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tta.c
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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
24  * TTA (The Lossless True Audio) decoder
25  * @see http://www.true-audio.com/
26  * @see http://tta.corecodec.org/
27  * @author Alex Beregszaszi
28  */
29 
30 #define BITSTREAM_READER_LE
31 #include <limits.h>
32 #include "ttadata.h"
33 #include "ttadsp.h"
34 #include "avcodec.h"
35 #include "get_bits.h"
36 #include "thread.h"
37 #include "unary.h"
38 #include "internal.h"
39 #include "libavutil/crc.h"
40 #include "libavutil/intreadwrite.h"
41 #include "libavutil/opt.h"
42 
43 #define FORMAT_SIMPLE 1
44 #define FORMAT_ENCRYPTED 2
45 
46 typedef struct TTAContext {
47  AVClass *class;
49  const AVCRC *crc_table;
50 
52  unsigned data_length;
54 
56 
61 } TTAContext;
62 
63 static const int64_t tta_channel_layouts[7] = {
67  0,
69  AV_CH_LAYOUT_5POINT1_BACK|AV_CH_BACK_CENTER,
71 };
72 
73 static int tta_check_crc(TTAContext *s, const uint8_t *buf, int buf_size)
74 {
75  uint32_t crc, CRC;
76 
77  CRC = AV_RL32(buf + buf_size);
78  crc = av_crc(s->crc_table, 0xFFFFFFFFU, buf, buf_size);
79  if (CRC != (crc ^ 0xFFFFFFFFU)) {
80  av_log(s->avctx, AV_LOG_ERROR, "CRC error\n");
81  return AVERROR_INVALIDDATA;
82  }
83 
84  return 0;
85 }
86 
87 static uint64_t tta_check_crc64(uint8_t *pass)
88 {
89  uint64_t crc = UINT64_MAX, poly = 0x42F0E1EBA9EA3693U;
90  uint8_t *end = pass + strlen(pass);
91  int i;
92 
93  while (pass < end) {
94  crc ^= (uint64_t)*pass++ << 56;
95  for (i = 0; i < 8; i++)
96  crc = (crc << 1) ^ (poly & (((int64_t) crc) >> 63));
97  }
98 
99  return crc ^ UINT64_MAX;
100 }
101 
103 {
104  TTAContext *s = avctx->priv_data;
105 
106  if (s->bps < 3) {
108  if (!s->decode_buffer)
109  return AVERROR(ENOMEM);
110  } else
111  s->decode_buffer = NULL;
112  s->ch_ctx = av_malloc_array(avctx->channels, sizeof(*s->ch_ctx));
113  if (!s->ch_ctx) {
114  av_freep(&s->decode_buffer);
115  return AVERROR(ENOMEM);
116  }
117 
118  return 0;
119 }
120 
122 {
123  TTAContext *s = avctx->priv_data;
124  GetBitContext gb;
125  int total_frames;
126  int ret;
127 
128  s->avctx = avctx;
129 
130  // 30bytes includes TTA1 header
131  if (avctx->extradata_size < 22)
132  return AVERROR_INVALIDDATA;
133 
135  ret = init_get_bits8(&gb, avctx->extradata, avctx->extradata_size);
136  if (ret < 0)
137  return ret;
138 
139  if (show_bits_long(&gb, 32) == AV_RL32("TTA1")) {
140  /* signature */
141  skip_bits_long(&gb, 32);
142 
143  s->format = get_bits(&gb, 16);
144  if (s->format > 2) {
145  av_log(avctx, AV_LOG_ERROR, "Invalid format\n");
146  return AVERROR_INVALIDDATA;
147  }
148  if (s->format == FORMAT_ENCRYPTED) {
149  if (!s->pass) {
150  av_log(avctx, AV_LOG_ERROR, "Missing password for encrypted stream. Please use the -password option\n");
151  return AVERROR(EINVAL);
152  }
154  }
155  avctx->channels = s->channels = get_bits(&gb, 16);
156  if (s->channels > 1 && s->channels < 9)
158  avctx->bits_per_raw_sample = get_bits(&gb, 16);
159  s->bps = (avctx->bits_per_raw_sample + 7) / 8;
160  avctx->sample_rate = get_bits_long(&gb, 32);
161  s->data_length = get_bits_long(&gb, 32);
162  skip_bits_long(&gb, 32); // CRC32 of header
163 
164  if (s->channels == 0) {
165  av_log(avctx, AV_LOG_ERROR, "Invalid number of channels\n");
166  return AVERROR_INVALIDDATA;
167  } else if (avctx->sample_rate == 0) {
168  av_log(avctx, AV_LOG_ERROR, "Invalid samplerate\n");
169  return AVERROR_INVALIDDATA;
170  }
171 
172  switch(s->bps) {
173  case 1: avctx->sample_fmt = AV_SAMPLE_FMT_U8; break;
174  case 2:
175  avctx->sample_fmt = AV_SAMPLE_FMT_S16;
176  break;
177  case 3:
178  avctx->sample_fmt = AV_SAMPLE_FMT_S32;
179  break;
180  //case 4: avctx->sample_fmt = AV_SAMPLE_FMT_S32; break;
181  default:
182  av_log(avctx, AV_LOG_ERROR, "Invalid/unsupported sample format.\n");
183  return AVERROR_INVALIDDATA;
184  }
185 
186  // prevent overflow
187  if (avctx->sample_rate > 0x7FFFFFu) {
188  av_log(avctx, AV_LOG_ERROR, "sample_rate too large\n");
189  return AVERROR(EINVAL);
190  }
191  s->frame_length = 256 * avctx->sample_rate / 245;
192 
194  total_frames = s->data_length / s->frame_length +
195  (s->last_frame_length ? 1 : 0);
196 
197  av_log(avctx, AV_LOG_DEBUG, "format: %d chans: %d bps: %d rate: %d block: %d\n",
198  s->format, avctx->channels, avctx->bits_per_coded_sample, avctx->sample_rate,
199  avctx->block_align);
200  av_log(avctx, AV_LOG_DEBUG, "data_length: %d frame_length: %d last: %d total: %d\n",
201  s->data_length, s->frame_length, s->last_frame_length, total_frames);
202 
203  if(s->frame_length >= UINT_MAX / (s->channels * sizeof(int32_t))){
204  av_log(avctx, AV_LOG_ERROR, "frame_length too large\n");
205  return AVERROR_INVALIDDATA;
206  }
207  } else {
208  av_log(avctx, AV_LOG_ERROR, "Wrong extradata present\n");
209  return AVERROR_INVALIDDATA;
210  }
211 
212  ff_ttadsp_init(&s->dsp);
213 
214  return allocate_buffers(avctx);
215 }
216 
217 static int tta_decode_frame(AVCodecContext *avctx, void *data,
218  int *got_frame_ptr, AVPacket *avpkt)
219 {
220  AVFrame *frame = data;
221  ThreadFrame tframe = { .f = data };
222  const uint8_t *buf = avpkt->data;
223  int buf_size = avpkt->size;
224  TTAContext *s = avctx->priv_data;
225  GetBitContext gb;
226  int i, ret;
227  int cur_chan = 0, framelen = s->frame_length;
228  int32_t *p;
229 
230  if (avctx->err_recognition & AV_EF_CRCCHECK) {
231  if (buf_size < 4 ||
232  (tta_check_crc(s, buf, buf_size - 4) && avctx->err_recognition & AV_EF_EXPLODE))
233  return AVERROR_INVALIDDATA;
234  }
235 
236  if ((ret = init_get_bits8(&gb, avpkt->data, avpkt->size)) < 0)
237  return ret;
238 
239  /* get output buffer */
240  frame->nb_samples = framelen;
241  if ((ret = ff_thread_get_buffer(avctx, &tframe, 0)) < 0)
242  return ret;
243 
244  // decode directly to output buffer for 24-bit sample format
245  if (s->bps == 3)
246  s->decode_buffer = (int32_t *)frame->data[0];
247 
248  // init per channel states
249  for (i = 0; i < s->channels; i++) {
250  TTAFilter *filter = &s->ch_ctx[i].filter;
251  s->ch_ctx[i].predictor = 0;
253  if (s->format == FORMAT_ENCRYPTED) {
254  int i;
255  for (i = 0; i < 8; i++)
256  filter->qm[i] = sign_extend(s->crc_pass[i], 8);
257  }
258  ff_tta_rice_init(&s->ch_ctx[i].rice, 10, 10);
259  }
260 
261  i = 0;
262  for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++) {
263  int32_t *predictor = &s->ch_ctx[cur_chan].predictor;
264  TTAFilter *filter = &s->ch_ctx[cur_chan].filter;
265  TTARice *rice = &s->ch_ctx[cur_chan].rice;
266  uint32_t unary, depth, k;
267  int32_t value;
268 
269  unary = get_unary(&gb, 0, get_bits_left(&gb));
270 
271  if (unary == 0) {
272  depth = 0;
273  k = rice->k0;
274  } else {
275  depth = 1;
276  k = rice->k1;
277  unary--;
278  }
279 
280  if (get_bits_left(&gb) < k) {
281  ret = AVERROR_INVALIDDATA;
282  goto error;
283  }
284 
285  if (k) {
286  if (k > MIN_CACHE_BITS) {
287  ret = AVERROR_INVALIDDATA;
288  goto error;
289  }
290  value = (unary << k) + get_bits(&gb, k);
291  } else
292  value = unary;
293 
294  // FIXME: copy paste from original
295  switch (depth) {
296  case 1:
297  rice->sum1 += value - (rice->sum1 >> 4);
298  if (rice->k1 > 0 && rice->sum1 < ff_tta_shift_16[rice->k1])
299  rice->k1--;
300  else if(rice->sum1 > ff_tta_shift_16[rice->k1 + 1])
301  rice->k1++;
302  value += ff_tta_shift_1[rice->k0];
303  default:
304  rice->sum0 += value - (rice->sum0 >> 4);
305  if (rice->k0 > 0 && rice->sum0 < ff_tta_shift_16[rice->k0])
306  rice->k0--;
307  else if(rice->sum0 > ff_tta_shift_16[rice->k0 + 1])
308  rice->k0++;
309  }
310 
311  // extract coded value
312  *p = 1 + ((value >> 1) ^ ((value & 1) - 1));
313 
314  // run hybrid filter
315  s->dsp.ttafilter_process_dec(filter->qm, filter->dx, filter->dl, &filter->error, p,
316  filter->shift, filter->round);
317 
318  // fixed order prediction
319 #define PRED(x, k) (int32_t)((((uint64_t)(x) << (k)) - (x)) >> (k))
320  switch (s->bps) {
321  case 1: *p += PRED(*predictor, 4); break;
322  case 2:
323  case 3: *p += PRED(*predictor, 5); break;
324  case 4: *p += *predictor; break;
325  }
326  *predictor = *p;
327 
328  // flip channels
329  if (cur_chan < (s->channels-1))
330  cur_chan++;
331  else {
332  // decorrelate in case of multiple channels
333  if (s->channels > 1) {
334  int32_t *r = p - 1;
335  for (*p += *r / 2; r > p - s->channels; r--)
336  *r = *(r + 1) - *r;
337  }
338  cur_chan = 0;
339  i++;
340  // check for last frame
341  if (i == s->last_frame_length && get_bits_left(&gb) / 8 == 4) {
342  frame->nb_samples = framelen = s->last_frame_length;
343  break;
344  }
345  }
346  }
347 
348  align_get_bits(&gb);
349  if (get_bits_left(&gb) < 32) {
350  ret = AVERROR_INVALIDDATA;
351  goto error;
352  }
353  skip_bits_long(&gb, 32); // frame crc
354 
355  // convert to output buffer
356  switch (s->bps) {
357  case 1: {
358  uint8_t *samples = (uint8_t *)frame->data[0];
359  for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++)
360  *samples++ = *p + 0x80;
361  break;
362  }
363  case 2: {
364  int16_t *samples = (int16_t *)frame->data[0];
365  for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++)
366  *samples++ = *p;
367  break;
368  }
369  case 3: {
370  // shift samples for 24-bit sample format
371  int32_t *samples = (int32_t *)frame->data[0];
372  for (i = 0; i < framelen * s->channels; i++)
373  *samples++ <<= 8;
374  // reset decode buffer
375  s->decode_buffer = NULL;
376  break;
377  }
378  }
379 
380  *got_frame_ptr = 1;
381 
382  return buf_size;
383 error:
384  // reset decode buffer
385  if (s->bps == 3)
386  s->decode_buffer = NULL;
387  return ret;
388 }
389 
391 {
392  TTAContext *s = avctx->priv_data;
393  s->avctx = avctx;
394  return allocate_buffers(avctx);
395 }
396 
398  TTAContext *s = avctx->priv_data;
399 
400  if (s->bps < 3)
401  av_freep(&s->decode_buffer);
402  s->decode_buffer = NULL;
403  av_freep(&s->ch_ctx);
404 
405  return 0;
406 }
407 
408 #define OFFSET(x) offsetof(TTAContext, x)
409 #define DEC (AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM)
410 static const AVOption options[] = {
411  { "password", "Set decoding password", OFFSET(pass), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, DEC },
412  { NULL },
413 };
414 
415 static const AVClass tta_decoder_class = {
416  .class_name = "TTA Decoder",
417  .item_name = av_default_item_name,
418  .option = options,
419  .version = LIBAVUTIL_VERSION_INT,
420 };
421 
423  .name = "tta",
424  .long_name = NULL_IF_CONFIG_SMALL("TTA (True Audio)"),
425  .type = AVMEDIA_TYPE_AUDIO,
426  .id = AV_CODEC_ID_TTA,
427  .priv_data_size = sizeof(TTAContext),
429  .close = tta_decode_close,
432  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
433  .priv_class = &tta_decoder_class,
434 };