2 * TTA (The Lossless True Audio) decoder
3 * Copyright (c) 2006 Alex Beregszaszi
5 * This file is part of FFmpeg.
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.
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.
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
24 * TTA (The Lossless True Audio) decoder
25 * @see http://www.true-audio.com/
26 * @see http://tta.corecodec.org/
27 * @author Alex Beregszaszi
30 #define BITSTREAM_READER_LE
36 #include "libavutil/crc.h"
37 #include "libavutil/intreadwrite.h"
38 #include "libavutil/opt.h"
40 #define FORMAT_SIMPLE 1
41 #define FORMAT_ENCRYPTED 2
44 typedef struct TTAFilter {
45 int32_t shift, round, error;
46 int32_t qm[MAX_ORDER];
47 int32_t dx[MAX_ORDER];
48 int32_t dl[MAX_ORDER];
51 typedef struct TTARice {
52 uint32_t k0, k1, sum0, sum1;
55 typedef struct TTAChannel {
61 typedef struct TTAContext {
63 AVCodecContext *avctx;
65 const AVCRC *crc_table;
67 int format, channels, bps;
69 int frame_length, last_frame_length;
71 int32_t *decode_buffer;
78 static const uint32_t shift_1[] = {
79 0x00000001, 0x00000002, 0x00000004, 0x00000008,
80 0x00000010, 0x00000020, 0x00000040, 0x00000080,
81 0x00000100, 0x00000200, 0x00000400, 0x00000800,
82 0x00001000, 0x00002000, 0x00004000, 0x00008000,
83 0x00010000, 0x00020000, 0x00040000, 0x00080000,
84 0x00100000, 0x00200000, 0x00400000, 0x00800000,
85 0x01000000, 0x02000000, 0x04000000, 0x08000000,
86 0x10000000, 0x20000000, 0x40000000, 0x80000000,
87 0x80000000, 0x80000000, 0x80000000, 0x80000000,
88 0x80000000, 0x80000000, 0x80000000, 0x80000000
91 static const uint32_t * const shift_16 = shift_1 + 4;
93 static const int32_t ttafilter_configs[4] = {
100 static void ttafilter_init(TTAContext *s, TTAFilter *c, int32_t shift) {
101 memset(c, 0, sizeof(TTAFilter));
102 if (s->format == FORMAT_ENCRYPTED) {
104 for (i = 0; i < 8; i++)
105 c->qm[i] = sign_extend(s->crc_pass[i], 8);
108 c->round = shift_1[shift-1];
109 // c->round = 1 << (shift - 1);
112 static inline void ttafilter_process(TTAFilter *c, int32_t *in)
114 register int32_t *dl = c->dl, *qm = c->qm, *dx = c->dx, sum = c->round;
117 qm[0] -= dx[0]; qm[1] -= dx[1]; qm[2] -= dx[2]; qm[3] -= dx[3];
118 qm[4] -= dx[4]; qm[5] -= dx[5]; qm[6] -= dx[6]; qm[7] -= dx[7];
119 } else if (c->error > 0) {
120 qm[0] += dx[0]; qm[1] += dx[1]; qm[2] += dx[2]; qm[3] += dx[3];
121 qm[4] += dx[4]; qm[5] += dx[5]; qm[6] += dx[6]; qm[7] += dx[7];
124 sum += dl[0] * qm[0] + dl[1] * qm[1] + dl[2] * qm[2] + dl[3] * qm[3] +
125 dl[4] * qm[4] + dl[5] * qm[5] + dl[6] * qm[6] + dl[7] * qm[7];
127 dx[0] = dx[1]; dx[1] = dx[2]; dx[2] = dx[3]; dx[3] = dx[4];
128 dl[0] = dl[1]; dl[1] = dl[2]; dl[2] = dl[3]; dl[3] = dl[4];
130 dx[4] = ((dl[4] >> 30) | 1);
131 dx[5] = ((dl[5] >> 30) | 2) & ~1;
132 dx[6] = ((dl[6] >> 30) | 2) & ~1;
133 dx[7] = ((dl[7] >> 30) | 4) & ~3;
136 *in += (sum >> c->shift);
138 dl[4] = -dl[5]; dl[5] = -dl[6];
139 dl[6] = *in - dl[7]; dl[7] = *in;
140 dl[5] += dl[6]; dl[4] += dl[5];
143 static void rice_init(TTARice *c, uint32_t k0, uint32_t k1)
147 c->sum0 = shift_16[k0];
148 c->sum1 = shift_16[k1];
151 static int tta_get_unary(GetBitContext *gb)
156 while (get_bits_left(gb) > 0 && get_bits1(gb))
161 static const int64_t tta_channel_layouts[7] = {
163 AV_CH_LAYOUT_STEREO|AV_CH_LOW_FREQUENCY,
166 AV_CH_LAYOUT_5POINT1_BACK,
167 AV_CH_LAYOUT_5POINT1_BACK|AV_CH_BACK_CENTER,
168 AV_CH_LAYOUT_7POINT1_WIDE
171 static int tta_check_crc(TTAContext *s, const uint8_t *buf, int buf_size)
175 CRC = AV_RL32(buf + buf_size);
176 crc = av_crc(s->crc_table, 0xFFFFFFFFU, buf, buf_size);
177 if (CRC != (crc ^ 0xFFFFFFFFU)) {
178 av_log(s->avctx, AV_LOG_ERROR, "CRC error\n");
179 return AVERROR_INVALIDDATA;
185 static uint64_t tta_check_crc64(uint8_t *pass)
187 uint64_t crc = UINT64_MAX, poly = 0x42F0E1EBA9EA3693U;
188 uint8_t *end = pass + strlen(pass);
192 crc ^= (uint64_t)*pass++ << 56;
193 for (i = 0; i < 8; i++)
194 crc = (crc << 1) ^ (poly & (((int64_t) crc) >> 63));
197 return crc ^ UINT64_MAX;
200 static av_cold int tta_decode_init(AVCodecContext * avctx)
202 TTAContext *s = avctx->priv_data;
207 // 30bytes includes a seektable with one frame
208 if (avctx->extradata_size < 30)
209 return AVERROR_INVALIDDATA;
211 init_get_bits(&s->gb, avctx->extradata, avctx->extradata_size * 8);
212 if (show_bits_long(&s->gb, 32) == AV_RL32("TTA1"))
214 if (avctx->err_recognition & AV_EF_CRCCHECK) {
215 s->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE);
216 tta_check_crc(s, avctx->extradata, 18);
220 skip_bits_long(&s->gb, 32);
222 s->format = get_bits(&s->gb, 16);
224 av_log(avctx, AV_LOG_ERROR, "Invalid format\n");
225 return AVERROR_INVALIDDATA;
227 if (s->format == FORMAT_ENCRYPTED) {
229 av_log(avctx, AV_LOG_ERROR, "Missing password for encrypted stream. Please use the -password option\n");
230 return AVERROR(EINVAL);
232 AV_WL64(s->crc_pass, tta_check_crc64(s->pass));
234 avctx->channels = s->channels = get_bits(&s->gb, 16);
235 if (s->channels > 1 && s->channels < 9)
236 avctx->channel_layout = tta_channel_layouts[s->channels-2];
237 avctx->bits_per_raw_sample = get_bits(&s->gb, 16);
238 s->bps = (avctx->bits_per_raw_sample + 7) / 8;
239 avctx->sample_rate = get_bits_long(&s->gb, 32);
240 s->data_length = get_bits_long(&s->gb, 32);
241 skip_bits_long(&s->gb, 32); // CRC32 of header
243 if (s->channels == 0) {
244 av_log(avctx, AV_LOG_ERROR, "Invalid number of channels\n");
245 return AVERROR_INVALIDDATA;
246 } else if (avctx->sample_rate == 0) {
247 av_log(avctx, AV_LOG_ERROR, "Invalid samplerate\n");
248 return AVERROR_INVALIDDATA;
252 case 1: avctx->sample_fmt = AV_SAMPLE_FMT_U8; break;
254 avctx->sample_fmt = AV_SAMPLE_FMT_S16;
257 avctx->sample_fmt = AV_SAMPLE_FMT_S32;
259 //case 4: avctx->sample_fmt = AV_SAMPLE_FMT_S32; break;
261 av_log(avctx, AV_LOG_ERROR, "Invalid/unsupported sample format.\n");
262 return AVERROR_INVALIDDATA;
266 if (avctx->sample_rate > 0x7FFFFFu) {
267 av_log(avctx, AV_LOG_ERROR, "sample_rate too large\n");
268 return AVERROR(EINVAL);
270 s->frame_length = 256 * avctx->sample_rate / 245;
272 s->last_frame_length = s->data_length % s->frame_length;
273 total_frames = s->data_length / s->frame_length +
274 (s->last_frame_length ? 1 : 0);
276 av_log(avctx, AV_LOG_DEBUG, "format: %d chans: %d bps: %d rate: %d block: %d\n",
277 s->format, avctx->channels, avctx->bits_per_coded_sample, avctx->sample_rate,
279 av_log(avctx, AV_LOG_DEBUG, "data_length: %d frame_length: %d last: %d total: %d\n",
280 s->data_length, s->frame_length, s->last_frame_length, total_frames);
283 if (avctx->extradata_size <= 26 || total_frames > INT_MAX / 4 ||
284 avctx->extradata_size - 26 < total_frames * 4)
285 av_log(avctx, AV_LOG_WARNING, "Seek table missing or too small\n");
286 else if (avctx->err_recognition & AV_EF_CRCCHECK) {
287 if (tta_check_crc(s, avctx->extradata + 22, total_frames * 4))
288 return AVERROR_INVALIDDATA;
290 skip_bits_long(&s->gb, 32 * total_frames);
291 skip_bits_long(&s->gb, 32); // CRC32 of seektable
293 if(s->frame_length >= UINT_MAX / (s->channels * sizeof(int32_t))){
294 av_log(avctx, AV_LOG_ERROR, "frame_length too large\n");
295 return AVERROR_INVALIDDATA;
299 s->decode_buffer = av_mallocz(sizeof(int32_t)*s->frame_length*s->channels);
300 if (!s->decode_buffer)
301 return AVERROR(ENOMEM);
303 s->decode_buffer = NULL;
304 s->ch_ctx = av_malloc(avctx->channels * sizeof(*s->ch_ctx));
306 av_freep(&s->decode_buffer);
307 return AVERROR(ENOMEM);
310 av_log(avctx, AV_LOG_ERROR, "Wrong extradata present\n");
311 return AVERROR_INVALIDDATA;
317 static int tta_decode_frame(AVCodecContext *avctx, void *data,
318 int *got_frame_ptr, AVPacket *avpkt)
320 AVFrame *frame = data;
321 const uint8_t *buf = avpkt->data;
322 int buf_size = avpkt->size;
323 TTAContext *s = avctx->priv_data;
325 int cur_chan = 0, framelen = s->frame_length;
328 if (avctx->err_recognition & AV_EF_CRCCHECK) {
329 if (buf_size < 4 || tta_check_crc(s, buf, buf_size - 4))
330 return AVERROR_INVALIDDATA;
333 init_get_bits(&s->gb, buf, buf_size*8);
335 /* get output buffer */
336 frame->nb_samples = framelen;
337 if ((ret = ff_get_buffer(avctx, frame)) < 0) {
338 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
342 // decode directly to output buffer for 24-bit sample format
344 s->decode_buffer = (int32_t *)frame->data[0];
346 // init per channel states
347 for (i = 0; i < s->channels; i++) {
348 s->ch_ctx[i].predictor = 0;
349 ttafilter_init(s, &s->ch_ctx[i].filter, ttafilter_configs[s->bps-1]);
350 rice_init(&s->ch_ctx[i].rice, 10, 10);
354 for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++) {
355 int32_t *predictor = &s->ch_ctx[cur_chan].predictor;
356 TTAFilter *filter = &s->ch_ctx[cur_chan].filter;
357 TTARice *rice = &s->ch_ctx[cur_chan].rice;
358 uint32_t unary, depth, k;
361 unary = tta_get_unary(&s->gb);
372 if (get_bits_left(&s->gb) < k) {
373 ret = AVERROR_INVALIDDATA;
378 if (k > MIN_CACHE_BITS) {
379 ret = AVERROR_INVALIDDATA;
382 value = (unary << k) + get_bits(&s->gb, k);
386 // FIXME: copy paste from original
389 rice->sum1 += value - (rice->sum1 >> 4);
390 if (rice->k1 > 0 && rice->sum1 < shift_16[rice->k1])
392 else if(rice->sum1 > shift_16[rice->k1 + 1])
394 value += shift_1[rice->k0];
396 rice->sum0 += value - (rice->sum0 >> 4);
397 if (rice->k0 > 0 && rice->sum0 < shift_16[rice->k0])
399 else if(rice->sum0 > shift_16[rice->k0 + 1])
403 // extract coded value
404 *p = 1 + ((value >> 1) ^ ((value & 1) - 1));
407 ttafilter_process(filter, p);
409 // fixed order prediction
410 #define PRED(x, k) (int32_t)((((uint64_t)x << k) - x) >> k)
412 case 1: *p += PRED(*predictor, 4); break;
414 case 3: *p += PRED(*predictor, 5); break;
415 case 4: *p += *predictor; break;
420 if (cur_chan < (s->channels-1))
423 // decorrelate in case of multiple channels
424 if (s->channels > 1) {
426 for (*p += *r / 2; r > p - s->channels; r--)
431 // check for last frame
432 if (i == s->last_frame_length && get_bits_left(&s->gb) / 8 == 4) {
433 frame->nb_samples = framelen = s->last_frame_length;
439 align_get_bits(&s->gb);
440 if (get_bits_left(&s->gb) < 32) {
441 ret = AVERROR_INVALIDDATA;
444 skip_bits_long(&s->gb, 32); // frame crc
446 // convert to output buffer
449 uint8_t *samples = (uint8_t *)frame->data[0];
450 for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++)
451 *samples++ = *p + 0x80;
455 int16_t *samples = (int16_t *)frame->data[0];
456 for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++)
461 // shift samples for 24-bit sample format
462 int32_t *samples = (int32_t *)frame->data[0];
463 for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++)
465 // reset decode buffer
466 s->decode_buffer = NULL;
475 // reset decode buffer
477 s->decode_buffer = NULL;
481 static av_cold int tta_decode_close(AVCodecContext *avctx) {
482 TTAContext *s = avctx->priv_data;
485 av_free(s->decode_buffer);
486 s->decode_buffer = NULL;
487 av_freep(&s->ch_ctx);
492 #define OFFSET(x) offsetof(TTAContext, x)
493 #define DEC (AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM)
494 static const AVOption options[] = {
495 { "password", "Set decoding password", OFFSET(pass), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, DEC },
499 static const AVClass tta_decoder_class = {
500 .class_name = "TTA Decoder",
501 .item_name = av_default_item_name,
503 .version = LIBAVUTIL_VERSION_INT,
506 AVCodec ff_tta_decoder = {
508 .type = AVMEDIA_TYPE_AUDIO,
509 .id = AV_CODEC_ID_TTA,
510 .priv_data_size = sizeof(TTAContext),
511 .init = tta_decode_init,
512 .close = tta_decode_close,
513 .decode = tta_decode_frame,
514 .capabilities = CODEC_CAP_DR1,
515 .long_name = NULL_IF_CONFIG_SMALL("TTA (True Audio)"),
516 .priv_class = &tta_decoder_class,