Libav
pcm-bluray.c
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1 /*
2  * LPCM codecs for PCM format found in Blu-ray PCM streams
3  * Copyright (c) 2009, 2013 Christian Schmidt
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 
28 #include "avcodec.h"
29 #include "bytestream.h"
30 #include "internal.h"
31 
32 /*
33  * Channel Mapping according to
34  * Blu-ray Disc Read-Only Format Version 1
35  * Part 3: Audio Visual Basic Specifications
36  * mono M1 X
37  * stereo L R
38  * 3/0 L R C X
39  * 2/1 L R S X
40  * 3/1 L R C S
41  * 2/2 L R LS RS
42  * 3/2 L R C LS RS X
43  * 3/2+lfe L R C LS RS lfe
44  * 3/4 L R C LS Rls Rrs RS X
45  * 3/4+lfe L R C LS Rls Rrs RS lfe
46  */
47 
54  const uint8_t *header)
55 {
56  static const uint8_t bits_per_samples[4] = { 0, 16, 20, 24 };
57  static const uint32_t channel_layouts[16] = {
61  AV_CH_LAYOUT_7POINT1, 0, 0, 0, 0
62  };
63  static const uint8_t channels[16] = {
64  0, 1, 0, 2, 3, 3, 4, 4, 5, 6, 7, 8, 0, 0, 0, 0
65  };
66  uint8_t channel_layout = header[2] >> 4;
67 
68  if (avctx->debug & FF_DEBUG_PICT_INFO)
69  av_dlog(avctx, "pcm_bluray_parse_header: header = %02x%02x%02x%02x\n",
70  header[0], header[1], header[2], header[3]);
71 
72  /* get the sample depth and derive the sample format from it */
73  avctx->bits_per_coded_sample = bits_per_samples[header[3] >> 6];
74  if (!avctx->bits_per_coded_sample) {
75  av_log(avctx, AV_LOG_ERROR, "reserved sample depth (0)\n");
76  return AVERROR_INVALIDDATA;
77  }
78  avctx->sample_fmt = avctx->bits_per_coded_sample == 16 ? AV_SAMPLE_FMT_S16
81 
82  /* get the sample rate. Not all values are used. */
83  switch (header[2] & 0x0f) {
84  case 1:
85  avctx->sample_rate = 48000;
86  break;
87  case 4:
88  avctx->sample_rate = 96000;
89  break;
90  case 5:
91  avctx->sample_rate = 192000;
92  break;
93  default:
94  avctx->sample_rate = 0;
95  av_log(avctx, AV_LOG_ERROR, "reserved sample rate (%d)\n",
96  header[2] & 0x0f);
97  return AVERROR_INVALIDDATA;
98  }
99 
100  /*
101  * get the channel number (and mapping). Not all values are used.
102  * It must be noted that the number of channels in the MPEG stream can
103  * differ from the actual meaningful number, e.g. mono audio still has two
104  * channels, one being empty.
105  */
106  avctx->channel_layout = channel_layouts[channel_layout];
107  avctx->channels = channels[channel_layout];
108  if (!avctx->channels) {
109  av_log(avctx, AV_LOG_ERROR, "reserved channel configuration (%d)\n",
110  channel_layout);
111  return AVERROR_INVALIDDATA;
112  }
113 
114  avctx->bit_rate = FFALIGN(avctx->channels, 2) * avctx->sample_rate *
115  avctx->bits_per_coded_sample;
116 
117  if (avctx->debug & FF_DEBUG_PICT_INFO)
118  av_dlog(avctx,
119  "pcm_bluray_parse_header: %d channels, %d bits per sample, %d Hz, %d bit/s\n",
120  avctx->channels, avctx->bits_per_coded_sample,
121  avctx->sample_rate, avctx->bit_rate);
122  return 0;
123 }
124 
125 static int pcm_bluray_decode_frame(AVCodecContext *avctx, void *data,
126  int *got_frame_ptr, AVPacket *avpkt)
127 {
128  AVFrame *frame = data;
129  const uint8_t *src = avpkt->data;
130  int buf_size = avpkt->size;
131  GetByteContext gb;
132  int num_source_channels, channel, retval;
133  int sample_size, samples;
134  int16_t *dst16;
135  int32_t *dst32;
136 
137  if (buf_size < 4) {
138  av_log(avctx, AV_LOG_ERROR, "PCM packet too small\n");
139  return AVERROR_INVALIDDATA;
140  }
141 
142  if ((retval = pcm_bluray_parse_header(avctx, src)))
143  return retval;
144  src += 4;
145  buf_size -= 4;
146 
147  bytestream2_init(&gb, src, buf_size);
148 
149  /* There's always an even number of channels in the source */
150  num_source_channels = FFALIGN(avctx->channels, 2);
151  sample_size = (num_source_channels *
152  (avctx->sample_fmt == AV_SAMPLE_FMT_S16 ? 16 : 24)) >> 3;
153  samples = buf_size / sample_size;
154 
155  /* get output buffer */
156  frame->nb_samples = samples;
157  if ((retval = ff_get_buffer(avctx, frame, 0)) < 0) {
158  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
159  return retval;
160  }
161  dst16 = (int16_t *)frame->data[0];
162  dst32 = (int32_t *)frame->data[0];
163 
164  if (samples) {
165  switch (avctx->channel_layout) {
166  /* cases with same number of source and coded channels */
167  case AV_CH_LAYOUT_STEREO:
169  case AV_CH_LAYOUT_2_2:
170  samples *= num_source_channels;
171  if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
172 #if HAVE_BIGENDIAN
173  bytestream2_get_buffer(&gb, dst16, buf_size);
174 #else
175  do {
176  *dst16++ = bytestream2_get_be16u(&gb);
177  } while (--samples);
178 #endif
179  } else {
180  do {
181  *dst32++ = bytestream2_get_be24u(&gb) << 8;
182  } while (--samples);
183  }
184  break;
185  /* cases where number of source channels = coded channels + 1 */
186  case AV_CH_LAYOUT_MONO:
188  case AV_CH_LAYOUT_2_1:
190  if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
191  do {
192 #if HAVE_BIGENDIAN
193  bytestream2_get_buffer(&gb, dst16, avctx->channels * 2);
194  dst16 += avctx->channels;
195 #else
196  channel = avctx->channels;
197  do {
198  *dst16++ = bytestream2_get_be16u(&gb);
199  } while (--channel);
200 #endif
201  bytestream2_skip(&gb, 2);
202  } while (--samples);
203  } else {
204  do {
205  channel = avctx->channels;
206  do {
207  *dst32++ = bytestream2_get_be24u(&gb) << 8;
208  } while (--channel);
209  bytestream2_skip(&gb, 3);
210  } while (--samples);
211  }
212  break;
213  /* remapping: L, R, C, LBack, RBack, LF */
215  if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
216  do {
217  dst16[0] = bytestream2_get_be16u(&gb);
218  dst16[1] = bytestream2_get_be16u(&gb);
219  dst16[2] = bytestream2_get_be16u(&gb);
220  dst16[4] = bytestream2_get_be16u(&gb);
221  dst16[5] = bytestream2_get_be16u(&gb);
222  dst16[3] = bytestream2_get_be16u(&gb);
223  dst16 += 6;
224  } while (--samples);
225  } else {
226  do {
227  dst32[0] = bytestream2_get_be24u(&gb) << 8;
228  dst32[1] = bytestream2_get_be24u(&gb) << 8;
229  dst32[2] = bytestream2_get_be24u(&gb) << 8;
230  dst32[4] = bytestream2_get_be24u(&gb) << 8;
231  dst32[5] = bytestream2_get_be24u(&gb) << 8;
232  dst32[3] = bytestream2_get_be24u(&gb) << 8;
233  dst32 += 6;
234  } while (--samples);
235  }
236  break;
237  /* remapping: L, R, C, LSide, LBack, RBack, RSide, <unused> */
239  if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
240  do {
241  dst16[0] = bytestream2_get_be16u(&gb);
242  dst16[1] = bytestream2_get_be16u(&gb);
243  dst16[2] = bytestream2_get_be16u(&gb);
244  dst16[5] = bytestream2_get_be16u(&gb);
245  dst16[3] = bytestream2_get_be16u(&gb);
246  dst16[4] = bytestream2_get_be16u(&gb);
247  dst16[6] = bytestream2_get_be16u(&gb);
248  dst16 += 7;
249  bytestream2_skip(&gb, 2);
250  } while (--samples);
251  } else {
252  do {
253  dst32[0] = bytestream2_get_be24u(&gb) << 8;
254  dst32[1] = bytestream2_get_be24u(&gb) << 8;
255  dst32[2] = bytestream2_get_be24u(&gb) << 8;
256  dst32[5] = bytestream2_get_be24u(&gb) << 8;
257  dst32[3] = bytestream2_get_be24u(&gb) << 8;
258  dst32[4] = bytestream2_get_be24u(&gb) << 8;
259  dst32[6] = bytestream2_get_be24u(&gb) << 8;
260  dst32 += 7;
261  bytestream2_skip(&gb, 3);
262  } while (--samples);
263  }
264  break;
265  /* remapping: L, R, C, LSide, LBack, RBack, RSide, LF */
267  if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
268  do {
269  dst16[0] = bytestream2_get_be16u(&gb);
270  dst16[1] = bytestream2_get_be16u(&gb);
271  dst16[2] = bytestream2_get_be16u(&gb);
272  dst16[6] = bytestream2_get_be16u(&gb);
273  dst16[4] = bytestream2_get_be16u(&gb);
274  dst16[5] = bytestream2_get_be16u(&gb);
275  dst16[7] = bytestream2_get_be16u(&gb);
276  dst16[3] = bytestream2_get_be16u(&gb);
277  dst16 += 8;
278  } while (--samples);
279  } else {
280  do {
281  dst32[0] = bytestream2_get_be24u(&gb) << 8;
282  dst32[1] = bytestream2_get_be24u(&gb) << 8;
283  dst32[2] = bytestream2_get_be24u(&gb) << 8;
284  dst32[6] = bytestream2_get_be24u(&gb) << 8;
285  dst32[4] = bytestream2_get_be24u(&gb) << 8;
286  dst32[5] = bytestream2_get_be24u(&gb) << 8;
287  dst32[7] = bytestream2_get_be24u(&gb) << 8;
288  dst32[3] = bytestream2_get_be24u(&gb) << 8;
289  dst32 += 8;
290  } while (--samples);
291  }
292  break;
293  }
294  }
295 
296  *got_frame_ptr = 1;
297 
298  retval = bytestream2_tell(&gb);
299  if (avctx->debug & FF_DEBUG_BITSTREAM)
300  av_dlog(avctx, "pcm_bluray_decode_frame: decoded %d -> %d bytes\n",
301  retval, buf_size);
302  return retval + 4;
303 }
304 
306  .name = "pcm_bluray",
307  .long_name = NULL_IF_CONFIG_SMALL("PCM signed 16|20|24-bit big-endian for Blu-ray media"),
308  .type = AVMEDIA_TYPE_AUDIO,
310  .decode = pcm_bluray_decode_frame,
311  .capabilities = CODEC_CAP_DR1,
312  .sample_fmts = (const enum AVSampleFormat[]){
314  },
315 };
#define AV_CH_LAYOUT_7POINT1
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
This structure describes decoded (raw) audio or video data.
Definition: frame.h:135
AVCodec ff_pcm_bluray_decoder
Definition: pcm-bluray.c:305
#define AV_CH_LAYOUT_SURROUND
#define FF_DEBUG_BITSTREAM
Definition: avcodec.h:2381
int size
Definition: avcodec.h:974
static int pcm_bluray_parse_header(AVCodecContext *avctx, const uint8_t *header)
Parse the header of a LPCM frame read from a Blu-ray MPEG-TS stream.
Definition: pcm-bluray.c:53
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:132
#define AV_CH_LAYOUT_4POINT0
#define AV_CH_LAYOUT_7POINT0
av_dlog(ac->avr,"%d samples - audio_convert: %s to %s (%s)\n", 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:2530
#define AV_CH_LAYOUT_STEREO
AVCodec.
Definition: avcodec.h:2812
#define AV_CH_LAYOUT_5POINT0
#define FFALIGN(x, a)
Definition: common.h:62
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1815
uint8_t
#define FF_DEBUG_PICT_INFO
Definition: avcodec.h:2379
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:684
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:973
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2523
signed 32 bits
Definition: samplefmt.h:65
#define AV_CH_LAYOUT_5POINT1
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:161
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:145
static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g, uint8_t *dst, unsigned int size)
Definition: bytestream.h:260
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:169
const char * name
Name of the codec implementation.
Definition: avcodec.h:2819
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:1868
#define AV_CH_LAYOUT_2_1
#define AV_CH_LAYOUT_2_2
int bit_rate
the average bitrate
Definition: avcodec.h:1114
audio channel layout utility functions
int32_t
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:185
Libavcodec external API header.
AVSampleFormat
Audio Sample Formats.
Definition: samplefmt.h:61
AV_SAMPLE_FMT_NONE
Definition: avconv_filter.c:68
int sample_rate
samples per second
Definition: avcodec.h:1807
int debug
debug
Definition: avcodec.h:2378
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
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 int pcm_bluray_decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
Definition: pcm-bluray.c:125
int channels
number of audio channels
Definition: avcodec.h:1808
#define AV_CH_LAYOUT_MONO
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