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     ff_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         av_log(avctx,AV_LOG_ERROR, "maxbands %d too high\n", c->maxbands);
00132         return AVERROR_INVALIDDATA;
00133     }
00134     channels = get_bits(&gb, 4) + 1;
00135     if (channels > 2) {
00136         av_log_missing_feature(avctx, "Multichannel MPC SV8", 1);
00137         return -1;
00138     }
00139     c->MSS = get_bits1(&gb);
00140     c->frames = 1 << (get_bits(&gb, 3) * 2);
00141 
00142     avctx->sample_fmt = AV_SAMPLE_FMT_S16;
00143     avctx->channel_layout = (avctx->channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
00144 
00145     if(vlc_initialized) return 0;
00146     av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
00147 
00148     band_vlc.table = band_table;
00149     band_vlc.table_allocated = 542;
00150     init_vlc(&band_vlc, MPC8_BANDS_BITS, MPC8_BANDS_SIZE,
00151              mpc8_bands_bits,  1, 1,
00152              mpc8_bands_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00153 
00154     q1_vlc.table = q1_table;
00155     q1_vlc.table_allocated = 520;
00156     init_vlc(&q1_vlc, MPC8_Q1_BITS, MPC8_Q1_SIZE,
00157              mpc8_q1_bits,  1, 1,
00158              mpc8_q1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00159     q9up_vlc.table = q9up_table;
00160     q9up_vlc.table_allocated = 524;
00161     init_vlc(&q9up_vlc, MPC8_Q9UP_BITS, MPC8_Q9UP_SIZE,
00162              mpc8_q9up_bits,  1, 1,
00163              mpc8_q9up_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00164 
00165     scfi_vlc[0].table = scfi0_table;
00166     scfi_vlc[0].table_allocated = 1 << MPC8_SCFI0_BITS;
00167     init_vlc(&scfi_vlc[0], MPC8_SCFI0_BITS, MPC8_SCFI0_SIZE,
00168              mpc8_scfi0_bits,  1, 1,
00169              mpc8_scfi0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00170     scfi_vlc[1].table = scfi1_table;
00171     scfi_vlc[1].table_allocated = 1 << MPC8_SCFI1_BITS;
00172     init_vlc(&scfi_vlc[1], MPC8_SCFI1_BITS, MPC8_SCFI1_SIZE,
00173              mpc8_scfi1_bits,  1, 1,
00174              mpc8_scfi1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00175 
00176     dscf_vlc[0].table = dscf0_table;
00177     dscf_vlc[0].table_allocated = 560;
00178     init_vlc(&dscf_vlc[0], MPC8_DSCF0_BITS, MPC8_DSCF0_SIZE,
00179              mpc8_dscf0_bits,  1, 1,
00180              mpc8_dscf0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00181     dscf_vlc[1].table = dscf1_table;
00182     dscf_vlc[1].table_allocated = 598;
00183     init_vlc(&dscf_vlc[1], MPC8_DSCF1_BITS, MPC8_DSCF1_SIZE,
00184              mpc8_dscf1_bits,  1, 1,
00185              mpc8_dscf1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
00186 
00187     q3_vlc[0].table = q3_0_table;
00188     q3_vlc[0].table_allocated = 512;
00189     ff_init_vlc_sparse(&q3_vlc[0], MPC8_Q3_BITS, MPC8_Q3_SIZE,
00190              mpc8_q3_bits,  1, 1,
00191              mpc8_q3_codes, 1, 1,
00192              mpc8_q3_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
00193     q3_vlc[1].table = q3_1_table;
00194     q3_vlc[1].table_allocated = 516;
00195     ff_init_vlc_sparse(&q3_vlc[1], MPC8_Q4_BITS, MPC8_Q4_SIZE,
00196              mpc8_q4_bits,  1, 1,
00197              mpc8_q4_codes, 1, 1,
00198              mpc8_q4_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
00199 
00200     for(i = 0; i < 2; i++){
00201         res_vlc[i].table = &codes_table[vlc_offsets[0+i]];
00202         res_vlc[i].table_allocated = vlc_offsets[1+i] - vlc_offsets[0+i];
00203         init_vlc(&res_vlc[i], MPC8_RES_BITS, MPC8_RES_SIZE,
00204                  &mpc8_res_bits[i],  1, 1,
00205                  &mpc8_res_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
00206 
00207         q2_vlc[i].table = &codes_table[vlc_offsets[2+i]];
00208         q2_vlc[i].table_allocated = vlc_offsets[3+i] - vlc_offsets[2+i];
00209         init_vlc(&q2_vlc[i], MPC8_Q2_BITS, MPC8_Q2_SIZE,
00210                  &mpc8_q2_bits[i],  1, 1,
00211                  &mpc8_q2_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
00212 
00213         quant_vlc[0][i].table = &codes_table[vlc_offsets[4+i]];
00214         quant_vlc[0][i].table_allocated = vlc_offsets[5+i] - vlc_offsets[4+i];
00215         init_vlc(&quant_vlc[0][i], MPC8_Q5_BITS, MPC8_Q5_SIZE,
00216                  &mpc8_q5_bits[i],  1, 1,
00217                  &mpc8_q5_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
00218         quant_vlc[1][i].table = &codes_table[vlc_offsets[6+i]];
00219         quant_vlc[1][i].table_allocated = vlc_offsets[7+i] - vlc_offsets[6+i];
00220         init_vlc(&quant_vlc[1][i], MPC8_Q6_BITS, MPC8_Q6_SIZE,
00221                  &mpc8_q6_bits[i],  1, 1,
00222                  &mpc8_q6_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
00223         quant_vlc[2][i].table = &codes_table[vlc_offsets[8+i]];
00224         quant_vlc[2][i].table_allocated = vlc_offsets[9+i] - vlc_offsets[8+i];
00225         init_vlc(&quant_vlc[2][i], MPC8_Q7_BITS, MPC8_Q7_SIZE,
00226                  &mpc8_q7_bits[i],  1, 1,
00227                  &mpc8_q7_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
00228         quant_vlc[3][i].table = &codes_table[vlc_offsets[10+i]];
00229         quant_vlc[3][i].table_allocated = vlc_offsets[11+i] - vlc_offsets[10+i];
00230         init_vlc(&quant_vlc[3][i], MPC8_Q8_BITS, MPC8_Q8_SIZE,
00231                  &mpc8_q8_bits[i],  1, 1,
00232                  &mpc8_q8_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
00233     }
00234     vlc_initialized = 1;
00235 
00236     avcodec_get_frame_defaults(&c->frame);
00237     avctx->coded_frame = &c->frame;
00238 
00239     return 0;
00240 }
00241 
00242 static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
00243                              int *got_frame_ptr, AVPacket *avpkt)
00244 {
00245     const uint8_t *buf = avpkt->data;
00246     int buf_size = avpkt->size;
00247     MPCContext *c = avctx->priv_data;
00248     GetBitContext gb2, *gb = &gb2;
00249     int i, j, k, ch, cnt, res, t;
00250     Band *bands = c->bands;
00251     int off;
00252     int maxband, keyframe;
00253     int last[2];
00254 
00255     /* get output buffer */
00256     c->frame.nb_samples = MPC_FRAME_SIZE;
00257     if ((res = avctx->get_buffer(avctx, &c->frame)) < 0) {
00258         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00259         return res;
00260     }
00261 
00262     keyframe = c->cur_frame == 0;
00263 
00264     if(keyframe){
00265         memset(c->Q, 0, sizeof(c->Q));
00266         c->last_bits_used = 0;
00267     }
00268     init_get_bits(gb, buf, buf_size * 8);
00269     skip_bits(gb, c->last_bits_used & 7);
00270 
00271     if(keyframe)
00272         maxband = mpc8_get_mod_golomb(gb, c->maxbands + 1);
00273     else{
00274         maxband = c->last_max_band + get_vlc2(gb, band_vlc.table, MPC8_BANDS_BITS, 2);
00275         if(maxband > 32) maxband -= 33;
00276     }
00277     if(maxband >= BANDS) {
00278         av_log(avctx, AV_LOG_ERROR, "maxband %d too large\n",maxband);
00279         return AVERROR_INVALIDDATA;
00280     }
00281     c->last_max_band = maxband;
00282 
00283     /* read subband indexes */
00284     if(maxband){
00285         last[0] = last[1] = 0;
00286         for(i = maxband - 1; i >= 0; i--){
00287             for(ch = 0; ch < 2; ch++){
00288                 last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
00289                 if(last[ch] > 15) last[ch] -= 17;
00290                 bands[i].res[ch] = last[ch];
00291             }
00292         }
00293         if(c->MSS){
00294             int mask;
00295 
00296             cnt = 0;
00297             for(i = 0; i < maxband; i++)
00298                 if(bands[i].res[0] || bands[i].res[1])
00299                     cnt++;
00300             t = mpc8_get_mod_golomb(gb, cnt);
00301             mask = mpc8_get_mask(gb, cnt, t);
00302             for(i = maxband - 1; i >= 0; i--)
00303                 if(bands[i].res[0] || bands[i].res[1]){
00304                     bands[i].msf = mask & 1;
00305                     mask >>= 1;
00306                 }
00307         }
00308     }
00309     for(i = maxband; i < c->maxbands; i++)
00310         bands[i].res[0] = bands[i].res[1] = 0;
00311 
00312     if(keyframe){
00313         for(i = 0; i < 32; i++)
00314             c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
00315     }
00316 
00317     for(i = 0; i < maxband; i++){
00318         if(bands[i].res[0] || bands[i].res[1]){
00319             cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
00320             if(cnt >= 0){
00321                 t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
00322                 if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
00323                 if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
00324             }
00325         }
00326     }
00327 
00328     for(i = 0; i < maxband; i++){
00329         for(ch = 0; ch < 2; ch++){
00330             if(!bands[i].res[ch]) continue;
00331 
00332             if(c->oldDSCF[ch][i]){
00333                 bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
00334                 c->oldDSCF[ch][i] = 0;
00335             }else{
00336                 t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
00337                 if(t == 64)
00338                     t += get_bits(gb, 6);
00339                 bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
00340             }
00341             for(j = 0; j < 2; j++){
00342                 if((bands[i].scfi[ch] << j) & 2)
00343                     bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
00344                 else{
00345                     t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
00346                     if(t == 31)
00347                         t = 64 + get_bits(gb, 6);
00348                     bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
00349                 }
00350             }
00351         }
00352     }
00353 
00354     for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
00355         for(ch = 0; ch < 2; ch++){
00356             res = bands[i].res[ch];
00357             switch(res){
00358             case -1:
00359                 for(j = 0; j < SAMPLES_PER_BAND; j++)
00360                     c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
00361                 break;
00362             case 0:
00363                 break;
00364             case 1:
00365                 for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
00366                     cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
00367                     t = mpc8_get_mask(gb, 18, cnt);
00368                     for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
00369                         c->Q[ch][off + j + k] = (t & 0x20000) ? (get_bits1(gb) << 1) - 1 : 0;
00370                 }
00371                 break;
00372             case 2:
00373                 cnt = 6;//2*mpc8_thres[res]
00374                 for(j = 0; j < SAMPLES_PER_BAND; j += 3){
00375                     t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
00376                     c->Q[ch][off + j + 0] = mpc8_idx50[t];
00377                     c->Q[ch][off + j + 1] = mpc8_idx51[t];
00378                     c->Q[ch][off + j + 2] = mpc8_idx52[t];
00379                     cnt = (cnt >> 1) + mpc8_huffq2[t];
00380                 }
00381                 break;
00382             case 3:
00383             case 4:
00384                 for(j = 0; j < SAMPLES_PER_BAND; j += 2){
00385                     t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
00386                     c->Q[ch][off + j + 1] = t >> 4;
00387                     c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
00388                 }
00389                 break;
00390             case 5:
00391             case 6:
00392             case 7:
00393             case 8:
00394                 cnt = 2 * mpc8_thres[res];
00395                 for(j = 0; j < SAMPLES_PER_BAND; j++){
00396                     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];
00397                     c->Q[ch][off + j] = t;
00398                     cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
00399                 }
00400                 break;
00401             default:
00402                 for(j = 0; j < SAMPLES_PER_BAND; j++){
00403                     c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
00404                     if(res != 9){
00405                         c->Q[ch][off + j] <<= res - 9;
00406                         c->Q[ch][off + j] |= get_bits(gb, res - 9);
00407                     }
00408                     c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
00409                 }
00410             }
00411         }
00412     }
00413 
00414     ff_mpc_dequantize_and_synth(c, maxband, c->frame.data[0], avctx->channels);
00415 
00416     c->cur_frame++;
00417 
00418     c->last_bits_used = get_bits_count(gb);
00419     if(c->cur_frame >= c->frames)
00420         c->cur_frame = 0;
00421 
00422     *got_frame_ptr   = 1;
00423     *(AVFrame *)data = c->frame;
00424 
00425     return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
00426 }
00427 
00428 AVCodec ff_mpc8_decoder = {
00429     .name           = "mpc8",
00430     .type           = AVMEDIA_TYPE_AUDIO,
00431     .id             = CODEC_ID_MUSEPACK8,
00432     .priv_data_size = sizeof(MPCContext),
00433     .init           = mpc8_decode_init,
00434     .decode         = mpc8_decode_frame,
00435     .capabilities   = CODEC_CAP_DR1,
00436     .long_name      = NULL_IF_CONFIG_SMALL("Musepack SV8"),
00437 };