libavcodec/mpc8.c

   1 /*
   2  * Musepack SV8 decoder
   3  * Copyright (c) 2007 Konstantin Shishkov
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * Libav is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with Libav; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file
  24  * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
  25  * divided into 32 subbands.
  26  */
  27
  28 #include "libavutil/channel_layout.h"
  29 #include "libavutil/lfg.h"
  30
  31 #include "avcodec.h"
  32 #include "bitstream.h"
  33 #include "internal.h"
  34 #include "mpegaudiodsp.h"
  35 #include "vlc.h"
  36
  37 #include "mpc.h"
  38 #include "mpc8data.h"
  39 #include "mpc8huff.h"
  40
  41 static VLC band_vlc, scfi_vlc[2], dscf_vlc[2], res_vlc[2];
  42 static VLC q1_vlc, q2_vlc[2], q3_vlc[2], quant_vlc[4][2], q9up_vlc;
  43
  44 static const int q3_offsets[2] = { MPC8_Q3_OFFSET, MPC8_Q4_OFFSET };
  45 static const int quant_offsets[6] = { MPC8_Q5_OFFSET, MPC8_Q6_OFFSET, MPC8_Q7_OFFSET, MPC8_Q8_OFFSET };
  46
  47 static inline int mpc8_dec_base(BitstreamContext *bc, int k, int n)
  48 {
  49     int len = mpc8_cnk_len[k-1][n-1] - 1;
  50     int code = len ? bitstream_read(bc, len) : 0;
  51
  52     if (code >= mpc8_cnk_lost[k-1][n-1])
  53         code = ((code << 1) | bitstream_read_bit(bc)) - mpc8_cnk_lost[k - 1][n - 1];
  54
  55     return code;
  56 }
  57
  58 static inline int mpc8_dec_enum(BitstreamContext *bc, int k, int n)
  59 {
  60     int bits = 0;
  61     const uint32_t * C = mpc8_cnk[k-1];
  62     int code = mpc8_dec_base(bc, k, n);
  63
  64     do {
  65         n--;
  66         if (code >= C[n]) {
  67             bits |= 1 << n;
  68             code -= C[n];
  69             C -= 32;
  70             k--;
  71         }
  72     } while(k > 0);
  73
  74     return bits;
  75 }
  76
  77 static inline int mpc8_get_mod_golomb(BitstreamContext *bc, int m)
  78 {
  79     if(mpc8_cnk_len[0][m] < 1) return 0;
  80     return mpc8_dec_base(bc, 1, m + 1);
  81 }
  82
  83 static int mpc8_get_mask(BitstreamContext *bc, int size, int t)
  84 {
  85     int mask = 0;
  86
  87     if(t && t != size)
  88          mask = mpc8_dec_enum(bc, FFMIN(t, size - t), size);
  89     if((t << 1) > size) mask = ~mask;
  90
  91     return mask;
  92 }
  93
  94 static const uint16_t vlc_offsets[13] = {
  95     0, 640, 1184, 1748, 2298, 2426, 2554, 3066, 3578, 4106, 4618, 5196, 5708
  96 };
  97
  98 static av_cold int mpc8_decode_init(AVCodecContext * avctx)
  99 {
 100     int i;
 101     MPCContext *c = avctx->priv_data;
 102     BitstreamContext bc;
 103     static int vlc_initialized = 0;
 104     int channels;
 105
 106     static VLC_TYPE band_table[542][2];
 107     static VLC_TYPE q1_table[520][2];
 108     static VLC_TYPE q9up_table[524][2];
 109     static VLC_TYPE scfi0_table[1 << MPC8_SCFI0_BITS][2];
 110     static VLC_TYPE scfi1_table[1 << MPC8_SCFI1_BITS][2];
 111     static VLC_TYPE dscf0_table[560][2];
 112     static VLC_TYPE dscf1_table[598][2];
 113     static VLC_TYPE q3_0_table[512][2];
 114     static VLC_TYPE q3_1_table[516][2];
 115     static VLC_TYPE codes_table[5708][2];
 116
 117     if(avctx->extradata_size < 2){
 118         av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
 119         return -1;
 120     }
 121     memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
 122     av_lfg_init(&c->rnd, 0xDEADBEEF);
 123     ff_mpadsp_init(&c->mpadsp);
 124
 125     ff_mpc_init();
 126
 127     bitstream_init(&bc, avctx->extradata, 16);
 128
 129     bitstream_skip(&bc, 3); // sample rate
 130     c->maxbands = bitstream_read(&bc, 5) + 1;
 131     channels    = bitstream_read(&bc, 4) + 1;
 132     if (channels > 2) {
 133         avpriv_request_sample(avctx, "Multichannel MPC SV8");
 134         return AVERROR_PATCHWELCOME;
 135     }
 136     c->MSS    = bitstream_read_bit(&bc);
 137     c->frames = 1 << (bitstream_read(&bc, 3) * 2);
 138
 139     avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
 140     avctx->channel_layout = (avctx->channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
 141
 142     if(vlc_initialized) return 0;
 143     av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
 144
 145     band_vlc.table = band_table;
 146     band_vlc.table_allocated = 542;
 147     init_vlc(&band_vlc, MPC8_BANDS_BITS, MPC8_BANDS_SIZE,
 148              mpc8_bands_bits,  1, 1,
 149              mpc8_bands_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 150
 151     q1_vlc.table = q1_table;
 152     q1_vlc.table_allocated = 520;
 153     init_vlc(&q1_vlc, MPC8_Q1_BITS, MPC8_Q1_SIZE,
 154              mpc8_q1_bits,  1, 1,
 155              mpc8_q1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 156     q9up_vlc.table = q9up_table;
 157     q9up_vlc.table_allocated = 524;
 158     init_vlc(&q9up_vlc, MPC8_Q9UP_BITS, MPC8_Q9UP_SIZE,
 159              mpc8_q9up_bits,  1, 1,
 160              mpc8_q9up_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 161
 162     scfi_vlc[0].table = scfi0_table;
 163     scfi_vlc[0].table_allocated = 1 << MPC8_SCFI0_BITS;
 164     init_vlc(&scfi_vlc[0], MPC8_SCFI0_BITS, MPC8_SCFI0_SIZE,
 165              mpc8_scfi0_bits,  1, 1,
 166              mpc8_scfi0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 167     scfi_vlc[1].table = scfi1_table;
 168     scfi_vlc[1].table_allocated = 1 << MPC8_SCFI1_BITS;
 169     init_vlc(&scfi_vlc[1], MPC8_SCFI1_BITS, MPC8_SCFI1_SIZE,
 170              mpc8_scfi1_bits,  1, 1,
 171              mpc8_scfi1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 172
 173     dscf_vlc[0].table = dscf0_table;
 174     dscf_vlc[0].table_allocated = 560;
 175     init_vlc(&dscf_vlc[0], MPC8_DSCF0_BITS, MPC8_DSCF0_SIZE,
 176              mpc8_dscf0_bits,  1, 1,
 177              mpc8_dscf0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 178     dscf_vlc[1].table = dscf1_table;
 179     dscf_vlc[1].table_allocated = 598;
 180     init_vlc(&dscf_vlc[1], MPC8_DSCF1_BITS, MPC8_DSCF1_SIZE,
 181              mpc8_dscf1_bits,  1, 1,
 182              mpc8_dscf1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 183
 184     q3_vlc[0].table = q3_0_table;
 185     q3_vlc[0].table_allocated = 512;
 186     ff_init_vlc_sparse(&q3_vlc[0], MPC8_Q3_BITS, MPC8_Q3_SIZE,
 187              mpc8_q3_bits,  1, 1,
 188              mpc8_q3_codes, 1, 1,
 189              mpc8_q3_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
 190     q3_vlc[1].table = q3_1_table;
 191     q3_vlc[1].table_allocated = 516;
 192     ff_init_vlc_sparse(&q3_vlc[1], MPC8_Q4_BITS, MPC8_Q4_SIZE,
 193              mpc8_q4_bits,  1, 1,
 194              mpc8_q4_codes, 1, 1,
 195              mpc8_q4_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
 196
 197     for(i = 0; i < 2; i++){
 198         res_vlc[i].table = &codes_table[vlc_offsets[0+i]];
 199         res_vlc[i].table_allocated = vlc_offsets[1+i] - vlc_offsets[0+i];
 200         init_vlc(&res_vlc[i], MPC8_RES_BITS, MPC8_RES_SIZE,
 201                  &mpc8_res_bits[i],  1, 1,
 202                  &mpc8_res_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 203
 204         q2_vlc[i].table = &codes_table[vlc_offsets[2+i]];
 205         q2_vlc[i].table_allocated = vlc_offsets[3+i] - vlc_offsets[2+i];
 206         init_vlc(&q2_vlc[i], MPC8_Q2_BITS, MPC8_Q2_SIZE,
 207                  &mpc8_q2_bits[i],  1, 1,
 208                  &mpc8_q2_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 209
 210         quant_vlc[0][i].table = &codes_table[vlc_offsets[4+i]];
 211         quant_vlc[0][i].table_allocated = vlc_offsets[5+i] - vlc_offsets[4+i];
 212         init_vlc(&quant_vlc[0][i], MPC8_Q5_BITS, MPC8_Q5_SIZE,
 213                  &mpc8_q5_bits[i],  1, 1,
 214                  &mpc8_q5_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 215         quant_vlc[1][i].table = &codes_table[vlc_offsets[6+i]];
 216         quant_vlc[1][i].table_allocated = vlc_offsets[7+i] - vlc_offsets[6+i];
 217         init_vlc(&quant_vlc[1][i], MPC8_Q6_BITS, MPC8_Q6_SIZE,
 218                  &mpc8_q6_bits[i],  1, 1,
 219                  &mpc8_q6_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 220         quant_vlc[2][i].table = &codes_table[vlc_offsets[8+i]];
 221         quant_vlc[2][i].table_allocated = vlc_offsets[9+i] - vlc_offsets[8+i];
 222         init_vlc(&quant_vlc[2][i], MPC8_Q7_BITS, MPC8_Q7_SIZE,
 223                  &mpc8_q7_bits[i],  1, 1,
 224                  &mpc8_q7_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 225         quant_vlc[3][i].table = &codes_table[vlc_offsets[10+i]];
 226         quant_vlc[3][i].table_allocated = vlc_offsets[11+i] - vlc_offsets[10+i];
 227         init_vlc(&quant_vlc[3][i], MPC8_Q8_BITS, MPC8_Q8_SIZE,
 228                  &mpc8_q8_bits[i],  1, 1,
 229                  &mpc8_q8_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 230     }
 231     vlc_initialized = 1;
 232
 233     return 0;
 234 }
 235
 236 static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
 237                              int *got_frame_ptr, AVPacket *avpkt)
 238 {
 239     AVFrame *frame     = data;
 240     const uint8_t *buf = avpkt->data;
 241     int buf_size = avpkt->size;
 242     MPCContext *c = avctx->priv_data;
 243     BitstreamContext bc2, *bc = &bc2;
 244     int i, j, k, ch, cnt, res, t;
 245     Band *bands = c->bands;
 246     int off;
 247     int maxband, keyframe;
 248     int last[2];
 249
 250     /* get output buffer */
 251     frame->nb_samples = MPC_FRAME_SIZE;
 252     if ((res = ff_get_buffer(avctx, frame, 0)) < 0) {
 253         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 254         return res;
 255     }
 256
 257     keyframe = c->cur_frame == 0;
 258
 259     if(keyframe){
 260         memset(c->Q, 0, sizeof(c->Q));
 261         c->last_bits_used = 0;
 262     }
 263     bitstream_init8(bc, buf, buf_size);
 264     bitstream_skip(bc, c->last_bits_used & 7);
 265
 266     if(keyframe)
 267         maxband = mpc8_get_mod_golomb(bc, c->maxbands + 1);
 268     else{
 269         maxband = c->last_max_band + bitstream_read_vlc(bc, band_vlc.table, MPC8_BANDS_BITS, 2);
 270         if(maxband > 32) maxband -= 33;
 271     }
 272     if(maxband > c->maxbands + 1)
 273         return AVERROR_INVALIDDATA;
 274     c->last_max_band = maxband;
 275
 276     /* read subband indexes */
 277     if(maxband){
 278         last[0] = last[1] = 0;
 279         for(i = maxband - 1; i >= 0; i--){
 280             for(ch = 0; ch < 2; ch++){
 281                 last[ch] = bitstream_read_vlc(bc, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
 282                 if(last[ch] > 15) last[ch] -= 17;
 283                 bands[i].res[ch] = last[ch];
 284             }
 285         }
 286         if(c->MSS){
 287             int mask;
 288
 289             cnt = 0;
 290             for(i = 0; i < maxband; i++)
 291                 if(bands[i].res[0] || bands[i].res[1])
 292                     cnt++;
 293             t = mpc8_get_mod_golomb(bc, cnt);
 294             mask = mpc8_get_mask(bc, cnt, t);
 295             for(i = maxband - 1; i >= 0; i--)
 296                 if(bands[i].res[0] || bands[i].res[1]){
 297                     bands[i].msf = mask & 1;
 298                     mask >>= 1;
 299                 }
 300         }
 301     }
 302     for(i = maxband; i < c->maxbands; i++)
 303         bands[i].res[0] = bands[i].res[1] = 0;
 304
 305     if(keyframe){
 306         for(i = 0; i < 32; i++)
 307             c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
 308     }
 309
 310     for(i = 0; i < maxband; i++){
 311         if(bands[i].res[0] || bands[i].res[1]){
 312             cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
 313             if(cnt >= 0){
 314                 t = bitstream_read_vlc(bc, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
 315                 if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
 316                 if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
 317             }
 318         }
 319     }
 320
 321     for(i = 0; i < maxband; i++){
 322         for(ch = 0; ch < 2; ch++){
 323             if(!bands[i].res[ch]) continue;
 324
 325             if(c->oldDSCF[ch][i]){
 326                 bands[i].scf_idx[ch][0] = bitstream_read(bc, 7) - 6;
 327                 c->oldDSCF[ch][i] = 0;
 328             }else{
 329                 t = bitstream_read_vlc(bc, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
 330                 if(t == 64)
 331                     t += bitstream_read(bc, 6);
 332                 bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
 333             }
 334             for(j = 0; j < 2; j++){
 335                 if((bands[i].scfi[ch] << j) & 2)
 336                     bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
 337                 else{
 338                     t = bitstream_read_vlc(bc, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
 339                     if(t == 31)
 340                         t = 64 + bitstream_read(bc, 6);
 341                     bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
 342                 }
 343             }
 344         }
 345     }
 346
 347     for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
 348         for(ch = 0; ch < 2; ch++){
 349             res = bands[i].res[ch];
 350             switch(res){
 351             case -1:
 352                 for(j = 0; j < SAMPLES_PER_BAND; j++)
 353                     c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
 354                 break;
 355             case 0:
 356                 break;
 357             case 1:
 358                 for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
 359                     cnt = bitstream_read_vlc(bc, q1_vlc.table, MPC8_Q1_BITS, 2);
 360                     t = mpc8_get_mask(bc, 18, cnt);
 361                     for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
 362                         c->Q[ch][off + j + k] = (t & 0x20000) ? (bitstream_read_bit(bc) << 1) - 1 : 0;
 363                 }
 364                 break;
 365             case 2:
 366                 cnt = 6;//2*mpc8_thres[res]
 367                 for(j = 0; j < SAMPLES_PER_BAND; j += 3){
 368                     t = bitstream_read_vlc(bc, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
 369                     c->Q[ch][off + j + 0] = mpc8_idx50[t];
 370                     c->Q[ch][off + j + 1] = mpc8_idx51[t];
 371                     c->Q[ch][off + j + 2] = mpc8_idx52[t];
 372                     cnt = (cnt >> 1) + mpc8_huffq2[t];
 373                 }
 374                 break;
 375             case 3:
 376             case 4:
 377                 for(j = 0; j < SAMPLES_PER_BAND; j += 2){
 378                     t = bitstream_read_vlc(bc, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
 379                     c->Q[ch][off + j + 1] = t >> 4;
 380                     c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
 381                 }
 382                 break;
 383             case 5:
 384             case 6:
 385             case 7:
 386             case 8:
 387                 cnt = 2 * mpc8_thres[res];
 388                 for(j = 0; j < SAMPLES_PER_BAND; j++){
 389                     t = bitstream_read_vlc(bc, quant_vlc[res - 5][cnt > mpc8_thres[res]].table, quant_vlc[res - 5][cnt > mpc8_thres[res]].bits, 2) + quant_offsets[res - 5];
 390                     c->Q[ch][off + j] = t;
 391                     cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
 392                 }
 393                 break;
 394             default:
 395                 for(j = 0; j < SAMPLES_PER_BAND; j++){
 396                     c->Q[ch][off + j] = bitstream_read_vlc(bc, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
 397                     if(res != 9){
 398                         c->Q[ch][off + j] <<= res - 9;
 399                         c->Q[ch][off + j] |= bitstream_read(bc, res - 9);
 400                     }
 401                     c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
 402                 }
 403             }
 404         }
 405     }
 406
 407     ff_mpc_dequantize_and_synth(c, maxband - 1,
 408                                 (int16_t **)frame->extended_data,
 409                                 avctx->channels);
 410
 411     c->cur_frame++;
 412
 413     c->last_bits_used = bitstream_tell(bc);
 414     if (bitstream_bits_left(bc) < 8) // we have only padding left
 415         c->last_bits_used = buf_size << 3;
 416     if(c->cur_frame >= c->frames)
 417         c->cur_frame = 0;
 418
 419     *got_frame_ptr = 1;
 420
 421     return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
 422 }
 423
 424 static av_cold void mpc8_decode_flush(AVCodecContext *avctx)
 425 {
 426     MPCContext *c = avctx->priv_data;
 427     c->cur_frame = 0;
 428 }
 429
 430 AVCodec ff_mpc8_decoder = {
 431     .name           = "mpc8",
 432     .long_name      = NULL_IF_CONFIG_SMALL("Musepack SV8"),
 433     .type           = AVMEDIA_TYPE_AUDIO,
 434     .id             = AV_CODEC_ID_MUSEPACK8,
 435     .priv_data_size = sizeof(MPCContext),
 436     .init           = mpc8_decode_init,
 437     .decode         = mpc8_decode_frame,
 438     .flush          = mpc8_decode_flush,
 439     .capabilities   = AV_CODEC_CAP_DR1,
 440     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
 441                                                       AV_SAMPLE_FMT_NONE },
 442 };