libavcodec/mpc.c

   1 /*
   2  * Musepack decoder
   3  * Copyright (c) 2006 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 /**
  24  * @file mpc.c Musepack decoder
  25  * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
  26  * divided into 32 subbands.
  27  */
  28
  29 #include "avcodec.h"
  30 #include "bitstream.h"
  31 #include "dsputil.h"
  32 #include "random.h"
  33
  34 #ifdef CONFIG_MPEGAUDIO_HP
  35 #define USE_HIGHPRECISION
  36 #endif
  37 #include "mpegaudio.h"
  38
  39 #include "mpcdata.h"
  40
  41 #define BANDS            32
  42 #define SAMPLES_PER_BAND 36
  43 #define MPC_FRAME_SIZE   (BANDS * SAMPLES_PER_BAND)
  44
  45 static VLC scfi_vlc, dscf_vlc, hdr_vlc, quant_vlc[MPC7_QUANT_VLC_TABLES][2];
  46
  47 static DECLARE_ALIGNED_16(MPA_INT, mpa_window[512]);
  48
  49 typedef struct {
  50     DSPContext dsp;
  51     int IS, MSS, gapless;
  52     int lastframelen, bands;
  53     int oldDSCF[2][BANDS];
  54     AVRandomState rnd;
  55     int frames_to_skip;
  56     /* for synthesis */
  57     DECLARE_ALIGNED_16(MPA_INT, synth_buf[MPA_MAX_CHANNELS][512*2]);
  58     int synth_buf_offset[MPA_MAX_CHANNELS];
  59     DECLARE_ALIGNED_16(int32_t, sb_samples[MPA_MAX_CHANNELS][36][SBLIMIT]);
  60 } MPCContext;
  61
  62 /** Subband structure - hold all variables for each subband */
  63 typedef struct {
  64     int msf; ///< mid-stereo flag
  65     int res[2];
  66     int scfi[2];
  67     int scf_idx[2][3];
  68     int Q[2];
  69 }Band;
  70
  71 static int mpc7_decode_init(AVCodecContext * avctx)
  72 {
  73     int i, j;
  74     MPCContext *c = avctx->priv_data;
  75     GetBitContext gb;
  76     uint8_t buf[16];
  77     static int vlc_inited = 0;
  78
  79     if(avctx->extradata_size < 16){
  80         av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
  81         return -1;
  82     }
  83     memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
  84     av_init_random(0xDEADBEEF, &c->rnd);
  85     dsputil_init(&c->dsp, avctx);
  86     c->dsp.bswap_buf(buf, avctx->extradata, 4);
  87     ff_mpa_synth_init(mpa_window);
  88     init_get_bits(&gb, buf, 128);
  89
  90     c->IS = get_bits1(&gb);
  91     c->MSS = get_bits1(&gb);
  92     c->bands = get_bits(&gb, 6);
  93     if(c->bands >= BANDS){
  94         av_log(avctx, AV_LOG_ERROR, "Too many bands: %i\n", c->bands);
  95         return -1;
  96     }
  97     skip_bits(&gb, 88);
  98     c->gapless = get_bits1(&gb);
  99     c->lastframelen = get_bits(&gb, 11);
 100     av_log(avctx, AV_LOG_DEBUG, "IS: %d, MSS: %d, TG: %d, LFL: %d, bands: %d\n",
 101             c->IS, c->MSS, c->gapless, c->lastframelen, c->bands);
 102     c->frames_to_skip = 0;
 103
 104     if(vlc_inited) return 0;
 105     av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
 106     if(init_vlc(&scfi_vlc, MPC7_SCFI_BITS, MPC7_SCFI_SIZE,
 107                 &mpc7_scfi[1], 2, 1,
 108                 &mpc7_scfi[0], 2, 1, INIT_VLC_USE_STATIC)){
 109         av_log(avctx, AV_LOG_ERROR, "Cannot init SCFI VLC\n");
 110         return -1;
 111     }
 112     if(init_vlc(&dscf_vlc, MPC7_DSCF_BITS, MPC7_DSCF_SIZE,
 113                 &mpc7_dscf[1], 2, 1,
 114                 &mpc7_dscf[0], 2, 1, INIT_VLC_USE_STATIC)){
 115         av_log(avctx, AV_LOG_ERROR, "Cannot init DSCF VLC\n");
 116         return -1;
 117     }
 118     if(init_vlc(&hdr_vlc, MPC7_HDR_BITS, MPC7_HDR_SIZE,
 119                 &mpc7_hdr[1], 2, 1,
 120                 &mpc7_hdr[0], 2, 1, INIT_VLC_USE_STATIC)){
 121         av_log(avctx, AV_LOG_ERROR, "Cannot init HDR VLC\n");
 122         return -1;
 123     }
 124     for(i = 0; i < MPC7_QUANT_VLC_TABLES; i++){
 125         for(j = 0; j < 2; j++){
 126             if(init_vlc(&quant_vlc[i][j], 9, mpc7_quant_vlc_sizes[i],
 127                         &mpc7_quant_vlc[i][j][1], 4, 2,
 128                         &mpc7_quant_vlc[i][j][0], 4, 2, INIT_VLC_USE_STATIC)){
 129                 av_log(avctx, AV_LOG_ERROR, "Cannot init QUANT VLC %i,%i\n",i,j);
 130                 return -1;
 131             }
 132         }
 133     }
 134     vlc_inited = 1;
 135     return 0;
 136 }
 137
 138 /**
 139  * Process decoded Musepack data and produce PCM
 140  * @todo make it available for MPC8 and MPC6
 141  */
 142 static void mpc_synth(MPCContext *c, int16_t *out)
 143 {
 144     int dither_state = 0;
 145     int i, ch;
 146     OUT_INT samples[MPA_MAX_CHANNELS * MPA_FRAME_SIZE], *samples_ptr;
 147
 148     for(ch = 0;  ch < 2; ch++){
 149         samples_ptr = samples + ch;
 150         for(i = 0; i < SAMPLES_PER_BAND; i++) {
 151             ff_mpa_synth_filter(c->synth_buf[ch], &(c->synth_buf_offset[ch]),
 152                                 mpa_window, &dither_state,
 153                                 samples_ptr, 2,
 154                                 c->sb_samples[ch][i]);
 155             samples_ptr += 64;
 156         }
 157     }
 158     for(i = 0; i < MPC_FRAME_SIZE*2; i++)
 159         *out++=samples[i];
 160 }
 161
 162 /**
 163  * Fill samples for given subband
 164  */
 165 static inline void idx_to_quant(MPCContext *c, GetBitContext *gb, int idx, int *dst)
 166 {
 167     int i, i1, t;
 168     switch(idx){
 169     case -1:
 170         for(i = 0; i < SAMPLES_PER_BAND; i++){
 171             *dst++ = (av_random(&c->rnd) & 0x3FC) - 510;
 172         }
 173         break;
 174     case 1:
 175         i1 = get_bits1(gb);
 176         for(i = 0; i < SAMPLES_PER_BAND/3; i++){
 177             t = get_vlc2(gb, quant_vlc[0][i1].table, 9, 2);
 178             *dst++ = mpc_idx30[t];
 179             *dst++ = mpc_idx31[t];
 180             *dst++ = mpc_idx32[t];
 181         }
 182         break;
 183     case 2:
 184         i1 = get_bits1(gb);
 185         for(i = 0; i < SAMPLES_PER_BAND/2; i++){
 186             t = get_vlc2(gb, quant_vlc[1][i1].table, 9, 2);
 187             *dst++ = mpc_idx50[t];
 188             *dst++ = mpc_idx51[t];
 189         }
 190         break;
 191     case  3: case  4: case  5: case  6: case  7:
 192         i1 = get_bits1(gb);
 193         for(i = 0; i < SAMPLES_PER_BAND; i++)
 194             *dst++ = get_vlc2(gb, quant_vlc[idx-1][i1].table, 9, 2) - mpc7_quant_vlc_off[idx-1];
 195         break;
 196     case  8: case  9: case 10: case 11: case 12:
 197     case 13: case 14: case 15: case 16: case 17:
 198         t = (1 << (idx - 2)) - 1;
 199         for(i = 0; i < SAMPLES_PER_BAND; i++)
 200             *dst++ = get_bits(gb, idx - 1) - t;
 201         break;
 202     default: // case 0 and -2..-17
 203         return;
 204     }
 205 }
 206
 207 static int mpc7_decode_frame(AVCodecContext * avctx,
 208                             void *data, int *data_size,
 209                             uint8_t * buf, int buf_size)
 210 {
 211     MPCContext *c = avctx->priv_data;
 212     GetBitContext gb;
 213     uint8_t *bits;
 214     int i, j, ch, t;
 215     int mb = -1;
 216     Band bands[BANDS];
 217     int Q[2][MPC_FRAME_SIZE];
 218     int off;
 219     float mul;
 220     int bits_used, bits_avail;
 221
 222     memset(bands, 0, sizeof(bands));
 223     if(buf_size <= 4){
 224         av_log(avctx, AV_LOG_ERROR, "Too small buffer passed (%i bytes)\n", buf_size);
 225     }
 226
 227     bits = av_malloc(((buf_size - 1) & ~3) + FF_INPUT_BUFFER_PADDING_SIZE);
 228     c->dsp.bswap_buf(bits, buf + 4, (buf_size - 4) >> 2);
 229     init_get_bits(&gb, bits, (buf_size - 4)* 8);
 230     skip_bits(&gb, buf[0]);
 231
 232     /* read subband indexes */
 233     for(i = 0; i <= c->bands; i++){
 234         for(ch = 0; ch < 2; ch++){
 235             if(i) t = get_vlc2(&gb, hdr_vlc.table, MPC7_HDR_BITS, 1) - 5;
 236             if(!i || (t == 4)) bands[i].res[ch] = get_bits(&gb, 4);
 237             else bands[i].res[ch] = bands[i-1].res[ch] + t;
 238         }
 239
 240         if(bands[i].res[0] || bands[i].res[1]){
 241             mb = i;
 242             if(c->MSS) bands[i].msf = get_bits1(&gb);
 243         }
 244     }
 245     /* get scale indexes coding method */
 246     for(i = 0; i <= mb; i++)
 247         for(ch = 0; ch < 2; ch++)
 248             if(bands[i].res[ch]) bands[i].scfi[ch] = get_vlc2(&gb, scfi_vlc.table, MPC7_SCFI_BITS, 1);
 249     /* get scale indexes */
 250     for(i = 0; i <= mb; i++){
 251         for(ch = 0; ch < 2; ch++){
 252             if(bands[i].res[ch]){
 253                 bands[i].scf_idx[ch][2] = c->oldDSCF[ch][i];
 254                 t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
 255                 bands[i].scf_idx[ch][0] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][2] + t);
 256                 switch(bands[i].scfi[ch]){
 257                 case 0:
 258                     t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
 259                     bands[i].scf_idx[ch][1] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][0] + t);
 260                     t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
 261                     bands[i].scf_idx[ch][2] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][1] + t);
 262                     break;
 263                 case 1:
 264                     t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
 265                     bands[i].scf_idx[ch][1] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][0] + t);
 266                     bands[i].scf_idx[ch][2] = bands[i].scf_idx[ch][1];
 267                     break;
 268                 case 2:
 269                     bands[i].scf_idx[ch][1] = bands[i].scf_idx[ch][0];
 270                     t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
 271                     bands[i].scf_idx[ch][2] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][1] + t);
 272                     break;
 273                 case 3:
 274                     bands[i].scf_idx[ch][2] = bands[i].scf_idx[ch][1] = bands[i].scf_idx[ch][0];
 275                     break;
 276                 }
 277                 c->oldDSCF[ch][i] = bands[i].scf_idx[ch][2];
 278             }
 279         }
 280     }
 281     /* get quantizers */
 282     memset(Q, 0, sizeof(Q));
 283     off = 0;
 284     for(i = 0; i < BANDS; i++, off += SAMPLES_PER_BAND)
 285         for(ch = 0; ch < 2; ch++)
 286             idx_to_quant(c, &gb, bands[i].res[ch], Q[ch] + off);
 287     /* dequantize */
 288     memset(c->sb_samples, 0, sizeof(c->sb_samples));
 289     off = 0;
 290     for(i = 0; i <= mb; i++, off += SAMPLES_PER_BAND){
 291         for(ch = 0; ch < 2; ch++){
 292             if(bands[i].res[ch]){
 293                 j = 0;
 294                 mul = mpc_CC[bands[i].res[ch]] * mpc7_SCF[bands[i].scf_idx[ch][0]];
 295                 for(; j < 12; j++)
 296                     c->sb_samples[ch][j][i] = mul * Q[ch][j + off];
 297                 mul = mpc_CC[bands[i].res[ch]] * mpc7_SCF[bands[i].scf_idx[ch][1]];
 298                 for(; j < 24; j++)
 299                     c->sb_samples[ch][j][i] = mul * Q[ch][j + off];
 300                 mul = mpc_CC[bands[i].res[ch]] * mpc7_SCF[bands[i].scf_idx[ch][2]];
 301                 for(; j < 36; j++)
 302                     c->sb_samples[ch][j][i] = mul * Q[ch][j + off];
 303             }
 304         }
 305         if(bands[i].msf){
 306             int t1, t2;
 307             for(j = 0; j < SAMPLES_PER_BAND; j++){
 308                 t1 = c->sb_samples[0][j][i];
 309                 t2 = c->sb_samples[1][j][i];
 310                 c->sb_samples[0][j][i] = t1 + t2;
 311                 c->sb_samples[1][j][i] = t1 - t2;
 312             }
 313         }
 314     }
 315
 316     mpc_synth(c, data);
 317
 318     av_free(bits);
 319
 320     bits_used = get_bits_count(&gb);
 321     bits_avail = (buf_size - 4) * 8;
 322     if(!buf[1] && ((bits_avail < bits_used) || (bits_used + 32 <= bits_avail))){
 323         av_log(NULL,0, "Error decoding frame: used %i of %i bits\n", bits_used, bits_avail);
 324         return -1;
 325     }
 326     if(c->frames_to_skip){
 327         c->frames_to_skip--;
 328         *data_size = 0;
 329         return buf_size;
 330     }
 331     *data_size = (buf[1] ? c->lastframelen : MPC_FRAME_SIZE) * 4;
 332
 333     return buf_size;
 334 }
 335
 336 static void mpc7_decode_flush(AVCodecContext *avctx)
 337 {
 338     MPCContext *c = avctx->priv_data;
 339
 340     memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
 341     c->frames_to_skip = 32;
 342 }
 343
 344 AVCodec mpc7_decoder = {
 345     "mpc sv7",
 346     CODEC_TYPE_AUDIO,
 347     CODEC_ID_MUSEPACK7,
 348     sizeof(MPCContext),
 349     mpc7_decode_init,
 350     NULL,
 351     NULL,
 352     mpc7_decode_frame,
 353     .flush = mpc7_decode_flush,
 354 };