pcm.c
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1 /*
2  * PCM codecs
3  * Copyright (c) 2001 Fabrice Bellard
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 
27 #include "libavutil/attributes.h"
28 #include "avcodec.h"
29 #include "bytestream.h"
30 #include "internal.h"
31 #include "mathops.h"
32 #include "pcm_tablegen.h"
33 
35 {
36  avctx->frame_size = 0;
37  switch (avctx->codec->id) {
40  break;
43  break;
44  default:
45  break;
46  }
47 
49  avctx->block_align = avctx->channels * avctx->bits_per_coded_sample / 8;
50  avctx->bit_rate = avctx->block_align * avctx->sample_rate * 8;
52  if (!avctx->coded_frame)
53  return AVERROR(ENOMEM);
54 
55  return 0;
56 }
57 
59 {
60  av_freep(&avctx->coded_frame);
61 
62  return 0;
63 }
64 
75 #define ENCODE(type, endian, src, dst, n, shift, offset) \
76  samples_ ## type = (const type *) src; \
77  for (; n > 0; n--) { \
78  register type v = (*samples_ ## type++ >> shift) + offset; \
79  bytestream_put_ ## endian(&dst, v); \
80  }
81 
82 static int pcm_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
83  const AVFrame *frame, int *got_packet_ptr)
84 {
85  int n, sample_size, v, ret;
86  const short *samples;
87  unsigned char *dst;
88  const uint8_t *srcu8;
89  const int16_t *samples_int16_t;
90  const int32_t *samples_int32_t;
91  const int64_t *samples_int64_t;
92  const uint16_t *samples_uint16_t;
93  const uint32_t *samples_uint32_t;
94 
95  sample_size = av_get_bits_per_sample(avctx->codec->id) / 8;
96  n = frame->nb_samples * avctx->channels;
97  samples = (const short *)frame->data[0];
98 
99  if ((ret = ff_alloc_packet(avpkt, n * sample_size))) {
100  av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
101  return ret;
102  }
103  dst = avpkt->data;
104 
105  switch (avctx->codec->id) {
107  ENCODE(uint32_t, le32, samples, dst, n, 0, 0x80000000)
108  break;
110  ENCODE(uint32_t, be32, samples, dst, n, 0, 0x80000000)
111  break;
113  ENCODE(int32_t, le24, samples, dst, n, 8, 0)
114  break;
116  ENCODE(int32_t, be24, samples, dst, n, 8, 0)
117  break;
119  ENCODE(uint32_t, le24, samples, dst, n, 8, 0x800000)
120  break;
122  ENCODE(uint32_t, be24, samples, dst, n, 8, 0x800000)
123  break;
125  for (; n > 0; n--) {
126  uint32_t tmp = ff_reverse[(*samples >> 8) & 0xff] +
127  (ff_reverse[*samples & 0xff] << 8);
128  tmp <<= 4; // sync flags would go here
129  bytestream_put_be24(&dst, tmp);
130  samples++;
131  }
132  break;
134  ENCODE(uint16_t, le16, samples, dst, n, 0, 0x8000)
135  break;
137  ENCODE(uint16_t, be16, samples, dst, n, 0, 0x8000)
138  break;
139  case AV_CODEC_ID_PCM_S8:
140  srcu8 = frame->data[0];
141  for (; n > 0; n--) {
142  v = *srcu8++;
143  *dst++ = v - 128;
144  }
145  break;
146 #if HAVE_BIGENDIAN
148  ENCODE(int64_t, le64, samples, dst, n, 0, 0)
149  break;
152  ENCODE(int32_t, le32, samples, dst, n, 0, 0)
153  break;
155  ENCODE(int16_t, le16, samples, dst, n, 0, 0)
156  break;
161 #else
163  ENCODE(int64_t, be64, samples, dst, n, 0, 0)
164  break;
167  ENCODE(int32_t, be32, samples, dst, n, 0, 0)
168  break;
170  ENCODE(int16_t, be16, samples, dst, n, 0, 0)
171  break;
176 #endif /* HAVE_BIGENDIAN */
177  case AV_CODEC_ID_PCM_U8:
178  memcpy(dst, samples, n * sample_size);
179  dst += n * sample_size;
180  break;
182  for (; n > 0; n--) {
183  v = *samples++;
184  *dst++ = linear_to_alaw[(v + 32768) >> 2];
185  }
186  break;
188  for (; n > 0; n--) {
189  v = *samples++;
190  *dst++ = linear_to_ulaw[(v + 32768) >> 2];
191  }
192  break;
193  default:
194  return -1;
195  }
196 
197  *got_packet_ptr = 1;
198  return 0;
199 }
200 
201 typedef struct PCMDecode {
203  short table[256];
204 } PCMDecode;
205 
207 {
208  PCMDecode *s = avctx->priv_data;
209  int i;
210 
211  if (avctx->channels <= 0) {
212  av_log(avctx, AV_LOG_ERROR, "PCM channels out of bounds\n");
213  return AVERROR(EINVAL);
214  }
215 
216  switch (avctx->codec->id) {
218  for (i = 0; i < 256; i++)
219  s->table[i] = alaw2linear(i);
220  break;
222  for (i = 0; i < 256; i++)
223  s->table[i] = ulaw2linear(i);
224  break;
225  default:
226  break;
227  }
228 
229  avctx->sample_fmt = avctx->codec->sample_fmts[0];
230 
231  if (avctx->sample_fmt == AV_SAMPLE_FMT_S32)
233 
235  avctx->coded_frame = &s->frame;
236 
237  return 0;
238 }
239 
250 #define DECODE(size, endian, src, dst, n, shift, offset) \
251  for (; n > 0; n--) { \
252  uint ## size ## _t v = bytestream_get_ ## endian(&src); \
253  AV_WN ## size ## A(dst, (v - offset) << shift); \
254  dst += size / 8; \
255  }
256 
257 static int pcm_decode_frame(AVCodecContext *avctx, void *data,
258  int *got_frame_ptr, AVPacket *avpkt)
259 {
260  const uint8_t *src = avpkt->data;
261  int buf_size = avpkt->size;
262  PCMDecode *s = avctx->priv_data;
263  int sample_size, c, n, ret, samples_per_block;
264  uint8_t *samples;
265  int32_t *dst_int32_t;
266 
267  sample_size = av_get_bits_per_sample(avctx->codec_id) / 8;
268 
269  /* av_get_bits_per_sample returns 0 for AV_CODEC_ID_PCM_DVD */
270  samples_per_block = 1;
271  if (avctx->codec->id == AV_CODEC_ID_PCM_DVD) {
272  if (avctx->bits_per_coded_sample != 20 &&
273  avctx->bits_per_coded_sample != 24) {
274  av_log(avctx, AV_LOG_ERROR, "PCM DVD unsupported sample depth\n");
275  return AVERROR(EINVAL);
276  }
277  /* 2 samples are interleaved per block in PCM_DVD */
278  samples_per_block = 2;
279  sample_size = avctx->bits_per_coded_sample * 2 / 8;
280  } else if (avctx->codec_id == AV_CODEC_ID_PCM_LXF) {
281  /* we process 40-bit blocks per channel for LXF */
282  samples_per_block = 2;
283  sample_size = 5;
284  }
285 
286  if (sample_size == 0) {
287  av_log(avctx, AV_LOG_ERROR, "Invalid sample_size\n");
288  return AVERROR(EINVAL);
289  }
290 
291  n = avctx->channels * sample_size;
292 
293  if (n && buf_size % n) {
294  if (buf_size < n) {
295  av_log(avctx, AV_LOG_ERROR, "invalid PCM packet\n");
296  return -1;
297  } else
298  buf_size -= buf_size % n;
299  }
300 
301  n = buf_size / sample_size;
302 
303  /* get output buffer */
304  s->frame.nb_samples = n * samples_per_block / avctx->channels;
305  if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {
306  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
307  return ret;
308  }
309  samples = s->frame.data[0];
310 
311  switch (avctx->codec->id) {
313  DECODE(32, le32, src, samples, n, 0, 0x80000000)
314  break;
316  DECODE(32, be32, src, samples, n, 0, 0x80000000)
317  break;
319  DECODE(32, le24, src, samples, n, 8, 0)
320  break;
322  DECODE(32, be24, src, samples, n, 8, 0)
323  break;
325  DECODE(32, le24, src, samples, n, 8, 0x800000)
326  break;
328  DECODE(32, be24, src, samples, n, 8, 0x800000)
329  break;
331  for (; n > 0; n--) {
332  uint32_t v = bytestream_get_be24(&src);
333  v >>= 4; // sync flags are here
334  AV_WN16A(samples, ff_reverse[(v >> 8) & 0xff] +
335  (ff_reverse[v & 0xff] << 8));
336  samples += 2;
337  }
338  break;
340  {
341  int av_unused n2;
342  n /= avctx->channels;
343  for (c = 0; c < avctx->channels; c++) {
344  samples = s->frame.extended_data[c];
345 #if HAVE_BIGENDIAN
346  n2 = n;
347  DECODE(16, le16, src, samples, n2, 0, 0)
348 #else
349  memcpy(samples, src, n * 2);
350  src += n * 2;
351 #endif
352  }
353  break;
354  }
356  DECODE(16, le16, src, samples, n, 0, 0x8000)
357  break;
359  DECODE(16, be16, src, samples, n, 0, 0x8000)
360  break;
361  case AV_CODEC_ID_PCM_S8:
362  for (; n > 0; n--)
363  *samples++ = *src++ + 128;
364  break;
365 #if HAVE_BIGENDIAN
367  DECODE(64, le64, src, samples, n, 0, 0)
368  break;
371  DECODE(32, le32, src, samples, n, 0, 0)
372  break;
374  DECODE(16, le16, src, samples, n, 0, 0)
375  break;
380 #else
382  DECODE(64, be64, src, samples, n, 0, 0)
383  break;
386  DECODE(32, be32, src, samples, n, 0, 0)
387  break;
389  DECODE(16, be16, src, samples, n, 0, 0)
390  break;
395 #endif /* HAVE_BIGENDIAN */
396  case AV_CODEC_ID_PCM_U8:
397  memcpy(samples, src, n * sample_size);
398  break;
400  for (; n > 0; n--) {
401  int v = *src++;
402  if (v < 128)
403  v = 128 - v;
404  *samples++ = v;
405  }
406  break;
409  for (; n > 0; n--) {
410  AV_WN16A(samples, s->table[*src++]);
411  samples += 2;
412  }
413  break;
414  case AV_CODEC_ID_PCM_DVD:
415  {
416  const uint8_t *src8;
417  dst_int32_t = (int32_t *)s->frame.data[0];
418  n /= avctx->channels;
419  switch (avctx->bits_per_coded_sample) {
420  case 20:
421  while (n--) {
422  c = avctx->channels;
423  src8 = src + 4 * c;
424  while (c--) {
425  *dst_int32_t++ = (bytestream_get_be16(&src) << 16) + ((*src8 & 0xf0) << 8);
426  *dst_int32_t++ = (bytestream_get_be16(&src) << 16) + ((*src8++ & 0x0f) << 12);
427  }
428  src = src8;
429  }
430  break;
431  case 24:
432  while (n--) {
433  c = avctx->channels;
434  src8 = src + 4 * c;
435  while (c--) {
436  *dst_int32_t++ = (bytestream_get_be16(&src) << 16) + ((*src8++) << 8);
437  *dst_int32_t++ = (bytestream_get_be16(&src) << 16) + ((*src8++) << 8);
438  }
439  src = src8;
440  }
441  break;
442  }
443  break;
444  }
445  case AV_CODEC_ID_PCM_LXF:
446  {
447  int i;
448  n /= avctx->channels;
449  for (c = 0; c < avctx->channels; c++) {
450  dst_int32_t = (int32_t *)s->frame.extended_data[c];
451  for (i = 0; i < n; i++) {
452  // extract low 20 bits and expand to 32 bits
453  *dst_int32_t++ = (src[2] << 28) |
454  (src[1] << 20) |
455  (src[0] << 12) |
456  ((src[2] & 0x0F) << 8) |
457  src[1];
458  // extract high 20 bits and expand to 32 bits
459  *dst_int32_t++ = (src[4] << 24) |
460  (src[3] << 16) |
461  ((src[2] & 0xF0) << 8) |
462  (src[4] << 4) |
463  (src[3] >> 4);
464  src += 5;
465  }
466  }
467  break;
468  }
469  default:
470  return -1;
471  }
472 
473  *got_frame_ptr = 1;
474  *(AVFrame *)data = s->frame;
475 
476  return buf_size;
477 }
478 
479 #define PCM_ENCODER_0(id_, sample_fmt_, name_, long_name_)
480 #define PCM_ENCODER_1(id_, sample_fmt_, name_, long_name_) \
481 AVCodec ff_ ## name_ ## _encoder = { \
482  .name = #name_, \
483  .type = AVMEDIA_TYPE_AUDIO, \
484  .id = AV_CODEC_ID_ ## id_, \
485  .init = pcm_encode_init, \
486  .encode2 = pcm_encode_frame, \
487  .close = pcm_encode_close, \
488  .capabilities = CODEC_CAP_VARIABLE_FRAME_SIZE, \
489  .sample_fmts = (const enum AVSampleFormat[]){ sample_fmt_, \
490  AV_SAMPLE_FMT_NONE }, \
491  .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
492 }
493 
494 #define PCM_ENCODER_2(cf, id, sample_fmt, name, long_name) \
495  PCM_ENCODER_ ## cf(id, sample_fmt, name, long_name)
496 #define PCM_ENCODER_3(cf, id, sample_fmt, name, long_name) \
497  PCM_ENCODER_2(cf, id, sample_fmt, name, long_name)
498 #define PCM_ENCODER(id, sample_fmt, name, long_name) \
499  PCM_ENCODER_3(CONFIG_ ## id ## _ENCODER, id, sample_fmt, name, long_name)
500 
501 #define PCM_DECODER_0(id, sample_fmt, name, long_name)
502 #define PCM_DECODER_1(id_, sample_fmt_, name_, long_name_) \
503 AVCodec ff_ ## name_ ## _decoder = { \
504  .name = #name_, \
505  .type = AVMEDIA_TYPE_AUDIO, \
506  .id = AV_CODEC_ID_ ## id_, \
507  .priv_data_size = sizeof(PCMDecode), \
508  .init = pcm_decode_init, \
509  .decode = pcm_decode_frame, \
510  .capabilities = CODEC_CAP_DR1, \
511  .sample_fmts = (const enum AVSampleFormat[]){ sample_fmt_, \
512  AV_SAMPLE_FMT_NONE }, \
513  .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
514 }
515 
516 #define PCM_DECODER_2(cf, id, sample_fmt, name, long_name) \
517  PCM_DECODER_ ## cf(id, sample_fmt, name, long_name)
518 #define PCM_DECODER_3(cf, id, sample_fmt, name, long_name) \
519  PCM_DECODER_2(cf, id, sample_fmt, name, long_name)
520 #define PCM_DECODER(id, sample_fmt, name, long_name) \
521  PCM_DECODER_3(CONFIG_ ## id ## _DECODER, id, sample_fmt, name, long_name)
522 
523 #define PCM_CODEC(id, sample_fmt_, name, long_name_) \
524  PCM_ENCODER(id, sample_fmt_, name, long_name_); \
525  PCM_DECODER(id, sample_fmt_, name, long_name_)
526 
527 /* Note: Do not forget to add new entries to the Makefile as well. */
528 PCM_CODEC (PCM_ALAW, AV_SAMPLE_FMT_S16, pcm_alaw, "PCM A-law");
529 PCM_DECODER(PCM_DVD, AV_SAMPLE_FMT_S32, pcm_dvd, "PCM signed 20|24-bit big-endian");
530 PCM_CODEC (PCM_F32BE, AV_SAMPLE_FMT_FLT, pcm_f32be, "PCM 32-bit floating point big-endian");
531 PCM_CODEC (PCM_F32LE, AV_SAMPLE_FMT_FLT, pcm_f32le, "PCM 32-bit floating point little-endian");
532 PCM_CODEC (PCM_F64BE, AV_SAMPLE_FMT_DBL, pcm_f64be, "PCM 64-bit floating point big-endian");
533 PCM_CODEC (PCM_F64LE, AV_SAMPLE_FMT_DBL, pcm_f64le, "PCM 64-bit floating point little-endian");
534 PCM_DECODER(PCM_LXF, AV_SAMPLE_FMT_S32P, pcm_lxf, "PCM signed 20-bit little-endian planar");
535 PCM_CODEC (PCM_MULAW, AV_SAMPLE_FMT_S16, pcm_mulaw, "PCM mu-law");
536 PCM_CODEC (PCM_S8, AV_SAMPLE_FMT_U8, pcm_s8, "PCM signed 8-bit");
537 PCM_CODEC (PCM_S16BE, AV_SAMPLE_FMT_S16, pcm_s16be, "PCM signed 16-bit big-endian");
538 PCM_CODEC (PCM_S16LE, AV_SAMPLE_FMT_S16, pcm_s16le, "PCM signed 16-bit little-endian");
539 PCM_DECODER(PCM_S16LE_PLANAR, AV_SAMPLE_FMT_S16P, pcm_s16le_planar, "PCM 16-bit little-endian planar");
540 PCM_CODEC (PCM_S24BE, AV_SAMPLE_FMT_S32, pcm_s24be, "PCM signed 24-bit big-endian");
541 PCM_CODEC (PCM_S24DAUD, AV_SAMPLE_FMT_S16, pcm_s24daud, "PCM D-Cinema audio signed 24-bit");
542 PCM_CODEC (PCM_S24LE, AV_SAMPLE_FMT_S32, pcm_s24le, "PCM signed 24-bit little-endian");
543 PCM_CODEC (PCM_S32BE, AV_SAMPLE_FMT_S32, pcm_s32be, "PCM signed 32-bit big-endian");
544 PCM_CODEC (PCM_S32LE, AV_SAMPLE_FMT_S32, pcm_s32le, "PCM signed 32-bit little-endian");
545 PCM_CODEC (PCM_U8, AV_SAMPLE_FMT_U8, pcm_u8, "PCM unsigned 8-bit");
546 PCM_CODEC (PCM_U16BE, AV_SAMPLE_FMT_S16, pcm_u16be, "PCM unsigned 16-bit big-endian");
547 PCM_CODEC (PCM_U16LE, AV_SAMPLE_FMT_S16, pcm_u16le, "PCM unsigned 16-bit little-endian");
548 PCM_CODEC (PCM_U24BE, AV_SAMPLE_FMT_S32, pcm_u24be, "PCM unsigned 24-bit big-endian");
549 PCM_CODEC (PCM_U24LE, AV_SAMPLE_FMT_S32, pcm_u24le, "PCM unsigned 24-bit little-endian");
550 PCM_CODEC (PCM_U32BE, AV_SAMPLE_FMT_S32, pcm_u32be, "PCM unsigned 32-bit big-endian");
551 PCM_CODEC (PCM_U32LE, AV_SAMPLE_FMT_S32, pcm_u32le, "PCM unsigned 32-bit little-endian");
552 PCM_DECODER(PCM_ZORK, AV_SAMPLE_FMT_U8, pcm_zork, "PCM Zork");