FFmpeg
s302m.c
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1 /*
2  * SMPTE 302M decoder
3  * Copyright (c) 2008 Laurent Aimar <fenrir@videolan.org>
4  * Copyright (c) 2009 Baptiste Coudurier <baptiste.coudurier@gmail.com>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
24 #include "libavutil/intreadwrite.h"
25 #include "libavutil/opt.h"
26 #include "libavutil/log.h"
27 #include "libavutil/reverse.h"
28 #include "avcodec.h"
29 #include "codec_internal.h"
30 #include "decode.h"
31 
32 #define AES3_HEADER_LEN 4
33 
34 typedef struct S302Context {
35  AVClass *class;
37 } S302Context;
38 
39 static int s302m_parse_frame_header(AVCodecContext *avctx, const uint8_t *buf,
40  int buf_size)
41 {
42  uint32_t h;
43  int frame_size, channels, bits;
44 
45  if (buf_size <= AES3_HEADER_LEN) {
46  av_log(avctx, AV_LOG_ERROR, "frame is too short\n");
47  return AVERROR_INVALIDDATA;
48  }
49 
50  /*
51  * AES3 header :
52  * size: 16
53  * number channels 2
54  * channel_id 8
55  * bits per samples 2
56  * alignments 4
57  */
58 
59  h = AV_RB32(buf);
60  frame_size = (h >> 16) & 0xffff;
61  channels = ((h >> 14) & 0x0003) * 2 + 2;
62  bits = ((h >> 4) & 0x0003) * 4 + 16;
63 
64  if (AES3_HEADER_LEN + frame_size != buf_size || bits > 24) {
65  av_log(avctx, AV_LOG_ERROR, "frame has invalid header\n");
66  return AVERROR_INVALIDDATA;
67  }
68 
69  /* Set output properties */
70  avctx->bits_per_raw_sample = bits;
71  if (bits > 16)
73  else
75 
77  switch(channels) {
78  case 2:
80  break;
81  case 4:
83  break;
84  case 6:
86  break;
87  case 8:
90  break;
91  default:
94  break;
95  }
96 
97  return frame_size;
98 }
99 
101  int *got_frame_ptr, AVPacket *avpkt)
102 {
103  S302Context *s = avctx->priv_data;
104  const uint8_t *buf = avpkt->data;
105  int buf_size = avpkt->size;
106  int block_size, ret, channels;
107  int i;
108  int non_pcm_data_type = -1;
109 
110  int frame_size = s302m_parse_frame_header(avctx, buf, buf_size);
111  if (frame_size < 0)
112  return frame_size;
113 
114  buf_size -= AES3_HEADER_LEN;
115  buf += AES3_HEADER_LEN;
116 
117  /* get output buffer */
118  block_size = (avctx->bits_per_raw_sample + 4) / 4;
119  channels = avctx->ch_layout.nb_channels;
120  frame->nb_samples = 2 * (buf_size / block_size) / channels;
121  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
122  return ret;
123 
124  avctx->bit_rate = 48000 * channels * (avctx->bits_per_raw_sample + 4) +
125  32 * 48000 / frame->nb_samples;
126  buf_size = (frame->nb_samples * channels / 2) * block_size;
127 
128  if (avctx->bits_per_raw_sample == 24) {
129  uint32_t *o = (uint32_t *)frame->data[0];
130  for (; buf_size > 6; buf_size -= 7) {
131  *o++ = ((unsigned)ff_reverse[buf[2]] << 24) |
132  (ff_reverse[buf[1]] << 16) |
133  (ff_reverse[buf[0]] << 8);
134  *o++ = ((unsigned)ff_reverse[buf[6] & 0xf0] << 28) |
135  (ff_reverse[buf[5]] << 20) |
136  (ff_reverse[buf[4]] << 12) |
137  (ff_reverse[buf[3] & 0x0f] << 4);
138  buf += 7;
139  }
140  o = (uint32_t *)frame->data[0];
141  if (channels == 2)
142  for (i=0; i<frame->nb_samples * 2 - 6; i+=2) {
143  if (o[i] || o[i+1] || o[i+2] || o[i+3])
144  break;
145  if (o[i+4] == 0x96F87200U && o[i+5] == 0xA54E1F00) {
146  non_pcm_data_type = (o[i+6] >> 16) & 0x1F;
147  break;
148  }
149  }
150  } else if (avctx->bits_per_raw_sample == 20) {
151  uint32_t *o = (uint32_t *)frame->data[0];
152  for (; buf_size > 5; buf_size -= 6) {
153  *o++ = ((unsigned)ff_reverse[buf[2] & 0xf0] << 28) |
154  (ff_reverse[buf[1]] << 20) |
155  (ff_reverse[buf[0]] << 12);
156  *o++ = ((unsigned)ff_reverse[buf[5] & 0xf0] << 28) |
157  (ff_reverse[buf[4]] << 20) |
158  (ff_reverse[buf[3]] << 12);
159  buf += 6;
160  }
161  o = (uint32_t *)frame->data[0];
162  if (channels == 2)
163  for (i=0; i<frame->nb_samples * 2 - 6; i+=2) {
164  if (o[i] || o[i+1] || o[i+2] || o[i+3])
165  break;
166  if (o[i+4] == 0x6F872000U && o[i+5] == 0x54E1F000) {
167  non_pcm_data_type = (o[i+6] >> 16) & 0x1F;
168  break;
169  }
170  }
171  } else {
172  uint16_t *o = (uint16_t *)frame->data[0];
173  for (; buf_size > 4; buf_size -= 5) {
174  *o++ = (ff_reverse[buf[1]] << 8) |
175  ff_reverse[buf[0]];
176  *o++ = (ff_reverse[buf[4] & 0xf0] << 12) |
177  (ff_reverse[buf[3]] << 4) |
178  (ff_reverse[buf[2]] >> 4);
179  buf += 5;
180  }
181  o = (uint16_t *)frame->data[0];
182  if (channels == 2)
183  for (i=0; i<frame->nb_samples * 2 - 6; i+=2) {
184  if (o[i] || o[i+1] || o[i+2] || o[i+3])
185  break;
186  if (o[i+4] == 0xF872U && o[i+5] == 0x4E1F) {
187  non_pcm_data_type = (o[i+6] & 0x1F);
188  break;
189  }
190  }
191  }
192 
193  if (non_pcm_data_type != -1) {
194  if (s->non_pcm_mode == 3) {
195  av_log(avctx, AV_LOG_ERROR,
196  "S302 non PCM mode with data type %d not supported\n",
197  non_pcm_data_type);
198  return AVERROR_PATCHWELCOME;
199  }
200  if (s->non_pcm_mode & 1) {
201  return avpkt->size;
202  }
203  }
204 
205  avctx->sample_rate = 48000;
206 
207  *got_frame_ptr = 1;
208 
209  return avpkt->size;
210 }
211 
212 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_DECODING_PARAM
213 static const AVOption s302m_options[] = {
214  {"non_pcm_mode", "Chooses what to do with NON-PCM", offsetof(S302Context, non_pcm_mode), AV_OPT_TYPE_INT, {.i64 = 3}, 0, 3, FLAGS, .unit = "non_pcm_mode"},
215  {"copy" , "Pass NON-PCM through unchanged" , 0, AV_OPT_TYPE_CONST, {.i64 = 0}, 0, 3, FLAGS, .unit = "non_pcm_mode"},
216  {"drop" , "Drop NON-PCM" , 0, AV_OPT_TYPE_CONST, {.i64 = 1}, 0, 3, FLAGS, .unit = "non_pcm_mode"},
217  {"decode_copy" , "Decode if possible else passthrough", 0, AV_OPT_TYPE_CONST, {.i64 = 2}, 0, 3, FLAGS, .unit = "non_pcm_mode"},
218  {"decode_drop" , "Decode if possible else drop" , 0, AV_OPT_TYPE_CONST, {.i64 = 3}, 0, 3, FLAGS, .unit = "non_pcm_mode"},
219  {NULL}
220 };
221 
222 static const AVClass s302m_class = {
223  .class_name = "SMPTE 302M Decoder",
224  .item_name = av_default_item_name,
225  .option = s302m_options,
226  .version = LIBAVUTIL_VERSION_INT,
227 };
228 
230  .p.name = "s302m",
231  CODEC_LONG_NAME("SMPTE 302M"),
232  .p.type = AVMEDIA_TYPE_AUDIO,
233  .p.id = AV_CODEC_ID_S302M,
234  .p.priv_class = &s302m_class,
235  .priv_data_size = sizeof(S302Context),
237  .p.capabilities = AV_CODEC_CAP_CHANNEL_CONF |
239 };
opt.h
AV_CHANNEL_LAYOUT_STEREO
#define AV_CHANNEL_LAYOUT_STEREO
Definition: channel_layout.h:389
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1068
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVPacket::data
uint8_t * data
Definition: packet.h:522
AVOption
AVOption.
Definition: opt.h:294
ff_reverse
const uint8_t ff_reverse[256]
Definition: reverse.c:23
FFCodec
Definition: codec_internal.h:127
AES3_HEADER_LEN
#define AES3_HEADER_LEN
Definition: s302m.c:32
reverse.h
AVChannelLayout::order
enum AVChannelOrder order
Channel order used in this layout.
Definition: channel_layout.h:318
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:323
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:361
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:2111
s302m_class
static const AVClass s302m_class
Definition: s302m.c:222
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AV_CODEC_ID_S302M
@ AV_CODEC_ID_S302M
Definition: codec_id.h:357
FLAGS
#define FLAGS
Definition: s302m.c:212
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:306
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:198
frame_size
int frame_size
Definition: mxfenc.c:2422
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AV_CHANNEL_ORDER_UNSPEC
@ AV_CHANNEL_ORDER_UNSPEC
Only the channel count is specified, without any further information about the channel order.
Definition: channel_layout.h:112
av_channel_layout_from_mask
int av_channel_layout_from_mask(AVChannelLayout *channel_layout, uint64_t mask)
Initialize a native channel layout from a bitmask indicating which channels are present.
Definition: channel_layout.c:421
AV_CH_LAYOUT_STEREO_DOWNMIX
#define AV_CH_LAYOUT_STEREO_DOWNMIX
Definition: channel_layout.h:249
bits
uint8_t bits
Definition: vp3data.h:128
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1521
channels
channels
Definition: aptx.h:31
decode.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:272
frame
static AVFrame * frame
Definition: demux_decode.c:54
if
if(ret)
Definition: filter_design.txt:179
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
S302Context
Definition: s302m.c:34
AVCodecContext::bit_rate
int64_t bit_rate
the average bitrate
Definition: avcodec.h:495
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
ff_s302m_decoder
const FFCodec ff_s302m_decoder
Definition: s302m.c:229
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_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1618
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:523
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:313
codec_internal.h
for
for(k=2;k<=8;++k)
Definition: h264pred_template.c:425
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1084
s302m_decode_frame
static int s302m_decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame_ptr, AVPacket *avpkt)
Definition: s302m.c:100
AV_RB32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:96
S302Context::non_pcm_mode
int non_pcm_mode
Definition: s302m.c:36
AV_CH_LAYOUT_5POINT1_BACK
#define AV_CH_LAYOUT_5POINT1_BACK
Definition: channel_layout.h:227
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:420
log.h
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
AV_CHANNEL_LAYOUT_QUAD
#define AV_CHANNEL_LAYOUT_QUAD
Definition: channel_layout.h:397
AV_SAMPLE_FMT_S16
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:58
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
avcodec.h
ret
ret
Definition: filter_design.txt:187
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:71
AVCodecContext
main external API structure.
Definition: avcodec.h:445
channel_layout.h
s302m_options
static const AVOption s302m_options[]
Definition: s302m.c:213
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:225
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:662
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AV_CHANNEL_LAYOUT_5POINT1_BACK
#define AV_CHANNEL_LAYOUT_5POINT1_BACK
Definition: channel_layout.h:401
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
h
h
Definition: vp9dsp_template.c:2038
AV_SAMPLE_FMT_S32
@ AV_SAMPLE_FMT_S32
signed 32 bits
Definition: samplefmt.h:59
AV_OPT_TYPE_CONST
@ AV_OPT_TYPE_CONST
Definition: opt.h:234
s302m_parse_frame_header
static int s302m_parse_frame_header(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
Definition: s302m.c:39