FFmpeg
aacdec.c
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1 /*
2  * raw ADTS AAC demuxer
3  * Copyright (c) 2008 Michael Niedermayer <michaelni@gmx.at>
4  * Copyright (c) 2009 Robert Swain ( rob opendot cl )
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 "libavutil/avassert.h"
24 #include "libavutil/intreadwrite.h"
25 #include "avformat.h"
26 #include "avio_internal.h"
27 #include "internal.h"
28 #include "id3v1.h"
29 #include "id3v2.h"
30 #include "apetag.h"
31 
32 #define ADTS_HEADER_SIZE 7
33 
34 static int adts_aac_probe(const AVProbeData *p)
35 {
36  int max_frames = 0, first_frames = 0;
37  int fsize, frames;
38  const uint8_t *buf0 = p->buf;
39  const uint8_t *buf2;
40  const uint8_t *buf;
41  const uint8_t *end = buf0 + p->buf_size - 7;
42 
43  buf = buf0;
44 
45  for (; buf < end; buf = buf2 + 1) {
46  buf2 = buf;
47 
48  for (frames = 0; buf2 < end; frames++) {
49  uint32_t header = AV_RB16(buf2);
50  if ((header & 0xFFF6) != 0xFFF0) {
51  if (buf != buf0) {
52  // Found something that isn't an ADTS header, starting
53  // from a position other than the start of the buffer.
54  // Discard the count we've accumulated so far since it
55  // probably was a false positive.
56  frames = 0;
57  }
58  break;
59  }
60  fsize = (AV_RB32(buf2 + 3) >> 13) & 0x1FFF;
61  if (fsize < 7)
62  break;
63  fsize = FFMIN(fsize, end - buf2);
64  buf2 += fsize;
65  }
66  max_frames = FFMAX(max_frames, frames);
67  if (buf == buf0)
68  first_frames = frames;
69  }
70 
71  if (first_frames >= 3)
72  return AVPROBE_SCORE_EXTENSION + 1;
73  else if (max_frames > 100)
75  else if (max_frames >= 3)
76  return AVPROBE_SCORE_EXTENSION / 2;
77  else if (first_frames >= 1)
78  return 1;
79  else
80  return 0;
81 }
82 
84 {
85  AVStream *st;
86  uint16_t state;
87 
88  st = avformat_new_stream(s, NULL);
89  if (!st)
90  return AVERROR(ENOMEM);
91 
95 
96  ff_id3v1_read(s);
97  if ((s->pb->seekable & AVIO_SEEKABLE_NORMAL) &&
99  int64_t cur = avio_tell(s->pb);
100  ff_ape_parse_tag(s);
101  avio_seek(s->pb, cur, SEEK_SET);
102  }
103 
104  // skip data until the first ADTS frame is found
105  state = avio_r8(s->pb);
106  while (!avio_feof(s->pb) && avio_tell(s->pb) < s->probesize) {
107  state = (state << 8) | avio_r8(s->pb);
108  if ((state >> 4) != 0xFFF)
109  continue;
110  avio_seek(s->pb, -2, SEEK_CUR);
111  break;
112  }
113  if ((state >> 4) != 0xFFF)
114  return AVERROR_INVALIDDATA;
115 
116  // LCM of all possible ADTS sample rates
117  avpriv_set_pts_info(st, 64, 1, 28224000);
118 
119  return 0;
120 }
121 
123 {
124  AVDictionary *metadata = NULL;
125  AVIOContext ioctx;
126  ID3v2ExtraMeta *id3v2_extra_meta = NULL;
127  int ret;
128 
129  ret = av_append_packet(s->pb, pkt, ff_id3v2_tag_len(pkt->data) - pkt->size);
130  if (ret < 0) {
131  av_packet_unref(pkt);
132  return ret;
133  }
134 
135  ffio_init_context(&ioctx, pkt->data, pkt->size, 0, NULL, NULL, NULL, NULL);
136  ff_id3v2_read_dict(&ioctx, &metadata, ID3v2_DEFAULT_MAGIC, &id3v2_extra_meta);
137  if ((ret = ff_id3v2_parse_priv_dict(&metadata, &id3v2_extra_meta)) < 0)
138  goto error;
139 
140  if (metadata) {
141  if ((ret = av_dict_copy(&s->metadata, metadata, 0)) < 0)
142  goto error;
144  }
145 
146 error:
147  av_packet_unref(pkt);
148  ff_id3v2_free_extra_meta(&id3v2_extra_meta);
149  av_dict_free(&metadata);
150 
151  return ret;
152 }
153 
155 {
156  int ret, fsize;
157 
158 retry:
159  ret = av_get_packet(s->pb, pkt, ADTS_HEADER_SIZE);
160  if (ret < 0)
161  return ret;
162 
163  if (ret < ADTS_HEADER_SIZE) {
164  av_packet_unref(pkt);
165  return AVERROR(EIO);
166  }
167 
168  if ((AV_RB16(pkt->data) >> 4) != 0xfff) {
169  // Parse all the ID3 headers between frames
171 
172  av_assert2(append > 0);
173  ret = av_append_packet(s->pb, pkt, append);
174  if (ret != append) {
175  av_packet_unref(pkt);
176  return AVERROR(EIO);
177  }
179  av_packet_unref(pkt);
180  return AVERROR_INVALIDDATA;
181  }
182  ret = handle_id3(s, pkt);
183  if (ret < 0)
184  return ret;
185 
186  goto retry;
187  }
188 
189  fsize = (AV_RB32(pkt->data + 3) >> 13) & 0x1FFF;
190  if (fsize < ADTS_HEADER_SIZE) {
191  av_packet_unref(pkt);
192  return AVERROR_INVALIDDATA;
193  }
194 
195  ret = av_append_packet(s->pb, pkt, fsize - pkt->size);
196  if (ret < 0)
197  av_packet_unref(pkt);
198 
199  return ret;
200 }
201 
203  .name = "aac",
204  .long_name = NULL_IF_CONFIG_SMALL("raw ADTS AAC (Advanced Audio Coding)"),
205  .read_probe = adts_aac_probe,
206  .read_header = adts_aac_read_header,
207  .read_packet = adts_aac_read_packet,
208  .flags = AVFMT_GENERIC_INDEX,
209  .extensions = "aac",
210  .mime_type = "audio/aac,audio/aacp,audio/x-aac",
211  .raw_codec_id = AV_CODEC_ID_AAC,
212 };
int64_t probesize
Maximum size of the data read from input for determining the input container format.
Definition: avformat.h:1524
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4882
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3953
void ff_id3v1_read(AVFormatContext *s)
Read an ID3v1 tag.
Definition: id3v1.c:235
int size
Definition: avcodec.h:1478
#define ID3v2_DEFAULT_MAGIC
Default magic bytes for ID3v2 header: "ID3".
Definition: id3v2.h:35
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
int event_flags
Flags for the user to detect events happening on the file.
Definition: avformat.h:1673
int av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags)
Copy entries from one AVDictionary struct into another.
Definition: dict.c:217
static AVPacket pkt
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_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:87
if it could not because there are no more frames
static int adts_aac_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: aacdec.c:154
Format I/O context.
Definition: avformat.h:1358
#define ID3v2_HEADER_SIZE
Definition: id3v2.h:30
uint8_t
#define av_assert2(cond)
assert() equivalent, that does lie in speed critical code.
Definition: avassert.h:64
static int adts_aac_read_header(AVFormatContext *s)
Definition: aacdec.c:83
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
enum AVStreamParseType need_parsing
Definition: avformat.h:1099
int ff_id3v2_parse_priv_dict(AVDictionary **metadata, ID3v2ExtraMeta **extra_meta)
Parse PRIV tags into a dictionary.
Definition: id3v2.c:1234
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4455
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:87
static uint8_t * append(uint8_t *buf, const uint8_t *src, int size)
AVDictionaryEntry * av_dict_get(const AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
Definition: dict.c:40
uint8_t * data
Definition: avcodec.h:1477
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:310
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
static const uint8_t header[24]
Definition: sdr2.c:67
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:804
int av_append_packet(AVIOContext *s, AVPacket *pkt, int size)
Read data and append it to the current content of the AVPacket.
Definition: utils.c:320
#define ADTS_HEADER_SIZE
Definition: aacdec.c:32
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1598
AVInputFormat ff_aac_demuxer
Definition: aacdec.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
ff_const59 struct AVInputFormat * iformat
The input container format.
Definition: avformat.h:1370
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values. ...
Definition: dict.c:203
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3949
void ff_id3v2_free_extra_meta(ID3v2ExtraMeta **extra_meta)
Free memory allocated parsing special (non-text) metadata.
Definition: id3v2.c:1127
simple assert() macros that are a bit more flexible than ISO C assert().
static int adts_aac_probe(const AVProbeData *p)
Definition: aacdec.c:34
#define FFMAX(a, b)
Definition: common.h:94
int64_t ff_ape_parse_tag(AVFormatContext *s)
Read and parse an APE tag.
Definition: apetag.c:118
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:639
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:449
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:260
#define FFMIN(a, b)
Definition: common.h:96
#define AVFMT_EVENT_FLAG_METADATA_UPDATED
The call resulted in updated metadata.
Definition: avformat.h:1674
#define s(width, name)
Definition: cbs_vp9.c:257
static void error(const char *err)
Stream structure.
Definition: avformat.h:881
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:40
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
void * buf
Definition: avisynth_c.h:766
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
static int handle_id3(AVFormatContext *s, AVPacket *pkt)
Definition: aacdec.c:122
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:456
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
int raw_codec_id
Raw demuxers store their codec ID here.
Definition: avformat.h:700
static struct @306 state
Main libavformat public API header.
int ff_id3v2_match(const uint8_t *buf, const char *magic)
Detect ID3v2 Header.
Definition: id3v2.c:143
int ffio_init_context(AVIOContext *s, unsigned char *buffer, int buffer_size, int write_flag, void *opaque, int(*read_packet)(void *opaque, uint8_t *buf, int buf_size), int(*write_packet)(void *opaque, uint8_t *buf, int buf_size), int64_t(*seek)(void *opaque, int64_t offset, int whence))
Definition: aviobuf.c:81
void ff_id3v2_read_dict(AVIOContext *pb, AVDictionary **metadata, const char *magic, ID3v2ExtraMeta **extra_meta)
Read an ID3v2 tag into specified dictionary and retrieve supported extra metadata.
Definition: id3v2.c:1115
int ff_id3v2_tag_len(const uint8_t *buf)
Get the length of an ID3v2 tag.
Definition: id3v2.c:156
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
#define AV_DICT_IGNORE_SUFFIX
Return first entry in a dictionary whose first part corresponds to the search key, ignoring the suffix of the found key string.
Definition: dict.h:70
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:358
static int64_t fsize(FILE *f)
Definition: audiomatch.c:28
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
This structure stores compressed data.
Definition: avcodec.h:1454