| 
							- /*
 -  * Musepack SV8 decoder
 -  * Copyright (c) 2007 Konstantin Shishkov
 -  *
 -  * This file is part of Libav.
 -  *
 -  * Libav 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.
 -  *
 -  * Libav 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 Libav; if not, write to the Free Software
 -  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 -  */
 - 
 - /**
 -  * @file
 -  * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
 -  * divided into 32 subbands.
 -  */
 - 
 - #include "libavutil/lfg.h"
 - #include "avcodec.h"
 - #include "get_bits.h"
 - #include "dsputil.h"
 - #include "mpegaudiodsp.h"
 - #include "libavutil/audioconvert.h"
 - 
 - #include "mpc.h"
 - #include "mpc8data.h"
 - #include "mpc8huff.h"
 - 
 - static VLC band_vlc, scfi_vlc[2], dscf_vlc[2], res_vlc[2];
 - static VLC q1_vlc, q2_vlc[2], q3_vlc[2], quant_vlc[4][2], q9up_vlc;
 - 
 - static const int q3_offsets[2] = { MPC8_Q3_OFFSET, MPC8_Q4_OFFSET };
 - static const int quant_offsets[6] = { MPC8_Q5_OFFSET, MPC8_Q6_OFFSET, MPC8_Q7_OFFSET, MPC8_Q8_OFFSET };
 - 
 - static inline int mpc8_dec_base(GetBitContext *gb, int k, int n)
 - {
 -     int len = mpc8_cnk_len[k-1][n-1] - 1;
 -     int code = len ? get_bits_long(gb, len) : 0;
 - 
 -     if (code >= mpc8_cnk_lost[k-1][n-1])
 -         code = ((code << 1) | get_bits1(gb)) - mpc8_cnk_lost[k-1][n-1];
 - 
 -     return code;
 - }
 - 
 - static inline int mpc8_dec_enum(GetBitContext *gb, int k, int n)
 - {
 -     int bits = 0;
 -     const uint32_t * C = mpc8_cnk[k-1];
 -     int code = mpc8_dec_base(gb, k, n);
 - 
 -     do {
 -         n--;
 -         if (code >= C[n]) {
 -             bits |= 1 << n;
 -             code -= C[n];
 -             C -= 32;
 -             k--;
 -         }
 -     } while(k > 0);
 - 
 -     return bits;
 - }
 - 
 - static inline int mpc8_get_mod_golomb(GetBitContext *gb, int m)
 - {
 -     if(mpc8_cnk_len[0][m] < 1) return 0;
 -     return mpc8_dec_base(gb, 1, m+1);
 - }
 - 
 - static int mpc8_get_mask(GetBitContext *gb, int size, int t)
 - {
 -     int mask = 0;
 - 
 -     if(t && t != size)
 -          mask = mpc8_dec_enum(gb, FFMIN(t, size - t), size);
 -     if((t << 1) > size) mask = ~mask;
 - 
 -     return mask;
 - }
 - 
 - static const uint16_t vlc_offsets[13] = {
 -     0, 640, 1184, 1748, 2298, 2426, 2554, 3066, 3578, 4106, 4618, 5196, 5708
 - };
 - 
 - static av_cold int mpc8_decode_init(AVCodecContext * avctx)
 - {
 -     int i;
 -     MPCContext *c = avctx->priv_data;
 -     GetBitContext gb;
 -     static int vlc_initialized = 0;
 -     int channels;
 - 
 -     static VLC_TYPE band_table[542][2];
 -     static VLC_TYPE q1_table[520][2];
 -     static VLC_TYPE q9up_table[524][2];
 -     static VLC_TYPE scfi0_table[1 << MPC8_SCFI0_BITS][2];
 -     static VLC_TYPE scfi1_table[1 << MPC8_SCFI1_BITS][2];
 -     static VLC_TYPE dscf0_table[560][2];
 -     static VLC_TYPE dscf1_table[598][2];
 -     static VLC_TYPE q3_0_table[512][2];
 -     static VLC_TYPE q3_1_table[516][2];
 -     static VLC_TYPE codes_table[5708][2];
 - 
 -     if(avctx->extradata_size < 2){
 -         av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
 -         return -1;
 -     }
 -     memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
 -     av_lfg_init(&c->rnd, 0xDEADBEEF);
 -     ff_dsputil_init(&c->dsp, avctx);
 -     ff_mpadsp_init(&c->mpadsp);
 - 
 -     ff_mpc_init();
 - 
 -     init_get_bits(&gb, avctx->extradata, 16);
 - 
 -     skip_bits(&gb, 3);//sample rate
 -     c->maxbands = get_bits(&gb, 5) + 1;
 -     channels = get_bits(&gb, 4) + 1;
 -     if (channels > 2) {
 -         av_log_missing_feature(avctx, "Multichannel MPC SV8", 1);
 -         return -1;
 -     }
 -     c->MSS = get_bits1(&gb);
 -     c->frames = 1 << (get_bits(&gb, 3) * 2);
 - 
 -     avctx->sample_fmt = AV_SAMPLE_FMT_S16;
 -     avctx->channel_layout = (avctx->channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
 - 
 -     if(vlc_initialized) return 0;
 -     av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
 - 
 -     band_vlc.table = band_table;
 -     band_vlc.table_allocated = 542;
 -     init_vlc(&band_vlc, MPC8_BANDS_BITS, MPC8_BANDS_SIZE,
 -              mpc8_bands_bits,  1, 1,
 -              mpc8_bands_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 - 
 -     q1_vlc.table = q1_table;
 -     q1_vlc.table_allocated = 520;
 -     init_vlc(&q1_vlc, MPC8_Q1_BITS, MPC8_Q1_SIZE,
 -              mpc8_q1_bits,  1, 1,
 -              mpc8_q1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 -     q9up_vlc.table = q9up_table;
 -     q9up_vlc.table_allocated = 524;
 -     init_vlc(&q9up_vlc, MPC8_Q9UP_BITS, MPC8_Q9UP_SIZE,
 -              mpc8_q9up_bits,  1, 1,
 -              mpc8_q9up_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 - 
 -     scfi_vlc[0].table = scfi0_table;
 -     scfi_vlc[0].table_allocated = 1 << MPC8_SCFI0_BITS;
 -     init_vlc(&scfi_vlc[0], MPC8_SCFI0_BITS, MPC8_SCFI0_SIZE,
 -              mpc8_scfi0_bits,  1, 1,
 -              mpc8_scfi0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 -     scfi_vlc[1].table = scfi1_table;
 -     scfi_vlc[1].table_allocated = 1 << MPC8_SCFI1_BITS;
 -     init_vlc(&scfi_vlc[1], MPC8_SCFI1_BITS, MPC8_SCFI1_SIZE,
 -              mpc8_scfi1_bits,  1, 1,
 -              mpc8_scfi1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 - 
 -     dscf_vlc[0].table = dscf0_table;
 -     dscf_vlc[0].table_allocated = 560;
 -     init_vlc(&dscf_vlc[0], MPC8_DSCF0_BITS, MPC8_DSCF0_SIZE,
 -              mpc8_dscf0_bits,  1, 1,
 -              mpc8_dscf0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 -     dscf_vlc[1].table = dscf1_table;
 -     dscf_vlc[1].table_allocated = 598;
 -     init_vlc(&dscf_vlc[1], MPC8_DSCF1_BITS, MPC8_DSCF1_SIZE,
 -              mpc8_dscf1_bits,  1, 1,
 -              mpc8_dscf1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 - 
 -     q3_vlc[0].table = q3_0_table;
 -     q3_vlc[0].table_allocated = 512;
 -     ff_init_vlc_sparse(&q3_vlc[0], MPC8_Q3_BITS, MPC8_Q3_SIZE,
 -              mpc8_q3_bits,  1, 1,
 -              mpc8_q3_codes, 1, 1,
 -              mpc8_q3_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
 -     q3_vlc[1].table = q3_1_table;
 -     q3_vlc[1].table_allocated = 516;
 -     ff_init_vlc_sparse(&q3_vlc[1], MPC8_Q4_BITS, MPC8_Q4_SIZE,
 -              mpc8_q4_bits,  1, 1,
 -              mpc8_q4_codes, 1, 1,
 -              mpc8_q4_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
 - 
 -     for(i = 0; i < 2; i++){
 -         res_vlc[i].table = &codes_table[vlc_offsets[0+i]];
 -         res_vlc[i].table_allocated = vlc_offsets[1+i] - vlc_offsets[0+i];
 -         init_vlc(&res_vlc[i], MPC8_RES_BITS, MPC8_RES_SIZE,
 -                  &mpc8_res_bits[i],  1, 1,
 -                  &mpc8_res_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 - 
 -         q2_vlc[i].table = &codes_table[vlc_offsets[2+i]];
 -         q2_vlc[i].table_allocated = vlc_offsets[3+i] - vlc_offsets[2+i];
 -         init_vlc(&q2_vlc[i], MPC8_Q2_BITS, MPC8_Q2_SIZE,
 -                  &mpc8_q2_bits[i],  1, 1,
 -                  &mpc8_q2_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 - 
 -         quant_vlc[0][i].table = &codes_table[vlc_offsets[4+i]];
 -         quant_vlc[0][i].table_allocated = vlc_offsets[5+i] - vlc_offsets[4+i];
 -         init_vlc(&quant_vlc[0][i], MPC8_Q5_BITS, MPC8_Q5_SIZE,
 -                  &mpc8_q5_bits[i],  1, 1,
 -                  &mpc8_q5_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 -         quant_vlc[1][i].table = &codes_table[vlc_offsets[6+i]];
 -         quant_vlc[1][i].table_allocated = vlc_offsets[7+i] - vlc_offsets[6+i];
 -         init_vlc(&quant_vlc[1][i], MPC8_Q6_BITS, MPC8_Q6_SIZE,
 -                  &mpc8_q6_bits[i],  1, 1,
 -                  &mpc8_q6_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 -         quant_vlc[2][i].table = &codes_table[vlc_offsets[8+i]];
 -         quant_vlc[2][i].table_allocated = vlc_offsets[9+i] - vlc_offsets[8+i];
 -         init_vlc(&quant_vlc[2][i], MPC8_Q7_BITS, MPC8_Q7_SIZE,
 -                  &mpc8_q7_bits[i],  1, 1,
 -                  &mpc8_q7_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 -         quant_vlc[3][i].table = &codes_table[vlc_offsets[10+i]];
 -         quant_vlc[3][i].table_allocated = vlc_offsets[11+i] - vlc_offsets[10+i];
 -         init_vlc(&quant_vlc[3][i], MPC8_Q8_BITS, MPC8_Q8_SIZE,
 -                  &mpc8_q8_bits[i],  1, 1,
 -                  &mpc8_q8_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 -     }
 -     vlc_initialized = 1;
 - 
 -     avcodec_get_frame_defaults(&c->frame);
 -     avctx->coded_frame = &c->frame;
 - 
 -     return 0;
 - }
 - 
 - static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
 -                              int *got_frame_ptr, AVPacket *avpkt)
 - {
 -     const uint8_t *buf = avpkt->data;
 -     int buf_size = avpkt->size;
 -     MPCContext *c = avctx->priv_data;
 -     GetBitContext gb2, *gb = &gb2;
 -     int i, j, k, ch, cnt, res, t;
 -     Band *bands = c->bands;
 -     int off;
 -     int maxband, keyframe;
 -     int last[2];
 - 
 -     /* get output buffer */
 -     c->frame.nb_samples = MPC_FRAME_SIZE;
 -     if ((res = avctx->get_buffer(avctx, &c->frame)) < 0) {
 -         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 -         return res;
 -     }
 - 
 -     keyframe = c->cur_frame == 0;
 - 
 -     if(keyframe){
 -         memset(c->Q, 0, sizeof(c->Q));
 -         c->last_bits_used = 0;
 -     }
 -     init_get_bits(gb, buf, buf_size * 8);
 -     skip_bits(gb, c->last_bits_used & 7);
 - 
 -     if(keyframe)
 -         maxband = mpc8_get_mod_golomb(gb, c->maxbands + 1);
 -     else{
 -         maxband = c->last_max_band + get_vlc2(gb, band_vlc.table, MPC8_BANDS_BITS, 2);
 -         if(maxband > 32) maxband -= 33;
 -     }
 -     if(maxband > c->maxbands + 1)
 -         return AVERROR_INVALIDDATA;
 -     c->last_max_band = maxband;
 - 
 -     /* read subband indexes */
 -     if(maxband){
 -         last[0] = last[1] = 0;
 -         for(i = maxband - 1; i >= 0; i--){
 -             for(ch = 0; ch < 2; ch++){
 -                 last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
 -                 if(last[ch] > 15) last[ch] -= 17;
 -                 bands[i].res[ch] = last[ch];
 -             }
 -         }
 -         if(c->MSS){
 -             int mask;
 - 
 -             cnt = 0;
 -             for(i = 0; i < maxband; i++)
 -                 if(bands[i].res[0] || bands[i].res[1])
 -                     cnt++;
 -             t = mpc8_get_mod_golomb(gb, cnt);
 -             mask = mpc8_get_mask(gb, cnt, t);
 -             for(i = maxband - 1; i >= 0; i--)
 -                 if(bands[i].res[0] || bands[i].res[1]){
 -                     bands[i].msf = mask & 1;
 -                     mask >>= 1;
 -                 }
 -         }
 -     }
 -     for(i = maxband; i < c->maxbands; i++)
 -         bands[i].res[0] = bands[i].res[1] = 0;
 - 
 -     if(keyframe){
 -         for(i = 0; i < 32; i++)
 -             c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
 -     }
 - 
 -     for(i = 0; i < maxband; i++){
 -         if(bands[i].res[0] || bands[i].res[1]){
 -             cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
 -             if(cnt >= 0){
 -                 t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
 -                 if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
 -                 if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
 -             }
 -         }
 -     }
 - 
 -     for(i = 0; i < maxband; i++){
 -         for(ch = 0; ch < 2; ch++){
 -             if(!bands[i].res[ch]) continue;
 - 
 -             if(c->oldDSCF[ch][i]){
 -                 bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
 -                 c->oldDSCF[ch][i] = 0;
 -             }else{
 -                 t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
 -                 if(t == 64)
 -                     t += get_bits(gb, 6);
 -                 bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
 -             }
 -             for(j = 0; j < 2; j++){
 -                 if((bands[i].scfi[ch] << j) & 2)
 -                     bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
 -                 else{
 -                     t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
 -                     if(t == 31)
 -                         t = 64 + get_bits(gb, 6);
 -                     bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
 -                 }
 -             }
 -         }
 -     }
 - 
 -     for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
 -         for(ch = 0; ch < 2; ch++){
 -             res = bands[i].res[ch];
 -             switch(res){
 -             case -1:
 -                 for(j = 0; j < SAMPLES_PER_BAND; j++)
 -                     c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
 -                 break;
 -             case 0:
 -                 break;
 -             case 1:
 -                 for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
 -                     cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
 -                     t = mpc8_get_mask(gb, 18, cnt);
 -                     for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
 -                         c->Q[ch][off + j + k] = (t & 0x20000) ? (get_bits1(gb) << 1) - 1 : 0;
 -                 }
 -                 break;
 -             case 2:
 -                 cnt = 6;//2*mpc8_thres[res]
 -                 for(j = 0; j < SAMPLES_PER_BAND; j += 3){
 -                     t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
 -                     c->Q[ch][off + j + 0] = mpc8_idx50[t];
 -                     c->Q[ch][off + j + 1] = mpc8_idx51[t];
 -                     c->Q[ch][off + j + 2] = mpc8_idx52[t];
 -                     cnt = (cnt >> 1) + mpc8_huffq2[t];
 -                 }
 -                 break;
 -             case 3:
 -             case 4:
 -                 for(j = 0; j < SAMPLES_PER_BAND; j += 2){
 -                     t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
 -                     c->Q[ch][off + j + 1] = t >> 4;
 -                     c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
 -                 }
 -                 break;
 -             case 5:
 -             case 6:
 -             case 7:
 -             case 8:
 -                 cnt = 2 * mpc8_thres[res];
 -                 for(j = 0; j < SAMPLES_PER_BAND; j++){
 -                     t = get_vlc2(gb, quant_vlc[res - 5][cnt > mpc8_thres[res]].table, quant_vlc[res - 5][cnt > mpc8_thres[res]].bits, 2) + quant_offsets[res - 5];
 -                     c->Q[ch][off + j] = t;
 -                     cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
 -                 }
 -                 break;
 -             default:
 -                 for(j = 0; j < SAMPLES_PER_BAND; j++){
 -                     c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
 -                     if(res != 9){
 -                         c->Q[ch][off + j] <<= res - 9;
 -                         c->Q[ch][off + j] |= get_bits(gb, res - 9);
 -                     }
 -                     c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
 -                 }
 -             }
 -         }
 -     }
 - 
 -     ff_mpc_dequantize_and_synth(c, maxband - 1, c->frame.data[0],
 -                                 avctx->channels);
 - 
 -     c->cur_frame++;
 - 
 -     c->last_bits_used = get_bits_count(gb);
 -     if(get_bits_left(gb) < 8) // we have only padding left
 -         c->last_bits_used = buf_size << 3;
 -     if(c->cur_frame >= c->frames)
 -         c->cur_frame = 0;
 - 
 -     *got_frame_ptr   = 1;
 -     *(AVFrame *)data = c->frame;
 - 
 -     return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
 - }
 - 
 - static av_cold void mpc8_decode_flush(AVCodecContext *avctx)
 - {
 -     MPCContext *c = avctx->priv_data;
 -     c->cur_frame = 0;
 - }
 - 
 - AVCodec ff_mpc8_decoder = {
 -     .name           = "mpc8",
 -     .type           = AVMEDIA_TYPE_AUDIO,
 -     .id             = AV_CODEC_ID_MUSEPACK8,
 -     .priv_data_size = sizeof(MPCContext),
 -     .init           = mpc8_decode_init,
 -     .decode         = mpc8_decode_frame,
 -     .flush          = mpc8_decode_flush,
 -     .capabilities   = CODEC_CAP_DR1,
 -     .long_name      = NULL_IF_CONFIG_SMALL("Musepack SV8"),
 - };
 
 
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