->ref) == 0)  ||

  632.            ((mvB->x | mvB->y | mvB->ref) == 0) ) {

  633.             mvP->x = mvP->y = 0;

  634.             set_mvs(mvP,size);

  635.             return;

  636.         }

  637.     }

  638.     /* if there is only one suitable candidate, take it */

  639.     if((mvAref >= 0) && (mvBref < 0) && (mvCref < 0)) {

  640.         mvP->x = mvA->x;

  641.         mvP->y = mvA->y;

  642.     } else if((mvAref < 0) && (mvBref >= 0) && (mvCref < 0)) {

  643.         mvP->x = mvB->x;

  644.         mvP->y = mvB->y;

  645.     } else if((mvAref < 0) && (mvBref < 0) && (mvCref >= 0)) {

  646.         mvP->x = mvC->x;

  647.         mvP->y = mvC->y;

  648.     } else {

  649.         switch(mode) {

  650.         case MV_PRED_LEFT:

  651.             if(mvAref == mvP->ref) {

  652.                 mvP->x = mvA->x;

  653.                 mvP->y = mvA->y;

  654.             } else

  655.                 mv_pred_median(h, mvP, mvA, mvB, mvC);

  656.             break;

  657.         case MV_PRED_TOP:

  658.             if(mvBref == mvP->ref) {

  659.                 mvP->x = mvB->x;

  660.                 mvP->y = mvB->y;

  661.             } else

  662.                 mv_pred_median(h, mvP, mvA, mvB, mvC);

  663.             break;

  664.         case MV_PRED_TOPRIGHT:

  665.             if(mvCref == mvP->ref) {

  666.                 mvP->x = mvC->x;

  667.                 mvP->y = mvC->y;

  668.             } else

  669.                 mv_pred_median(h, mvP, mvA, mvB, mvC);

  670.             break;

  671.         default:

  672.             mv_pred_median(h, mvP, mvA, mvB, mvC);

  673.             break;

  674.         }

  675.     }

  676.     if(mode < MV_PRED_PSKIP) {

  677.         mvP->x += get_se_golomb(&h->s.gb);

  678.         mvP->y += get_se_golomb(&h->s.gb);

  679.     }

  680.     set_mvs(mvP,size);

  681. }

  682. 

  683. /*****************************************************************************

  684.  *

  685.  * residual data decoding

  686.  *

  687.  ****************************************************************************/

  688. 

  689. /* kth-order exponential golomb code */

  690. static inline int get_ue_code(GetBitContext *gb, int order) {

  691.     if(order)

  692.         return (get_ue_golomb(gb) << order) + get_bits(gb,order);

  693.     return get_ue_golomb(gb);

  694. }

  695. 

  696. static int decode_residual_block(AVSContext *h, GetBitContext *gb,

  697.                                  const residual_vlc_t *r, int esc_golomb_order,

  698.                                  int qp, uint8_t *dst, int stride) {

  699.     int i,pos = -1;

  700.     int level_code, esc_code, level, run, mask;

  701.     int level_buf[64];

  702.     int run_buf[64];

  703.     int dqm = dequant_mul[qp];

  704.     int dqs = dequant_shift[qp];

  705.     int dqa = 1 << (dqs - 1);

  706.     const uint8_t *scantab = ff_zigzag_direct;

  707.     DCTELEM block[64];

  708. 

  709.     memset(block,0,64*sizeof(DCTELEM));

  710.     for(i=0;i<65;i++) {

  711.         level_code = get_ue_code(gb,r->golomb_order);

  712.         if(level_code >= ESCAPE_CODE) {

  713.             run = (level_code - ESCAPE_CODE) >> 1;

  714.             esc_code = get_ue_code(gb,esc_golomb_order);

  715.             level = esc_code + (run > r->max_run ? 1 : r->level_add[run]);

  716.             while(level > r->inc_limit)

  717.                 r++;

  718.             mask = -(level_code & 1);

  719.             level = (level^mask) - mask;

  720.         } else {

  721.             if(level_code < 0)

  722.                 return -1;

  723.             level = r->rltab[level_code][0];

  724.             if(!level) //end of block signal

  725.                 break;

  726.             run   = r->rltab[level_code][1];

  727.             r += r->rltab[level_code][2];

  728.         }

  729.         level_buf[i] = level;

  730.         run_buf[i] = run;

  731.     }

  732.     /* inverse scan and dequantization */

  733.     for(i=i-1;i>=0;i--) {

  734.         pos += 1 + run_buf[i];

  735.         if(pos > 63) {

  736.             av_log(h->s.avctx, AV_LOG_ERROR,

  737.                    "position out of block bounds at pic %d MB(%d,%d)\n",

  738.                    h->picture.poc, h->mbx, h->mby);

  739.             return -1;

  740.         }

  741.         block[scantab[pos]] = (level_buf[i]*dqm + dqa) >> dqs;

  742.     }

  743.     h->s.dsp.cavs_idct8_add(dst,block,stride);

  744.     return 0;

  745. }

  746. 

  747. 

  748. static inline void decode_residual_chroma(AVSContext *h) {

  749.     if(h->cbp & (1<<4))

  750.         decode_residual_block(h,&h->s.gb,chroma_2dvlc,0, chroma_qp[h->qp],

  751.                               h->cu,h->c_stride);

  752.     if(h->cbp & (1<<5))

  753.         decode_residual_block(h,&h->s.gb,chroma_2dvlc,0, chroma_qp[h->qp],

  754.                               h->cv,h->c_stride);

  755. }

  756. 

  757. static inline void decode_residual_inter(AVSContext *h) {

  758.     int block;

  759. 

  760.     /* get coded block pattern */

  761.     h->cbp = cbp_tab[get_ue_golomb(&h->s.gb)][1];

  762.     /* get quantizer */

  763.     if(h->cbp && !h->qp_fixed)

  764.         h->qp += get_se_golomb(&h->s.gb);

  765.     for(block=0;block<4;block++)

  766.         if(h->cbp & (1<<block))

  767.             decode_residual_block(h,&h->s.gb,inter_2dvlc,0,h->qp,

  768.                                   h->cy + h->luma_scan[block], h->l_stride);

  769.     decode_residual_chroma(h);

  770. }

  771. 

  772. /*****************************************************************************

  773.  *

  774.  * macroblock level

  775.  *

  776.  ****************************************************************************/

  777. 

  778. static inline void init_mb(AVSContext *h) {

  779.     int i;

  780. 

  781.     /* copy predictors from top line (MB B and C) into cache */

  782.     for(i=0;i<3;i++) {

  783.         h->mv[MV_FWD_B2+i] = h->top_mv[0][h->mbx*2+i];

  784.         h->mv[MV_BWD_B2+i] = h->top_mv[1][h->mbx*2+i];

  785.     }

  786.     h->pred_mode_Y[1] = h->top_pred_Y[h->mbx*2+0];

  787.     h->pred_mode_Y[2] = h->top_pred_Y[h->mbx*2+1];

  788.     /* clear top predictors if MB B is not available */

  789.     if(!(h->flags & B_AVAIL)) {

  790.         h->mv[MV_FWD_B2] = un_mv;

  791.         h->mv[MV_FWD_B3] = un_mv;

  792.         h->mv[MV_BWD_B2] = un_mv;

  793.         h->mv[MV_BWD_B3] = un_mv;

  794.         h->pred_mode_Y[1] = h->pred_mode_Y[2] = NOT_AVAIL;

  795.         h->flags &= ~(C_AVAIL|D_AVAIL);

  796.     } else if(h->mbx) {

  797.         h->flags |= D_AVAIL;

  798.     }

  799.     if(h->mbx == h->mb_width-1) //MB C not available

  800.         h->flags &= ~C_AVAIL;

  801.     /* clear top-right predictors if MB C is not available */

  802.     if(!(h->flags & C_AVAIL)) {

  803.         h->mv[MV_FWD_C2] = un_mv;

  804.         h->mv[MV_BWD_C2] = un_mv;

  805.     }

  806.     /* clear top-left predictors if MB D is not available */

  807.     if(!(h->flags & D_AVAIL)) {

  808.         h->mv[MV_FWD_D3] = un_mv;

  809.         h->mv[MV_BWD_D3] = un_mv;

  810.     }

  811.     /* set pointer for co-located macroblock type */

  812.     h->col_type = &h->col_type_base[h->mby*h->mb_width + h->mbx];

  813. }

  814. 

  815. static inline void check_for_slice(AVSContext *h);

  816. 

  817. static inline int next_mb(AVSContext *h) {

  818.     int i;

  819. 

  820.     h->flags |= A_AVAIL;

  821.     h->cy += 16;

  822.     h->cu += 8;

  823.     h->cv += 8;

  824.     /* copy mvs as predictors to the left */

  825.     for(i=0;i<=20;i+=4)

  826.         h->mv[i] = h->mv[i+2];

  827.     /* copy bottom mvs from cache to top line */

  828.     h->top_mv[0][h->mbx*2+0] = h->mv[MV_FWD_X2];

  829.     h->top_mv[0][h->mbx*2+1] = h->mv[MV_FWD_X3];

  830.     h->top_mv[1][h->mbx*2+0] = h->mv[MV_BWD_X2];

  831.     h->top_mv[1][h->mbx*2+1] = h->mv[MV_BWD_X3];

  832.     /* next MB address */

  833.     h->mbx++;

  834.     if(h->mbx == h->mb_width) { //new mb line

  835.         h->flags = B_AVAIL|C_AVAIL;

  836.         /* clear left pred_modes */

  837.         h->pred_mode_Y[3] = h->pred_mode_Y[6] = NOT_AVAIL;

  838.         /* clear left mv predictors */

  839.         for(i=0;i<=20;i+=4)

  840.             h->mv[i] = un_mv;

  841.         h->mbx = 0;

  842.         h->mby++;

  843.         /* re-calculate sample pointers */

  844.         h->cy = h->picture.data[0] + h->mby*16*h->l_stride;

  845.         h->cu = h->picture.data[1] + h->mby*8*h->c_stride;

  846.         h->cv = h->picture.data[2] + h->mby*8*h->c_stride;

  847.         if(h->mby == h->mb_height) { //frame end

  848.             return 0;

  849.         } else {

  850.             //check_for_slice(h);

  851.         }

  852.     }

  853.     return 1;

  854. }

  855. 

  856. static void decode_mb_i(AVSContext *h, int is_i_pic) {

  857.     GetBitContext *gb = &h->s.gb;

  858.     int block, pred_mode_uv;

  859.     uint8_t top[18];

  860.     uint8_t left[18];

  861.     uint8_t *d;

  862. 

  863.     /* get intra prediction modes from stream */

  864.     for(block=0;block<4;block++) {

  865.         int nA,nB,predpred;

  866.         int pos = scan3x3[block];

  867. 

  868.         nA = h->pred_mode_Y[pos-1];

  869.         nB = h->pred_mode_Y[pos-3];

  870.         if((nA == NOT_AVAIL) || (nB == NOT_AVAIL))

  871.             predpred = 2;

  872.         else

  873.             predpred = FFMIN(nA,nB);

  874.         if(get_bits1(gb))

  875.             h->pred_mode_Y[pos] = predpred;

  876.         else {

  877.             h->pred_mode_Y[pos] = get_bits(gb,2);

  878.             if(h->pred_mode_Y[pos] >= predpred)

  879.                 h->pred_mode_Y[pos]++;

  880.         }

  881.     }

  882.     pred_mode_uv = get_ue_golomb(gb);

  883.     if(pred_mode_uv > 6) {

  884.         av_log(h->s.avctx, AV_LOG_ERROR, "illegal intra chroma pred mode\n");

  885.         pred_mode_uv = 0;

  886.     }

  887. 

  888.     /* save pred modes before they get modified */

  889.     h->pred_mode_Y[3] =  h->pred_mode_Y[5];

  890.     h->pred_mode_Y[6] =  h->pred_mode_Y[8];

  891.     h->top_pred_Y[h->mbx*2+0] = h->pred_mode_Y[7];

  892.     h->top_pred_Y[h->mbx*2+1] = h->pred_mode_Y[8];

  893. 

  894.     /* modify pred modes according to availability of neighbour samples */

  895.     if(!(h->flags & A_AVAIL)) {

  896.         modify_pred(left_modifier_l, &h->pred_mode_Y[4] );

  897.         modify_pred(left_modifier_l, &h->pred_mode_Y[7] );

  898.         modify_pred(left_modifier_c, &pred_mode_uv );

  899.     }

  900.     if(!(h->flags & B_AVAIL)) {

  901.         modify_pred(top_modifier_l, &h->pred_mode_Y[4] );

  902.         modify_pred(top_modifier_l, &h->pred_mode_Y[5] );

  903.         modify_pred(top_modifier_c, &pred_mode_uv );

  904.     }

  905. 

  906.     /* get coded block pattern */

  907.     if(is_i_pic)

  908.         h->cbp = cbp_tab[get_ue_golomb(gb)][0];

  909.     if(h->cbp && !h->qp_fixed)

  910.         h->qp += get_se_golomb(gb); //qp_delta

  911. 

  912.     /* luma intra prediction interleaved with residual decode/transform/add */

  913.     for(block=0;block<4;block++) {

  914.         d = h->cy + h->luma_scan[block];

  915.         load_intra_pred_luma(h, top, left, block);

  916.         h->intra_pred_l[h->pred_mode_Y[scan3x3[block]]]

  917.             (d, top, left, h->l_stride);

  918.         if(h->cbp & (1<<block))

  919.             decode_residual_block(h,gb,intra_2dvlc,1,h->qp,d,h->l_stride);

  920.     }

  921. 

  922.     /* chroma intra prediction */

  923.     load_intra_pred_chroma(&h->top_border_u[h->mbx*8], h->left_border_u,

  924.                            h->topleft_border_u, top, left, h->c_stride, h->flags);

  925.     h->intra_pred_c[pred_mode_uv](h->cu, top, left, h->c_stride);

  926.     load_intra_pred_chroma(&h->top_border_v[h->mbx*8], h->left_border_v,

  927.                            h->topleft_border_v, top, left, h->c_stride, h->flags);

  928.     h->intra_pred_c[pred_mode_uv](h->cv, top, left, h->c_stride);

  929. 

  930.     decode_residual_chroma(h);

  931.     filter_mb(h,I_8X8);

  932. 

  933.     /* mark motion vectors as intra */

  934.     h->mv[MV_FWD_X0] = intra_mv;

  935.     set_mvs(&h->mv[MV_FWD_X0], BLK_16X16);

  936.     h->mv[MV_BWD_X0] = intra_mv;

  937.     set_mvs(&h->mv[MV_BWD_X0], BLK_16X16);

  938.     if(h->pic_type != FF_B_TYPE)

  939.         *h->col_type = I_8X8;

  940. }

  941. 

  942. static void mb_skip_p(AVSContext *h) {

  943.     mv_pred(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_PSKIP, BLK_16X16, 0);

  944.     inter_pred(h);

  945.     store_mvs(h);

  946.     filter_mb(h,P_SKIP);

  947.     *h->col_type = P_SKIP;

  948. }

  949. 

  950. 

  951. static void mb_skip_b(AVSContext *h) {

  952.     int i;

  953. 

  954.     if(!(*h->col_type)) {

  955.         /* intra MB at co-location, do in-plane prediction */

  956.         mv_pred(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_BSKIP, BLK_16X16, 1);

  957.         mv_pred(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_BSKIP, BLK_16X16, 0);

  958.     } else {

  959.         /* direct prediction from co-located P MB, block-wise */

  960.         for(i=0;i<4;i++)

  961.             mv_pred_direct(h,&h->mv[mv_scan[i]],

  962.                            &h->mv[mv_scan[i]+MV_BWD_OFFS],

  963.                            &h->col_mv[(h->mby*h->mb_width + h->mbx)*4 + i]);

  964.     }

  965. }

  966. 

  967. static void decode_mb_p(AVSContext *h, enum mb_t mb_type) {

  968.     GetBitContext *gb = &h->s.gb;

  969.     int ref[4];

  970. 

  971.     switch(mb_type) {

  972.     case P_SKIP:

  973.         mb_skip_p(h);

  974.         return;

  975.     case P_16X16:

  976.         ref[0] = h->ref_flag ? 0 : get_bits1(gb);

  977.         mv_pred(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN,   BLK_16X16,ref[0]);

  978.         break;

  979.     case P_16X8:

  980.         ref[0] = h->ref_flag ? 0 : get_bits1(gb);

  981.         ref[2] = h->ref_flag ? 0 : get_bits1(gb);

  982.         mv_pred(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_TOP,      BLK_16X8, ref[0]);

  983.         mv_pred(h, MV_FWD_X2, MV_FWD_A1, MV_PRED_LEFT,     BLK_16X8, ref[2]);

  984.         break;

  985.     case P_8X16:

  986.         ref[0] = h->ref_flag ? 0 : get_bits1(gb);

  987.         ref[1] = h->ref_flag ? 0 : get_bits1(gb);

  988.         mv_pred(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_LEFT,     BLK_8X16, ref[0]);

  989.         mv_pred(h, MV_FWD_X1, MV_FWD_C2, MV_PRED_TOPRIGHT, BLK_8X16, ref[1]);

  990.         break;

  991.     case P_8X8:

  992.         ref[0] = h->ref_flag ? 0 : get_bits1(gb);

  993.         ref[1] = h->ref_flag ? 0 : get_bits1(gb);

  994.         ref[2] = h->ref_flag ? 0 : get_bits1(gb);

  995.         ref[3] = h->ref_flag ? 0 : get_bits1(gb);

  996.         mv_pred(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_MEDIAN,   BLK_8X8, ref[0]);

  997.         mv_pred(h, MV_FWD_X1, MV_FWD_C2, MV_PRED_MEDIAN,   BLK_8X8, ref[1]);

  998.         mv_pred(h, MV_FWD_X2, MV_FWD_X1, MV_PRED_MEDIAN,   BLK_8X8, ref[2]);

  999.         mv_pred(h, MV_FWD_X3, MV_FWD_X0, MV_PRED_MEDIAN,   BLK_8X8, ref[3]);

  1000.     }

  1001.     inter_pred(h);

  1002.     store_mvs(h);

  1003.     decode_residual_inter(h);

  1004.     filter_mb(h,mb_type);

  1005.     *h->col_type = mb_type;

  1006. }

  1007. 

  1008. static void decode_mb_b(AVSContext *h, enum mb_t mb_type) {

  1009.     int block;

  1010.     enum sub_mb_t sub_type[4];

  1011.     int flags;

  1012. 

  1013.     /* reset all MVs */

  1014.     h->mv[MV_FWD_X0] = dir_mv;

  1015.     set_mvs(&h->mv[MV_FWD_X0], BLK_16X16);

  1016.     h->mv[MV_BWD_X0] = dir_mv;

  1017.     set_mvs(&h->mv[MV_BWD_X0], BLK_16X16);

  1018.     switch(mb_type) {

  1019.     case B_SKIP:

  1020.         mb_skip_b(h);

  1021.         inter_pred(h);

  1022.         filter_mb(h,B_SKIP);

  1023.         return;

  1024.     case B_DIRECT:

  1025.         mb_skip_b(h);

  1026.         break;

  1027.     case B_FWD_16X16:

  1028.         mv_pred(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16, 1);

  1029.         break;

  1030.     case B_SYM_16X16:

  1031.         mv_pred(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16, 1);

  1032.         mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_16X16);

  1033.         break;

  1034.     case B_BWD_16X16:

  1035.         mv_pred(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_MEDIAN, BLK_16X16, 0);

  1036.         break;

  1037.     case B_8X8:

  1038.         for(block=0;block<4;block++)

  1039.             sub_type[block] = get_bits(&h->s.gb,2);

  1040.         for(block=0;block<4;block++) {

  1041.             switch(sub_type[block]) {

  1042.             case B_SUB_DIRECT:

  1043.                 if(!(*h->col_type)) {

  1044.                     /* intra MB at co-location, do in-plane prediction */

  1045.                     mv_pred(h, mv_scan[block], mv_scan[block]-3,

  1046.                             MV_PRED_BSKIP, BLK_8X8, 1);

  1047.                     mv_pred(h, mv_scan[block]+MV_BWD_OFFS,

  1048.                             mv_scan[block]-3+MV_BWD_OFFS,

  1049.                             MV_PRED_BSKIP, BLK_8X8, 0);

  1050.                 } else

  1051.                     mv_pred_direct(h,&h->mv[mv_scan[block]],

  1052.                                    &h->mv[mv_scan[block]+MV_BWD_OFFS],

  1053.                                    &h->col_mv[(h->mby*h->mb_width + h->mbx)*4 + block]);

  1054.                 break;

  1055.             case B_SUB_FWD:

  1056.                 mv_pred(h, mv_scan[block], mv_scan[block]-3,

  1057.                         MV_PRED_MEDIAN, BLK_8X8, 1);

  1058.                 break;

  1059.             case B_SUB_SYM:

  1060.                 mv_pred(h, mv_scan[block], mv_scan[block]-3,

  1061.                         MV_PRED_MEDIAN, BLK_8X8, 1);

  1062.                 mv_pred_sym(h, &h->mv[mv_scan[block]], BLK_8X8);

  1063.                 break;

  1064.             }

  1065.         }

  1066.         for(block=0;block<4;block++) {

  1067.             if(sub_type[block] == B_SUB_BWD)

  1068.                 mv_pred(h, mv_scan[block]+MV_BWD_OFFS,

  1069.                         mv_scan[block]+MV_BWD_OFFS-3,

  1070.                         MV_PRED_MEDIAN, BLK_8X8, 0);

  1071.         }

  1072.         break;

  1073.     default:

  1074.         assert((mb_type > B_SYM_16X16) && (mb_type < B_8X8));

  1075.         flags = b_partition_flags[(mb_type-1)>>1];

  1076.         if(mb_type & 1) { /* 16x8 macroblock types */

  1077.             if(flags & FWD0)

  1078.                 mv_pred(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_TOP,  BLK_16X8, 1);

  1079.             if(flags & SYM0) {

  1080.                 mv_pred(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_TOP,  BLK_16X8, 1);

  1081.                 mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_16X8);

  1082.             }

  1083.             if(flags & FWD1)

  1084.                 mv_pred(h, MV_FWD_X2, MV_FWD_A1, MV_PRED_LEFT, BLK_16X8, 1);

  1085.             if(flags & SYM1) {

  1086.                 mv_pred(h, MV_FWD_X2, MV_FWD_A1, MV_PRED_LEFT, BLK_16X8, 1);

  1087.                 mv_pred_sym(h, &h->mv[9], BLK_16X8);

  1088.             }

  1089.             if(flags & BWD0)

  1090.                 mv_pred(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_TOP,  BLK_16X8, 0);

  1091.             if(flags & BWD1)

  1092.                 mv_pred(h, MV_BWD_X2, MV_BWD_A1, MV_PRED_LEFT, BLK_16X8, 0);

  1093.         } else {          /* 8x16 macroblock types */

  1094.             if(flags & FWD0)

  1095.                 mv_pred(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_LEFT, BLK_8X16, 1);

  1096.             if(flags & SYM0) {

  1097.                 mv_pred(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_LEFT, BLK_8X16, 1);

  1098.                 mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_8X16);

  1099.             }

  1100.             if(flags & FWD1)

  1101.                 mv_pred(h, MV_FWD_X1, MV_FWD_C2, MV_PRED_TOPRIGHT,BLK_8X16, 1);

  1102.             if(flags & SYM1) {

  1103.                 mv_pred(h, MV_FWD_X1, MV_FWD_C2, MV_PRED_TOPRIGHT,BLK_8X16, 1);

  1104.                 mv_pred_sym(h, &h->mv[6], BLK_8X16);

  1105.             }

  1106.             if(flags & BWD0)

  1107.                 mv_pred(h, MV_BWD_X0, MV_BWD_B3, MV_PRED_LEFT, BLK_8X16, 0);

  1108.             if(flags & BWD1)

  1109.                 mv_pred(h, MV_BWD_X1, MV_BWD_C2, MV_PRED_TOPRIGHT,BLK_8X16, 0);

  1110.         }

  1111.     }

  1112.     inter_pred(h);

  1113.     decode_residual_inter(h);

  1114.     filter_mb(h,mb_type);

  1115. }

  1116. 

  1117. /*****************************************************************************

  1118.  *

  1119.  * slice level

  1120.  *

  1121.  ****************************************************************************/

  1122. 

  1123. static inline int decode_slice_header(AVSContext *h, GetBitContext *gb) {

  1124.     if(h->stc > 0xAF)

  1125.         av_log(h->s.avctx, AV_LOG_ERROR, "unexpected start code 0x%02x\n", h->stc);

  1126.     h->mby = h->stc;

  1127.     if((h->mby == 0) && (!h->qp_fixed)){

  1128.         h->qp_fixed = get_bits1(gb);

  1129.         h->qp = get_bits(gb,6);

  1130.     }

  1131.     /* inter frame or second slice can have weighting params */

  1132.     if((h->pic_type != FF_I_TYPE) || (!h->pic_structure && h->mby >= h->mb_width/2))

  1133.         if(get_bits1(gb)) { //slice_weighting_flag

  1134.             av_log(h->s.avctx, AV_LOG_ERROR,

  1135.                    "weighted prediction not yet supported\n");

  1136.         }

  1137.     return 0;

  1138. }

  1139. 

  1140. static inline void check_for_slice(AVSContext *h) {

  1141.     GetBitContext *gb = &h->s.gb;

  1142.     int align;

  1143.     align = (-get_bits_count(gb)) & 7;

  1144.     if((show_bits_long(gb,24+align) & 0xFFFFFF) == 0x000001) {

  1145.         get_bits_long(gb,24+align);

  1146.         h->stc = get_bits(gb,8);

  1147.         decode_slice_header(h,gb);

  1148.     }

  1149. }

  1150. 

  1151. /*****************************************************************************

  1152.  *

  1153.  * frame level

  1154.  *

  1155.  ****************************************************************************/

  1156. 

  1157. static void init_pic(AVSContext *h) {

  1158.     int i;

  1159. 

  1160.     /* clear some predictors */

  1161.     for(i=0;i<=20;i+=4)

  1162.         h->mv[i] = un_mv;

  1163.     h->mv[MV_BWD_X0] = dir_mv;

  1164.     set_mvs(&h->mv[MV_BWD_X0], BLK_16X16);

  1165.     h->mv[MV_FWD_X0] = dir_mv;

  1166.     set_mvs(&h->mv[MV_FWD_X0], BLK_16X16);

  1167.     h->pred_mode_Y[3] = h->pred_mode_Y[6] = NOT_AVAIL;

  1168.     h->cy = h->picture.data[0];

  1169.     h->cu = h->picture.data[1];

  1170.     h->cv = h->picture.data[2];

  1171.     h->l_stride = h->picture.linesize[0];

  1172.     h->c_stride = h->picture.linesize[1];

  1173.     h->luma_scan[2] = 8*h->l_stride;

  1174.     h->luma_scan[3] = 8*h->l_stride+8;

  1175.     h->mbx = h->mby = 0;

  1176.     h->flags = 0;

  1177. }

  1178. 

  1179. static int decode_pic(AVSContext *h) {

  1180.     MpegEncContext *s = &h->s;

  1181.     int i,skip_count;

  1182.     enum mb_t mb_type;

  1183. 

  1184.     if (!s->context_initialized) {

  1185.         if (MPV_common_init(s) < 0)

  1186.             return -1;

  1187.     }

  1188.     get_bits(&s->gb,16);//bbv_dwlay

  1189.     if(h->stc == PIC_PB_START_CODE) {

  1190.         h->pic_type = get_bits(&s->gb,2) + FF_I_TYPE;

  1191.         /* make sure we have the reference frames we need */

  1192.         if(!h->DPB[0].data[0] ||

  1193.           (!h->DPB[1].data[0] && h->pic_type == FF_B_TYPE))

  1194.             return -1;

  1195.     } else {

  1196.         h->pic_type = FF_I_TYPE;

  1197.         if(get_bits1(&s->gb))

  1198.             get_bits(&s->gb,16);//time_code

  1199.     }

  1200.     /* release last B frame */

  1201.     if(h->picture.data[0])

  1202.         s->avctx->release_buffer(s->avctx, (AVFrame *)&h->picture);

  1203. 

  1204.     s->avctx->get_buffer(s->avctx, (AVFrame *)&h->picture);

  1205.     init_pic(h);

  1206.     h->picture.poc = get_bits(&s->gb,8)*2;

  1207. 

  1208.     /* get temporal distances and MV scaling factors */

  1209.     if(h->pic_type != FF_B_TYPE) {

  1210.         h->dist[0] = (h->picture.poc - h->DPB[0].poc  + 512) % 512;

  1211.     } else {

  1212.         h->dist[0] = (h->DPB[0].poc  - h->picture.poc + 512) % 512;

  1213.     }

  1214.     h->dist[1] = (h->picture.poc - h->DPB[1].poc  + 512) % 512;

  1215.     h->scale_den[0] = h->dist[0] ? 512/h->dist[0] : 0;

  1216.     h->scale_den[1] = h->dist[1] ? 512/h->dist[1] : 0;

  1217.     if(h->pic_type == FF_B_TYPE) {

  1218.         h->sym_factor = h->dist[0]*h->scale_den[1];

  1219.     } else {

  1220.         h->direct_den[0] = h->dist[0] ? 16384/h->dist[0] : 0;

  1221.         h->direct_den[1] = h->dist[1] ? 16384/h->dist[1] : 0;

  1222.     }

  1223. 

  1224.     if(s->low_delay)

  1225.         get_ue_golomb(&s->gb); //bbv_check_times

  1226.     h->progressive             = get_bits1(&s->gb);

  1227.     if(h->progressive)

  1228.         h->pic_structure = 1;

  1229.     else if(!(h->pic_structure = get_bits1(&s->gb) && (h->stc == PIC_PB_START_CODE)) )

  1230.         get_bits1(&s->gb);     //advanced_pred_mode_disable

  1231.     skip_bits1(&s->gb);        //top_field_first

  1232.     skip_bits1(&s->gb);        //repeat_first_field

  1233.     h->qp_fixed                = get_bits1(&s->gb);

  1234.     h->qp                      = get_bits(&s->gb,6);

  1235.     if(h->pic_type == FF_I_TYPE) {

  1236.         if(!h->progressive && !h->pic_structure)

  1237.             skip_bits1(&s->gb);//what is this?

  1238.         skip_bits(&s->gb,4);   //reserved bits

  1239.     } else {

  1240.         if(!(h->pic_type == FF_B_TYPE && h->pic_structure == 1))

  1241.             h->ref_flag        = get_bits1(&s->gb);

  1242.         skip_bits(&s->gb,4);   //reserved bits

  1243.         h->skip_mode_flag      = get_bits1(&s->gb);

  1244.     }

  1245.     h->loop_filter_disable     = get_bits1(&s->gb);

  1246.     if(!h->loop_filter_disable && get_bits1(&s->gb)) {

  1247.         h->alpha_offset        = get_se_golomb(&s->gb);

  1248.         h->beta_offset         = get_se_golomb(&s->gb);

  1249.     } else {

  1250.         h->alpha_offset = h->beta_offset  = 0;

  1251.     }

  1252.     check_for_slice(h);

  1253.     if(h->pic_type == FF_I_TYPE) {

  1254.         do {

  1255.             init_mb(h);

  1256.             decode_mb_i(h,1);

  1257.         } while(next_mb(h));

  1258.     } else if(h->pic_type == FF_P_TYPE) {

  1259.         do {

  1260.             if(h->skip_mode_flag) {

  1261.                 skip_count = get_ue_golomb(&s->gb);

  1262.                 for(i=0;i<skip_count;i++) {

  1263.                     init_mb(h);

  1264.                     mb_skip_p(h);

  1265.                     if(!next_mb(h))

  1266.                         goto done;

  1267.                 }

  1268.                 mb_type = get_ue_golomb(&s->gb) + P_16X16;

  1269.             } else {

  1270.                 mb_type = get_ue_golomb(&s->gb) + P_SKIP;

  1271.             }

  1272.             init_mb(h);

  1273.             if(mb_type > P_8X8) {

  1274.                 h->cbp = cbp_tab[mb_type - P_8X8 - 1][0];

  1275.                 decode_mb_i(h,0);

  1276.             } else {

  1277.                 decode_mb_p(h,mb_type);

  1278.             }

  1279.         } while(next_mb(h));

  1280.     } else { //FF_B_TYPE

  1281.         do {

  1282.             if(h->skip_mode_flag) {

  1283.                 skip_count = get_ue_golomb(&s->gb);

  1284.                 for(i=0;i<skip_count;i++) {

  1285.                     init_mb(h);

  1286.                     mb_skip_b(h);

  1287.                     inter_pred(h);

  1288.                     filter_mb(h,B_SKIP);

  1289.                     if(!next_mb(h))

  1290.                         goto done;

  1291.                 }

  1292.                 mb_type = get_ue_golomb(&s->gb) + B_DIRECT;

  1293.             } else {

  1294.                 mb_type = get_ue_golomb(&s->gb) + B_SKIP;

  1295.             }

  1296.             init_mb(h);

  1297.             if(mb_type > B_8X8) {

  1298.                 h->cbp = cbp_tab[mb_type - B_8X8 - 1][0];

  1299.                 decode_mb_i(h,0);

  1300.             } else {

  1301.                 decode_mb_b(h,mb_type);

  1302.             }

  1303.         } while(next_mb(h));

  1304.     }

  1305.  done:

  1306.     if(h->pic_type != FF_B_TYPE) {

  1307.         if(h->DPB[1].data[0])

  1308.             s->avctx->release_buffer(s->avctx, (AVFrame *)&h->DPB[1]);

  1309.         memcpy(&h->DPB[1], &h->DPB[0], sizeof(Picture));

  1310.         memcpy(&h->DPB[0], &h->picture, sizeof(Picture));

  1311.         memset(&h->picture,0,sizeof(Picture));

  1312.     }

  1313.     return 0;

  1314. }

  1315. 

  1316. /*****************************************************************************

  1317.  *

  1318.  * headers and interface

  1319.  *

  1320.  ****************************************************************************/

  1321. 

  1322. static void init_top_lines(AVSContext *h) {

  1323.     /* alloc top line of predictors */

  1324.     h->top_qp       = av_malloc( h->mb_width);

  1325.     h->top_mv[0]    = av_malloc((h->mb_width*2+1)*sizeof(vector_t));

  1326.     h->top_mv[1]    = av_malloc((h->mb_width*2+1)*sizeof(vector_t));

  1327.     h->top_pred_Y   = av_malloc( h->mb_width*2*sizeof(int));

  1328.     h->top_border_y = av_malloc((h->mb_width+1)*16);

  1329.     h->top_border_u = av_malloc((h->mb_width+1)*8);

  1330.     h->top_border_v = av_malloc((h->mb_width+1)*8);

  1331. 

  1332.     /* alloc space for co-located MVs and types */

  1333.     h->col_mv       = av_malloc( h->mb_width*h->mb_height*4*sizeof(vector_t));

  1334.     h->col_type_base = av_malloc(h->mb_width*h->mb_height);

  1335. }

  1336. 

  1337. static int decode_seq_header(AVSContext *h) {

  1338.     MpegEncContext *s = &h->s;

  1339.     extern const AVRational frame_rate_tab[];

  1340.     int frame_rate_code;

  1341. 

  1342.     h->profile =         get_bits(&s->gb,8);

  1343.     h->level =           get_bits(&s->gb,8);

  1344.     skip_bits1(&s->gb); //progressive sequence

  1345.     s->width =           get_bits(&s->gb,14);

  1346.     s->height =          get_bits(&s->gb,14);

  1347.     skip_bits(&s->gb,2); //chroma format

  1348.     skip_bits(&s->gb,3); //sample_precision

  1349.     h->aspect_ratio =    get_bits(&s->gb,4);

  1350.     frame_rate_code =    get_bits(&s->gb,4);

  1351.     skip_bits(&s->gb,18);//bit_rate_lower

  1352.     skip_bits1(&s->gb);  //marker_bit

  1353.     skip_bits(&s->gb,12);//bit_rate_upper

  1354.     s->low_delay =       get_bits1(&s->gb);

  1355.     h->mb_width  = (s->width  + 15) >> 4;

  1356.     h->mb_height = (s->height + 15) >> 4;

  1357.     h->s.avctx->time_base.den = frame_rate_tab[frame_rate_code].num;

  1358.     h->s.avctx->time_base.num = frame_rate_tab[frame_rate_code].den;

  1359.     h->s.avctx->width  = s->width;

  1360.     h->s.avctx->height = s->height;

  1361.     if(!h->top_qp)

  1362.         init_top_lines(h);

  1363.     return 0;

  1364. }

  1365. 

  1366. /**

  1367.  * finds the end of the current frame in the bitstream.

  1368.  * @return the position of the first byte of the next frame, or -1

  1369.  */

  1370. int ff_cavs_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size) {

  1371.     int pic_found, i;

  1372.     uint32_t state;

  1373. 

  1374.     pic_found= pc->frame_start_found;

  1375.     state= pc->state;

  1376. 

  1377.     i=0;

  1378.     if(!pic_found){

  1379.         for(i=0; i<buf_size; i++){

  1380.             state= (state<<8) | buf[i];

  1381.             if(state == PIC_I_START_CODE || state == PIC_PB_START_CODE){

  1382.                 i++;

  1383.                 pic_found=1;

  1384.                 break;

  1385.             }

  1386.         }

  1387.     }

  1388. 

  1389.     if(pic_found){

  1390.         /* EOF considered as end of frame */

  1391.         if (buf_size == 0)

  1392.             return 0;

  1393.         for(; i<buf_size; i++){

  1394.             state= (state<<8) | buf[i];

  1395.             if((state&0xFFFFFF00) == 0x100){

  1396.                 if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){

  1397.                     pc->frame_start_found=0;

  1398.                     pc->state=-1;

  1399.                     return i-3;

  1400.                 }

  1401.             }

  1402.         }

  1403.     }

  1404.     pc->frame_start_found= pic_found;

  1405.     pc->state= state;

  1406.     return END_NOT_FOUND;

  1407. }

  1408. 

  1409. void ff_cavs_flush(AVCodecContext * avctx) {

  1410.     AVSContext *h = avctx->priv_data;

  1411.     h->got_keyframe = 0;

  1412. }

  1413. 

  1414. static int cavs_decode_frame(AVCodecContext * avctx,void *data, int *data_size,

  1415.                              uint8_t * buf, int buf_size) {

  1416.     AVSContext *h = avctx->priv_data;

  1417.     MpegEncContext *s = &h->s;

  1418.     int input_size;

  1419.     const uint8_t *buf_end;

  1420.     const uint8_t *buf_ptr;

  1421.     AVFrame *picture = data;

  1422.     uint32_t stc;

  1423. 

  1424.     s->avctx = avctx;

  1425. 

  1426.     if (buf_size == 0) {

  1427.         if(!s->low_delay && h->DPB[0].data[0]) {

  1428.             *data_size = sizeof(AVPicture);

  1429.             *picture = *(AVFrame *) &h->DPB[0];

  1430.         }

  1431.         return 0;

  1432.     }

  1433. 

  1434.     buf_ptr = buf;

  1435.     buf_end = buf + buf_size;

  1436.     for(;;) {

  1437.         buf_ptr = ff_find_start_code(buf_ptr,buf_end, &stc);

  1438.         if(stc & 0xFFFFFE00)

  1439.             return FFMAX(0, buf_ptr - buf - s->parse_context.last_index);

  1440.         input_size = (buf_end - buf_ptr)*8;

  1441.         switch(stc) {

  1442.         case SEQ_START_CODE:

  1443.             init_get_bits(&s->gb, buf_ptr, input_size);

  1444.             decode_seq_header(h);

  1445.             break;

  1446.         case PIC_I_START_CODE:

  1447.             if(!h->got_keyframe) {

  1448.                 if(h->DPB[0].data[0])

  1449.                     avctx->release_buffer(avctx, (AVFrame *)&h->DPB[0]);

  1450.                 if(h->DPB[1].data[0])

  1451.                     avctx->release_buffer(avctx, (AVFrame *)&h->DPB[1]);

  1452.                 h->got_keyframe = 1;

  1453.             }

  1454.         case PIC_PB_START_CODE:

  1455.             *data_size = 0;

  1456.             if(!h->got_keyframe)

  1457.                 break;

  1458.             init_get_bits(&s->gb, buf_ptr, input_size);

  1459.             h->stc = stc;

  1460.             if(decode_pic(h))

  1461.                 break;

  1462.             *data_size = sizeof(AVPicture);

  1463.             if(h->pic_type != FF_B_TYPE) {

  1464.                 if(h->DPB[1].data[0]) {

  1465.                     *picture = *(AVFrame *) &h->DPB[1];

  1466.                 } else {

  1467.                     *data_size = 0;

  1468.                 }

  1469.             } else

  1470.                 *picture = *(AVFrame *) &h->picture;

  1471.             break;

  1472.         case EXT_START_CODE:

  1473.             //mpeg_decode_extension(avctx,buf_ptr, input_size);

  1474.             break;

  1475.         case USER_START_CODE:

  1476.             //mpeg_decode_user_data(avctx,buf_ptr, input_size);

  1477.             break;

  1478.         default:

  1479.             if (stc >= SLICE_MIN_START_CODE &&

  1480.                 stc <= SLICE_MAX_START_CODE) {

  1481.                 init_get_bits(&s->gb, buf_ptr, input_size);

  1482.                 decode_slice_header(h, &s->gb);

  1483.             }

  1484.             break;

  1485.         }

  1486.     }

  1487. }

  1488. 

  1489. static int cavs_decode_init(AVCodecContext * avctx) {

  1490.     AVSContext *h = avctx->priv_data;

  1491.     MpegEncContext * const s = &h->s;

  1492. 

  1493.     MPV_decode_defaults(s);

  1494.     s->avctx = avctx;

  1495. 

  1496.     avctx->pix_fmt= PIX_FMT_YUV420P;

  1497. 

  1498.     h->luma_scan[0] = 0;

  1499.     h->luma_scan[1] = 8;

  1500.     h->intra_pred_l[      INTRA_L_VERT] = intra_pred_vert;

  1501.     h->intra_pred_l[     INTRA_L_HORIZ] = intra_pred_horiz;

  1502.     h->intra_pred_l[        INTRA_L_LP] = intra_pred_lp;

  1503.     h->intra_pred_l[ INTRA_L_DOWN_LEFT] = intra_pred_down_left;

  1504.     h->intra_pred_l[INTRA_L_DOWN_RIGHT] = intra_pred_down_right;

  1505.     h->intra_pred_l[   INTRA_L_LP_LEFT] = intra_pred_lp_left;

  1506.     h->intra_pred_l[    INTRA_L_LP_TOP] = intra_pred_lp_top;

  1507.     h->intra_pred_l[    INTRA_L_DC_128] = intra_pred_dc_128;

  1508.     h->intra_pred_c[        INTRA_C_LP] = intra_pred_lp;

  1509.     h->intra_pred_c[     INTRA_C_HORIZ] = intra_pred_horiz;

  1510.     h->intra_pred_c[      INTRA_C_VERT] = intra_pred_vert;

  1511.     h->intra_pred_c[     INTRA_C_PLANE] = intra_pred_plane;

  1512.     h->intra_pred_c[   INTRA_C_LP_LEFT] = intra_pred_lp_left;

  1513.     h->intra_pred_c[    INTRA_C_LP_TOP] = intra_pred_lp_top;

  1514.     h->intra_pred_c[    INTRA_C_DC_128] = intra_pred_dc_128;

  1515.     h->mv[ 7] = un_mv;

  1516.     h->mv[19] = un_mv;

  1517.     return 0;

  1518. }

  1519. 

  1520. static int cavs_decode_end(AVCodecContext * avctx) {

  1521.     AVSContext *h = avctx->priv_data;

  1522. 

  1523.     av_free(h->top_qp);

  1524.     av_free(h->top_mv[0]);

  1525.     av_free(h->top_mv[1]);

  1526.     av_free(h->top_pred_Y);

  1527.     av_free(h->top_border_y);

  1528.     av_free(h->top_border_u);

  1529.     av_free(h->top_border_v);

  1530.     av_free(h->col_mv);

  1531.     av_free(h->col_type_base);

  1532.     return 0;

  1533. }

  1534. 

  1535. AVCodec cavs_decoder = {

  1536.     "cavs",

  1537.     CODEC_TYPE_VIDEO,

  1538.     CODEC_ID_CAVS,

  1539.     sizeof(AVSContext),

  1540.     cavs_decode_init,

  1541.     NULL,

  1542.     cavs_decode_end,

  1543.     cavs_decode_frame,

  1544.     CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY, //FIXME is this correct ?

  1545.     .flush= ff_cavs_flush,

  1546. };