libavcodec/mpc8.c

   1 /*
   2  * Musepack SV8 decoder
   3  * Copyright (c) 2007 Konstantin Shishkov
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 libavcodec/mpc8.c Musepack SV8 decoder
  24  * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
  25  * divided into 32 subbands.
  26  */
  27
  28 #include "libavutil/lfg.h"
  29 #include "avcodec.h"
  30 #include "get_bits.h"
  31 #include "dsputil.h"
  32 #include "mpegaudio.h"
  33
  34 #include "mpc.h"
  35 #include "mpcdata.h"
  36 #include "mpc8data.h"
  37 #include "mpc8huff.h"
  38
  39 static VLC band_vlc, scfi_vlc[2], dscf_vlc[2], res_vlc[2];
  40 static VLC q1_vlc, q2_vlc[2], q3_vlc[2], quant_vlc[4][2], q9up_vlc;
  41
  42 static const int q3_offsets[2] = { MPC8_Q3_OFFSET, MPC8_Q4_OFFSET };
  43 static const int quant_offsets[6] = { MPC8_Q5_OFFSET, MPC8_Q6_OFFSET, MPC8_Q7_OFFSET, MPC8_Q8_OFFSET };
  44
  45 static inline int mpc8_dec_base(GetBitContext *gb, int k, int n)
  46 {
  47     int code = get_bits(gb, mpc8_cnk_len[k-1][n-1] - 1);
  48
  49     if (code >= mpc8_cnk_lost[k-1][n-1])
  50         code = ((code << 1) | get_bits1(gb)) - mpc8_cnk_lost[k-1][n-1];
  51
  52     return code;
  53 }
  54
  55 static inline int mpc8_dec_enum(GetBitContext *gb, int k, int n)
  56 {
  57     int bits = 0;
  58     const uint32_t * C = mpc8_cnk[k-1];
  59     int code = mpc8_dec_base(gb, k, n);
  60
  61     do {
  62         n--;
  63         if (code >= C[n]) {
  64             bits |= 1 << n;
  65             code -= C[n];
  66             C -= 32;
  67             k--;
  68         }
  69     } while(k > 0);
  70
  71     return bits;
  72 }
  73
  74 static inline int mpc8_get_mod_golomb(GetBitContext *gb, int m)
  75 {
  76     if(mpc8_cnk_len[0][m] < 1) return 0;
  77     return mpc8_dec_base(gb, 1, m+1);
  78 }
  79
  80 static int mpc8_get_mask(GetBitContext *gb, int size, int t)
  81 {
  82     int mask = 0;
  83
  84     if(t && t != size)
  85          mask = mpc8_dec_enum(gb, FFMIN(t, size - t), size);
  86     if((t << 1) > size) mask = ~mask;
  87
  88     return mask;
  89 }
  90
  91 static const uint16_t vlc_offsets[13] = {
  92     0, 640, 1184, 1748, 2298, 2426, 2554, 3066, 3578, 4106, 4618, 5196, 5708
  93 };
  94
  95 static av_cold int mpc8_decode_init(AVCodecContext * avctx)
  96 {
  97     int i;
  98     MPCContext *c = avctx->priv_data;
  99     GetBitContext gb;
 100     static int vlc_initialized = 0;
 101
 102     static VLC_TYPE band_table[542][2];
 103     static VLC_TYPE q1_table[520][2];
 104     static VLC_TYPE q9up_table[524][2];
 105     static VLC_TYPE scfi0_table[1 << MPC8_SCFI0_BITS][2];
 106     static VLC_TYPE scfi1_table[1 << MPC8_SCFI1_BITS][2];
 107     static VLC_TYPE dscf0_table[560][2];
 108     static VLC_TYPE dscf1_table[598][2];
 109     static VLC_TYPE q3_0_table[512][2];
 110     static VLC_TYPE q3_1_table[516][2];
 111     static VLC_TYPE codes_table[5708][2];
 112
 113     if(avctx->extradata_size < 2){
 114         av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
 115         return -1;
 116     }
 117     memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
 118     av_lfg_init(&c->rnd, 0xDEADBEEF);
 119     dsputil_init(&c->dsp, avctx);
 120
 121     ff_mpc_init();
 122
 123     init_get_bits(&gb, avctx->extradata, 16);
 124
 125     skip_bits(&gb, 3);//sample rate
 126     c->maxbands = get_bits(&gb, 5) + 1;
 127     skip_bits(&gb, 4);//channels
 128     c->MSS = get_bits1(&gb);
 129     c->frames = 1 << (get_bits(&gb, 3) * 2);
 130
 131     if(vlc_initialized) return 0;
 132     av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
 133
 134     band_vlc.table = band_table;
 135     band_vlc.table_allocated = 542;
 136     init_vlc(&band_vlc, MPC8_BANDS_BITS, MPC8_BANDS_SIZE,
 137              mpc8_bands_bits,  1, 1,
 138              mpc8_bands_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 139
 140     q1_vlc.table = q1_table;
 141     q1_vlc.table_allocated = 520;
 142     init_vlc(&q1_vlc, MPC8_Q1_BITS, MPC8_Q1_SIZE,
 143              mpc8_q1_bits,  1, 1,
 144              mpc8_q1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 145     q9up_vlc.table = q9up_table;
 146     q9up_vlc.table_allocated = 524;
 147     init_vlc(&q9up_vlc, MPC8_Q9UP_BITS, MPC8_Q9UP_SIZE,
 148              mpc8_q9up_bits,  1, 1,
 149              mpc8_q9up_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 150
 151     scfi_vlc[0].table = scfi0_table;
 152     scfi_vlc[0].table_allocated = 1 << MPC8_SCFI0_BITS;
 153     init_vlc(&scfi_vlc[0], MPC8_SCFI0_BITS, MPC8_SCFI0_SIZE,
 154              mpc8_scfi0_bits,  1, 1,
 155              mpc8_scfi0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 156     scfi_vlc[1].table = scfi1_table;
 157     scfi_vlc[1].table_allocated = 1 << MPC8_SCFI1_BITS;
 158     init_vlc(&scfi_vlc[1], MPC8_SCFI1_BITS, MPC8_SCFI1_SIZE,
 159              mpc8_scfi1_bits,  1, 1,
 160              mpc8_scfi1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 161
 162     dscf_vlc[0].table = dscf0_table;
 163     dscf_vlc[0].table_allocated = 560;
 164     init_vlc(&dscf_vlc[0], MPC8_DSCF0_BITS, MPC8_DSCF0_SIZE,
 165              mpc8_dscf0_bits,  1, 1,
 166              mpc8_dscf0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 167     dscf_vlc[1].table = dscf1_table;
 168     dscf_vlc[1].table_allocated = 598;
 169     init_vlc(&dscf_vlc[1], MPC8_DSCF1_BITS, MPC8_DSCF1_SIZE,
 170              mpc8_dscf1_bits,  1, 1,
 171              mpc8_dscf1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 172
 173     q3_vlc[0].table = q3_0_table;
 174     q3_vlc[0].table_allocated = 512;
 175     init_vlc_sparse(&q3_vlc[0], MPC8_Q3_BITS, MPC8_Q3_SIZE,
 176              mpc8_q3_bits,  1, 1,
 177              mpc8_q3_codes, 1, 1,
 178              mpc8_q3_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
 179     q3_vlc[1].table = q3_1_table;
 180     q3_vlc[1].table_allocated = 516;
 181     init_vlc_sparse(&q3_vlc[1], MPC8_Q4_BITS, MPC8_Q4_SIZE,
 182              mpc8_q4_bits,  1, 1,
 183              mpc8_q4_codes, 1, 1,
 184              mpc8_q4_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
 185
 186     for(i = 0; i < 2; i++){
 187         res_vlc[i].table = &codes_table[vlc_offsets[0+i]];
 188         res_vlc[i].table_allocated = vlc_offsets[1+i] - vlc_offsets[0+i];
 189         init_vlc(&res_vlc[i], MPC8_RES_BITS, MPC8_RES_SIZE,
 190                  &mpc8_res_bits[i],  1, 1,
 191                  &mpc8_res_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 192
 193         q2_vlc[i].table = &codes_table[vlc_offsets[2+i]];
 194         q2_vlc[i].table_allocated = vlc_offsets[3+i] - vlc_offsets[2+i];
 195         init_vlc(&q2_vlc[i], MPC8_Q2_BITS, MPC8_Q2_SIZE,
 196                  &mpc8_q2_bits[i],  1, 1,
 197                  &mpc8_q2_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 198
 199         quant_vlc[0][i].table = &codes_table[vlc_offsets[4+i]];
 200         quant_vlc[0][i].table_allocated = vlc_offsets[5+i] - vlc_offsets[4+i];
 201         init_vlc(&quant_vlc[0][i], MPC8_Q5_BITS, MPC8_Q5_SIZE,
 202                  &mpc8_q5_bits[i],  1, 1,
 203                  &mpc8_q5_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 204         quant_vlc[1][i].table = &codes_table[vlc_offsets[6+i]];
 205         quant_vlc[1][i].table_allocated = vlc_offsets[7+i] - vlc_offsets[6+i];
 206         init_vlc(&quant_vlc[1][i], MPC8_Q6_BITS, MPC8_Q6_SIZE,
 207                  &mpc8_q6_bits[i],  1, 1,
 208                  &mpc8_q6_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 209         quant_vlc[2][i].table = &codes_table[vlc_offsets[8+i]];
 210         quant_vlc[2][i].table_allocated = vlc_offsets[9+i] - vlc_offsets[8+i];
 211         init_vlc(&quant_vlc[2][i], MPC8_Q7_BITS, MPC8_Q7_SIZE,
 212                  &mpc8_q7_bits[i],  1, 1,
 213                  &mpc8_q7_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 214         quant_vlc[3][i].table = &codes_table[vlc_offsets[10+i]];
 215         quant_vlc[3][i].table_allocated = vlc_offsets[11+i] - vlc_offsets[10+i];
 216         init_vlc(&quant_vlc[3][i], MPC8_Q8_BITS, MPC8_Q8_SIZE,
 217                  &mpc8_q8_bits[i],  1, 1,
 218                  &mpc8_q8_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 219     }
 220     vlc_initialized = 1;
 221     avctx->sample_fmt = SAMPLE_FMT_S16;
 222     avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
 223     return 0;
 224 }
 225
 226 static int mpc8_decode_frame(AVCodecContext * avctx,
 227                             void *data, int *data_size,
 228                             AVPacket *avpkt)
 229 {
 230     const uint8_t *buf = avpkt->data;
 231     int buf_size = avpkt->size;
 232     MPCContext *c = avctx->priv_data;
 233     GetBitContext gb2, *gb = &gb2;
 234     int i, j, k, ch, cnt, res, t;
 235     Band *bands = c->bands;
 236     int off;
 237     int maxband, keyframe;
 238     int last[2];
 239
 240     keyframe = c->cur_frame == 0;
 241
 242     if(keyframe){
 243         memset(c->Q, 0, sizeof(c->Q));
 244         c->last_bits_used = 0;
 245     }
 246     init_get_bits(gb, buf, buf_size * 8);
 247     skip_bits(gb, c->last_bits_used & 7);
 248
 249     if(keyframe)
 250         maxband = mpc8_get_mod_golomb(gb, c->maxbands + 1);
 251     else{
 252         maxband = c->last_max_band + get_vlc2(gb, band_vlc.table, MPC8_BANDS_BITS, 2);
 253         if(maxband > 32) maxband -= 33;
 254     }
 255     c->last_max_band = maxband;
 256
 257     /* read subband indexes */
 258     if(maxband){
 259         last[0] = last[1] = 0;
 260         for(i = maxband - 1; i >= 0; i--){
 261             for(ch = 0; ch < 2; ch++){
 262                 last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
 263                 if(last[ch] > 15) last[ch] -= 17;
 264                 bands[i].res[ch] = last[ch];
 265             }
 266         }
 267         if(c->MSS){
 268             int mask;
 269
 270             cnt = 0;
 271             for(i = 0; i < maxband; i++)
 272                 if(bands[i].res[0] || bands[i].res[1])
 273                     cnt++;
 274             t = mpc8_get_mod_golomb(gb, cnt);
 275             mask = mpc8_get_mask(gb, cnt, t);
 276             for(i = maxband - 1; i >= 0; i--)
 277                 if(bands[i].res[0] || bands[i].res[1]){
 278                     bands[i].msf = mask & 1;
 279                     mask >>= 1;
 280                 }
 281         }
 282     }
 283     for(i = maxband; i < c->maxbands; i++)
 284         bands[i].res[0] = bands[i].res[1] = 0;
 285
 286     if(keyframe){
 287         for(i = 0; i < 32; i++)
 288             c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
 289     }
 290
 291     for(i = 0; i < maxband; i++){
 292         if(bands[i].res[0] || bands[i].res[1]){
 293             cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
 294             if(cnt >= 0){
 295                 t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
 296                 if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
 297                 if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
 298             }
 299         }
 300     }
 301
 302     for(i = 0; i < maxband; i++){
 303         for(ch = 0; ch < 2; ch++){
 304             if(!bands[i].res[ch]) continue;
 305
 306             if(c->oldDSCF[ch][i]){
 307                 bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
 308                 c->oldDSCF[ch][i] = 0;
 309             }else{
 310                 t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
 311                 if(t == 64)
 312                     t += get_bits(gb, 6);
 313                 bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
 314             }
 315             for(j = 0; j < 2; j++){
 316                 if((bands[i].scfi[ch] << j) & 2)
 317                     bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
 318                 else{
 319                     t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
 320                     if(t == 31)
 321                         t = 64 + get_bits(gb, 6);
 322                     bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
 323                 }
 324             }
 325         }
 326     }
 327
 328     for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
 329         for(ch = 0; ch < 2; ch++){
 330             res = bands[i].res[ch];
 331             switch(res){
 332             case -1:
 333                 for(j = 0; j < SAMPLES_PER_BAND; j++)
 334                     c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
 335                 break;
 336             case 0:
 337                 break;
 338             case 1:
 339                 for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
 340                     cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
 341                     t = mpc8_get_mask(gb, 18, cnt);
 342                     for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
 343                         c->Q[ch][off + j + k] = (t & 0x20000) ? (get_bits1(gb) << 1) - 1 : 0;
 344                 }
 345                 break;
 346             case 2:
 347                 cnt = 6;//2*mpc8_thres[res]
 348                 for(j = 0; j < SAMPLES_PER_BAND; j += 3){
 349                     t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
 350                     c->Q[ch][off + j + 0] = mpc8_idx50[t];
 351                     c->Q[ch][off + j + 1] = mpc8_idx51[t];
 352                     c->Q[ch][off + j + 2] = mpc8_idx52[t];
 353                     cnt = (cnt >> 1) + mpc8_huffq2[t];
 354                 }
 355                 break;
 356             case 3:
 357             case 4:
 358                 for(j = 0; j < SAMPLES_PER_BAND; j += 2){
 359                     t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
 360                     c->Q[ch][off + j + 1] = t >> 4;
 361                     c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
 362                 }
 363                 break;
 364             case 5:
 365             case 6:
 366             case 7:
 367             case 8:
 368                 cnt = 2 * mpc8_thres[res];
 369                 for(j = 0; j < SAMPLES_PER_BAND; j++){
 370                     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];
 371                     c->Q[ch][off + j] = t;
 372                     cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
 373                 }
 374                 break;
 375             default:
 376                 for(j = 0; j < SAMPLES_PER_BAND; j++){
 377                     c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
 378                     if(res != 9){
 379                         c->Q[ch][off + j] <<= res - 9;
 380                         c->Q[ch][off + j] |= get_bits(gb, res - 9);
 381                     }
 382                     c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
 383                 }
 384             }
 385         }
 386     }
 387
 388     ff_mpc_dequantize_and_synth(c, maxband, data);
 389
 390     c->cur_frame++;
 391
 392     c->last_bits_used = get_bits_count(gb);
 393     if(c->cur_frame >= c->frames)
 394         c->cur_frame = 0;
 395     *data_size =  MPC_FRAME_SIZE * 4;
 396
 397     return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
 398 }
 399
 400 AVCodec mpc8_decoder = {
 401     "mpc8",
 402     CODEC_TYPE_AUDIO,
 403     CODEC_ID_MUSEPACK8,
 404     sizeof(MPCContext),
 405     mpc8_decode_init,
 406     NULL,
 407     NULL,
 408     mpc8_decode_frame,
 409     .long_name = NULL_IF_CONFIG_SMALL("Musepack SV8"),
 410 };