FFmpeg: libavcodec/mpc8.c Source File

00001 /*
00002  * Musepack SV8 decoder
00003  * Copyright (c) 2007 Konstantin Shishkov
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00028 #include "libavutil/lfg.h"
00029 #include "avcodec.h"
00030 #include "get_bits.h"
00031 #include "dsputil.h"
00032 #include "mpegaudiodsp.h"
00033 #include "libavutil/audioconvert.h"
00034 
00035 #include "mpc.h"
00036 #include "mpc8data.h"
00037 #include "mpc8huff.h"
00038 
00039 static VLC band_vlc, scfi_vlc[2], dscf_vlc[2], res_vlc[2];
00040 static VLC q1_vlc, q2_vlc[2], q3_vlc[2], quant_vlc[4][2], q9up_vlc;
00041 
00042 static const int q3_offsets[2] = { MPC8_Q3_OFFSET, MPC8_Q4_OFFSET };
00043 static const int quant_offsets[6] = { MPC8_Q5_OFFSET, MPC8_Q6_OFFSET, MPC8_Q7_OFFSET, MPC8_Q8_OFFSET };
00044 
00045 static inline int mpc8_dec_base(GetBitContext *gb, int k, int n)
00046 {
00047     int len = mpc8_cnk_len[k-1][n-1] - 1;
00048     int code = len ? get_bits_long(gb, len) : 0;
00049 
00050     if (code >= mpc8_cnk_lost[k-1][n-1])
00051         code = ((code << 1) | get_bits1(gb)) - mpc8_cnk_lost[k-1][n-1];
00052 
00053     return code;
00054 }
00055 
00056 static inline int mpc8_dec_enum(GetBitContext *gb, int k, int n)
00057 {
00058     int bits = 0;
00059     const uint32_t * C = mpc8_cnk[k-1];
00060     int code = mpc8_dec_base(gb, k, n);
00061 
00062     do {
00063         n--;
00064         if (code >= C[n]) {
00065             bits |= 1 << n;
00066             code -= C[n];
00067             C -= 32;
00068             k--;
00069         }
00070     } while(k > 0);
00071 
00072     return bits;
00073 }
00074 
00075 static inline int mpc8_get_mod_golomb(GetBitContext *gb, int m)
00076 {
00077     if(mpc8_cnk_len[0][m] < 1) return 0;
00078     return mpc8_dec_base(gb, 1, m+1);
00079 }
00080 
00081 static int mpc8_get_mask(GetBitContext *gb, int size, int t)
00082 {
00083     int mask = 0;
00084 
00085     if(t && t != size)
00086          mask = mpc8_dec_enum(gb, FFMIN(t, size - t), size);
00087     if((t << 1) > size) mask = ~mask;
00088 
00089     return mask;
00090 }
00091 
00092 static const uint16_t vlc_offsets[13] = {
00093     0, 640, 1184, 1748, 2298, 2426, 2554, 3066, 3578, 4106, 4618, 5196, 5708
00094 };
00095 
00096 static av_cold int mpc8_decode_init(AVCodecContext * avctx)
00097 {
00098     int i;
00099     MPCContext *c = avctx->priv_data;
00100     GetBitContext gb;
00101     static int vlc_initialized = 0;
00102     int channels;
00103 
00104     static VLC_TYPE band_table[542][2];
00105     static VLC_TYPE q1_table[520][2];
00106     static VLC_TYPE q9up_table[524][2];
00107     static VLC_TYPE scfi0_table[1 << MPC8_SCFI0_BITS][2];
00108     static VLC_TYPE scfi1_table[1 << MPC8_SCFI1_BITS][2];
00109     static VLC_TYPE dscf0_table[560][2];
00110     static VLC_TYPE dscf1_table[598][2];
00111     static VLC_TYPE q3_0_table[512][2];
00112     static VLC_TYPE q3_1_table[516][2];
00113     static VLC_TYPE codes_table[5708][2];
00114 
00115     if(avctx->extradata_size < 2){
00116         av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
00117         return -1;
00118     }
00119     memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
00120     av_lfg_init(&c->rnd, 0xDEADBEEF);
00121     dsputil_init(&c->dsp, avctx);
00122     ff_mpadsp_init(&c->mpadsp);
00123 
00124     ff_mpc_init();
00125 
00126     init_get_bits(&gb, avctx->extradata, 16);
00127 
00128     skip_bits(&gb, 3);//sample rate
00129     c->maxbands = get_bits(&gb, 5) + 1;
00130     if (c->maxbands >= BANDS)
00131         return AVERROR_INVALIDDATA;
00132     channels = get_bits(&gb, 4) + 1;
00133     if (channels > 2) {
00134         av_log_missing_feature(avctx, "Multichannel MPC SV8", 1);
00135         return -1;
00136     }
00137     c->MSS = get_bits1(&gb);
00138     c->frames = 1 << (get_bits(&gb, 3) * 2);
00139 
00140     avctx->sample_fmt = AV_SAMPLE_FMT_S16;
00141     avctx->channel_layout = (channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
00142     avctx->channels = channels;
00143 
00144     if(vlc_initialized) return 0;
00145     av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
00146 
00147     band_vlc.table = band_table;
00148     band_vlc.table_allocated = 542;
00149     init_vlc(&band_vlc, MPC8_BANDS_BITS, MPC8_BANDS_SIZE,
00150              mpc8_bands_bits,  1, 1,
00151              mpc8_bands_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00152 
00153     q1_vlc.table = q1_table;
00154     q1_vlc.table_allocated = 520;
00155     init_vlc(&q1_vlc, MPC8_Q1_BITS, MPC8_Q1_SIZE,
00156              mpc8_q1_bits,  1, 1,
00157              mpc8_q1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00158     q9up_vlc.table = q9up_table;
00159     q9up_vlc.table_allocated = 524;
00160     init_vlc(&q9up_vlc, MPC8_Q9UP_BITS, MPC8_Q9UP_SIZE,
00161              mpc8_q9up_bits,  1, 1,
00162              mpc8_q9up_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00163 
00164     scfi_vlc[0].table = scfi0_table;
00165     scfi_vlc[0].table_allocated = 1 << MPC8_SCFI0_BITS;
00166     init_vlc(&scfi_vlc[0], MPC8_SCFI0_BITS, MPC8_SCFI0_SIZE,
00167              mpc8_scfi0_bits,  1, 1,
00168              mpc8_scfi0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00169     scfi_vlc[1].table = scfi1_table;
00170     scfi_vlc[1].table_allocated = 1 << MPC8_SCFI1_BITS;
00171     init_vlc(&scfi_vlc[1], MPC8_SCFI1_BITS, MPC8_SCFI1_SIZE,
00172              mpc8_scfi1_bits,  1, 1,
00173              mpc8_scfi1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00174 
00175     dscf_vlc[0].table = dscf0_table;
00176     dscf_vlc[0].table_allocated = 560;
00177     init_vlc(&dscf_vlc[0], MPC8_DSCF0_BITS, MPC8_DSCF0_SIZE,
00178              mpc8_dscf0_bits,  1, 1,
00179              mpc8_dscf0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00180     dscf_vlc[1].table = dscf1_table;
00181     dscf_vlc[1].table_allocated = 598;
00182     init_vlc(&dscf_vlc[1], MPC8_DSCF1_BITS, MPC8_DSCF1_SIZE,
00183              mpc8_dscf1_bits,  1, 1,
00184              mpc8_dscf1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00185 
00186     q3_vlc[0].table = q3_0_table;
00187     q3_vlc[0].table_allocated = 512;
00188     ff_init_vlc_sparse(&q3_vlc[0], MPC8_Q3_BITS, MPC8_Q3_SIZE,
00189              mpc8_q3_bits,  1, 1,
00190              mpc8_q3_codes, 1, 1,
00191              mpc8_q3_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
00192     q3_vlc[1].table = q3_1_table;
00193     q3_vlc[1].table_allocated = 516;
00194     ff_init_vlc_sparse(&q3_vlc[1], MPC8_Q4_BITS, MPC8_Q4_SIZE,
00195              mpc8_q4_bits,  1, 1,
00196              mpc8_q4_codes, 1, 1,
00197              mpc8_q4_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
00198 
00199     for(i = 0; i < 2; i++){
00200         res_vlc[i].table = &codes_table[vlc_offsets[0+i]];
00201         res_vlc[i].table_allocated = vlc_offsets[1+i] - vlc_offsets[0+i];
00202         init_vlc(&res_vlc[i], MPC8_RES_BITS, MPC8_RES_SIZE,
00203                  &mpc8_res_bits[i],  1, 1,
00204                  &mpc8_res_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
00205 
00206         q2_vlc[i].table = &codes_table[vlc_offsets[2+i]];
00207         q2_vlc[i].table_allocated = vlc_offsets[3+i] - vlc_offsets[2+i];
00208         init_vlc(&q2_vlc[i], MPC8_Q2_BITS, MPC8_Q2_SIZE,
00209                  &mpc8_q2_bits[i],  1, 1,
00210                  &mpc8_q2_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
00211 
00212         quant_vlc[0][i].table = &codes_table[vlc_offsets[4+i]];
00213         quant_vlc[0][i].table_allocated = vlc_offsets[5+i] - vlc_offsets[4+i];
00214         init_vlc(&quant_vlc[0][i], MPC8_Q5_BITS, MPC8_Q5_SIZE,
00215                  &mpc8_q5_bits[i],  1, 1,
00216                  &mpc8_q5_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
00217         quant_vlc[1][i].table = &codes_table[vlc_offsets[6+i]];
00218         quant_vlc[1][i].table_allocated = vlc_offsets[7+i] - vlc_offsets[6+i];
00219         init_vlc(&quant_vlc[1][i], MPC8_Q6_BITS, MPC8_Q6_SIZE,
00220                  &mpc8_q6_bits[i],  1, 1,
00221                  &mpc8_q6_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
00222         quant_vlc[2][i].table = &codes_table[vlc_offsets[8+i]];
00223         quant_vlc[2][i].table_allocated = vlc_offsets[9+i] - vlc_offsets[8+i];
00224         init_vlc(&quant_vlc[2][i], MPC8_Q7_BITS, MPC8_Q7_SIZE,
00225                  &mpc8_q7_bits[i],  1, 1,
00226                  &mpc8_q7_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
00227         quant_vlc[3][i].table = &codes_table[vlc_offsets[10+i]];
00228         quant_vlc[3][i].table_allocated = vlc_offsets[11+i] - vlc_offsets[10+i];
00229         init_vlc(&quant_vlc[3][i], MPC8_Q8_BITS, MPC8_Q8_SIZE,
00230                  &mpc8_q8_bits[i],  1, 1,
00231                  &mpc8_q8_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
00232     }
00233     vlc_initialized = 1;
00234 
00235     avcodec_get_frame_defaults(&c->frame);
00236     avctx->coded_frame = &c->frame;
00237 
00238     return 0;
00239 }
00240 
00241 static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
00242                              int *got_frame_ptr, AVPacket *avpkt)
00243 {
00244     const uint8_t *buf = avpkt->data;
00245     int buf_size = avpkt->size;
00246     MPCContext *c = avctx->priv_data;
00247     GetBitContext gb2, *gb = &gb2;
00248     int i, j, k, ch, cnt, res, t;
00249     Band *bands = c->bands;
00250     int off;
00251     int maxband, keyframe;
00252     int last[2];
00253 
00254     /* get output buffer */
00255     c->frame.nb_samples = MPC_FRAME_SIZE;
00256     if ((res = avctx->get_buffer(avctx, &c->frame)) < 0) {
00257         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00258         return res;
00259     }
00260 
00261     keyframe = c->cur_frame == 0;
00262 
00263     if(keyframe){
00264         memset(c->Q, 0, sizeof(c->Q));
00265         c->last_bits_used = 0;
00266     }
00267     init_get_bits(gb, buf, buf_size * 8);
00268     skip_bits(gb, c->last_bits_used & 7);
00269 
00270     if(keyframe)
00271         maxband = mpc8_get_mod_golomb(gb, c->maxbands + 1);
00272     else{
00273         maxband = c->last_max_band + get_vlc2(gb, band_vlc.table, MPC8_BANDS_BITS, 2);
00274         if(maxband > 32) maxband -= 33;
00275     }
00276     if(maxband > c->maxbands)
00277         return AVERROR_INVALIDDATA;
00278     c->last_max_band = maxband;
00279 
00280     /* read subband indexes */
00281     if(maxband){
00282         last[0] = last[1] = 0;
00283         for(i = maxband - 1; i >= 0; i--){
00284             for(ch = 0; ch < 2; ch++){
00285                 last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
00286                 if(last[ch] > 15) last[ch] -= 17;
00287                 bands[i].res[ch] = last[ch];
00288             }
00289         }
00290         if(c->MSS){
00291             int mask;
00292 
00293             cnt = 0;
00294             for(i = 0; i < maxband; i++)
00295                 if(bands[i].res[0] || bands[i].res[1])
00296                     cnt++;
00297             t = mpc8_get_mod_golomb(gb, cnt);
00298             mask = mpc8_get_mask(gb, cnt, t);
00299             for(i = maxband - 1; i >= 0; i--)
00300                 if(bands[i].res[0] || bands[i].res[1]){
00301                     bands[i].msf = mask & 1;
00302                     mask >>= 1;
00303                 }
00304         }
00305     }
00306     for(i = maxband; i < c->maxbands; i++)
00307         bands[i].res[0] = bands[i].res[1] = 0;
00308 
00309     if(keyframe){
00310         for(i = 0; i < 32; i++)
00311             c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
00312     }
00313 
00314     for(i = 0; i < maxband; i++){
00315         if(bands[i].res[0] || bands[i].res[1]){
00316             cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
00317             if(cnt >= 0){
00318                 t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
00319                 if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
00320                 if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
00321             }
00322         }
00323     }
00324 
00325     for(i = 0; i < maxband; i++){
00326         for(ch = 0; ch < 2; ch++){
00327             if(!bands[i].res[ch]) continue;
00328 
00329             if(c->oldDSCF[ch][i]){
00330                 bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
00331                 c->oldDSCF[ch][i] = 0;
00332             }else{
00333                 t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
00334                 if(t == 64)
00335                     t += get_bits(gb, 6);
00336                 bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
00337             }
00338             for(j = 0; j < 2; j++){
00339                 if((bands[i].scfi[ch] << j) & 2)
00340                     bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
00341                 else{
00342                     t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
00343                     if(t == 31)
00344                         t = 64 + get_bits(gb, 6);
00345                     bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
00346                 }
00347             }
00348         }
00349     }
00350 
00351     for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
00352         for(ch = 0; ch < 2; ch++){
00353             res = bands[i].res[ch];
00354             switch(res){
00355             case -1:
00356                 for(j = 0; j < SAMPLES_PER_BAND; j++)
00357                     c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
00358                 break;
00359             case 0:
00360                 break;
00361             case 1:
00362                 for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
00363                     cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
00364                     t = mpc8_get_mask(gb, 18, cnt);
00365                     for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
00366                         c->Q[ch][off + j + k] = (t & 0x20000) ? (get_bits1(gb) << 1) - 1 : 0;
00367                 }
00368                 break;
00369             case 2:
00370                 cnt = 6;//2*mpc8_thres[res]
00371                 for(j = 0; j < SAMPLES_PER_BAND; j += 3){
00372                     t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
00373                     c->Q[ch][off + j + 0] = mpc8_idx50[t];
00374                     c->Q[ch][off + j + 1] = mpc8_idx51[t];
00375                     c->Q[ch][off + j + 2] = mpc8_idx52[t];
00376                     cnt = (cnt >> 1) + mpc8_huffq2[t];
00377                 }
00378                 break;
00379             case 3:
00380             case 4:
00381                 for(j = 0; j < SAMPLES_PER_BAND; j += 2){
00382                     t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
00383                     c->Q[ch][off + j + 1] = t >> 4;
00384                     c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
00385                 }
00386                 break;
00387             case 5:
00388             case 6:
00389             case 7:
00390             case 8:
00391                 cnt = 2 * mpc8_thres[res];
00392                 for(j = 0; j < SAMPLES_PER_BAND; j++){
00393                     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];
00394                     c->Q[ch][off + j] = t;
00395                     cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
00396                 }
00397                 break;
00398             default:
00399                 for(j = 0; j < SAMPLES_PER_BAND; j++){
00400                     c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
00401                     if(res != 9){
00402                         c->Q[ch][off + j] <<= res - 9;
00403                         c->Q[ch][off + j] |= get_bits(gb, res - 9);
00404                     }
00405                     c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
00406                 }
00407             }
00408         }
00409     }
00410 
00411     ff_mpc_dequantize_and_synth(c, maxband, c->frame.data[0], avctx->channels);
00412 
00413     c->cur_frame++;
00414 
00415     c->last_bits_used = get_bits_count(gb);
00416     if(c->cur_frame >= c->frames)
00417         c->cur_frame = 0;
00418 
00419     *got_frame_ptr   = 1;
00420     *(AVFrame *)data = c->frame;
00421 
00422     return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
00423 }
00424 
00425 AVCodec ff_mpc8_decoder = {
00426     .name           = "mpc8",
00427     .type           = AVMEDIA_TYPE_AUDIO,
00428     .id             = CODEC_ID_MUSEPACK8,
00429     .priv_data_size = sizeof(MPCContext),
00430     .init           = mpc8_decode_init,
00431     .decode         = mpc8_decode_frame,
00432     .capabilities   = CODEC_CAP_DR1,
00433     .long_name = NULL_IF_CONFIG_SMALL("Musepack SV8"),
00434 };