Libav
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;
51  avctx->coded_frame = av_frame_alloc();
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 {
202  short table[256];
203 } PCMDecode;
204 
206 {
207  PCMDecode *s = avctx->priv_data;
208  int i;
209 
210  if (avctx->channels <= 0) {
211  av_log(avctx, AV_LOG_ERROR, "PCM channels out of bounds\n");
212  return AVERROR(EINVAL);
213  }
214 
215  switch (avctx->codec->id) {
217  for (i = 0; i < 256; i++)
218  s->table[i] = alaw2linear(i);
219  break;
221  for (i = 0; i < 256; i++)
222  s->table[i] = ulaw2linear(i);
223  break;
224  default:
225  break;
226  }
227 
228  avctx->sample_fmt = avctx->codec->sample_fmts[0];
229 
230  if (avctx->sample_fmt == AV_SAMPLE_FMT_S32)
232 
233  return 0;
234 }
235 
246 #define DECODE(size, endian, src, dst, n, shift, offset) \
247  for (; n > 0; n--) { \
248  uint ## size ## _t v = bytestream_get_ ## endian(&src); \
249  AV_WN ## size ## A(dst, (v - offset) << shift); \
250  dst += size / 8; \
251  }
252 
253 #if HAVE_BIGENDIAN
254 #define DECODE_PLANAR(size, endian, src, dst, n, shift, offset) \
255  { \
256  int n2; \
257  n /= avctx->channels; \
258  for (c = 0; c < avctx->channels; c++) { \
259  samples = frame->extended_data[c]; \
260  n2 = n; \
261  DECODE(size, endian, src, samples, n2, 0, 0) \
262  } \
263  }
264 #else
265 #define DECODE_PLANAR(size, endian, src, dst, n, shift, offset) \
266  { \
267  n /= avctx->channels; \
268  for (c = 0; c < avctx->channels; c++) { \
269  samples = frame->extended_data[c]; \
270  memcpy(samples, src, n * size / 8); \
271  src += n * size / 8; \
272  } \
273  }
274 #endif /* HAVE_BIGENDIAN */
275 
276 static int pcm_decode_frame(AVCodecContext *avctx, void *data,
277  int *got_frame_ptr, AVPacket *avpkt)
278 {
279  const uint8_t *src = avpkt->data;
280  int buf_size = avpkt->size;
281  PCMDecode *s = avctx->priv_data;
282  AVFrame *frame = data;
283  int sample_size, c, n, ret, samples_per_block;
284  uint8_t *samples;
285  int32_t *dst_int32_t;
286 
287  sample_size = av_get_bits_per_sample(avctx->codec_id) / 8;
288 
289  /* av_get_bits_per_sample returns 0 for AV_CODEC_ID_PCM_DVD */
290  samples_per_block = 1;
291  if (avctx->codec_id == AV_CODEC_ID_PCM_LXF) {
292  /* we process 40-bit blocks per channel for LXF */
293  samples_per_block = 2;
294  sample_size = 5;
295  }
296 
297  if (sample_size == 0) {
298  av_log(avctx, AV_LOG_ERROR, "Invalid sample_size\n");
299  return AVERROR(EINVAL);
300  }
301 
302  n = avctx->channels * sample_size;
303 
304  if (n && buf_size % n) {
305  if (buf_size < n) {
306  av_log(avctx, AV_LOG_ERROR, "invalid PCM packet\n");
307  return -1;
308  } else
309  buf_size -= buf_size % n;
310  }
311 
312  n = buf_size / sample_size;
313 
314  /* get output buffer */
315  frame->nb_samples = n * samples_per_block / avctx->channels;
316  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
317  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
318  return ret;
319  }
320  samples = frame->data[0];
321 
322  switch (avctx->codec->id) {
324  DECODE(32, le32, src, samples, n, 0, 0x80000000)
325  break;
327  DECODE(32, be32, src, samples, n, 0, 0x80000000)
328  break;
330  DECODE(32, le24, src, samples, n, 8, 0)
331  break;
333  DECODE(32, be24, src, samples, n, 8, 0)
334  break;
336  DECODE(32, le24, src, samples, n, 8, 0x800000)
337  break;
339  DECODE(32, be24, src, samples, n, 8, 0x800000)
340  break;
342  for (; n > 0; n--) {
343  uint32_t v = bytestream_get_be24(&src);
344  v >>= 4; // sync flags are here
345  AV_WN16A(samples, ff_reverse[(v >> 8) & 0xff] +
346  (ff_reverse[v & 0xff] << 8));
347  samples += 2;
348  }
349  break;
351  DECODE_PLANAR(16, le16, src, samples, n, 0, 0);
352  break;
354  DECODE_PLANAR(32, le24, src, samples, n, 8, 0);
355  break;
357  DECODE_PLANAR(32, le32, src, samples, n, 0, 0);
358  break;
360  DECODE(16, le16, src, samples, n, 0, 0x8000)
361  break;
363  DECODE(16, be16, src, samples, n, 0, 0x8000)
364  break;
365  case AV_CODEC_ID_PCM_S8:
366  for (; n > 0; n--)
367  *samples++ = *src++ + 128;
368  break;
369 #if HAVE_BIGENDIAN
371  DECODE(64, le64, src, samples, n, 0, 0)
372  break;
375  DECODE(32, le32, src, samples, n, 0, 0)
376  break;
378  DECODE(16, le16, src, samples, n, 0, 0)
379  break;
384 #else
386  DECODE(64, be64, src, samples, n, 0, 0)
387  break;
390  DECODE(32, be32, src, samples, n, 0, 0)
391  break;
393  DECODE(16, be16, src, samples, n, 0, 0)
394  break;
399 #endif /* HAVE_BIGENDIAN */
400  case AV_CODEC_ID_PCM_U8:
401  memcpy(samples, src, n * sample_size);
402  break;
404  for (; n > 0; n--) {
405  int v = *src++;
406  if (v < 128)
407  v = 128 - v;
408  *samples++ = v;
409  }
410  break;
413  for (; n > 0; n--) {
414  AV_WN16A(samples, s->table[*src++]);
415  samples += 2;
416  }
417  break;
418  case AV_CODEC_ID_PCM_LXF:
419  {
420  int i;
421  n /= avctx->channels;
422  for (c = 0; c < avctx->channels; c++) {
423  dst_int32_t = (int32_t *)frame->extended_data[c];
424  for (i = 0; i < n; i++) {
425  // extract low 20 bits and expand to 32 bits
426  *dst_int32_t++ = (src[2] << 28) |
427  (src[1] << 20) |
428  (src[0] << 12) |
429  ((src[2] & 0x0F) << 8) |
430  src[1];
431  // extract high 20 bits and expand to 32 bits
432  *dst_int32_t++ = (src[4] << 24) |
433  (src[3] << 16) |
434  ((src[2] & 0xF0) << 8) |
435  (src[4] << 4) |
436  (src[3] >> 4);
437  src += 5;
438  }
439  }
440  break;
441  }
442  default:
443  return -1;
444  }
445 
446  *got_frame_ptr = 1;
447 
448  return buf_size;
449 }
450 
451 #define PCM_ENCODER_0(id_, sample_fmt_, name_, long_name_)
452 #define PCM_ENCODER_1(id_, sample_fmt_, name_, long_name_) \
453 AVCodec ff_ ## name_ ## _encoder = { \
454  .name = #name_, \
455  .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
456  .type = AVMEDIA_TYPE_AUDIO, \
457  .id = AV_CODEC_ID_ ## id_, \
458  .init = pcm_encode_init, \
459  .encode2 = pcm_encode_frame, \
460  .close = pcm_encode_close, \
461  .capabilities = CODEC_CAP_VARIABLE_FRAME_SIZE, \
462  .sample_fmts = (const enum AVSampleFormat[]){ sample_fmt_, \
463  AV_SAMPLE_FMT_NONE }, \
464 }
465 
466 #define PCM_ENCODER_2(cf, id, sample_fmt, name, long_name) \
467  PCM_ENCODER_ ## cf(id, sample_fmt, name, long_name)
468 #define PCM_ENCODER_3(cf, id, sample_fmt, name, long_name) \
469  PCM_ENCODER_2(cf, id, sample_fmt, name, long_name)
470 #define PCM_ENCODER(id, sample_fmt, name, long_name) \
471  PCM_ENCODER_3(CONFIG_ ## id ## _ENCODER, id, sample_fmt, name, long_name)
472 
473 #define PCM_DECODER_0(id, sample_fmt, name, long_name)
474 #define PCM_DECODER_1(id_, sample_fmt_, name_, long_name_) \
475 AVCodec ff_ ## name_ ## _decoder = { \
476  .name = #name_, \
477  .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
478  .type = AVMEDIA_TYPE_AUDIO, \
479  .id = AV_CODEC_ID_ ## id_, \
480  .priv_data_size = sizeof(PCMDecode), \
481  .init = pcm_decode_init, \
482  .decode = pcm_decode_frame, \
483  .capabilities = CODEC_CAP_DR1, \
484  .sample_fmts = (const enum AVSampleFormat[]){ sample_fmt_, \
485  AV_SAMPLE_FMT_NONE }, \
486 }
487 
488 #define PCM_DECODER_2(cf, id, sample_fmt, name, long_name) \
489  PCM_DECODER_ ## cf(id, sample_fmt, name, long_name)
490 #define PCM_DECODER_3(cf, id, sample_fmt, name, long_name) \
491  PCM_DECODER_2(cf, id, sample_fmt, name, long_name)
492 #define PCM_DECODER(id, sample_fmt, name, long_name) \
493  PCM_DECODER_3(CONFIG_ ## id ## _DECODER, id, sample_fmt, name, long_name)
494 
495 #define PCM_CODEC(id, sample_fmt_, name, long_name_) \
496  PCM_ENCODER(id, sample_fmt_, name, long_name_); \
497  PCM_DECODER(id, sample_fmt_, name, long_name_)
498 
499 /* Note: Do not forget to add new entries to the Makefile as well. */
500 PCM_CODEC (PCM_ALAW, AV_SAMPLE_FMT_S16, pcm_alaw, "PCM A-law");
501 PCM_CODEC (PCM_F32BE, AV_SAMPLE_FMT_FLT, pcm_f32be, "PCM 32-bit floating point big-endian");
502 PCM_CODEC (PCM_F32LE, AV_SAMPLE_FMT_FLT, pcm_f32le, "PCM 32-bit floating point little-endian");
503 PCM_CODEC (PCM_F64BE, AV_SAMPLE_FMT_DBL, pcm_f64be, "PCM 64-bit floating point big-endian");
504 PCM_CODEC (PCM_F64LE, AV_SAMPLE_FMT_DBL, pcm_f64le, "PCM 64-bit floating point little-endian");
505 PCM_DECODER(PCM_LXF, AV_SAMPLE_FMT_S32P, pcm_lxf, "PCM signed 20-bit little-endian planar");
506 PCM_CODEC (PCM_MULAW, AV_SAMPLE_FMT_S16, pcm_mulaw, "PCM mu-law");
507 PCM_CODEC (PCM_S8, AV_SAMPLE_FMT_U8, pcm_s8, "PCM signed 8-bit");
508 PCM_CODEC (PCM_S16BE, AV_SAMPLE_FMT_S16, pcm_s16be, "PCM signed 16-bit big-endian");
509 PCM_CODEC (PCM_S16LE, AV_SAMPLE_FMT_S16, pcm_s16le, "PCM signed 16-bit little-endian");
510 PCM_DECODER(PCM_S16LE_PLANAR, AV_SAMPLE_FMT_S16P, pcm_s16le_planar, "PCM 16-bit little-endian planar");
511 PCM_CODEC (PCM_S24BE, AV_SAMPLE_FMT_S32, pcm_s24be, "PCM signed 24-bit big-endian");
512 PCM_CODEC (PCM_S24DAUD, AV_SAMPLE_FMT_S16, pcm_s24daud, "PCM D-Cinema audio signed 24-bit");
513 PCM_CODEC (PCM_S24LE, AV_SAMPLE_FMT_S32, pcm_s24le, "PCM signed 24-bit little-endian");
514 PCM_DECODER(PCM_S24LE_PLANAR, AV_SAMPLE_FMT_S32P,pcm_s24le_planar, "PCM signed 24-bit little-endian planar");
515 PCM_CODEC (PCM_S32BE, AV_SAMPLE_FMT_S32, pcm_s32be, "PCM signed 32-bit big-endian");
516 PCM_CODEC (PCM_S32LE, AV_SAMPLE_FMT_S32, pcm_s32le, "PCM signed 32-bit little-endian");
517 PCM_DECODER(PCM_S32LE_PLANAR, AV_SAMPLE_FMT_S32P,pcm_s32le_planar, "PCM signed 32-bit little-endian planar");
518 PCM_CODEC (PCM_U8, AV_SAMPLE_FMT_U8, pcm_u8, "PCM unsigned 8-bit");
519 PCM_CODEC (PCM_U16BE, AV_SAMPLE_FMT_S16, pcm_u16be, "PCM unsigned 16-bit big-endian");
520 PCM_CODEC (PCM_U16LE, AV_SAMPLE_FMT_S16, pcm_u16le, "PCM unsigned 16-bit little-endian");
521 PCM_CODEC (PCM_U24BE, AV_SAMPLE_FMT_S32, pcm_u24be, "PCM unsigned 24-bit big-endian");
522 PCM_CODEC (PCM_U24LE, AV_SAMPLE_FMT_S32, pcm_u24le, "PCM unsigned 24-bit little-endian");
523 PCM_CODEC (PCM_U32BE, AV_SAMPLE_FMT_S32, pcm_u32be, "PCM unsigned 32-bit big-endian");
524 PCM_CODEC (PCM_U32LE, AV_SAMPLE_FMT_S32, pcm_u32le, "PCM unsigned 32-bit little-endian");
525 PCM_DECODER(PCM_ZORK, AV_SAMPLE_FMT_U8, pcm_zork, "PCM Zork");
const struct AVCodec * codec
Definition: avcodec.h:1059
This structure describes decoded (raw) audio or video data.
Definition: frame.h:135
static void pcm_alaw_tableinit(void)
Definition: pcm_tablegen.h:108
AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:2532
static void pcm_ulaw_tableinit(void)
Definition: pcm_tablegen.h:113
#define DECODE_PLANAR(size, endian, src, dst, n, shift, offset)
Definition: pcm.c:265
static av_cold int ulaw2linear(unsigned char u_val)
Definition: pcm_tablegen.h:58
static int pcm_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
Definition: pcm.c:82
int size
Definition: avcodec.h:974
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:2514
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:1828
Macro definitions for various function/variable attributes.
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:198
Definition: pcm.c:201
short table[256]
Definition: pcm.c:202
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1799
uint8_t
#define av_cold
Definition: attributes.h:66
AV_SAMPLE_FMT_U8
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:57
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:973
static uint8_t linear_to_ulaw[16384]
Definition: pcm_tablegen.h:82
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2507
signed 32 bits
Definition: samplefmt.h:65
static int pcm_decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
Definition: pcm.c:276
enum AVCodecID id
Definition: avcodec.h:2810
#define PCM_CODEC(id, sample_fmt_, name, long_name_)
Definition: pcm.c:495
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:2043
#define AVERROR(e)
Definition: error.h:43
#define DECODE(size, endian, src, dst, n, shift, offset)
Read PCM samples macro.
Definition: pcm.c:246
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:169
static av_cold int pcm_encode_close(AVCodecContext *avctx)
Definition: pcm.c:58
#define ENCODE(type, endian, src, dst, n, shift, offset)
Write PCM samples macro.
Definition: pcm.c:75
static av_cold int pcm_encode_init(AVCodecContext *avctx)
Definition: pcm.c:34
int bit_rate
the average bitrate
Definition: avcodec.h:1114
static av_cold int alaw2linear(unsigned char a_val)
Definition: pcm_tablegen.h:43
signed 32 bits, planar
Definition: samplefmt.h:71
int32_t
int ff_alloc_packet(AVPacket *avpkt, int size)
Check AVPacket size and/or allocate data.
Definition: utils.c:1245
#define AV_WN16A(p, v)
Definition: intreadwrite.h:454
if(ac->has_optimized_func)
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1811
Libavcodec external API header.
enum AVCodecID codec_id
Definition: avcodec.h:1067
int sample_rate
samples per second
Definition: avcodec.h:1791
main external API structure.
Definition: avcodec.h:1050
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:612
static av_cold int pcm_decode_init(AVCodecContext *avctx)
Definition: pcm.c:205
#define PCM_DECODER(id, sample_fmt, name, long_name)
Definition: pcm.c:492
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:141
common internal api header.
signed 16 bits
Definition: samplefmt.h:64
static uint8_t linear_to_alaw[16384]
Definition: pcm_tablegen.h:81
void * priv_data
Definition: avcodec.h:1092
int channels
number of audio channels
Definition: avcodec.h:1792
signed 16 bits, planar
Definition: samplefmt.h:70
const uint8_t ff_reverse[256]
Definition: mathtables.c:72
enum AVSampleFormat * sample_fmts
array of supported sample formats, or NULL if unknown, array is terminated by -1
Definition: avcodec.h:2819
uint8_t ** extended_data
pointers to the data planes/channels.
Definition: frame.h:169
This structure stores compressed data.
Definition: avcodec.h:950
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:179
for(j=16;j >0;--j)