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, "non_pcm_mode"},
215  {"copy" , "Pass NON-PCM through unchanged" , 0, AV_OPT_TYPE_CONST, {.i64 = 0}, 0, 3, FLAGS, "non_pcm_mode"},
216  {"drop" , "Drop NON-PCM" , 0, AV_OPT_TYPE_CONST, {.i64 = 1}, 0, 3, FLAGS, "non_pcm_mode"},
217  {"decode_copy" , "Decode if possible else passthrough", 0, AV_OPT_TYPE_CONST, {.i64 = 2}, 0, 3, FLAGS, "non_pcm_mode"},
218  {"decode_drop" , "Decode if possible else drop" , 0, AV_OPT_TYPE_CONST, {.i64 = 3}, 0, 3, FLAGS, "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:369
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1007
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
AVPacket::data
uint8_t * data
Definition: packet.h:374
AVOption
AVOption.
Definition: opt.h:251
ff_reverse
const uint8_t ff_reverse[256]
Definition: reverse.c:23
FFCodec
Definition: codec_internal.h:119
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:306
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:311
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:123
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:2059
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:352
FLAGS
#define FLAGS
Definition: s302m.c:212
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:298
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
frame_size
int frame_size
Definition: mxfenc.c:2202
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
FF_ENABLE_DEPRECATION_WARNINGS 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:391
AV_CH_LAYOUT_STEREO_DOWNMIX
#define AV_CH_LAYOUT_STEREO_DOWNMIX
Definition: channel_layout.h:239
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:1451
channels
channels
Definition: aptx.h:31
decode.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:264
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:448
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:109
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1450
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:375
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:301
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:1023
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:223
log.h
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AV_CHANNEL_LAYOUT_QUAD
#define AV_CHANNEL_LAYOUT_QUAD
Definition: channel_layout.h:377
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:211
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
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
AVCodecContext
main external API structure.
Definition: avcodec.h:398
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:632
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:425
AVPacket
This structure stores compressed data.
Definition: packet.h:351
AV_CHANNEL_LAYOUT_5POINT1_BACK
#define AV_CHANNEL_LAYOUT_5POINT1_BACK
Definition: channel_layout.h:381
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