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 len = mpc8_cnk_len[k-1][n-1] - 1;
  48     int code = len ? get_bits_long(gb, len) : 0;
  49
  50     if (code >= mpc8_cnk_lost[k-1][n-1])
  51         code = ((code << 1) | get_bits1(gb)) - mpc8_cnk_lost[k-1][n-1];
  52
  53     return code;
  54 }
  55
  56 static inline int mpc8_dec_enum(GetBitContext *gb, int k, int n)
  57 {
  58     int bits = 0;
  59     const uint32_t * C = mpc8_cnk[k-1];
  60     int code = mpc8_dec_base(gb, k, n);
  61
  62     do {
  63         n--;
  64         if (code >= C[n]) {
  65             bits |= 1 << n;
  66             code -= C[n];
  67             C -= 32;
  68             k--;
  69         }
  70     } while(k > 0);
  71
  72     return bits;
  73 }
  74
  75 static inline int mpc8_get_mod_golomb(GetBitContext *gb, int m)
  76 {
  77     if(mpc8_cnk_len[0][m] < 1) return 0;
  78     return mpc8_dec_base(gb, 1, m+1);
  79 }
  80
  81 static int mpc8_get_mask(GetBitContext *gb, int size, int t)
  82 {
  83     int mask = 0;
  84
  85     if(t && t != size)
  86          mask = mpc8_dec_enum(gb, FFMIN(t, size - t), size);
  87     if((t << 1) > size) mask = ~mask;
  88
  89     return mask;
  90 }
  91
  92 static const uint16_t vlc_offsets[13] = {
  93     0, 640, 1184, 1748, 2298, 2426, 2554, 3066, 3578, 4106, 4618, 5196, 5708
  94 };
  95
  96 static av_cold int mpc8_decode_init(AVCodecContext * avctx)
  97 {
  98     int i;
  99     MPCContext *c = avctx->priv_data;
 100     GetBitContext gb;
 101     static int vlc_initialized = 0;
 102
 103     static VLC_TYPE band_table[542][2];
 104     static VLC_TYPE q1_table[520][2];
 105     static VLC_TYPE q9up_table[524][2];
 106     static VLC_TYPE scfi0_table[1 << MPC8_SCFI0_BITS][2];
 107     static VLC_TYPE scfi1_table[1 << MPC8_SCFI1_BITS][2];
 108     static VLC_TYPE dscf0_table[560][2];
 109     static VLC_TYPE dscf1_table[598][2];
 110     static VLC_TYPE q3_0_table[512][2];
 111     static VLC_TYPE q3_1_table[516][2];
 112     static VLC_TYPE codes_table[5708][2];
 113
 114     if(avctx->extradata_size < 2){
 115         av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
 116         return -1;
 117     }
 118     memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
 119     av_lfg_init(&c->rnd, 0xDEADBEEF);
 120     dsputil_init(&c->dsp, avctx);
 121
 122     ff_mpc_init();
 123
 124     init_get_bits(&gb, avctx->extradata, 16);
 125
 126     skip_bits(&gb, 3);//sample rate
 127     c->maxbands = get_bits(&gb, 5) + 1;
 128     skip_bits(&gb, 4);//channels
 129     c->MSS = get_bits1(&gb);
 130     c->frames = 1 << (get_bits(&gb, 3) * 2);
 131
 132     if(vlc_initialized) return 0;
 133     av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
 134
 135     band_vlc.table = band_table;
 136     band_vlc.table_allocated = 542;
 137     init_vlc(&band_vlc, MPC8_BANDS_BITS, MPC8_BANDS_SIZE,
 138              mpc8_bands_bits,  1, 1,
 139              mpc8_bands_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 140
 141     q1_vlc.table = q1_table;
 142     q1_vlc.table_allocated = 520;
 143     init_vlc(&q1_vlc, MPC8_Q1_BITS, MPC8_Q1_SIZE,
 144              mpc8_q1_bits,  1, 1,
 145              mpc8_q1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 146     q9up_vlc.table = q9up_table;
 147     q9up_vlc.table_allocated = 524;
 148     init_vlc(&q9up_vlc, MPC8_Q9UP_BITS, MPC8_Q9UP_SIZE,
 149              mpc8_q9up_bits,  1, 1,
 150              mpc8_q9up_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 151
 152     scfi_vlc[0].table = scfi0_table;
 153     scfi_vlc[0].table_allocated = 1 << MPC8_SCFI0_BITS;
 154     init_vlc(&scfi_vlc[0], MPC8_SCFI0_BITS, MPC8_SCFI0_SIZE,
 155              mpc8_scfi0_bits,  1, 1,
 156              mpc8_scfi0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 157     scfi_vlc[1].table = scfi1_table;
 158     scfi_vlc[1].table_allocated = 1 << MPC8_SCFI1_BITS;
 159     init_vlc(&scfi_vlc[1], MPC8_SCFI1_BITS, MPC8_SCFI1_SIZE,
 160              mpc8_scfi1_bits,  1, 1,
 161              mpc8_scfi1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 162
 163     dscf_vlc[0].table = dscf0_table;
 164     dscf_vlc[0].table_allocated = 560;
 165     init_vlc(&dscf_vlc[0], MPC8_DSCF0_BITS, MPC8_DSCF0_SIZE,
 166              mpc8_dscf0_bits,  1, 1,
 167              mpc8_dscf0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 168     dscf_vlc[1].table = dscf1_table;
 169     dscf_vlc[1].table_allocated = 598;
 170     init_vlc(&dscf_vlc[1], MPC8_DSCF1_BITS, MPC8_DSCF1_SIZE,
 171              mpc8_dscf1_bits,  1, 1,
 172              mpc8_dscf1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
 173
 174     q3_vlc[0].table = q3_0_table;
 175     q3_vlc[0].table_allocated = 512;
 176     init_vlc_sparse(&q3_vlc[0], MPC8_Q3_BITS, MPC8_Q3_SIZE,
 177              mpc8_q3_bits,  1, 1,
 178              mpc8_q3_codes, 1, 1,
 179              mpc8_q3_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
 180     q3_vlc[1].table = q3_1_table;
 181     q3_vlc[1].table_allocated = 516;
 182     init_vlc_sparse(&q3_vlc[1], MPC8_Q4_BITS, MPC8_Q4_SIZE,
 183              mpc8_q4_bits,  1, 1,
 184              mpc8_q4_codes, 1, 1,
 185              mpc8_q4_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
 186
 187     for(i = 0; i < 2; i++){
 188         res_vlc[i].table = &codes_table[vlc_offsets[0+i]];
 189         res_vlc[i].table_allocated = vlc_offsets[1+i] - vlc_offsets[0+i];
 190         init_vlc(&res_vlc[i], MPC8_RES_BITS, MPC8_RES_SIZE,
 191                  &mpc8_res_bits[i],  1, 1,
 192                  &mpc8_res_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 193
 194         q2_vlc[i].table = &codes_table[vlc_offsets[2+i]];
 195         q2_vlc[i].table_allocated = vlc_offsets[3+i] - vlc_offsets[2+i];
 196         init_vlc(&q2_vlc[i], MPC8_Q2_BITS, MPC8_Q2_SIZE,
 197                  &mpc8_q2_bits[i],  1, 1,
 198                  &mpc8_q2_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 199
 200         quant_vlc[0][i].table = &codes_table[vlc_offsets[4+i]];
 201         quant_vlc[0][i].table_allocated = vlc_offsets[5+i] - vlc_offsets[4+i];
 202         init_vlc(&quant_vlc[0][i], MPC8_Q5_BITS, MPC8_Q5_SIZE,
 203                  &mpc8_q5_bits[i],  1, 1,
 204                  &mpc8_q5_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 205         quant_vlc[1][i].table = &codes_table[vlc_offsets[6+i]];
 206         quant_vlc[1][i].table_allocated = vlc_offsets[7+i] - vlc_offsets[6+i];
 207         init_vlc(&quant_vlc[1][i], MPC8_Q6_BITS, MPC8_Q6_SIZE,
 208                  &mpc8_q6_bits[i],  1, 1,
 209                  &mpc8_q6_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 210         quant_vlc[2][i].table = &codes_table[vlc_offsets[8+i]];
 211         quant_vlc[2][i].table_allocated = vlc_offsets[9+i] - vlc_offsets[8+i];
 212         init_vlc(&quant_vlc[2][i], MPC8_Q7_BITS, MPC8_Q7_SIZE,
 213                  &mpc8_q7_bits[i],  1, 1,
 214                  &mpc8_q7_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 215         quant_vlc[3][i].table = &codes_table[vlc_offsets[10+i]];
 216         quant_vlc[3][i].table_allocated = vlc_offsets[11+i] - vlc_offsets[10+i];
 217         init_vlc(&quant_vlc[3][i], MPC8_Q8_BITS, MPC8_Q8_SIZE,
 218                  &mpc8_q8_bits[i],  1, 1,
 219                  &mpc8_q8_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
 220     }
 221     vlc_initialized = 1;
 222     avctx->sample_fmt = SAMPLE_FMT_S16;
 223     avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
 224     return 0;
 225 }
 226
 227 static int mpc8_decode_frame(AVCodecContext * avctx,
 228                             void *data, int *data_size,
 229                             AVPacket *avpkt)
 230 {
 231     const uint8_t *buf = avpkt->data;
 232     int buf_size = avpkt->size;
 233     MPCContext *c = avctx->priv_data;
 234     GetBitContext gb2, *gb = &gb2;
 235     int i, j, k, ch, cnt, res, t;
 236     Band *bands = c->bands;
 237     int off;
 238     int maxband, keyframe;
 239     int last[2];
 240
 241     keyframe = c->cur_frame == 0;
 242
 243     if(keyframe){
 244         memset(c->Q, 0, sizeof(c->Q));
 245         c->last_bits_used = 0;
 246     }
 247     init_get_bits(gb, buf, buf_size * 8);
 248     skip_bits(gb, c->last_bits_used & 7);
 249
 250     if(keyframe)
 251         maxband = mpc8_get_mod_golomb(gb, c->maxbands + 1);
 252     else{
 253         maxband = c->last_max_band + get_vlc2(gb, band_vlc.table, MPC8_BANDS_BITS, 2);
 254         if(maxband > 32) maxband -= 33;
 255     }
 256     c->last_max_band = maxband;
 257
 258     /* read subband indexes */
 259     if(maxband){
 260         last[0] = last[1] = 0;
 261         for(i = maxband - 1; i >= 0; i--){
 262             for(ch = 0; ch < 2; ch++){
 263                 last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
 264                 if(last[ch] > 15) last[ch] -= 17;
 265                 bands[i].res[ch] = last[ch];
 266             }
 267         }
 268         if(c->MSS){
 269             int mask;
 270
 271             cnt = 0;
 272             for(i = 0; i < maxband; i++)
 273                 if(bands[i].res[0] || bands[i].res[1])
 274                     cnt++;
 275             t = mpc8_get_mod_golomb(gb, cnt);
 276             mask = mpc8_get_mask(gb, cnt, t);
 277             for(i = maxband - 1; i >= 0; i--)
 278                 if(bands[i].res[0] || bands[i].res[1]){
 279                     bands[i].msf = mask & 1;
 280                     mask >>= 1;
 281                 }
 282         }
 283     }
 284     for(i = maxband; i < c->maxbands; i++)
 285         bands[i].res[0] = bands[i].res[1] = 0;
 286
 287     if(keyframe){
 288         for(i = 0; i < 32; i++)
 289             c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
 290     }
 291
 292     for(i = 0; i < maxband; i++){
 293         if(bands[i].res[0] || bands[i].res[1]){
 294             cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
 295             if(cnt >= 0){
 296                 t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
 297                 if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
 298                 if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
 299             }
 300         }
 301     }
 302
 303     for(i = 0; i < maxband; i++){
 304         for(ch = 0; ch < 2; ch++){
 305             if(!bands[i].res[ch]) continue;
 306
 307             if(c->oldDSCF[ch][i]){
 308                 bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
 309                 c->oldDSCF[ch][i] = 0;
 310             }else{
 311                 t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
 312                 if(t == 64)
 313                     t += get_bits(gb, 6);
 314                 bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
 315             }
 316             for(j = 0; j < 2; j++){
 317                 if((bands[i].scfi[ch] << j) & 2)
 318                     bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
 319                 else{
 320                     t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
 321                     if(t == 31)
 322                         t = 64 + get_bits(gb, 6);
 323                     bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
 324                 }
 325             }
 326         }
 327     }
 328
 329     for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
 330         for(ch = 0; ch < 2; ch++){
 331             res = bands[i].res[ch];
 332             switch(res){
 333             case -1:
 334                 for(j = 0; j < SAMPLES_PER_BAND; j++)
 335                     c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
 336                 break;
 337             case 0:
 338                 break;
 339             case 1:
 340                 for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
 341                     cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
 342                     t = mpc8_get_mask(gb, 18, cnt);
 343                     for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
 344                         c->Q[ch][off + j + k] = (t & 0x20000) ? (get_bits1(gb) << 1) - 1 : 0;
 345                 }
 346                 break;
 347             case 2:
 348                 cnt = 6;//2*mpc8_thres[res]
 349                 for(j = 0; j < SAMPLES_PER_BAND; j += 3){
 350                     t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
 351                     c->Q[ch][off + j + 0] = mpc8_idx50[t];
 352                     c->Q[ch][off + j + 1] = mpc8_idx51[t];
 353                     c->Q[ch][off + j + 2] = mpc8_idx52[t];
 354                     cnt = (cnt >> 1) + mpc8_huffq2[t];
 355                 }
 356                 break;
 357             case 3:
 358             case 4:
 359                 for(j = 0; j < SAMPLES_PER_BAND; j += 2){
 360                     t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
 361                     c->Q[ch][off + j + 1] = t >> 4;
 362                     c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
 363                 }
 364                 break;
 365             case 5:
 366             case 6:
 367             case 7:
 368             case 8:
 369                 cnt = 2 * mpc8_thres[res];
 370                 for(j = 0; j < SAMPLES_PER_BAND; j++){
 371                     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];
 372                     c->Q[ch][off + j] = t;
 373                     cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
 374                 }
 375                 break;
 376             default:
 377                 for(j = 0; j < SAMPLES_PER_BAND; j++){
 378                     c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
 379                     if(res != 9){
 380                         c->Q[ch][off + j] <<= res - 9;
 381                         c->Q[ch][off + j] |= get_bits(gb, res - 9);
 382                     }
 383                     c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
 384                 }
 385             }
 386         }
 387     }
 388
 389     ff_mpc_dequantize_and_synth(c, maxband, data);
 390
 391     c->cur_frame++;
 392
 393     c->last_bits_used = get_bits_count(gb);
 394     if(c->cur_frame >= c->frames)
 395         c->cur_frame = 0;
 396     *data_size =  MPC_FRAME_SIZE * 4;
 397
 398     return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
 399 }
 400
 401 AVCodec mpc8_decoder = {
 402     "mpc8",
 403     CODEC_TYPE_AUDIO,
 404     CODEC_ID_MUSEPACK8,
 405     sizeof(MPCContext),
 406     mpc8_decode_init,
 407     NULL,
 408     NULL,
 409     mpc8_decode_frame,
 410     .long_name = NULL_IF_CONFIG_SMALL("Musepack SV8"),
 411 };