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libavcodec/mpc8.c

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

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