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 
52  return 0;
53 }
54 
65 #define ENCODE(type, endian, src, dst, n, shift, offset) \
66  samples_ ## type = (const type *) src; \
67  for (; n > 0; n--) { \
68  register type v = (*samples_ ## type++ >> shift) + offset; \
69  bytestream_put_ ## endian(&dst, v); \
70  }
71 
72 static int pcm_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
73  const AVFrame *frame, int *got_packet_ptr)
74 {
75  int n, sample_size, v, ret;
76  const short *samples;
77  unsigned char *dst;
78  const uint8_t *srcu8;
79  const int16_t *samples_int16_t;
80  const int32_t *samples_int32_t;
81  const int64_t *samples_int64_t;
82  const uint16_t *samples_uint16_t;
83  const uint32_t *samples_uint32_t;
84 
85  sample_size = av_get_bits_per_sample(avctx->codec->id) / 8;
86  n = frame->nb_samples * avctx->channels;
87  samples = (const short *)frame->data[0];
88 
89  if ((ret = ff_alloc_packet(avpkt, n * sample_size))) {
90  av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
91  return ret;
92  }
93  dst = avpkt->data;
94 
95  switch (avctx->codec->id) {
97  ENCODE(uint32_t, le32, samples, dst, n, 0, 0x80000000)
98  break;
100  ENCODE(uint32_t, be32, samples, dst, n, 0, 0x80000000)
101  break;
103  ENCODE(int32_t, le24, samples, dst, n, 8, 0)
104  break;
106  ENCODE(int32_t, be24, samples, dst, n, 8, 0)
107  break;
109  ENCODE(uint32_t, le24, samples, dst, n, 8, 0x800000)
110  break;
112  ENCODE(uint32_t, be24, samples, dst, n, 8, 0x800000)
113  break;
115  for (; n > 0; n--) {
116  uint32_t tmp = ff_reverse[(*samples >> 8) & 0xff] +
117  (ff_reverse[*samples & 0xff] << 8);
118  tmp <<= 4; // sync flags would go here
119  bytestream_put_be24(&dst, tmp);
120  samples++;
121  }
122  break;
124  ENCODE(uint16_t, le16, samples, dst, n, 0, 0x8000)
125  break;
127  ENCODE(uint16_t, be16, samples, dst, n, 0, 0x8000)
128  break;
129  case AV_CODEC_ID_PCM_S8:
130  srcu8 = frame->data[0];
131  for (; n > 0; n--) {
132  v = *srcu8++;
133  *dst++ = v - 128;
134  }
135  break;
136 #if HAVE_BIGENDIAN
138  ENCODE(int64_t, le64, samples, dst, n, 0, 0)
139  break;
142  ENCODE(int32_t, le32, samples, dst, n, 0, 0)
143  break;
145  ENCODE(int16_t, le16, samples, dst, n, 0, 0)
146  break;
151 #else
153  ENCODE(int64_t, be64, samples, dst, n, 0, 0)
154  break;
157  ENCODE(int32_t, be32, samples, dst, n, 0, 0)
158  break;
160  ENCODE(int16_t, be16, samples, dst, n, 0, 0)
161  break;
166 #endif /* HAVE_BIGENDIAN */
167  case AV_CODEC_ID_PCM_U8:
168  memcpy(dst, samples, n * sample_size);
169  dst += n * sample_size;
170  break;
172  for (; n > 0; n--) {
173  v = *samples++;
174  *dst++ = linear_to_alaw[(v + 32768) >> 2];
175  }
176  break;
178  for (; n > 0; n--) {
179  v = *samples++;
180  *dst++ = linear_to_ulaw[(v + 32768) >> 2];
181  }
182  break;
183  default:
184  return -1;
185  }
186 
187  *got_packet_ptr = 1;
188  return 0;
189 }
190 
191 typedef struct PCMDecode {
192  short table[256];
193 } PCMDecode;
194 
196 {
197  PCMDecode *s = avctx->priv_data;
198  int i;
199 
200  if (avctx->channels <= 0) {
201  av_log(avctx, AV_LOG_ERROR, "PCM channels out of bounds\n");
202  return AVERROR(EINVAL);
203  }
204 
205  switch (avctx->codec->id) {
207  for (i = 0; i < 256; i++)
208  s->table[i] = alaw2linear(i);
209  break;
211  for (i = 0; i < 256; i++)
212  s->table[i] = ulaw2linear(i);
213  break;
214  default:
215  break;
216  }
217 
218  avctx->sample_fmt = avctx->codec->sample_fmts[0];
219 
220  if (avctx->sample_fmt == AV_SAMPLE_FMT_S32)
222 
223  return 0;
224 }
225 
236 #define DECODE(size, endian, src, dst, n, shift, offset) \
237  for (; n > 0; n--) { \
238  uint ## size ## _t v = bytestream_get_ ## endian(&src); \
239  AV_WN ## size ## A(dst, (v - offset) << shift); \
240  dst += size / 8; \
241  }
242 
243 #if HAVE_BIGENDIAN
244 #define DECODE_PLANAR(size, endian, src, dst, n, shift, offset) \
245  { \
246  int n2; \
247  n /= avctx->channels; \
248  for (c = 0; c < avctx->channels; c++) { \
249  samples = frame->extended_data[c]; \
250  n2 = n; \
251  DECODE(size, endian, src, samples, n2, 0, 0) \
252  } \
253  }
254 #else
255 #define DECODE_PLANAR(size, endian, src, dst, n, shift, offset) \
256  { \
257  n /= avctx->channels; \
258  for (c = 0; c < avctx->channels; c++) { \
259  samples = frame->extended_data[c]; \
260  memcpy(samples, src, n * size / 8); \
261  src += n * size / 8; \
262  } \
263  }
264 #endif /* HAVE_BIGENDIAN */
265 
266 static int pcm_decode_frame(AVCodecContext *avctx, void *data,
267  int *got_frame_ptr, AVPacket *avpkt)
268 {
269  const uint8_t *src = avpkt->data;
270  int buf_size = avpkt->size;
271  PCMDecode *s = avctx->priv_data;
272  AVFrame *frame = data;
273  int sample_size, c, n, ret, samples_per_block;
274  uint8_t *samples;
275  int32_t *dst_int32_t;
276 
277  sample_size = av_get_bits_per_sample(avctx->codec_id) / 8;
278 
279  /* av_get_bits_per_sample returns 0 for AV_CODEC_ID_PCM_DVD */
280  samples_per_block = 1;
281  if (avctx->codec_id == AV_CODEC_ID_PCM_LXF) {
282  /* we process 40-bit blocks per channel for LXF */
283  samples_per_block = 2;
284  sample_size = 5;
285  }
286 
287  if (sample_size == 0) {
288  av_log(avctx, AV_LOG_ERROR, "Invalid sample_size\n");
289  return AVERROR(EINVAL);
290  }
291 
292  n = avctx->channels * sample_size;
293 
294  if (n && buf_size % n) {
295  if (buf_size < n) {
296  av_log(avctx, AV_LOG_ERROR, "invalid PCM packet\n");
297  return -1;
298  } else
299  buf_size -= buf_size % n;
300  }
301 
302  n = buf_size / sample_size;
303 
304  /* get output buffer */
305  frame->nb_samples = n * samples_per_block / avctx->channels;
306  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
307  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
308  return ret;
309  }
310  samples = frame->data[0];
311 
312  switch (avctx->codec->id) {
314  DECODE(32, le32, src, samples, n, 0, 0x80000000)
315  break;
317  DECODE(32, be32, src, samples, n, 0, 0x80000000)
318  break;
320  DECODE(32, le24, src, samples, n, 8, 0)
321  break;
323  DECODE(32, be24, src, samples, n, 8, 0)
324  break;
326  DECODE(32, le24, src, samples, n, 8, 0x800000)
327  break;
329  DECODE(32, be24, src, samples, n, 8, 0x800000)
330  break;
332  for (; n > 0; n--) {
333  uint32_t v = bytestream_get_be24(&src);
334  v >>= 4; // sync flags are here
335  AV_WN16A(samples, ff_reverse[(v >> 8) & 0xff] +
336  (ff_reverse[v & 0xff] << 8));
337  samples += 2;
338  }
339  break;
341  DECODE_PLANAR(16, be16, src, samples, n, 0, 0);
342  break;
344  DECODE_PLANAR(16, le16, src, samples, n, 0, 0);
345  break;
347  DECODE_PLANAR(32, le24, src, samples, n, 8, 0);
348  break;
350  DECODE_PLANAR(32, le32, src, samples, n, 0, 0);
351  break;
353  DECODE(16, le16, src, samples, n, 0, 0x8000)
354  break;
356  DECODE(16, be16, src, samples, n, 0, 0x8000)
357  break;
358  case AV_CODEC_ID_PCM_S8:
359  for (; n > 0; n--)
360  *samples++ = *src++ + 128;
361  break;
362 #if HAVE_BIGENDIAN
364  DECODE(64, le64, src, samples, n, 0, 0)
365  break;
368  DECODE(32, le32, src, samples, n, 0, 0)
369  break;
371  DECODE(16, le16, src, samples, n, 0, 0)
372  break;
377 #else
379  DECODE(64, be64, src, samples, n, 0, 0)
380  break;
383  DECODE(32, be32, src, samples, n, 0, 0)
384  break;
386  DECODE(16, be16, src, samples, n, 0, 0)
387  break;
392 #endif /* HAVE_BIGENDIAN */
393  case AV_CODEC_ID_PCM_U8:
394  memcpy(samples, src, n * sample_size);
395  break;
397  for (; n > 0; n--) {
398  int v = *src++;
399  if (v < 128)
400  v = 128 - v;
401  *samples++ = v;
402  }
403  break;
406  for (; n > 0; n--) {
407  AV_WN16A(samples, s->table[*src++]);
408  samples += 2;
409  }
410  break;
411  case AV_CODEC_ID_PCM_LXF:
412  {
413  int i;
414  n /= avctx->channels;
415  for (c = 0; c < avctx->channels; c++) {
416  dst_int32_t = (int32_t *)frame->extended_data[c];
417  for (i = 0; i < n; i++) {
418  // extract low 20 bits and expand to 32 bits
419  *dst_int32_t++ = (src[2] << 28) |
420  (src[1] << 20) |
421  (src[0] << 12) |
422  ((src[2] & 0x0F) << 8) |
423  src[1];
424  // extract high 20 bits and expand to 32 bits
425  *dst_int32_t++ = (src[4] << 24) |
426  (src[3] << 16) |
427  ((src[2] & 0xF0) << 8) |
428  (src[4] << 4) |
429  (src[3] >> 4);
430  src += 5;
431  }
432  }
433  break;
434  }
435  default:
436  return -1;
437  }
438 
439  *got_frame_ptr = 1;
440 
441  return buf_size;
442 }
443 
444 #define PCM_ENCODER_0(id_, sample_fmt_, name_, long_name_)
445 #define PCM_ENCODER_1(id_, sample_fmt_, name_, long_name_) \
446 AVCodec ff_ ## name_ ## _encoder = { \
447  .name = #name_, \
448  .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
449  .type = AVMEDIA_TYPE_AUDIO, \
450  .id = AV_CODEC_ID_ ## id_, \
451  .init = pcm_encode_init, \
452  .encode2 = pcm_encode_frame, \
453  .capabilities = AV_CODEC_CAP_VARIABLE_FRAME_SIZE, \
454  .sample_fmts = (const enum AVSampleFormat[]){ sample_fmt_, \
455  AV_SAMPLE_FMT_NONE }, \
456 }
457 
458 #define PCM_ENCODER_2(cf, id, sample_fmt, name, long_name) \
459  PCM_ENCODER_ ## cf(id, sample_fmt, name, long_name)
460 #define PCM_ENCODER_3(cf, id, sample_fmt, name, long_name) \
461  PCM_ENCODER_2(cf, id, sample_fmt, name, long_name)
462 #define PCM_ENCODER(id, sample_fmt, name, long_name) \
463  PCM_ENCODER_3(CONFIG_ ## id ## _ENCODER, id, sample_fmt, name, long_name)
464 
465 #define PCM_DECODER_0(id, sample_fmt, name, long_name)
466 #define PCM_DECODER_1(id_, sample_fmt_, name_, long_name_) \
467 AVCodec ff_ ## name_ ## _decoder = { \
468  .name = #name_, \
469  .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
470  .type = AVMEDIA_TYPE_AUDIO, \
471  .id = AV_CODEC_ID_ ## id_, \
472  .priv_data_size = sizeof(PCMDecode), \
473  .init = pcm_decode_init, \
474  .decode = pcm_decode_frame, \
475  .capabilities = AV_CODEC_CAP_DR1, \
476  .sample_fmts = (const enum AVSampleFormat[]){ sample_fmt_, \
477  AV_SAMPLE_FMT_NONE }, \
478 }
479 
480 #define PCM_DECODER_2(cf, id, sample_fmt, name, long_name) \
481  PCM_DECODER_ ## cf(id, sample_fmt, name, long_name)
482 #define PCM_DECODER_3(cf, id, sample_fmt, name, long_name) \
483  PCM_DECODER_2(cf, id, sample_fmt, name, long_name)
484 #define PCM_DECODER(id, sample_fmt, name, long_name) \
485  PCM_DECODER_3(CONFIG_ ## id ## _DECODER, id, sample_fmt, name, long_name)
486 
487 #define PCM_CODEC(id, sample_fmt_, name, long_name_) \
488  PCM_ENCODER(id, sample_fmt_, name, long_name_); \
489  PCM_DECODER(id, sample_fmt_, name, long_name_)
490 
491 /* Note: Do not forget to add new entries to the Makefile as well. */
492 PCM_CODEC (PCM_ALAW, AV_SAMPLE_FMT_S16, pcm_alaw, "PCM A-law");
493 PCM_CODEC (PCM_F32BE, AV_SAMPLE_FMT_FLT, pcm_f32be, "PCM 32-bit floating point big-endian");
494 PCM_CODEC (PCM_F32LE, AV_SAMPLE_FMT_FLT, pcm_f32le, "PCM 32-bit floating point little-endian");
495 PCM_CODEC (PCM_F64BE, AV_SAMPLE_FMT_DBL, pcm_f64be, "PCM 64-bit floating point big-endian");
496 PCM_CODEC (PCM_F64LE, AV_SAMPLE_FMT_DBL, pcm_f64le, "PCM 64-bit floating point little-endian");
497 PCM_DECODER(PCM_LXF, AV_SAMPLE_FMT_S32P, pcm_lxf, "PCM signed 20-bit little-endian planar");
498 PCM_CODEC (PCM_MULAW, AV_SAMPLE_FMT_S16, pcm_mulaw, "PCM mu-law");
499 PCM_CODEC (PCM_S8, AV_SAMPLE_FMT_U8, pcm_s8, "PCM signed 8-bit");
500 PCM_CODEC (PCM_S16BE, AV_SAMPLE_FMT_S16, pcm_s16be, "PCM signed 16-bit big-endian");
501 PCM_DECODER(PCM_S16BE_PLANAR, AV_SAMPLE_FMT_S16P,pcm_s16be_planar, "PCM signed 16-bit big-endian planar");
502 PCM_CODEC (PCM_S16LE, AV_SAMPLE_FMT_S16, pcm_s16le, "PCM signed 16-bit little-endian");
503 PCM_DECODER(PCM_S16LE_PLANAR, AV_SAMPLE_FMT_S16P, pcm_s16le_planar, "PCM 16-bit little-endian planar");
504 PCM_CODEC (PCM_S24BE, AV_SAMPLE_FMT_S32, pcm_s24be, "PCM signed 24-bit big-endian");
505 PCM_CODEC (PCM_S24DAUD, AV_SAMPLE_FMT_S16, pcm_s24daud, "PCM D-Cinema audio signed 24-bit");
506 PCM_CODEC (PCM_S24LE, AV_SAMPLE_FMT_S32, pcm_s24le, "PCM signed 24-bit little-endian");
507 PCM_DECODER(PCM_S24LE_PLANAR, AV_SAMPLE_FMT_S32P,pcm_s24le_planar, "PCM signed 24-bit little-endian planar");
508 PCM_CODEC (PCM_S32BE, AV_SAMPLE_FMT_S32, pcm_s32be, "PCM signed 32-bit big-endian");
509 PCM_CODEC (PCM_S32LE, AV_SAMPLE_FMT_S32, pcm_s32le, "PCM signed 32-bit little-endian");
510 PCM_DECODER(PCM_S32LE_PLANAR, AV_SAMPLE_FMT_S32P,pcm_s32le_planar, "PCM signed 32-bit little-endian planar");
511 PCM_CODEC (PCM_U8, AV_SAMPLE_FMT_U8, pcm_u8, "PCM unsigned 8-bit");
512 PCM_CODEC (PCM_U16BE, AV_SAMPLE_FMT_S16, pcm_u16be, "PCM unsigned 16-bit big-endian");
513 PCM_CODEC (PCM_U16LE, AV_SAMPLE_FMT_S16, pcm_u16le, "PCM unsigned 16-bit little-endian");
514 PCM_CODEC (PCM_U24BE, AV_SAMPLE_FMT_S32, pcm_u24be, "PCM unsigned 24-bit big-endian");
515 PCM_CODEC (PCM_U24LE, AV_SAMPLE_FMT_S32, pcm_u24le, "PCM unsigned 24-bit little-endian");
516 PCM_CODEC (PCM_U32BE, AV_SAMPLE_FMT_S32, pcm_u32be, "PCM unsigned 32-bit big-endian");
517 PCM_CODEC (PCM_U32LE, AV_SAMPLE_FMT_S32, pcm_u32le, "PCM unsigned 32-bit little-endian");
518 PCM_DECODER(PCM_ZORK, AV_SAMPLE_FMT_U8, pcm_zork, "PCM Zork");
const struct AVCodec * codec
Definition: avcodec.h:1418
This structure describes decoded (raw) audio or video data.
Definition: frame.h:140
static void pcm_alaw_tableinit(void)
Definition: pcm_tablegen.h:105
static void pcm_ulaw_tableinit(void)
Definition: pcm_tablegen.h:110
#define DECODE_PLANAR(size, endian, src, dst, n, shift, offset)
Definition: pcm.c:255
static av_cold int ulaw2linear(unsigned char u_val)
Definition: pcm_tablegen.h:55
static int pcm_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
Definition: pcm.c:72
int size
Definition: avcodec.h:1347
av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (%s)\, len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt), use_generic ? ac->func_descr_generic :ac->func_descr)
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:2776
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:2189
Macro definitions for various function/variable attributes.
Definition: pcm.c:191
short table[256]
Definition: pcm.c:192
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:2160
uint8_t
#define av_cold
Definition: attributes.h:66
AV_SAMPLE_FMT_U8
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:1346
static uint8_t linear_to_ulaw[16384]
Definition: pcm_tablegen.h:79
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2769
signed 32 bits
Definition: samplefmt.h:64
#define src
Definition: vp8dsp.c:254
static int pcm_decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
Definition: pcm.c:266
enum AVCodecID id
Definition: avcodec.h:3134
#define PCM_CODEC(id, sample_fmt_, name, long_name_)
Definition: pcm.c:487
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:124
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:2348
#define AVERROR(e)
Definition: error.h:43
#define DECODE(size, endian, src, dst, n, shift, offset)
Read PCM samples macro.
Definition: pcm.c:236
#define ENCODE(type, endian, src, dst, n, shift, offset)
Write PCM samples macro.
Definition: pcm.c:65
static av_cold int pcm_encode_init(AVCodecContext *avctx)
Definition: pcm.c:34
int bit_rate
the average bitrate
Definition: avcodec.h:1473
static av_cold int alaw2linear(unsigned char a_val)
Definition: pcm_tablegen.h:40
signed 32 bits, planar
Definition: samplefmt.h:70
int32_t
int ff_alloc_packet(AVPacket *avpkt, int size)
Check AVPacket size and/or allocate data.
Definition: utils.c:1211
#define AV_WN16A(p, v)
Definition: intreadwrite.h:465
if(ac->has_optimized_func)
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:2172
Libavcodec external API header.
enum AVCodecID codec_id
Definition: avcodec.h:1426
int sample_rate
samples per second
Definition: avcodec.h:2152
main external API structure.
Definition: avcodec.h:1409
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:589
static av_cold int pcm_decode_init(AVCodecContext *avctx)
Definition: pcm.c:195
#define PCM_DECODER(id, sample_fmt, name, long_name)
Definition: pcm.c:484
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:146
common internal api header.
signed 16 bits
Definition: samplefmt.h:63
static uint8_t linear_to_alaw[16384]
Definition: pcm_tablegen.h:78
void * priv_data
Definition: avcodec.h:1451
int channels
number of audio channels
Definition: avcodec.h:2153
static uint8_t tmp[8]
Definition: des.c:38
signed 16 bits, planar
Definition: samplefmt.h:69
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:3143
uint8_t ** extended_data
pointers to the data planes/channels.
Definition: frame.h:174
This structure stores compressed data.
Definition: avcodec.h:1323
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:184
for(j=16;j >0;--j)