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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/intreadwrite.h"
24 #include "avformat.h"
25 #include "avio_internal.h"
26 #include "internal.h"
27 #include "id3v1.h"
28 #include "id3v2.h"
29 #include "apetag.h"
30 
31 #define ADTS_HEADER_SIZE 7
32 
34 {
35  int max_frames = 0, first_frames = 0;
36  int fsize, frames;
37  const uint8_t *buf0 = p->buf;
38  const uint8_t *buf2;
39  const uint8_t *buf;
40  const uint8_t *end = buf0 + p->buf_size - 7;
41 
42  buf = buf0;
43 
44  for (; buf < end; buf = buf2 + 1) {
45  buf2 = buf;
46 
47  for (frames = 0; buf2 < end; frames++) {
48  uint32_t header = AV_RB16(buf2);
49  if ((header & 0xFFF6) != 0xFFF0) {
50  if (buf != buf0) {
51  // Found something that isn't an ADTS header, starting
52  // from a position other than the start of the buffer.
53  // Discard the count we've accumulated so far since it
54  // probably was a false positive.
55  frames = 0;
56  }
57  break;
58  }
59  fsize = (AV_RB32(buf2 + 3) >> 13) & 0x1FFF;
60  if (fsize < 7)
61  break;
62  fsize = FFMIN(fsize, end - buf2);
63  buf2 += fsize;
64  }
65  max_frames = FFMAX(max_frames, frames);
66  if (buf == buf0)
67  first_frames = frames;
68  }
69 
70  if (first_frames >= 3)
71  return AVPROBE_SCORE_EXTENSION + 1;
72  else if (max_frames > 100)
74  else if (max_frames >= 3)
75  return AVPROBE_SCORE_EXTENSION / 2;
76  else if (first_frames >= 1)
77  return 1;
78  else
79  return 0;
80 }
81 
83 {
84  AVStream *st;
85  uint16_t state;
86 
87  st = avformat_new_stream(s, NULL);
88  if (!st)
89  return AVERROR(ENOMEM);
90 
94 
95  ff_id3v1_read(s);
96  if ((s->pb->seekable & AVIO_SEEKABLE_NORMAL) &&
98  int64_t cur = avio_tell(s->pb);
100  avio_seek(s->pb, cur, SEEK_SET);
101  }
102 
103  // skip data until the first ADTS frame is found
104  state = avio_r8(s->pb);
105  while (!avio_feof(s->pb) && avio_tell(s->pb) < s->probesize) {
106  state = (state << 8) | avio_r8(s->pb);
107  if ((state >> 4) != 0xFFF)
108  continue;
109  avio_seek(s->pb, -2, SEEK_CUR);
110  break;
111  }
112  if ((state >> 4) != 0xFFF)
113  return AVERROR_INVALIDDATA;
114 
115  // LCM of all possible ADTS sample rates
116  avpriv_set_pts_info(st, 64, 1, 28224000);
117 
118  return 0;
119 }
120 
122 {
123  AVDictionary *metadata = NULL;
124  AVIOContext ioctx;
125  ID3v2ExtraMeta *id3v2_extra_meta = NULL;
126  int ret;
127 
128  ret = av_append_packet(s->pb, pkt, ff_id3v2_tag_len(pkt->data) - pkt->size);
129  if (ret < 0) {
130  av_packet_unref(pkt);
131  return ret;
132  }
133 
134  ffio_init_context(&ioctx, pkt->data, pkt->size, 0, NULL, NULL, NULL, NULL);
135  ff_id3v2_read_dict(&ioctx, &metadata, ID3v2_DEFAULT_MAGIC, &id3v2_extra_meta);
136  if ((ret = ff_id3v2_parse_priv_dict(&metadata, &id3v2_extra_meta)) < 0)
137  goto error;
138 
139  if (metadata) {
140  if ((ret = av_dict_copy(&s->metadata, metadata, 0)) < 0)
141  goto error;
143  }
144 
145 error:
146  av_packet_unref(pkt);
147  ff_id3v2_free_extra_meta(&id3v2_extra_meta);
148  av_dict_free(&metadata);
149 
150  return ret;
151 }
152 
154 {
155  int ret, fsize;
156 
157  // Parse all the ID3 headers between frames
158  while (1) {
161  if ((ret = handle_id3(s, pkt)) >= 0) {
162  continue;
163  }
164  }
165  break;
166  }
167 
168  if (ret < 0)
169  return ret;
170 
171  if (ret < ADTS_HEADER_SIZE) {
172  av_packet_unref(pkt);
173  return AVERROR(EIO);
174  }
175 
176  if ((AV_RB16(pkt->data) >> 4) != 0xfff) {
177  av_packet_unref(pkt);
178  return AVERROR_INVALIDDATA;
179  }
180 
181  fsize = (AV_RB32(pkt->data + 3) >> 13) & 0x1FFF;
182  if (fsize < ADTS_HEADER_SIZE) {
183  av_packet_unref(pkt);
184  return AVERROR_INVALIDDATA;
185  }
186 
187  ret = av_append_packet(s->pb, pkt, fsize - pkt->size);
188  if (ret < 0)
189  av_packet_unref(pkt);
190 
191  return ret;
192 }
193 
195  .name = "aac",
196  .long_name = NULL_IF_CONFIG_SMALL("raw ADTS AAC (Advanced Audio Coding)"),
197  .read_probe = adts_aac_probe,
198  .read_header = adts_aac_read_header,
199  .read_packet = adts_aac_read_packet,
200  .flags = AVFMT_GENERIC_INDEX,
201  .extensions = "aac",
202  .mime_type = "audio/aac,audio/aacp,audio/x-aac",
203  .raw_codec_id = AV_CODEC_ID_AAC,
204 };
int64_t probesize
Maximum size of the data read from input for determining the input container format.
Definition: avformat.h:1517
#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:4849
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3885
void ff_id3v1_read(AVFormatContext *s)
Read an ID3v1 tag.
Definition: id3v1.c:235
int size
Definition: avcodec.h:1432
#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:1666
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
static int adts_aac_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: aacdec.c:153
Format I/O context.
Definition: avformat.h:1351
#define ID3v2_HEADER_SIZE
Definition: id3v2.h:30
uint8_t
static int adts_aac_read_header(AVFormatContext *s)
Definition: aacdec.c:82
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
enum AVStreamParseType need_parsing
Definition: avformat.h:1092
int ff_id3v2_parse_priv_dict(AVDictionary **metadata, ID3v2ExtraMeta **extra_meta)
Parse PRIV tags into a dictionary.
Definition: id3v2.c:1231
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4456
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
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:1431
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:797
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:31
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1591
#define AVERROR(e)
Definition: error.h:43
AVInputFormat ff_aac_demuxer
Definition: aacdec.c:194
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
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:3881
void ff_id3v2_free_extra_meta(ID3v2ExtraMeta **extra_meta)
Free memory allocated parsing special (non-text) metadata.
Definition: id3v2.c:1124
#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:451
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
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:1667
#define s(width, name)
Definition: cbs_vp9.c:257
int frames
Definition: movenc.c:65
static void error(const char *err)
Stream structure.
Definition: avformat.h:874
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:40
AVIOContext * pb
I/O context.
Definition: avformat.h:1393
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:592
void * buf
Definition: avisynth_c.h:690
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:470
static int handle_id3(AVFormatContext *s, AVPacket *pkt)
Definition: aacdec.c:121
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:458
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
int raw_codec_id
Raw demuxers store their codec ID here.
Definition: avformat.h:693
static struct @282 state
static int adts_aac_probe(AVProbeData *p)
Definition: aacdec.c:33
Main libavformat public API header.
int ff_id3v2_match(const uint8_t *buf, const char *magic)
Detect ID3v2 Header.
Definition: id3v2.c:142
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
struct AVInputFormat * iformat
The input container format.
Definition: avformat.h:1363
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:1112
int ff_id3v2_tag_len(const uint8_t *buf)
Get the length of an ID3v2 tag.
Definition: id3v2.c:155
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
#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:1021
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:358
static int64_t fsize(FILE *f)
Definition: audiomatch.c:28
This structure stores compressed data.
Definition: avcodec.h:1408