FFmpeg
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 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  * PCM codec for Blu-ray PCM audio tracks
25  */
26 
27 #include "libavutil/channel_layout.h"
28 #include "avcodec.h"
29 #include "bytestream.h"
30 #include "codec_internal.h"
31 #include "decode.h"
32 
33 /*
34  * Channel Mapping according to
35  * Blu-ray Disc Read-Only Format Version 1
36  * Part 3: Audio Visual Basic Specifications
37  * mono M1 X
38  * stereo L R
39  * 3/0 L R C X
40  * 2/1 L R S X
41  * 3/1 L R C S
42  * 2/2 L R LS RS
43  * 3/2 L R C LS RS X
44  * 3/2+lfe L R C LS RS lfe
45  * 3/4 L R C LS Rls Rrs RS X
46  * 3/4+lfe L R C LS Rls Rrs RS lfe
47  */
48 
49 /**
50  * Parse the header of a LPCM frame read from a Blu-ray MPEG-TS stream
51  * @param avctx the codec context
52  * @param header pointer to the first four bytes of the data packet
53  */
54 static int pcm_bluray_parse_header(AVCodecContext *avctx,
55  const uint8_t *header)
56 {
57  static const uint8_t bits_per_samples[4] = { 0, 16, 20, 24 };
58  static const AVChannelLayout channel_layouts[16] = {
59  { 0 }, AV_CHANNEL_LAYOUT_MONO, { 0 },
60  AV_CHANNEL_LAYOUT_STEREO, AV_CHANNEL_LAYOUT_SURROUND, AV_CHANNEL_LAYOUT_2_1,
61  AV_CHANNEL_LAYOUT_4POINT0, AV_CHANNEL_LAYOUT_2_2, AV_CHANNEL_LAYOUT_5POINT0,
62  AV_CHANNEL_LAYOUT_5POINT1, AV_CHANNEL_LAYOUT_7POINT0, AV_CHANNEL_LAYOUT_7POINT1,
63  { 0 }, { 0 }, { 0 }, { 0 },
64  };
65  uint8_t channel_layout = header[2] >> 4;
66 
67  if (avctx->debug & FF_DEBUG_PICT_INFO)
68  ff_dlog(avctx, "pcm_bluray_parse_header: header = %02x%02x%02x%02x\n",
69  header[0], header[1], header[2], header[3]);
70 
71  /* get the sample depth and derive the sample format from it */
72  avctx->bits_per_coded_sample = bits_per_samples[header[3] >> 6];
73  if (!(avctx->bits_per_coded_sample == 16 || avctx->bits_per_coded_sample == 24)) {
74  av_log(avctx, AV_LOG_ERROR, "unsupported sample depth (%d)\n", avctx->bits_per_coded_sample);
75  return AVERROR_INVALIDDATA;
76  }
77  avctx->sample_fmt = avctx->bits_per_coded_sample == 16 ? AV_SAMPLE_FMT_S16
78  : AV_SAMPLE_FMT_S32;
79  if (avctx->sample_fmt == AV_SAMPLE_FMT_S32)
80  avctx->bits_per_raw_sample = avctx->bits_per_coded_sample;
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  av_channel_layout_uninit(&avctx->ch_layout);
107  avctx->ch_layout = channel_layouts[channel_layout];
108  if (!avctx->ch_layout.nb_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->ch_layout.nb_channels, 2) * avctx->sample_rate *
115  avctx->bits_per_coded_sample;
116 
117  if (avctx->debug & FF_DEBUG_PICT_INFO)
118  ff_dlog(avctx,
119  "pcm_bluray_parse_header: %d channels, %d bits per sample, %d Hz, %"PRId64" bit/s\n",
120  avctx->ch_layout.nb_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, AVFrame *frame,
126  int *got_frame_ptr, AVPacket *avpkt)
127 {
128  const uint8_t *src = avpkt->data;
129  int buf_size = avpkt->size;
130  GetByteContext gb;
131  int num_source_channels, channel, retval;
132  int sample_size, samples;
133  int16_t *dst16;
134  int32_t *dst32;
135 
136  if (buf_size < 4) {
137  av_log(avctx, AV_LOG_ERROR, "PCM packet too small\n");
138  return AVERROR_INVALIDDATA;
139  }
140 
141  if ((retval = pcm_bluray_parse_header(avctx, src)))
142  return retval;
143  src += 4;
144  buf_size -= 4;
145 
146  bytestream2_init(&gb, src, buf_size);
147 
148  /* There's always an even number of channels in the source */
149  num_source_channels = FFALIGN(avctx->ch_layout.nb_channels, 2);
150  sample_size = (num_source_channels *
151  (avctx->sample_fmt == AV_SAMPLE_FMT_S16 ? 16 : 24)) >> 3;
152  samples = buf_size / sample_size;
153 
154  /* get output buffer */
155  frame->nb_samples = samples;
156  if ((retval = ff_get_buffer(avctx, frame, 0)) < 0)
157  return retval;
158  dst16 = (int16_t *)frame->data[0];
159  dst32 = (int32_t *)frame->data[0];
160 
161  if (samples) {
162  switch (avctx->ch_layout.u.mask) {
163  /* cases with same number of source and coded channels */
164  case AV_CH_LAYOUT_STEREO:
165  case AV_CH_LAYOUT_4POINT0:
166  case AV_CH_LAYOUT_2_2:
167  samples *= num_source_channels;
168  if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
169 #if HAVE_BIGENDIAN
170  bytestream2_get_buffer(&gb, (uint8_t*)dst16, buf_size);
171 #else
172  do {
173  *dst16++ = bytestream2_get_be16u(&gb);
174  } while (--samples);
175 #endif
176  } else {
177  do {
178  *dst32++ = bytestream2_get_be24u(&gb) << 8;
179  } while (--samples);
180  }
181  break;
182  /* cases where number of source channels = coded channels + 1 */
183  case AV_CH_LAYOUT_MONO:
184  case AV_CH_LAYOUT_SURROUND:
185  case AV_CH_LAYOUT_2_1:
186  case AV_CH_LAYOUT_5POINT0:
187  if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
188  do {
189 #if HAVE_BIGENDIAN
190  bytestream2_get_buffer(&gb, (uint8_t*)dst16,
191  avctx->ch_layout.nb_channels * 2);
192  dst16 += avctx->ch_layout.nb_channels;
193 #else
194  channel = avctx->ch_layout.nb_channels;
195  do {
196  *dst16++ = bytestream2_get_be16u(&gb);
197  } while (--channel);
198 #endif
199  bytestream2_skip(&gb, 2);
200  } while (--samples);
201  } else {
202  do {
203  channel = avctx->ch_layout.nb_channels;
204  do {
205  *dst32++ = bytestream2_get_be24u(&gb) << 8;
206  } while (--channel);
207  bytestream2_skip(&gb, 3);
208  } while (--samples);
209  }
210  break;
211  /* remapping: L, R, C, LBack, RBack, LF */
212  case AV_CH_LAYOUT_5POINT1:
213  if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
214  do {
215  dst16[0] = bytestream2_get_be16u(&gb);
216  dst16[1] = bytestream2_get_be16u(&gb);
217  dst16[2] = bytestream2_get_be16u(&gb);
218  dst16[4] = bytestream2_get_be16u(&gb);
219  dst16[5] = bytestream2_get_be16u(&gb);
220  dst16[3] = bytestream2_get_be16u(&gb);
221  dst16 += 6;
222  } while (--samples);
223  } else {
224  do {
225  dst32[0] = bytestream2_get_be24u(&gb) << 8;
226  dst32[1] = bytestream2_get_be24u(&gb) << 8;
227  dst32[2] = bytestream2_get_be24u(&gb) << 8;
228  dst32[4] = bytestream2_get_be24u(&gb) << 8;
229  dst32[5] = bytestream2_get_be24u(&gb) << 8;
230  dst32[3] = bytestream2_get_be24u(&gb) << 8;
231  dst32 += 6;
232  } while (--samples);
233  }
234  break;
235  /* remapping: L, R, C, LSide, LBack, RBack, RSide, <unused> */
236  case AV_CH_LAYOUT_7POINT0:
237  if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
238  do {
239  dst16[0] = bytestream2_get_be16u(&gb);
240  dst16[1] = bytestream2_get_be16u(&gb);
241  dst16[2] = bytestream2_get_be16u(&gb);
242  dst16[5] = bytestream2_get_be16u(&gb);
243  dst16[3] = bytestream2_get_be16u(&gb);
244  dst16[4] = bytestream2_get_be16u(&gb);
245  dst16[6] = bytestream2_get_be16u(&gb);
246  dst16 += 7;
247  bytestream2_skip(&gb, 2);
248  } while (--samples);
249  } else {
250  do {
251  dst32[0] = bytestream2_get_be24u(&gb) << 8;
252  dst32[1] = bytestream2_get_be24u(&gb) << 8;
253  dst32[2] = bytestream2_get_be24u(&gb) << 8;
254  dst32[5] = bytestream2_get_be24u(&gb) << 8;
255  dst32[3] = bytestream2_get_be24u(&gb) << 8;
256  dst32[4] = bytestream2_get_be24u(&gb) << 8;
257  dst32[6] = bytestream2_get_be24u(&gb) << 8;
258  dst32 += 7;
259  bytestream2_skip(&gb, 3);
260  } while (--samples);
261  }
262  break;
263  /* remapping: L, R, C, LSide, LBack, RBack, RSide, LF */
264  case AV_CH_LAYOUT_7POINT1:
265  if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
266  do {
267  dst16[0] = bytestream2_get_be16u(&gb);
268  dst16[1] = bytestream2_get_be16u(&gb);
269  dst16[2] = bytestream2_get_be16u(&gb);
270  dst16[6] = bytestream2_get_be16u(&gb);
271  dst16[4] = bytestream2_get_be16u(&gb);
272  dst16[5] = bytestream2_get_be16u(&gb);
273  dst16[7] = bytestream2_get_be16u(&gb);
274  dst16[3] = bytestream2_get_be16u(&gb);
275  dst16 += 8;
276  } while (--samples);
277  } else {
278  do {
279  dst32[0] = bytestream2_get_be24u(&gb) << 8;
280  dst32[1] = bytestream2_get_be24u(&gb) << 8;
281  dst32[2] = bytestream2_get_be24u(&gb) << 8;
282  dst32[6] = bytestream2_get_be24u(&gb) << 8;
283  dst32[4] = bytestream2_get_be24u(&gb) << 8;
284  dst32[5] = bytestream2_get_be24u(&gb) << 8;
285  dst32[7] = bytestream2_get_be24u(&gb) << 8;
286  dst32[3] = bytestream2_get_be24u(&gb) << 8;
287  dst32 += 8;
288  } while (--samples);
289  }
290  break;
291  }
292  }
293 
294  *got_frame_ptr = 1;
295 
296  retval = bytestream2_tell(&gb);
297  if (avctx->debug & FF_DEBUG_BITSTREAM)
298  ff_dlog(avctx, "pcm_bluray_decode_frame: decoded %d -> %d bytes\n",
299  retval, buf_size);
300  return retval + 4;
301 }
302 
303 const FFCodec ff_pcm_bluray_decoder = {
304  .p.name = "pcm_bluray",
305  CODEC_LONG_NAME("PCM signed 16|20|24-bit big-endian for Blu-ray media"),
306  .p.type = AVMEDIA_TYPE_AUDIO,
307  .p.id = AV_CODEC_ID_PCM_BLURAY,
308  FF_CODEC_DECODE_CB(pcm_bluray_decode_frame),
309  .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_CHANNEL_CONF,
310  .p.sample_fmts = (const enum AVSampleFormat[]){
311  AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_NONE
312  },
313 };
AV_CH_LAYOUT_7POINT0
#define AV_CH_LAYOUT_7POINT0
Definition: channel_layout.h:233
AVChannelLayout::u
union AVChannelLayout::@427 u
Details about which channels are present in this layout.
AV_CODEC_ID_PCM_BLURAY
@ AV_CODEC_ID_PCM_BLURAY
Definition: codec_id.h:358
AV_CHANNEL_LAYOUT_STEREO
#define AV_CHANNEL_LAYOUT_STEREO
Definition: channel_layout.h:387
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1056
ff_pcm_bluray_decoder
const FFCodec ff_pcm_bluray_decoder
Definition: pcm-bluray.c:303
GetByteContext
Definition: bytestream.h:33
AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_MONO
Definition: channel_layout.h:212
AV_CHANNEL_LAYOUT_2_2
#define AV_CHANNEL_LAYOUT_2_2
Definition: channel_layout.h:394
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:389
AVPacket::data
uint8_t * data
Definition: packet.h:539
FFCodec
Definition: codec_internal.h:127
AVChannelLayout::mask
uint64_t mask
This member must be used for AV_CHANNEL_ORDER_NATIVE, and may be used for AV_CHANNEL_ORDER_AMBISONIC ...
Definition: channel_layout.h:343
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:321
FF_DEBUG_PICT_INFO
#define FF_DEBUG_PICT_INFO
Definition: avcodec.h:1407
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:1071
AV_CH_LAYOUT_STEREO
#define AV_CH_LAYOUT_STEREO
Definition: channel_layout.h:213
AV_CHANNEL_LAYOUT_SURROUND
#define AV_CHANNEL_LAYOUT_SURROUND
Definition: channel_layout.h:390
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:209
AV_CHANNEL_LAYOUT_4POINT0
#define AV_CHANNEL_LAYOUT_4POINT0
Definition: channel_layout.h:392
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:311
AV_CHANNEL_LAYOUT_7POINT1
#define AV_CHANNEL_LAYOUT_7POINT1
Definition: channel_layout.h:409
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1585
decode.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:296
AV_CH_LAYOUT_2_1
#define AV_CH_LAYOUT_2_1
Definition: channel_layout.h:215
AVCodecContext::bit_rate
int64_t bit_rate
the average bitrate
Definition: avcodec.h:501
AV_CH_LAYOUT_5POINT1
#define AV_CH_LAYOUT_5POINT1
Definition: channel_layout.h:223
bytestream2_get_buffer
static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g, uint8_t *dst, unsigned int size)
Definition: bytestream.h:267
bytestream2_tell
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:192
AV_CODEC_CAP_CHANNEL_CONF
#define AV_CODEC_CAP_CHANNEL_CONF
Codec should fill in channel configuration and samplerate instead of container.
Definition: codec.h:106
ff_dlog
#define ff_dlog(a,...)
Definition: tableprint_vlc.h:28
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1697
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:540
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:311
codec_internal.h
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1063
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:56
header
static const uint8_t header[24]
Definition: sdr2.c:68
AV_CH_LAYOUT_5POINT0
#define AV_CH_LAYOUT_5POINT0
Definition: channel_layout.h:222
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1578
pcm_bluray_decode_frame
static int pcm_bluray_decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame_ptr, AVPacket *avpkt)
Definition: pcm-bluray.c:125
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
AV_CH_LAYOUT_7POINT1
#define AV_CH_LAYOUT_7POINT1
Definition: channel_layout.h:235
AV_SAMPLE_FMT_S16
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:58
pcm_bluray_parse_header
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:54
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
avcodec.h
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AV_CH_LAYOUT_SURROUND
#define AV_CH_LAYOUT_SURROUND
Definition: channel_layout.h:216
AV_CHANNEL_LAYOUT_7POINT0
#define AV_CHANNEL_LAYOUT_7POINT0
Definition: channel_layout.h:407
AV_CHANNEL_LAYOUT_2_1
#define AV_CHANNEL_LAYOUT_2_1
Definition: channel_layout.h:389
AVCodecContext
main external API structure.
Definition: avcodec.h:451
channel_layout.h
av_channel_layout_uninit
void av_channel_layout_uninit(AVChannelLayout *channel_layout)
Free any allocated data in the channel layout and reset the channel count to 0.
Definition: channel_layout.c:437
samples
Filter the word “frame” indicates either a video frame or a group of audio samples
Definition: filter_design.txt:8
AVCodecContext::debug
int debug
debug
Definition: avcodec.h:1406
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:386
FFALIGN
#define FFALIGN(x, a)
Definition: macros.h:78
AVPacket
This structure stores compressed data.
Definition: packet.h:516
channel_layouts
static const uint16_t channel_layouts[7]
Definition: dca_lbr.c:112
AV_CH_LAYOUT_4POINT0
#define AV_CH_LAYOUT_4POINT0
Definition: channel_layout.h:218
int32_t
int32_t
Definition: audioconvert.c:56
bytestream.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
AV_CHANNEL_LAYOUT_5POINT0
#define AV_CHANNEL_LAYOUT_5POINT0
Definition: channel_layout.h:396
AV_CHANNEL_LAYOUT_5POINT1
#define AV_CHANNEL_LAYOUT_5POINT1
Definition: channel_layout.h:397
FF_DEBUG_BITSTREAM
#define FF_DEBUG_BITSTREAM
Definition: avcodec.h:1409
AV_SAMPLE_FMT_S32
@ AV_SAMPLE_FMT_S32
signed 32 bits
Definition: samplefmt.h:59
AV_CH_LAYOUT_2_2
#define AV_CH_LAYOUT_2_2
Definition: channel_layout.h:220
src
#define src
Definition: vp8dsp.c:248
channel
channel
Definition: ebur128.h:39
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