1/* 2 * TTA (The Lossless True Audio) decoder 3 * Copyright (c) 2006 Alex Beregszaszi 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/tta.c 24 * TTA (The Lossless True Audio) decoder 25 * (www.true-audio.com or tta.corecodec.org) 26 * @author Alex Beregszaszi 27 * 28 */ 29 30#define ALT_BITSTREAM_READER_LE 31//#define DEBUG 32#include <limits.h> 33#include "avcodec.h" 34#include "bitstream.h" 35 36#define FORMAT_INT 1 37#define FORMAT_FLOAT 3 38 39typedef struct TTAContext { 40 AVCodecContext *avctx; 41 GetBitContext gb; 42 43 int flags, channels, bps, is_float, data_length; 44 int frame_length, last_frame_length, total_frames; 45 46 int32_t *decode_buffer; 47} TTAContext; 48 49#if 0 50static inline int shift_1(int i) 51{ 52 if (i < 32) 53 return 1 << i; 54 else 55 return 0x80000000; // 16 << 31 56} 57 58static inline int shift_16(int i) 59{ 60 if (i < 28) 61 return 16 << i; 62 else 63 return 0x80000000; // 16 << 27 64} 65#else 66static const uint32_t shift_1[] = { 67 0x00000001, 0x00000002, 0x00000004, 0x00000008, 68 0x00000010, 0x00000020, 0x00000040, 0x00000080, 69 0x00000100, 0x00000200, 0x00000400, 0x00000800, 70 0x00001000, 0x00002000, 0x00004000, 0x00008000, 71 0x00010000, 0x00020000, 0x00040000, 0x00080000, 72 0x00100000, 0x00200000, 0x00400000, 0x00800000, 73 0x01000000, 0x02000000, 0x04000000, 0x08000000, 74 0x10000000, 0x20000000, 0x40000000, 0x80000000, 75 0x80000000, 0x80000000, 0x80000000, 0x80000000, 76 0x80000000, 0x80000000, 0x80000000, 0x80000000 77}; 78 79static const uint32_t * const shift_16 = shift_1 + 4; 80#endif 81 82#define MAX_ORDER 16 83typedef struct TTAFilter { 84 int32_t shift, round, error, mode; 85 int32_t qm[MAX_ORDER]; 86 int32_t dx[MAX_ORDER]; 87 int32_t dl[MAX_ORDER]; 88} TTAFilter; 89 90static const int32_t ttafilter_configs[4][2] = { 91 {10, 1}, 92 {9, 1}, 93 {10, 1}, 94 {12, 0} 95}; 96 97static void ttafilter_init(TTAFilter *c, int32_t shift, int32_t mode) { 98 memset(c, 0, sizeof(TTAFilter)); 99 c->shift = shift; 100 c->round = shift_1[shift-1]; 101// c->round = 1 << (shift - 1); 102 c->mode = mode; 103} 104 105// FIXME: copy paste from original 106static inline void memshl(register int32_t *a, register int32_t *b) { 107 *a++ = *b++; 108 *a++ = *b++; 109 *a++ = *b++; 110 *a++ = *b++; 111 *a++ = *b++; 112 *a++ = *b++; 113 *a++ = *b++; 114 *a = *b; 115} 116 117// FIXME: copy paste from original 118// mode=1 encoder, mode=0 decoder 119static inline void ttafilter_process(TTAFilter *c, int32_t *in, int32_t mode) { 120 register int32_t *dl = c->dl, *qm = c->qm, *dx = c->dx, sum = c->round; 121 122 if (!c->error) { 123 sum += *dl++ * *qm, qm++; 124 sum += *dl++ * *qm, qm++; 125 sum += *dl++ * *qm, qm++; 126 sum += *dl++ * *qm, qm++; 127 sum += *dl++ * *qm, qm++; 128 sum += *dl++ * *qm, qm++; 129 sum += *dl++ * *qm, qm++; 130 sum += *dl++ * *qm, qm++; 131 dx += 8; 132 } else if(c->error < 0) { 133 sum += *dl++ * (*qm -= *dx++), qm++; 134 sum += *dl++ * (*qm -= *dx++), qm++; 135 sum += *dl++ * (*qm -= *dx++), qm++; 136 sum += *dl++ * (*qm -= *dx++), qm++; 137 sum += *dl++ * (*qm -= *dx++), qm++; 138 sum += *dl++ * (*qm -= *dx++), qm++; 139 sum += *dl++ * (*qm -= *dx++), qm++; 140 sum += *dl++ * (*qm -= *dx++), qm++; 141 } else { 142 sum += *dl++ * (*qm += *dx++), qm++; 143 sum += *dl++ * (*qm += *dx++), qm++; 144 sum += *dl++ * (*qm += *dx++), qm++; 145 sum += *dl++ * (*qm += *dx++), qm++; 146 sum += *dl++ * (*qm += *dx++), qm++; 147 sum += *dl++ * (*qm += *dx++), qm++; 148 sum += *dl++ * (*qm += *dx++), qm++; 149 sum += *dl++ * (*qm += *dx++), qm++; 150 } 151 152 *(dx-0) = ((*(dl-1) >> 30) | 1) << 2; 153 *(dx-1) = ((*(dl-2) >> 30) | 1) << 1; 154 *(dx-2) = ((*(dl-3) >> 30) | 1) << 1; 155 *(dx-3) = ((*(dl-4) >> 30) | 1); 156 157 // compress 158 if (mode) { 159 *dl = *in; 160 *in -= (sum >> c->shift); 161 c->error = *in; 162 } else { 163 c->error = *in; 164 *in += (sum >> c->shift); 165 *dl = *in; 166 } 167 168 if (c->mode) { 169 *(dl-1) = *dl - *(dl-1); 170 *(dl-2) = *(dl-1) - *(dl-2); 171 *(dl-3) = *(dl-2) - *(dl-3); 172 } 173 174 memshl(c->dl, c->dl + 1); 175 memshl(c->dx, c->dx + 1); 176} 177 178typedef struct TTARice { 179 uint32_t k0, k1, sum0, sum1; 180} TTARice; 181 182static void rice_init(TTARice *c, uint32_t k0, uint32_t k1) 183{ 184 c->k0 = k0; 185 c->k1 = k1; 186 c->sum0 = shift_16[k0]; 187 c->sum1 = shift_16[k1]; 188} 189 190static int tta_get_unary(GetBitContext *gb) 191{ 192 int ret = 0; 193 194 // count ones 195 while(get_bits1(gb)) 196 ret++; 197 return ret; 198} 199 200static av_cold int tta_decode_init(AVCodecContext * avctx) 201{ 202 TTAContext *s = avctx->priv_data; 203 int i; 204 205 s->avctx = avctx; 206 207 // 30bytes includes a seektable with one frame 208 if (avctx->extradata_size < 30) 209 return -1; 210 211 init_get_bits(&s->gb, avctx->extradata, avctx->extradata_size); 212 if (show_bits_long(&s->gb, 32) == AV_RL32("TTA1")) 213 { 214 /* signature */ 215 skip_bits(&s->gb, 32); 216// if (get_bits_long(&s->gb, 32) != bswap_32(AV_RL32("TTA1"))) { 217// av_log(s->avctx, AV_LOG_ERROR, "Missing magic\n"); 218// return -1; 219// } 220 221 s->flags = get_bits(&s->gb, 16); 222 if (s->flags != 1 && s->flags != 3) 223 { 224 av_log(s->avctx, AV_LOG_ERROR, "Invalid flags\n"); 225 return -1; 226 } 227 s->is_float = (s->flags == FORMAT_FLOAT); 228 avctx->channels = s->channels = get_bits(&s->gb, 16); 229 avctx->bits_per_coded_sample = get_bits(&s->gb, 16); 230 s->bps = (avctx->bits_per_coded_sample + 7) / 8; 231 avctx->sample_rate = get_bits_long(&s->gb, 32); 232 if(avctx->sample_rate > 1000000){ //prevent FRAME_TIME * avctx->sample_rate from overflowing and sanity check 233 av_log(avctx, AV_LOG_ERROR, "sample_rate too large\n"); 234 return -1; 235 } 236 s->data_length = get_bits_long(&s->gb, 32); 237 skip_bits(&s->gb, 32); // CRC32 of header 238 239 if (s->is_float) 240 { 241 avctx->sample_fmt = SAMPLE_FMT_FLT; 242 av_log(s->avctx, AV_LOG_ERROR, "Unsupported sample format. Please contact the developers.\n"); 243 return -1; 244 } 245 else switch(s->bps) { 246// case 1: avctx->sample_fmt = SAMPLE_FMT_U8; break; 247 case 2: avctx->sample_fmt = SAMPLE_FMT_S16; break; 248// case 3: avctx->sample_fmt = SAMPLE_FMT_S24; break; 249 case 4: avctx->sample_fmt = SAMPLE_FMT_S32; break; 250 default: 251 av_log(s->avctx, AV_LOG_ERROR, "Invalid/unsupported sample format. Please contact the developers.\n"); 252 return -1; 253 } 254 255 // FIXME: horribly broken, but directly from reference source 256#define FRAME_TIME 1.04489795918367346939 257 s->frame_length = (int)(FRAME_TIME * avctx->sample_rate); 258 259 s->last_frame_length = s->data_length % s->frame_length; 260 s->total_frames = s->data_length / s->frame_length + 261 (s->last_frame_length ? 1 : 0); 262 263 av_log(s->avctx, AV_LOG_DEBUG, "flags: %x chans: %d bps: %d rate: %d block: %d\n", 264 s->flags, avctx->channels, avctx->bits_per_coded_sample, avctx->sample_rate, 265 avctx->block_align); 266 av_log(s->avctx, AV_LOG_DEBUG, "data_length: %d frame_length: %d last: %d total: %d\n", 267 s->data_length, s->frame_length, s->last_frame_length, s->total_frames); 268 269 // FIXME: seek table 270 for (i = 0; i < s->total_frames; i++) 271 skip_bits(&s->gb, 32); 272 skip_bits(&s->gb, 32); // CRC32 of seektable 273 274 if(s->frame_length >= UINT_MAX / (s->channels * sizeof(int32_t))){ 275 av_log(avctx, AV_LOG_ERROR, "frame_length too large\n"); 276 return -1; 277 } 278 279 s->decode_buffer = av_mallocz(sizeof(int32_t)*s->frame_length*s->channels); 280 } else { 281 av_log(avctx, AV_LOG_ERROR, "Wrong extradata present\n"); 282 return -1; 283 } 284 285 return 0; 286} 287 288static int tta_decode_frame(AVCodecContext *avctx, 289 void *data, int *data_size, 290 const uint8_t *buf, int buf_size) 291{ 292 TTAContext *s = avctx->priv_data; 293 int i; 294 295 init_get_bits(&s->gb, buf, buf_size*8); 296 { 297 int32_t predictors[s->channels]; 298 TTAFilter filters[s->channels]; 299 TTARice rices[s->channels]; 300 int cur_chan = 0, framelen = s->frame_length; 301 int32_t *p; 302 303 // FIXME: seeking 304 s->total_frames--; 305 if (!s->total_frames && s->last_frame_length) 306 framelen = s->last_frame_length; 307 308 // init per channel states 309 for (i = 0; i < s->channels; i++) { 310 predictors[i] = 0; 311 ttafilter_init(&(filters[i]), ttafilter_configs[s->bps-1][0], ttafilter_configs[s->bps-1][1]); 312 rice_init(&(rices[i]), 10, 10); 313 } 314 315 for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++) { 316 int32_t *predictor = &(predictors[cur_chan]); 317 TTAFilter *filter = &(filters[cur_chan]); 318 TTARice *rice = &(rices[cur_chan]); 319 uint32_t unary, depth, k; 320 int32_t value; 321 322 unary = tta_get_unary(&s->gb); 323 324 if (unary == 0) { 325 depth = 0; 326 k = rice->k0; 327 } else { 328 depth = 1; 329 k = rice->k1; 330 unary--; 331 } 332 333 if (k) 334 value = (unary << k) + get_bits(&s->gb, k); 335 else 336 value = unary; 337 338 // FIXME: copy paste from original 339 switch (depth) { 340 case 1: 341 rice->sum1 += value - (rice->sum1 >> 4); 342 if (rice->k1 > 0 && rice->sum1 < shift_16[rice->k1]) 343 rice->k1--; 344 else if(rice->sum1 > shift_16[rice->k1 + 1]) 345 rice->k1++; 346 value += shift_1[rice->k0]; 347 default: 348 rice->sum0 += value - (rice->sum0 >> 4); 349 if (rice->k0 > 0 && rice->sum0 < shift_16[rice->k0]) 350 rice->k0--; 351 else if(rice->sum0 > shift_16[rice->k0 + 1]) 352 rice->k0++; 353 } 354 355 // extract coded value 356#define UNFOLD(x) (((x)&1) ? (++(x)>>1) : (-(x)>>1)) 357 *p = UNFOLD(value); 358 359 // run hybrid filter 360 ttafilter_process(filter, p, 0); 361 362 // fixed order prediction 363#define PRED(x, k) (int32_t)((((uint64_t)x << k) - x) >> k) 364 switch (s->bps) { 365 case 1: *p += PRED(*predictor, 4); break; 366 case 2: 367 case 3: *p += PRED(*predictor, 5); break; 368 case 4: *p += *predictor; break; 369 } 370 *predictor = *p; 371 372#if 0 373 // extract 32bit float from last two int samples 374 if (s->is_float && ((p - data) & 1)) { 375 uint32_t neg = *p & 0x80000000; 376 uint32_t hi = *(p - 1); 377 uint32_t lo = abs(*p) - 1; 378 379 hi += (hi || lo) ? 0x3f80 : 0; 380 // SWAP16: swap all the 16 bits 381 *(p - 1) = (hi << 16) | SWAP16(lo) | neg; 382 } 383#endif 384 385 /*if ((get_bits_count(&s->gb)+7)/8 > buf_size) 386 { 387 av_log(NULL, AV_LOG_INFO, "overread!!\n"); 388 break; 389 }*/ 390 391 // flip channels 392 if (cur_chan < (s->channels-1)) 393 cur_chan++; 394 else { 395 // decorrelate in case of stereo integer 396 if (!s->is_float && (s->channels > 1)) { 397 int32_t *r = p - 1; 398 for (*p += *r / 2; r > p - s->channels; r--) 399 *r = *(r + 1) - *r; 400 } 401 cur_chan = 0; 402 } 403 } 404 405 skip_bits(&s->gb, 32); // frame crc 406 407 // convert to output buffer 408 switch(s->bps) { 409 case 2: { 410 uint16_t *samples = data; 411 for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++) { 412// *samples++ = (unsigned char)*p; 413// *samples++ = (unsigned char)(*p >> 8); 414 *samples++ = *p; 415 } 416 *data_size = (uint8_t *)samples - (uint8_t *)data; 417 break; 418 } 419 default: 420 av_log(s->avctx, AV_LOG_ERROR, "Error, only 16bit samples supported!\n"); 421 } 422 } 423 424// return get_bits_count(&s->gb)+7)/8; 425 return buf_size; 426} 427 428static av_cold int tta_decode_close(AVCodecContext *avctx) { 429 TTAContext *s = avctx->priv_data; 430 431 if (s->decode_buffer) 432 av_free(s->decode_buffer); 433 434 return 0; 435} 436 437AVCodec tta_decoder = { 438 "tta", 439 CODEC_TYPE_AUDIO, 440 CODEC_ID_TTA, 441 sizeof(TTAContext), 442 tta_decode_init, 443 NULL, 444 tta_decode_close, 445 tta_decode_frame, 446 .long_name = NULL_IF_CONFIG_SMALL("True Audio (TTA)"), 447}; 448