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/codec_id.h"
26 #include "libavcodec/codec_par.h"
27 #include "libavcodec/packet.h"
28 #include "libavcodec/mpeg4audio.h"
29 #include "libavcodec/mpeg4audio_copy_pce.h"
30 #include "libavutil/opt.h"
31 #include "avformat.h"
32 #include "apetag.h"
33 #include "id3v2.h"
34 #include "mux.h"
35 
36  #define ADTS_HEADER_SIZE 7
37 
38  typedef struct ADTSContext {
39   AVClass *class;
40   int write_adts;
41   int objecttype;
42   int sample_rate_index;
43   int channel_conf;
44   int pce_size;
45   int apetag;
46   int id3v2tag;
47   int mpeg_id;
48   uint8_t pce_data[MAX_PCE_SIZE];
49 } ADTSContext;
50 
51  #define ADTS_MAX_FRAME_BYTES ((1 << 14) - 1)
52 
53  static int adts_decode_extradata(AVFormatContext *s, ADTSContext *adts, const uint8_t *buf, int size)
54 {
55  GetBitContext gb;
56  PutBitContext pb;
57  MPEG4AudioConfig m4ac;
58  int off, ret;
59 
60  ret = init_get_bits8(&gb, buf, size);
61  if (ret < 0)
62  return ret;
63  off = avpriv_mpeg4audio_get_config2(&m4ac, buf, size, 1, s);
64  if (off < 0)
65  return off;
66  skip_bits_long(&gb, off);
67  adts->objecttype = m4ac.object_type - 1;
68  adts->sample_rate_index = m4ac.sampling_index;
69  adts->channel_conf = m4ac.chan_config;
70 
71  if (adts->objecttype > 3U) {
72  av_log(s, AV_LOG_ERROR, "MPEG-4 AOT %d is not allowed in ADTS\n", adts->objecttype+1);
73  return AVERROR_INVALIDDATA;
74  }
75  if (adts->sample_rate_index == 15) {
76  av_log(s, AV_LOG_ERROR, "Escape sample rate index illegal in ADTS\n");
77  return AVERROR_INVALIDDATA;
78  }
79  if (get_bits(&gb, 1)) {
80  av_log(s, AV_LOG_ERROR, "960/120 MDCT window is not allowed in ADTS\n");
81  return AVERROR_INVALIDDATA;
82  }
83  if (get_bits(&gb, 1)) {
84  av_log(s, AV_LOG_ERROR, "Scalable configurations are not allowed in ADTS\n");
85  return AVERROR_INVALIDDATA;
86  }
87  if (get_bits(&gb, 1)) {
88  av_log(s, AV_LOG_ERROR, "Extension flag is not allowed in ADTS\n");
89  return AVERROR_INVALIDDATA;
90  }
91  if (!adts->channel_conf) {
92  init_put_bits(&pb, adts->pce_data, MAX_PCE_SIZE);
93 
94  put_bits(&pb, 3, 5); //ID_PCE
95  adts->pce_size = (ff_copy_pce_data(&pb, &gb) + 3) / 8;
96  flush_put_bits(&pb);
97  }
98 
99  adts->write_adts = 1;
100 
101  return 0;
102 }
103 
104  static int adts_init(AVFormatContext *s)
105 {
106  ADTSContext *adts = s->priv_data;
107  AVCodecParameters *par = s->streams[0]->codecpar;
108 
109  if (par->extradata_size > 0)
110  return adts_decode_extradata(s, adts, par->extradata,
111  par->extradata_size);
112 
113  return 0;
114 }
115 
116  static int adts_write_header(AVFormatContext *s)
117 {
118  ADTSContext *adts = s->priv_data;
119 
120  if (adts->id3v2tag)
121  ff_id3v2_write_simple(s, 4, ID3v2_DEFAULT_MAGIC);
122 
123  return 0;
124 }
125 
126  static int adts_write_frame_header(AVFormatContext *s, ADTSContext *ctx,
127  uint8_t *buf, int size, int pce_size)
128 {
129  PutBitContext pb;
130 
131  unsigned full_frame_size = (unsigned)ADTS_HEADER_SIZE + size + pce_size;
132  if (full_frame_size > ADTS_MAX_FRAME_BYTES) {
133  av_log(s, AV_LOG_ERROR, "frame size too large: %u (max %d)\n",
134  full_frame_size, ADTS_MAX_FRAME_BYTES);
135  return AVERROR_INVALIDDATA;
136  }
137 
138  init_put_bits(&pb, buf, ADTS_HEADER_SIZE);
139 
140  /* adts_fixed_header */
141  put_bits(&pb, 12, 0xfff); /* syncword */
142  put_bits(&pb, 1, ctx->mpeg_id); /* ID */
143  put_bits(&pb, 2, 0); /* layer */
144  put_bits(&pb, 1, 1); /* protection_absent */
145  put_bits(&pb, 2, ctx->objecttype); /* profile_objecttype */
146  put_bits(&pb, 4, ctx->sample_rate_index);
147  put_bits(&pb, 1, 0); /* private_bit */
148  put_bits(&pb, 3, ctx->channel_conf); /* channel_configuration */
149  put_bits(&pb, 1, 0); /* original_copy */
150  put_bits(&pb, 1, 0); /* home */
151 
152  /* adts_variable_header */
153  put_bits(&pb, 1, 0); /* copyright_identification_bit */
154  put_bits(&pb, 1, 0); /* copyright_identification_start */
155  put_bits(&pb, 13, full_frame_size); /* aac_frame_length */
156  put_bits(&pb, 11, 0x7ff); /* adts_buffer_fullness */
157  put_bits(&pb, 2, 0); /* number_of_raw_data_blocks_in_frame */
158 
159  flush_put_bits(&pb);
160 
161  return 0;
162 }
163 
164  static int adts_write_packet(AVFormatContext *s, AVPacket *pkt)
165 {
166  ADTSContext *adts = s->priv_data;
167  AVCodecParameters *par = s->streams[0]->codecpar;
168  AVIOContext *pb = s->pb;
169  uint8_t buf[ADTS_HEADER_SIZE];
170 
171  if (!pkt->size)
172  return 0;
173  if (!par->extradata_size) {
174  uint8_t *side_data;
175  size_t side_data_size;
176  int ret;
177 
178  side_data = av_packet_get_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA,
179  &side_data_size);
180  if (side_data_size) {
181  ret = adts_decode_extradata(s, adts, side_data, side_data_size);
182  if (ret < 0)
183  return ret;
184  ret = ff_alloc_extradata(par, side_data_size);
185  if (ret < 0)
186  return ret;
187  memcpy(par->extradata, side_data, side_data_size);
188  }
189  }
190  if (adts->write_adts) {
191  int err = adts_write_frame_header(s, adts, buf, pkt->size,
192  adts->pce_size);
193  if (err < 0)
194  return err;
195  avio_write(pb, buf, ADTS_HEADER_SIZE);
196  if (adts->pce_size) {
197  avio_write(pb, adts->pce_data, adts->pce_size);
198  adts->pce_size = 0;
199  }
200  }
201  avio_write(pb, pkt->data, pkt->size);
202 
203  return 0;
204 }
205 
206  static int adts_write_trailer(AVFormatContext *s)
207 {
208  ADTSContext *adts = s->priv_data;
209 
210  if (adts->apetag)
211  ff_ape_write_tag(s);
212 
213  return 0;
214 }
215 
216  #define ENC AV_OPT_FLAG_ENCODING_PARAM
217  #define OFFSET(obj) offsetof(ADTSContext, obj)
218  static const AVOption options[] = {
219  { "write_id3v2", "Enable ID3v2 tag writing", OFFSET(id3v2tag), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, ENC},
220  { "write_apetag", "Enable APE tag writing", OFFSET(apetag), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, ENC},
221  { "write_mpeg2", "Set MPEG version to MPEG-2", OFFSET(mpeg_id), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, ENC},
222  { NULL },
223 };
224 
225  static const AVClass adts_muxer_class = {
226  .class_name = "ADTS muxer",
227  .item_name = av_default_item_name,
228  .option = options,
229  .version = LIBAVUTIL_VERSION_INT,
230 };
231 
232  const FFOutputFormat ff_adts_muxer = {
233  .p.name = "adts",
234  .p.long_name = NULL_IF_CONFIG_SMALL("ADTS AAC (Advanced Audio Coding)"),
235  .p.mime_type = "audio/aac",
236  .p.extensions = "aac,adts",
237  .priv_data_size = sizeof(ADTSContext),
238  .p.audio_codec = AV_CODEC_ID_AAC,
239  .p.video_codec = AV_CODEC_ID_NONE,
240  .p.subtitle_codec = AV_CODEC_ID_NONE,
241  .flags_internal = FF_OFMT_FLAG_MAX_ONE_OF_EACH |
242  FF_OFMT_FLAG_ONLY_DEFAULT_CODECS,
243  .init = adts_init,
244  .write_header = adts_write_header,
245  .write_packet = adts_write_packet,
246  .write_trailer = adts_write_trailer,
247  .p.priv_class = &adts_muxer_class,
248  .p.flags = AVFMT_NOTIMESTAMPS,
249 };
skip_bits_long
static void skip_bits_long(GetBitContext *s, int n)
Skips the specified number of bits.
Definition: get_bits.h:278
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:69
adts_write_trailer
static int adts_write_trailer(AVFormatContext *s)
Definition: adtsenc.c:206
AVOutputFormat::name
const char * name
Definition: avformat.h:510
opt.h
adts_init
static int adts_init(AVFormatContext *s)
Definition: adtsenc.c:104
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
AV_PKT_DATA_NEW_EXTRADATA
@ 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: packet.h:56
ADTSContext::apetag
int apetag
Definition: adtsenc.c:45
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:479
adts_decode_extradata
static int adts_decode_extradata(AVFormatContext *s, ADTSContext *adts, const uint8_t *buf, int size)
Definition: adtsenc.c:53
init_put_bits
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:62
id3v2.h
apetag.h
put_bits
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:222
AVPacket::data
uint8_t * data
Definition: packet.h:522
AVOption
AVOption.
Definition: opt.h:346
FF_OFMT_FLAG_ONLY_DEFAULT_CODECS
#define FF_OFMT_FLAG_ONLY_DEFAULT_CODECS
If this flag is set, then the only permitted audio/video/subtitle codec ids are AVOutputFormat....
Definition: mux.h:59
MAX_PCE_SIZE
#define MAX_PCE_SIZE
Maximum size of a PCE including the 3-bit ID_PCE.
Definition: mpeg4audio.h:117
options
static const AVOption options[]
Definition: adtsenc.c:218
FFOutputFormat::p
AVOutputFormat p
The public AVOutputFormat.
Definition: mux.h:65
ADTS_MAX_FRAME_BYTES
#define ADTS_MAX_FRAME_BYTES
Definition: adtsenc.c:51
MPEG4AudioConfig
Definition: mpeg4audio.h:29
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:335
mpeg4audio.h
ADTS_HEADER_SIZE
#define ADTS_HEADER_SIZE
Definition: adtsenc.c:36
adts_write_packet
static int adts_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: adtsenc.c:164
GetBitContext
Definition: get_bits.h:108
adts_write_header
static int adts_write_header(AVFormatContext *s)
Definition: adtsenc.c:116
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
init_get_bits8
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:545
codec_id.h
avpriv_mpeg4audio_get_config2
int avpriv_mpeg4audio_get_config2(MPEG4AudioConfig *c, const uint8_t *buf, int size, int sync_extension, void *logctx)
Parse MPEG-4 systems extradata from a raw buffer to retrieve audio configuration.
Definition: mpeg4audio.c:165
s
#define s(width, name)
Definition: cbs_vp9.c:198
ADTSContext::id3v2tag
int id3v2tag
Definition: adtsenc.c:46
ctx
AVFormatContext * ctx
Definition: movenc.c:48
ff_copy_pce_data
static int ff_copy_pce_data(PutBitContext *pb, GetBitContext *gb)
Definition: mpeg4audio_copy_pce.h:38
get_bits.h
ff_adts_muxer
const FFOutputFormat ff_adts_muxer
Definition: adtsenc.c:232
PutBitContext
Definition: put_bits.h:50
ADTSContext::pce_size
int pce_size
Definition: adtsenc.c:44
ff_ape_write_tag
int ff_ape_write_tag(AVFormatContext *s)
Write an APE tag into a file.
Definition: apetag.c:176
ADTSContext::objecttype
int objecttype
Definition: adtsenc.c:41
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
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
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
MPEG4AudioConfig::sampling_index
int sampling_index
Definition: mpeg4audio.h:31
FFOutputFormat
Definition: mux.h:61
ENC
#define ENC
Definition: adtsenc.c:216
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:73
AV_CODEC_ID_AAC
@ AV_CODEC_ID_AAC
Definition: codec_id.h:442
AVIOContext
Bytestream IO Context.
Definition: avio.h:160
AVPacket::size
int size
Definition: packet.h:523
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:106
ADTSContext::write_adts
int write_adts
Definition: adtsenc.c:40
size
int size
Definition: twinvq_data.h:10344
ID3v2_DEFAULT_MAGIC
#define ID3v2_DEFAULT_MAGIC
Default magic bytes for ID3v2 header: "ID3".
Definition: id3v2.h:35
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:200
ADTSContext::channel_conf
int channel_conf
Definition: adtsenc.c:43
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
packet.h
av_packet_get_side_data
uint8_t * av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type, size_t *size)
Get side information from packet.
Definition: avpacket.c:252
ADTSContext::sample_rate_index
int sample_rate_index
Definition: adtsenc.c:42
FF_OFMT_FLAG_MAX_ONE_OF_EACH
#define FF_OFMT_FLAG_MAX_ONE_OF_EACH
If this flag is set, it indicates that for each codec type whose corresponding default codec (i....
Definition: mux.h:50
MPEG4AudioConfig::chan_config
int chan_config
Definition: mpeg4audio.h:33
adts_write_frame_header
static int adts_write_frame_header(AVFormatContext *s, ADTSContext *ctx, uint8_t *buf, int size, int pce_size)
Definition: adtsenc.c:126
adts_muxer_class
static const AVClass adts_muxer_class
Definition: adtsenc.c:225
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
avformat.h
MPEG4AudioConfig::object_type
int object_type
Definition: mpeg4audio.h:30
U
#define U(x)
Definition: vpx_arith.h:37
ADTSContext::pce_data
uint8_t pce_data[MAX_PCE_SIZE]
Definition: adtsenc.c:48
flush_put_bits
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:143
codec_par.h
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AV_OPT_TYPE_BOOL
@ AV_OPT_TYPE_BOOL
Definition: opt.h:251
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
put_bits.h
OFFSET
#define OFFSET(obj)
Definition: adtsenc.c:217
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:445
mpeg4audio_copy_pce.h
ADTSContext::mpeg_id
int mpeg_id
Definition: adtsenc.c:47
ADTSContext
Definition: adtsenc.c:38
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:239
mux.h
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