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00029 #define DEBUG
00030 #include <limits.h>
00031 #include "avcodec.h"
00032 #include "bitstream.h"
00033 #include "golomb.h"
00034
00035 #define MAX_CHANNELS 8
00036 #define MAX_BLOCKSIZE 65535
00037
00038 #define OUT_BUFFER_SIZE 16384
00039
00040 #define ULONGSIZE 2
00041
00042 #define WAVE_FORMAT_PCM 0x0001
00043
00044 #define DEFAULT_BLOCK_SIZE 256
00045
00046 #define TYPESIZE 4
00047 #define CHANSIZE 0
00048 #define LPCQSIZE 2
00049 #define ENERGYSIZE 3
00050 #define BITSHIFTSIZE 2
00051
00052 #define TYPE_S16HL 3
00053 #define TYPE_S16LH 5
00054
00055 #define NWRAP 3
00056 #define NSKIPSIZE 1
00057
00058 #define LPCQUANT 5
00059 #define V2LPCQOFFSET (1 << LPCQUANT)
00060
00061 #define FNSIZE 2
00062 #define FN_DIFF0 0
00063 #define FN_DIFF1 1
00064 #define FN_DIFF2 2
00065 #define FN_DIFF3 3
00066 #define FN_QUIT 4
00067 #define FN_BLOCKSIZE 5
00068 #define FN_BITSHIFT 6
00069 #define FN_QLPC 7
00070 #define FN_ZERO 8
00071 #define FN_VERBATIM 9
00072
00073 #define VERBATIM_CKSIZE_SIZE 5
00074 #define VERBATIM_BYTE_SIZE 8
00075 #define CANONICAL_HEADER_SIZE 44
00076
00077 typedef struct ShortenContext {
00078 AVCodecContext *avctx;
00079 GetBitContext gb;
00080
00081 int min_framesize, max_framesize;
00082 int channels;
00083
00084 int32_t *decoded[MAX_CHANNELS];
00085 int32_t *decoded_base[MAX_CHANNELS];
00086 int32_t *offset[MAX_CHANNELS];
00087 uint8_t *bitstream;
00088 int bitstream_size;
00089 int bitstream_index;
00090 unsigned int allocated_bitstream_size;
00091 int header_size;
00092 uint8_t header[OUT_BUFFER_SIZE];
00093 int version;
00094 int cur_chan;
00095 int bitshift;
00096 int nmean;
00097 int internal_ftype;
00098 int nwrap;
00099 int blocksize;
00100 int bitindex;
00101 int32_t lpcqoffset;
00102 } ShortenContext;
00103
00104 static av_cold int shorten_decode_init(AVCodecContext * avctx)
00105 {
00106 ShortenContext *s = avctx->priv_data;
00107 s->avctx = avctx;
00108 avctx->sample_fmt = SAMPLE_FMT_S16;
00109
00110 return 0;
00111 }
00112
00113 static int allocate_buffers(ShortenContext *s)
00114 {
00115 int i, chan;
00116 void *tmp_ptr;
00117
00118 for (chan=0; chan<s->channels; chan++) {
00119 if(FFMAX(1, s->nmean) >= UINT_MAX/sizeof(int32_t)){
00120 av_log(s->avctx, AV_LOG_ERROR, "nmean too large\n");
00121 return -1;
00122 }
00123 if(s->blocksize + s->nwrap >= UINT_MAX/sizeof(int32_t) || s->blocksize + s->nwrap <= (unsigned)s->nwrap){
00124 av_log(s->avctx, AV_LOG_ERROR, "s->blocksize + s->nwrap too large\n");
00125 return -1;
00126 }
00127
00128 tmp_ptr = av_realloc(s->offset[chan], sizeof(int32_t)*FFMAX(1, s->nmean));
00129 if (!tmp_ptr)
00130 return AVERROR(ENOMEM);
00131 s->offset[chan] = tmp_ptr;
00132
00133 tmp_ptr = av_realloc(s->decoded_base[chan], (s->blocksize + s->nwrap) *
00134 sizeof(s->decoded_base[0][0]));
00135 if (!tmp_ptr)
00136 return AVERROR(ENOMEM);
00137 s->decoded_base[chan] = tmp_ptr;
00138 for (i=0; i<s->nwrap; i++)
00139 s->decoded_base[chan][i] = 0;
00140 s->decoded[chan] = s->decoded_base[chan] + s->nwrap;
00141 }
00142 return 0;
00143 }
00144
00145
00146 static inline unsigned int get_uint(ShortenContext *s, int k)
00147 {
00148 if (s->version != 0)
00149 k = get_ur_golomb_shorten(&s->gb, ULONGSIZE);
00150 return get_ur_golomb_shorten(&s->gb, k);
00151 }
00152
00153
00154 static void fix_bitshift(ShortenContext *s, int32_t *buffer)
00155 {
00156 int i;
00157
00158 if (s->bitshift != 0)
00159 for (i = 0; i < s->blocksize; i++)
00160 buffer[s->nwrap + i] <<= s->bitshift;
00161 }
00162
00163
00164 static void init_offset(ShortenContext *s)
00165 {
00166 int32_t mean = 0;
00167 int chan, i;
00168 int nblock = FFMAX(1, s->nmean);
00169
00170 switch (s->internal_ftype)
00171 {
00172 case TYPE_S16HL:
00173 case TYPE_S16LH:
00174 mean = 0;
00175 break;
00176 default:
00177 av_log(s->avctx, AV_LOG_ERROR, "unknown audio type");
00178 abort();
00179 }
00180
00181 for (chan = 0; chan < s->channels; chan++)
00182 for (i = 0; i < nblock; i++)
00183 s->offset[chan][i] = mean;
00184 }
00185
00186 static inline int get_le32(GetBitContext *gb)
00187 {
00188 return bswap_32(get_bits_long(gb, 32));
00189 }
00190
00191 static inline short get_le16(GetBitContext *gb)
00192 {
00193 return bswap_16(get_bits_long(gb, 16));
00194 }
00195
00196 static int decode_wave_header(AVCodecContext *avctx, uint8_t *header, int header_size)
00197 {
00198 GetBitContext hb;
00199 int len;
00200 int chunk_size;
00201 short wave_format;
00202
00203 init_get_bits(&hb, header, header_size*8);
00204 if (get_le32(&hb) != MKTAG('R','I','F','F')) {
00205 av_log(avctx, AV_LOG_ERROR, "missing RIFF tag\n");
00206 return -1;
00207 }
00208
00209 chunk_size = get_le32(&hb);
00210
00211 if (get_le32(&hb) != MKTAG('W','A','V','E')) {
00212 av_log(avctx, AV_LOG_ERROR, "missing WAVE tag\n");
00213 return -1;
00214 }
00215
00216 while (get_le32(&hb) != MKTAG('f','m','t',' ')) {
00217 len = get_le32(&hb);
00218 skip_bits(&hb, 8*len);
00219 }
00220 len = get_le32(&hb);
00221
00222 if (len < 16) {
00223 av_log(avctx, AV_LOG_ERROR, "fmt chunk was too short\n");
00224 return -1;
00225 }
00226
00227 wave_format = get_le16(&hb);
00228
00229 switch (wave_format) {
00230 case WAVE_FORMAT_PCM:
00231 break;
00232 default:
00233 av_log(avctx, AV_LOG_ERROR, "unsupported wave format\n");
00234 return -1;
00235 }
00236
00237 avctx->channels = get_le16(&hb);
00238 avctx->sample_rate = get_le32(&hb);
00239 avctx->bit_rate = get_le32(&hb) * 8;
00240 avctx->block_align = get_le16(&hb);
00241 avctx->bits_per_coded_sample = get_le16(&hb);
00242
00243 if (avctx->bits_per_coded_sample != 16) {
00244 av_log(avctx, AV_LOG_ERROR, "unsupported number of bits per sample\n");
00245 return -1;
00246 }
00247
00248 len -= 16;
00249 if (len > 0)
00250 av_log(avctx, AV_LOG_INFO, "%d header bytes unparsed\n", len);
00251
00252 return 0;
00253 }
00254
00255 static int16_t * interleave_buffer(int16_t *samples, int nchan, int blocksize, int32_t **buffer) {
00256 int i, chan;
00257 for (i=0; i<blocksize; i++)
00258 for (chan=0; chan < nchan; chan++)
00259 *samples++ = FFMIN(buffer[chan][i], 32768);
00260 return samples;
00261 }
00262
00263 static void decode_subframe_lpc(ShortenContext *s, int channel, int residual_size, int pred_order)
00264 {
00265 int sum, i, j;
00266 int coeffs[pred_order];
00267
00268 for (i=0; i<pred_order; i++)
00269 coeffs[i] = get_sr_golomb_shorten(&s->gb, LPCQUANT);
00270
00271 for (i=0; i < s->blocksize; i++) {
00272 sum = s->lpcqoffset;
00273 for (j=0; j<pred_order; j++)
00274 sum += coeffs[j] * s->decoded[channel][i-j-1];
00275 s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + (sum >> LPCQUANT);
00276 }
00277 }
00278
00279
00280 static int shorten_decode_frame(AVCodecContext *avctx,
00281 void *data, int *data_size,
00282 const uint8_t *buf, int buf_size)
00283 {
00284 ShortenContext *s = avctx->priv_data;
00285 int i, input_buf_size = 0;
00286 int16_t *samples = data;
00287 if(s->max_framesize == 0){
00288 void *tmp_ptr;
00289 s->max_framesize= 1024;
00290 tmp_ptr = av_fast_realloc(s->bitstream, &s->allocated_bitstream_size,
00291 s->max_framesize);
00292 if (!tmp_ptr) {
00293 av_log(avctx, AV_LOG_ERROR, "error allocating bitstream buffer\n");
00294 return AVERROR(ENOMEM);
00295 }
00296 s->bitstream = tmp_ptr;
00297 }
00298
00299 if(1 && s->max_framesize){
00300 buf_size= FFMIN(buf_size, s->max_framesize - s->bitstream_size);
00301 input_buf_size= buf_size;
00302
00303 if(s->bitstream_index + s->bitstream_size + buf_size > s->allocated_bitstream_size){
00304
00305 memmove(s->bitstream, &s->bitstream[s->bitstream_index], s->bitstream_size);
00306 s->bitstream_index=0;
00307 }
00308 memcpy(&s->bitstream[s->bitstream_index + s->bitstream_size], buf, buf_size);
00309 buf= &s->bitstream[s->bitstream_index];
00310 buf_size += s->bitstream_size;
00311 s->bitstream_size= buf_size;
00312
00313 if(buf_size < s->max_framesize){
00314
00315 *data_size = 0;
00316 return input_buf_size;
00317 }
00318 }
00319 init_get_bits(&s->gb, buf, buf_size*8);
00320 skip_bits(&s->gb, s->bitindex);
00321 if (!s->blocksize)
00322 {
00323 int maxnlpc = 0;
00324
00325 if (get_bits_long(&s->gb, 32) != AV_RB32("ajkg")) {
00326 av_log(s->avctx, AV_LOG_ERROR, "missing shorten magic 'ajkg'\n");
00327 return -1;
00328 }
00329
00330 s->lpcqoffset = 0;
00331 s->blocksize = DEFAULT_BLOCK_SIZE;
00332 s->channels = 1;
00333 s->nmean = -1;
00334 s->version = get_bits(&s->gb, 8);
00335 s->internal_ftype = get_uint(s, TYPESIZE);
00336
00337 s->channels = get_uint(s, CHANSIZE);
00338 if (s->channels > MAX_CHANNELS) {
00339 av_log(s->avctx, AV_LOG_ERROR, "too many channels: %d\n", s->channels);
00340 return -1;
00341 }
00342
00343
00344 if (s->version > 0) {
00345 int skip_bytes;
00346 s->blocksize = get_uint(s, av_log2(DEFAULT_BLOCK_SIZE));
00347 maxnlpc = get_uint(s, LPCQSIZE);
00348 s->nmean = get_uint(s, 0);
00349
00350 skip_bytes = get_uint(s, NSKIPSIZE);
00351 for (i=0; i<skip_bytes; i++) {
00352 skip_bits(&s->gb, 8);
00353 }
00354 }
00355 s->nwrap = FFMAX(NWRAP, maxnlpc);
00356
00357 if (allocate_buffers(s))
00358 return -1;
00359
00360 init_offset(s);
00361
00362 if (s->version > 1)
00363 s->lpcqoffset = V2LPCQOFFSET;
00364
00365 if (get_ur_golomb_shorten(&s->gb, FNSIZE) != FN_VERBATIM) {
00366 av_log(s->avctx, AV_LOG_ERROR, "missing verbatim section at beginning of stream\n");
00367 return -1;
00368 }
00369
00370 s->header_size = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);
00371 if (s->header_size >= OUT_BUFFER_SIZE || s->header_size < CANONICAL_HEADER_SIZE) {
00372 av_log(s->avctx, AV_LOG_ERROR, "header is wrong size: %d\n", s->header_size);
00373 return -1;
00374 }
00375
00376 for (i=0; i<s->header_size; i++)
00377 s->header[i] = (char)get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);
00378
00379 if (decode_wave_header(avctx, s->header, s->header_size) < 0)
00380 return -1;
00381
00382 s->cur_chan = 0;
00383 s->bitshift = 0;
00384 }
00385 else
00386 {
00387 int cmd;
00388 int len;
00389 cmd = get_ur_golomb_shorten(&s->gb, FNSIZE);
00390 switch (cmd) {
00391 case FN_ZERO:
00392 case FN_DIFF0:
00393 case FN_DIFF1:
00394 case FN_DIFF2:
00395 case FN_DIFF3:
00396 case FN_QLPC:
00397 {
00398 int residual_size = 0;
00399 int channel = s->cur_chan;
00400 int32_t coffset;
00401 if (cmd != FN_ZERO) {
00402 residual_size = get_ur_golomb_shorten(&s->gb, ENERGYSIZE);
00403
00404 if (s->version == 0)
00405 residual_size--;
00406 }
00407
00408 if (s->nmean == 0)
00409 coffset = s->offset[channel][0];
00410 else {
00411 int32_t sum = (s->version < 2) ? 0 : s->nmean / 2;
00412 for (i=0; i<s->nmean; i++)
00413 sum += s->offset[channel][i];
00414 coffset = sum / s->nmean;
00415 if (s->version >= 2)
00416 coffset >>= FFMIN(1, s->bitshift);
00417 }
00418 switch (cmd) {
00419 case FN_ZERO:
00420 for (i=0; i<s->blocksize; i++)
00421 s->decoded[channel][i] = 0;
00422 break;
00423 case FN_DIFF0:
00424 for (i=0; i<s->blocksize; i++)
00425 s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + coffset;
00426 break;
00427 case FN_DIFF1:
00428 for (i=0; i<s->blocksize; i++)
00429 s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + s->decoded[channel][i - 1];
00430 break;
00431 case FN_DIFF2:
00432 for (i=0; i<s->blocksize; i++)
00433 s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + 2*s->decoded[channel][i-1]
00434 - s->decoded[channel][i-2];
00435 break;
00436 case FN_DIFF3:
00437 for (i=0; i<s->blocksize; i++)
00438 s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + 3*s->decoded[channel][i-1]
00439 - 3*s->decoded[channel][i-2]
00440 + s->decoded[channel][i-3];
00441 break;
00442 case FN_QLPC:
00443 {
00444 int pred_order = get_ur_golomb_shorten(&s->gb, LPCQSIZE);
00445 for (i=0; i<pred_order; i++)
00446 s->decoded[channel][i - pred_order] -= coffset;
00447 decode_subframe_lpc(s, channel, residual_size, pred_order);
00448 if (coffset != 0)
00449 for (i=0; i < s->blocksize; i++)
00450 s->decoded[channel][i] += coffset;
00451 }
00452 }
00453 if (s->nmean > 0) {
00454 int32_t sum = (s->version < 2) ? 0 : s->blocksize / 2;
00455 for (i=0; i<s->blocksize; i++)
00456 sum += s->decoded[channel][i];
00457
00458 for (i=1; i<s->nmean; i++)
00459 s->offset[channel][i-1] = s->offset[channel][i];
00460
00461 if (s->version < 2)
00462 s->offset[channel][s->nmean - 1] = sum / s->blocksize;
00463 else
00464 s->offset[channel][s->nmean - 1] = (sum / s->blocksize) << s->bitshift;
00465 }
00466 for (i=-s->nwrap; i<0; i++)
00467 s->decoded[channel][i] = s->decoded[channel][i + s->blocksize];
00468
00469 fix_bitshift(s, s->decoded[channel]);
00470
00471 s->cur_chan++;
00472 if (s->cur_chan == s->channels) {
00473 samples = interleave_buffer(samples, s->channels, s->blocksize, s->decoded);
00474 s->cur_chan = 0;
00475 goto frame_done;
00476 }
00477 break;
00478 }
00479 break;
00480 case FN_VERBATIM:
00481 len = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);
00482 while (len--) {
00483 get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);
00484 }
00485 break;
00486 case FN_BITSHIFT:
00487 s->bitshift = get_ur_golomb_shorten(&s->gb, BITSHIFTSIZE);
00488 break;
00489 case FN_BLOCKSIZE:
00490 s->blocksize = get_uint(s, av_log2(s->blocksize));
00491 break;
00492 case FN_QUIT:
00493 *data_size = 0;
00494 return buf_size;
00495 break;
00496 default:
00497 av_log(avctx, AV_LOG_ERROR, "unknown shorten function %d\n", cmd);
00498 return -1;
00499 break;
00500 }
00501 }
00502 frame_done:
00503 *data_size = (int8_t *)samples - (int8_t *)data;
00504
00505
00506 s->bitindex = get_bits_count(&s->gb) - 8*((get_bits_count(&s->gb))/8);
00507 i= (get_bits_count(&s->gb))/8;
00508 if (i > buf_size) {
00509 av_log(s->avctx, AV_LOG_ERROR, "overread: %d\n", i - buf_size);
00510 s->bitstream_size=0;
00511 s->bitstream_index=0;
00512 return -1;
00513 }
00514 if (s->bitstream_size) {
00515 s->bitstream_index += i;
00516 s->bitstream_size -= i;
00517 return input_buf_size;
00518 } else
00519 return i;
00520 }
00521
00522 static av_cold int shorten_decode_close(AVCodecContext *avctx)
00523 {
00524 ShortenContext *s = avctx->priv_data;
00525 int i;
00526
00527 for (i = 0; i < s->channels; i++) {
00528 s->decoded[i] = NULL;
00529 av_freep(&s->decoded_base[i]);
00530 av_freep(&s->offset[i]);
00531 }
00532 av_freep(&s->bitstream);
00533 return 0;
00534 }
00535
00536 static void shorten_flush(AVCodecContext *avctx){
00537 ShortenContext *s = avctx->priv_data;
00538
00539 s->bitstream_size=
00540 s->bitstream_index= 0;
00541 }
00542
00543 AVCodec shorten_decoder = {
00544 "shorten",
00545 CODEC_TYPE_AUDIO,
00546 CODEC_ID_SHORTEN,
00547 sizeof(ShortenContext),
00548 shorten_decode_init,
00549 NULL,
00550 shorten_decode_close,
00551 shorten_decode_frame,
00552 .flush= shorten_flush,
00553 .long_name= NULL_IF_CONFIG_SMALL("Shorten"),
00554 };