tizen/distrib/libav/libavcodec/shorten.c

   1 /*
   2  * Shorten decoder
   3  * Copyright (c) 2005 Jeff Muizelaar
   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  * Shorten decoder
  25  * @author Jeff Muizelaar
  26  *
  27  */
  28
  29 #include <limits.h>
  30 #include "avcodec.h"
  31 #include "get_bits.h"
  32 #include "golomb.h"
  33
  34 #define MAX_CHANNELS 8
  35 #define MAX_BLOCKSIZE 65535
  36
  37 #define OUT_BUFFER_SIZE 16384
  38
  39 #define ULONGSIZE 2
  40
  41 #define WAVE_FORMAT_PCM 0x0001
  42
  43 #define DEFAULT_BLOCK_SIZE 256
  44
  45 #define TYPESIZE 4
  46 #define CHANSIZE 0
  47 #define LPCQSIZE 2
  48 #define ENERGYSIZE 3
  49 #define BITSHIFTSIZE 2
  50
  51 #define TYPE_S16HL 3
  52 #define TYPE_S16LH 5
  53
  54 #define NWRAP 3
  55 #define NSKIPSIZE 1
  56
  57 #define LPCQUANT 5
  58 #define V2LPCQOFFSET (1 << LPCQUANT)
  59
  60 #define FNSIZE 2
  61 #define FN_DIFF0        0
  62 #define FN_DIFF1        1
  63 #define FN_DIFF2        2
  64 #define FN_DIFF3        3
  65 #define FN_QUIT         4
  66 #define FN_BLOCKSIZE    5
  67 #define FN_BITSHIFT     6
  68 #define FN_QLPC         7
  69 #define FN_ZERO         8
  70 #define FN_VERBATIM     9
  71
  72 #define VERBATIM_CKSIZE_SIZE 5
  73 #define VERBATIM_BYTE_SIZE 8
  74 #define CANONICAL_HEADER_SIZE 44
  75
  76 typedef struct ShortenContext {
  77     AVCodecContext *avctx;
  78     GetBitContext gb;
  79
  80     int min_framesize, max_framesize;
  81     int channels;
  82
  83     int32_t *decoded[MAX_CHANNELS];
  84     int32_t *offset[MAX_CHANNELS];
  85     int *coeffs;
  86     uint8_t *bitstream;
  87     int bitstream_size;
  88     int bitstream_index;
  89     unsigned int allocated_bitstream_size;
  90     int header_size;
  91     uint8_t header[OUT_BUFFER_SIZE];
  92     int version;
  93     int cur_chan;
  94     int bitshift;
  95     int nmean;
  96     int internal_ftype;
  97     int nwrap;
  98     int blocksize;
  99     int bitindex;
 100     int32_t lpcqoffset;
 101 } ShortenContext;
 102
 103 static av_cold int shorten_decode_init(AVCodecContext * avctx)
 104 {
 105     ShortenContext *s = avctx->priv_data;
 106     s->avctx = avctx;
 107     avctx->sample_fmt = AV_SAMPLE_FMT_S16;
 108
 109     return 0;
 110 }
 111
 112 static int allocate_buffers(ShortenContext *s)
 113 {
 114     int i, chan;
 115     int *coeffs;
 116
 117     for (chan=0; chan<s->channels; chan++) {
 118         if(FFMAX(1, s->nmean) >= UINT_MAX/sizeof(int32_t)){
 119             av_log(s->avctx, AV_LOG_ERROR, "nmean too large\n");
 120             return -1;
 121         }
 122         if(s->blocksize + s->nwrap >= UINT_MAX/sizeof(int32_t) || s->blocksize + s->nwrap <= (unsigned)s->nwrap){
 123             av_log(s->avctx, AV_LOG_ERROR, "s->blocksize + s->nwrap too large\n");
 124             return -1;
 125         }
 126
 127         s->offset[chan] = av_realloc(s->offset[chan], sizeof(int32_t)*FFMAX(1, s->nmean));
 128
 129         s->decoded[chan] = av_realloc(s->decoded[chan], sizeof(int32_t)*(s->blocksize + s->nwrap));
 130         for (i=0; i<s->nwrap; i++)
 131             s->decoded[chan][i] = 0;
 132         s->decoded[chan] += s->nwrap;
 133     }
 134
 135     coeffs = av_realloc(s->coeffs, s->nwrap * sizeof(*s->coeffs));
 136     if (!coeffs)
 137         return AVERROR(ENOMEM);
 138     s->coeffs = coeffs;
 139
 140     return 0;
 141 }
 142
 143
 144 static inline unsigned int get_uint(ShortenContext *s, int k)
 145 {
 146     if (s->version != 0)
 147         k = get_ur_golomb_shorten(&s->gb, ULONGSIZE);
 148     return get_ur_golomb_shorten(&s->gb, k);
 149 }
 150
 151
 152 static void fix_bitshift(ShortenContext *s, int32_t *buffer)
 153 {
 154     int i;
 155
 156     if (s->bitshift != 0)
 157         for (i = 0; i < s->blocksize; i++)
 158             buffer[s->nwrap + i] <<= s->bitshift;
 159 }
 160
 161
 162 static void init_offset(ShortenContext *s)
 163 {
 164     int32_t mean = 0;
 165     int  chan, i;
 166     int nblock = FFMAX(1, s->nmean);
 167     /* initialise offset */
 168     switch (s->internal_ftype)
 169     {
 170         case TYPE_S16HL:
 171         case TYPE_S16LH:
 172             mean = 0;
 173             break;
 174         default:
 175             av_log(s->avctx, AV_LOG_ERROR, "unknown audio type");
 176             abort();
 177     }
 178
 179     for (chan = 0; chan < s->channels; chan++)
 180         for (i = 0; i < nblock; i++)
 181             s->offset[chan][i] = mean;
 182 }
 183
 184 static inline int get_le32(GetBitContext *gb)
 185 {
 186     return av_bswap32(get_bits_long(gb, 32));
 187 }
 188
 189 static inline short get_le16(GetBitContext *gb)
 190 {
 191     return av_bswap16(get_bits_long(gb, 16));
 192 }
 193
 194 static int decode_wave_header(AVCodecContext *avctx, uint8_t *header, int header_size)
 195 {
 196     GetBitContext hb;
 197     int len;
 198     short wave_format;
 199
 200     init_get_bits(&hb, header, header_size*8);
 201     if (get_le32(&hb) != MKTAG('R','I','F','F')) {
 202         av_log(avctx, AV_LOG_ERROR, "missing RIFF tag\n");
 203         return -1;
 204     }
 205
 206     skip_bits_long(&hb, 32);    /* chunk_size */
 207
 208     if (get_le32(&hb) != MKTAG('W','A','V','E')) {
 209         av_log(avctx, AV_LOG_ERROR, "missing WAVE tag\n");
 210         return -1;
 211     }
 212
 213     while (get_le32(&hb) != MKTAG('f','m','t',' ')) {
 214         len = get_le32(&hb);
 215         skip_bits(&hb, 8*len);
 216     }
 217     len = get_le32(&hb);
 218
 219     if (len < 16) {
 220         av_log(avctx, AV_LOG_ERROR, "fmt chunk was too short\n");
 221         return -1;
 222     }
 223
 224     wave_format = get_le16(&hb);
 225
 226     switch (wave_format) {
 227         case WAVE_FORMAT_PCM:
 228             break;
 229         default:
 230             av_log(avctx, AV_LOG_ERROR, "unsupported wave format\n");
 231             return -1;
 232     }
 233
 234     avctx->channels = get_le16(&hb);
 235     avctx->sample_rate = get_le32(&hb);
 236     avctx->bit_rate = get_le32(&hb) * 8;
 237     avctx->block_align = get_le16(&hb);
 238     avctx->bits_per_coded_sample = get_le16(&hb);
 239
 240     if (avctx->bits_per_coded_sample != 16) {
 241         av_log(avctx, AV_LOG_ERROR, "unsupported number of bits per sample\n");
 242         return -1;
 243     }
 244
 245     len -= 16;
 246     if (len > 0)
 247         av_log(avctx, AV_LOG_INFO, "%d header bytes unparsed\n", len);
 248
 249     return 0;
 250 }
 251
 252 static int16_t * interleave_buffer(int16_t *samples, int nchan, int blocksize, int32_t **buffer) {
 253     int i, chan;
 254     for (i=0; i<blocksize; i++)
 255         for (chan=0; chan < nchan; chan++)
 256             *samples++ = FFMIN(buffer[chan][i], 32768);
 257     return samples;
 258 }
 259
 260 static void decode_subframe_lpc(ShortenContext *s, int channel, int residual_size, int pred_order)
 261 {
 262     int sum, i, j;
 263     int *coeffs = s->coeffs;
 264
 265     for (i=0; i<pred_order; i++)
 266         coeffs[i] = get_sr_golomb_shorten(&s->gb, LPCQUANT);
 267
 268     for (i=0; i < s->blocksize; i++) {
 269         sum = s->lpcqoffset;
 270         for (j=0; j<pred_order; j++)
 271             sum += coeffs[j] * s->decoded[channel][i-j-1];
 272         s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + (sum >> LPCQUANT);
 273     }
 274 }
 275
 276
 277 static int shorten_decode_frame(AVCodecContext *avctx,
 278         void *data, int *data_size,
 279         AVPacket *avpkt)
 280 {
 281     const uint8_t *buf = avpkt->data;
 282     int buf_size = avpkt->size;
 283     ShortenContext *s = avctx->priv_data;
 284     int i, input_buf_size = 0;
 285     int16_t *samples = data;
 286     if(s->max_framesize == 0){
 287         s->max_framesize= 1024; // should hopefully be enough for the first header
 288         s->bitstream= av_fast_realloc(s->bitstream, &s->allocated_bitstream_size, s->max_framesize);
 289     }
 290
 291     if(1 && s->max_framesize){//FIXME truncated
 292         buf_size= FFMIN(buf_size, s->max_framesize - s->bitstream_size);
 293         input_buf_size= buf_size;
 294
 295         if(s->bitstream_index + s->bitstream_size + buf_size > s->allocated_bitstream_size){
 296             //                printf("memmove\n");
 297             memmove(s->bitstream, &s->bitstream[s->bitstream_index], s->bitstream_size);
 298             s->bitstream_index=0;
 299         }
 300         memcpy(&s->bitstream[s->bitstream_index + s->bitstream_size], buf, buf_size);
 301         buf= &s->bitstream[s->bitstream_index];
 302         buf_size += s->bitstream_size;
 303         s->bitstream_size= buf_size;
 304
 305         if(buf_size < s->max_framesize){
 306             *data_size = 0;
 307             return input_buf_size;
 308         }
 309     }
 310     init_get_bits(&s->gb, buf, buf_size*8);
 311     skip_bits(&s->gb, s->bitindex);
 312     if (!s->blocksize)
 313     {
 314         int maxnlpc = 0;
 315         /* shorten signature */
 316         if (get_bits_long(&s->gb, 32) != AV_RB32("ajkg")) {
 317             av_log(s->avctx, AV_LOG_ERROR, "missing shorten magic 'ajkg'\n");
 318             return -1;
 319         }
 320
 321         s->lpcqoffset = 0;
 322         s->blocksize = DEFAULT_BLOCK_SIZE;
 323         s->channels = 1;
 324         s->nmean = -1;
 325         s->version = get_bits(&s->gb, 8);
 326         s->internal_ftype = get_uint(s, TYPESIZE);
 327
 328         s->channels = get_uint(s, CHANSIZE);
 329         if (s->channels > MAX_CHANNELS) {
 330             av_log(s->avctx, AV_LOG_ERROR, "too many channels: %d\n", s->channels);
 331             return -1;
 332         }
 333
 334         /* get blocksize if version > 0 */
 335         if (s->version > 0) {
 336             int skip_bytes;
 337             s->blocksize = get_uint(s, av_log2(DEFAULT_BLOCK_SIZE));
 338             maxnlpc = get_uint(s, LPCQSIZE);
 339             s->nmean = get_uint(s, 0);
 340
 341             skip_bytes = get_uint(s, NSKIPSIZE);
 342             for (i=0; i<skip_bytes; i++) {
 343                 skip_bits(&s->gb, 8);
 344             }
 345         }
 346         s->nwrap = FFMAX(NWRAP, maxnlpc);
 347
 348         if (allocate_buffers(s))
 349             return -1;
 350
 351         init_offset(s);
 352
 353         if (s->version > 1)
 354             s->lpcqoffset = V2LPCQOFFSET;
 355
 356         if (get_ur_golomb_shorten(&s->gb, FNSIZE) != FN_VERBATIM) {
 357             av_log(s->avctx, AV_LOG_ERROR, "missing verbatim section at beginning of stream\n");
 358             return -1;
 359         }
 360
 361         s->header_size = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);
 362         if (s->header_size >= OUT_BUFFER_SIZE || s->header_size < CANONICAL_HEADER_SIZE) {
 363             av_log(s->avctx, AV_LOG_ERROR, "header is wrong size: %d\n", s->header_size);
 364             return -1;
 365         }
 366
 367         for (i=0; i<s->header_size; i++)
 368             s->header[i] = (char)get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);
 369
 370         if (decode_wave_header(avctx, s->header, s->header_size) < 0)
 371             return -1;
 372
 373         s->cur_chan = 0;
 374         s->bitshift = 0;
 375     }
 376     else
 377     {
 378         int cmd;
 379         int len;
 380         cmd = get_ur_golomb_shorten(&s->gb, FNSIZE);
 381         switch (cmd) {
 382             case FN_ZERO:
 383             case FN_DIFF0:
 384             case FN_DIFF1:
 385             case FN_DIFF2:
 386             case FN_DIFF3:
 387             case FN_QLPC:
 388                 {
 389                     int residual_size = 0;
 390                     int channel = s->cur_chan;
 391                     int32_t coffset;
 392                     if (cmd != FN_ZERO) {
 393                         residual_size = get_ur_golomb_shorten(&s->gb, ENERGYSIZE);
 394                         /* this is a hack as version 0 differed in defintion of get_sr_golomb_shorten */
 395                         if (s->version == 0)
 396                             residual_size--;
 397                     }
 398
 399                     if (s->nmean == 0)
 400                         coffset = s->offset[channel][0];
 401                     else {
 402                         int32_t sum = (s->version < 2) ? 0 : s->nmean / 2;
 403                         for (i=0; i<s->nmean; i++)
 404                             sum += s->offset[channel][i];
 405                         coffset = sum / s->nmean;
 406                         if (s->version >= 2)
 407                             coffset >>= FFMIN(1, s->bitshift);
 408                     }
 409                     switch (cmd) {
 410                         case FN_ZERO:
 411                             for (i=0; i<s->blocksize; i++)
 412                                 s->decoded[channel][i] = 0;
 413                             break;
 414                         case FN_DIFF0:
 415                             for (i=0; i<s->blocksize; i++)
 416                                 s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + coffset;
 417                             break;
 418                         case FN_DIFF1:
 419                             for (i=0; i<s->blocksize; i++)
 420                                 s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + s->decoded[channel][i - 1];
 421                             break;
 422                         case FN_DIFF2:
 423                             for (i=0; i<s->blocksize; i++)
 424                                 s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + 2*s->decoded[channel][i-1]
 425                                                                                                       -   s->decoded[channel][i-2];
 426                             break;
 427                         case FN_DIFF3:
 428                             for (i=0; i<s->blocksize; i++)
 429                                 s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + 3*s->decoded[channel][i-1]
 430                                                                                                       - 3*s->decoded[channel][i-2]
 431                                                                                                       +   s->decoded[channel][i-3];
 432                             break;
 433                         case FN_QLPC:
 434                             {
 435                                 int pred_order = get_ur_golomb_shorten(&s->gb, LPCQSIZE);
 436                                 if (pred_order > s->nwrap) {
 437                                     av_log(avctx, AV_LOG_ERROR,
 438                                            "invalid pred_order %d\n",
 439                                            pred_order);
 440                                     return -1;
 441                                 }
 442                                 for (i=0; i<pred_order; i++)
 443                                     s->decoded[channel][i - pred_order] -= coffset;
 444                                 decode_subframe_lpc(s, channel, residual_size, pred_order);
 445                                 if (coffset != 0)
 446                                     for (i=0; i < s->blocksize; i++)
 447                                         s->decoded[channel][i] += coffset;
 448                             }
 449                     }
 450                     if (s->nmean > 0) {
 451                         int32_t sum = (s->version < 2) ? 0 : s->blocksize / 2;
 452                         for (i=0; i<s->blocksize; i++)
 453                             sum += s->decoded[channel][i];
 454
 455                         for (i=1; i<s->nmean; i++)
 456                             s->offset[channel][i-1] = s->offset[channel][i];
 457
 458                         if (s->version < 2)
 459                             s->offset[channel][s->nmean - 1] = sum / s->blocksize;
 460                         else
 461                             s->offset[channel][s->nmean - 1] = (sum / s->blocksize) << s->bitshift;
 462                     }
 463                     for (i=-s->nwrap; i<0; i++)
 464                         s->decoded[channel][i] = s->decoded[channel][i + s->blocksize];
 465
 466                     fix_bitshift(s, s->decoded[channel]);
 467
 468                     s->cur_chan++;
 469                     if (s->cur_chan == s->channels) {
 470                         samples = interleave_buffer(samples, s->channels, s->blocksize, s->decoded);
 471                         s->cur_chan = 0;
 472                         goto frame_done;
 473                     }
 474                     break;
 475                 }
 476                 break;
 477             case FN_VERBATIM:
 478                 len = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);
 479                 while (len--) {
 480                     get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);
 481                 }
 482                 break;
 483             case FN_BITSHIFT:
 484                 s->bitshift = get_ur_golomb_shorten(&s->gb, BITSHIFTSIZE);
 485                 break;
 486             case FN_BLOCKSIZE:
 487                 s->blocksize = get_uint(s, av_log2(s->blocksize));
 488                 break;
 489             case FN_QUIT:
 490                 *data_size = 0;
 491                 return buf_size;
 492                 break;
 493             default:
 494                 av_log(avctx, AV_LOG_ERROR, "unknown shorten function %d\n", cmd);
 495                 return -1;
 496                 break;
 497         }
 498     }
 499 frame_done:
 500     *data_size = (int8_t *)samples - (int8_t *)data;
 501
 502     //    s->last_blocksize = s->blocksize;
 503     s->bitindex = get_bits_count(&s->gb) - 8*((get_bits_count(&s->gb))/8);
 504     i= (get_bits_count(&s->gb))/8;
 505     if (i > buf_size) {
 506         av_log(s->avctx, AV_LOG_ERROR, "overread: %d\n", i - buf_size);
 507         s->bitstream_size=0;
 508         s->bitstream_index=0;
 509         return -1;
 510     }
 511     if (s->bitstream_size) {
 512         s->bitstream_index += i;
 513         s->bitstream_size  -= i;
 514         return input_buf_size;
 515     } else
 516         return i;
 517 }
 518
 519 static av_cold int shorten_decode_close(AVCodecContext *avctx)
 520 {
 521     ShortenContext *s = avctx->priv_data;
 522     int i;
 523
 524     for (i = 0; i < s->channels; i++) {
 525         s->decoded[i] -= s->nwrap;
 526         av_freep(&s->decoded[i]);
 527         av_freep(&s->offset[i]);
 528     }
 529     av_freep(&s->bitstream);
 530     av_freep(&s->coeffs);
 531     return 0;
 532 }
 533
 534 static void shorten_flush(AVCodecContext *avctx){
 535     ShortenContext *s = avctx->priv_data;
 536
 537     s->bitstream_size=
 538         s->bitstream_index= 0;
 539 }
 540
 541 AVCodec ff_shorten_decoder = {
 542     "shorten",
 543     AVMEDIA_TYPE_AUDIO,
 544     CODEC_ID_SHORTEN,
 545     sizeof(ShortenContext),
 546     shorten_decode_init,
 547     NULL,
 548     shorten_decode_close,
 549     shorten_decode_frame,
 550     .flush= shorten_flush,
 551     .long_name= NULL_IF_CONFIG_SMALL("Shorten"),
 552 };