FFmpeg: libavformat/adtsenc.c Source File

FFmpeg
adtsenc.c
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1 /*
2  * ADTS muxer.
3  * Copyright (c) 2006 Baptiste Coudurier <baptiste.coudurier@smartjog.com>
4  * Mans Rullgard <mans@mansr.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 
23 #include "libavcodec/get_bits.h"
24 #include "libavcodec/put_bits.h"
25 #include "libavcodec/avcodec.h"
26 #include "libavcodec/mpeg4audio.h"
27 #include "libavutil/opt.h"
28 #include "avformat.h"
29 #include "apetag.h"
30 #include "id3v2.h"
31 
32  #define ADTS_HEADER_SIZE 7
33 
34  typedef struct ADTSContext {
35   AVClass *class;
36   int write_adts;
37   int objecttype;
38   int sample_rate_index;
39   int channel_conf;
40   int pce_size;
41   int apetag;
42   int id3v2tag;
43   uint8_t pce_data[MAX_PCE_SIZE];
44 } ADTSContext;
45 
46  #define ADTS_MAX_FRAME_BYTES ((1 << 13) - 1)
47 
48  static int adts_decode_extradata(AVFormatContext *s, ADTSContext *adts, const uint8_t *buf, int size)
49 {
50  GetBitContext gb;
51  PutBitContext pb;
52  MPEG4AudioConfig m4ac;
53  int off;
54 
55  init_get_bits(&gb, buf, size * 8);
56  off = avpriv_mpeg4audio_get_config(&m4ac, buf, size * 8, 1);
57  if (off < 0)
58  return off;
59  skip_bits_long(&gb, off);
60  adts->objecttype = m4ac.object_type - 1;
61  adts->sample_rate_index = m4ac.sampling_index;
62  adts->channel_conf = m4ac.chan_config;
63 
64  if (adts->objecttype > 3U) {
65  av_log(s, AV_LOG_ERROR, "MPEG-4 AOT %d is not allowed in ADTS\n", adts->objecttype+1);
66  return AVERROR_INVALIDDATA;
67  }
68  if (adts->sample_rate_index == 15) {
69  av_log(s, AV_LOG_ERROR, "Escape sample rate index illegal in ADTS\n");
70  return AVERROR_INVALIDDATA;
71  }
72  if (get_bits(&gb, 1)) {
73  av_log(s, AV_LOG_ERROR, "960/120 MDCT window is not allowed in ADTS\n");
74  return AVERROR_INVALIDDATA;
75  }
76  if (get_bits(&gb, 1)) {
77  av_log(s, AV_LOG_ERROR, "Scalable configurations are not allowed in ADTS\n");
78  return AVERROR_INVALIDDATA;
79  }
80  if (get_bits(&gb, 1)) {
81  av_log(s, AV_LOG_ERROR, "Extension flag is not allowed in ADTS\n");
82  return AVERROR_INVALIDDATA;
83  }
84  if (!adts->channel_conf) {
85  init_put_bits(&pb, adts->pce_data, MAX_PCE_SIZE);
86 
87  put_bits(&pb, 3, 5); //ID_PCE
88  adts->pce_size = (ff_copy_pce_data(&pb, &gb) + 3) / 8;
89  flush_put_bits(&pb);
90  }
91 
92  adts->write_adts = 1;
93 
94  return 0;
95 }
96 
97  static int adts_init(AVFormatContext *s)
98 {
99  ADTSContext *adts = s->priv_data;
100  AVCodecParameters *par = s->streams[0]->codecpar;
101 
102  if (par->codec_id != AV_CODEC_ID_AAC) {
103  av_log(s, AV_LOG_ERROR, "Only AAC streams can be muxed by the ADTS muxer\n");
104  return AVERROR(EINVAL);
105  }
106  if (par->extradata_size > 0)
107  return adts_decode_extradata(s, adts, par->extradata,
108  par->extradata_size);
109 
110  return 0;
111 }
112 
113  static int adts_write_header(AVFormatContext *s)
114 {
115  ADTSContext *adts = s->priv_data;
116 
117  if (adts->id3v2tag)
118  ff_id3v2_write_simple(s, 4, ID3v2_DEFAULT_MAGIC);
119 
120  return 0;
121 }
122 
123  static int adts_write_frame_header(ADTSContext *ctx,
124  uint8_t *buf, int size, int pce_size)
125 {
126  PutBitContext pb;
127 
128  unsigned full_frame_size = (unsigned)ADTS_HEADER_SIZE + size + pce_size;
129  if (full_frame_size > ADTS_MAX_FRAME_BYTES) {
130  av_log(NULL, AV_LOG_ERROR, "ADTS frame size too large: %u (max %d)\n",
131  full_frame_size, ADTS_MAX_FRAME_BYTES);
132  return AVERROR_INVALIDDATA;
133  }
134 
135  init_put_bits(&pb, buf, ADTS_HEADER_SIZE);
136 
137  /* adts_fixed_header */
138  put_bits(&pb, 12, 0xfff); /* syncword */
139  put_bits(&pb, 1, 0); /* ID */
140  put_bits(&pb, 2, 0); /* layer */
141  put_bits(&pb, 1, 1); /* protection_absent */
142  put_bits(&pb, 2, ctx->objecttype); /* profile_objecttype */
143  put_bits(&pb, 4, ctx->sample_rate_index);
144  put_bits(&pb, 1, 0); /* private_bit */
145  put_bits(&pb, 3, ctx->channel_conf); /* channel_configuration */
146  put_bits(&pb, 1, 0); /* original_copy */
147  put_bits(&pb, 1, 0); /* home */
148 
149  /* adts_variable_header */
150  put_bits(&pb, 1, 0); /* copyright_identification_bit */
151  put_bits(&pb, 1, 0); /* copyright_identification_start */
152  put_bits(&pb, 13, full_frame_size); /* aac_frame_length */
153  put_bits(&pb, 11, 0x7ff); /* adts_buffer_fullness */
154  put_bits(&pb, 2, 0); /* number_of_raw_data_blocks_in_frame */
155 
156  flush_put_bits(&pb);
157 
158  return 0;
159 }
160 
161  static int adts_write_packet(AVFormatContext *s, AVPacket *pkt)
162 {
163  ADTSContext *adts = s->priv_data;
164  AVCodecParameters *par = s->streams[0]->codecpar;
165  AVIOContext *pb = s->pb;
166  uint8_t buf[ADTS_HEADER_SIZE];
167 
168  if (!pkt->size)
169  return 0;
170  if (!par->extradata_size) {
171  uint8_t *side_data;
172  int side_data_size = 0, ret;
173 
174  side_data = av_packet_get_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA,
175  &side_data_size);
176  if (side_data_size) {
177  ret = adts_decode_extradata(s, adts, side_data, side_data_size);
178  if (ret < 0)
179  return ret;
180  ret = ff_alloc_extradata(par, side_data_size);
181  if (ret < 0)
182  return ret;
183  memcpy(par->extradata, side_data, side_data_size);
184  }
185  }
186  if (adts->write_adts) {
187  int err = adts_write_frame_header(adts, buf, pkt->size,
188  adts->pce_size);
189  if (err < 0)
190  return err;
191  avio_write(pb, buf, ADTS_HEADER_SIZE);
192  if (adts->pce_size) {
193  avio_write(pb, adts->pce_data, adts->pce_size);
194  adts->pce_size = 0;
195  }
196  }
197  avio_write(pb, pkt->data, pkt->size);
198 
199  return 0;
200 }
201 
202  static int adts_write_trailer(AVFormatContext *s)
203 {
204  ADTSContext *adts = s->priv_data;
205 
206  if (adts->apetag)
207  ff_ape_write_tag(s);
208 
209  return 0;
210 }
211 
212  #define ENC AV_OPT_FLAG_ENCODING_PARAM
213  #define OFFSET(obj) offsetof(ADTSContext, obj)
214  static const AVOption options[] = {
215  { "write_id3v2", "Enable ID3v2 tag writing", OFFSET(id3v2tag), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, ENC},
216  { "write_apetag", "Enable APE tag writing", OFFSET(apetag), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, ENC},
217  { NULL },
218 };
219 
220  static const AVClass adts_muxer_class = {
221  .class_name = "ADTS muxer",
222  .item_name = av_default_item_name,
223  .option = options,
224  .version = LIBAVUTIL_VERSION_INT,
225 };
226 
227  AVOutputFormat ff_adts_muxer = {
228  .name = "adts",
229  .long_name = NULL_IF_CONFIG_SMALL("ADTS AAC (Advanced Audio Coding)"),
230  .mime_type = "audio/aac",
231  .extensions = "aac,adts",
232  .priv_data_size = sizeof(ADTSContext),
233  .audio_codec = AV_CODEC_ID_AAC,
234  .video_codec = AV_CODEC_ID_NONE,
235  .init = adts_init,
236  .write_header = adts_write_header,
237  .write_packet = adts_write_packet,
238  .write_trailer = adts_write_trailer,
239  .priv_class = &adts_muxer_class,
240  .flags = AVFMT_NOTIMESTAMPS,
241 };
ADTSContext::pce_data
uint8_t pce_data[MAX_PCE_SIZE]
Definition: adtsenc.c:43
write_packet
static void write_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost, int unqueue)
Definition: ffmpeg.c:679
NULL
#define NULL
Definition: coverity.c:32
ADTSContext::id3v2tag
int id3v2tag
Definition: adtsenc.c:42
s
const char * s
Definition: avisynth_c.h:768
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AV_CODEC_ID_NONE
Definition: avcodec.h:216
AVOption
AVOption.
Definition: opt.h:246
ff_id3v2_write_simple
int ff_id3v2_write_simple(struct AVFormatContext *s, int id3v2_version, const char *magic)
Write an ID3v2 tag containing all global metadata from s.
Definition: id3v2enc.c:410
put_bits
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:207
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:269
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
skip_bits_long
static void skip_bits_long(GetBitContext *s, int n)
Skips the specified number of bits.
Definition: get_bits.h:212
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
adts_init
static int adts_init(AVFormatContext *s)
Definition: adtsenc.c:97
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
AVPacket::size
int size
Definition: avcodec.h:1431
ID3v2_DEFAULT_MAGIC
#define ID3v2_DEFAULT_MAGIC
Default magic bytes for ID3v2 header: "ID3".
Definition: id3v2.h:35
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
adts_decode_extradata
static int adts_decode_extradata(AVFormatContext *s, ADTSContext *adts, const uint8_t *buf, int size)
Definition: adtsenc.c:48
ADTSContext::objecttype
int objecttype
Definition: adtsenc.c:37
ADTS_MAX_FRAME_BYTES
#define ADTS_MAX_FRAME_BYTES
Definition: adtsenc.c:46
pkt
static AVPacket pkt
Definition: demuxing_decoding.c:54
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3876
adts_write_packet
static int adts_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: adtsenc.c:161
AVFormatContext
Format I/O context.
Definition: avformat.h:1342
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:72
uint8_t
uint8_t
Definition: audio_convert.c:194
options
static const AVOption options[]
Definition: adtsenc.c:214
opt.h
AVOptions.
adts_write_header
static int adts_write_header(AVFormatContext *s)
Definition: adtsenc.c:113
AV_CODEC_ID_AAC
Definition: avcodec.h:553
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1410
AVPacket::data
uint8_t * data
Definition: avcodec.h:1430
ADTS_HEADER_SIZE
#define ADTS_HEADER_SIZE
Definition: adtsenc.c:32
flags
static int flags
Definition: log.c:55
get_bits.h
bitstream reader API header.
size
ptrdiff_t size
Definition: opengl_enc.c:101
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:218
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
U
#define U(x)
Definition: vp56_arith.h:37
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AVERROR
#define AVERROR(e)
Definition: error.h:43
av_packet_get_side_data
uint8_t * av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:350
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
ADTSContext::channel_conf
int channel_conf
Definition: adtsenc.c:39
ADTSContext::write_adts
int write_adts
Definition: adtsenc.c:36
ADTSContext::sample_rate_index
int sample_rate_index
Definition: adtsenc.c:38
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: avcodec.h:3902
ENC
#define ENC
Definition: adtsenc.c:212
ff_alloc_extradata
int ff_alloc_extradata(AVCodecParameters *par, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:3280
write_trailer
static int write_trailer(AVFormatContext *s1)
Definition: v4l2enc.c:94
AVOutputFormat::name
const char * name
Definition: avformat.h:507
ctx
AVFormatContext * ctx
Definition: movenc.c:48
AV_OPT_TYPE_BOOL
Definition: opt.h:240
ADTSContext::pce_size
int pce_size
Definition: adtsenc.c:40
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:469
MPEG4AudioConfig::sampling_index
int sampling_index
Definition: mpeg4audio.h:35
AV_PKT_DATA_NEW_EXTRADATA
The AV_PKT_DATA_NEW_EXTRADATA is used to notify the codec or the format that the extradata buffer was...
Definition: avcodec.h:1158
avcodec.h
Libavcodec external API header.
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1384
buf
void * buf
Definition: avisynth_c.h:690
ff_ape_write_tag
int ff_ape_write_tag(AVFormatContext *s)
Write an APE tag into a file.
Definition: apetag.c:185
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:67
ff_copy_pce_data
static int ff_copy_pce_data(PutBitContext *pb, GetBitContext *gb)
Definition: mpeg4audio.h:131
init_get_bits
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:433
ADTSContext::apetag
int apetag
Definition: adtsenc.c:41
adts_muxer_class
static const AVClass adts_muxer_class
Definition: adtsenc.c:220
avformat.h
Main libavformat public API header.
flush_put_bits
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:101
adts_write_frame_header
static int adts_write_frame_header(ADTSContext *ctx, uint8_t *buf, int size, int pce_size)
Definition: adtsenc.c:123
init_put_bits
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:48
MAX_PCE_SIZE
#define MAX_PCE_SIZE
Maximum size of a PCE including the 3-bit ID_PCE.
Definition: mpeg4audio.h:119
avpriv_mpeg4audio_get_config
int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, int bit_size, int sync_extension)
Parse MPEG-4 systems extradata from a raw buffer to retrieve audio configuration. ...
Definition: mpeg4audio.c:155
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1370
write_header
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:337
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3898
OFFSET
#define OFFSET(obj)
Definition: adtsenc.c:213
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1407
ff_adts_muxer
AVOutputFormat ff_adts_muxer
Definition: adtsenc.c:227
adts_write_trailer
static int adts_write_trailer(AVFormatContext *s)
Definition: adtsenc.c:202
put_bits.h
bitstream writer API
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