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afc.c
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1 /*
2  * AFC demuxer
3  * Copyright (c) 2012 Paul B Mahol
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
23 #include "avformat.h"
24 #include "internal.h"
25 
26 typedef struct AFCDemuxContext {
27  int64_t data_end;
29 
31 {
33  AVStream *st;
34 
35  st = avformat_new_stream(s, NULL);
36  if (!st)
37  return AVERROR(ENOMEM);
40  st->codec->channels = 2;
42 
43  if (ff_alloc_extradata(st->codec, 1))
44  return AVERROR(ENOMEM);
45  st->codec->extradata[0] = 8 * st->codec->channels;
46 
47  c->data_end = avio_rb32(s->pb) + 32LL;
48  st->duration = avio_rb32(s->pb);
49  st->codec->sample_rate = avio_rb16(s->pb);
50  avio_skip(s->pb, 22);
51  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
52 
53  return 0;
54 }
55 
57 {
59  int64_t size;
60  int ret;
61 
62  size = FFMIN(c->data_end - avio_tell(s->pb), 18 * 128);
63  if (size <= 0)
64  return AVERROR_EOF;
65 
66  ret = av_get_packet(s->pb, pkt, size);
67  pkt->stream_index = 0;
68  return ret;
69 }
70 
72  .name = "afc",
73  .long_name = NULL_IF_CONFIG_SMALL("AFC"),
74  .priv_data_size = sizeof(AFCDemuxContext),
77  .extensions = "afc",
79 };
#define NULL
Definition: coverity.c:32
#define AVFMT_NOBINSEARCH
Format does not allow to fall back on binary search via read_timestamp.
Definition: avformat.h:491
const char * s
Definition: avisynth_c.h:631
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:4149
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:282
static AVPacket pkt
#define AV_CH_LAYOUT_STEREO
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:683
Format I/O context.
Definition: avformat.h:1314
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:698
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1647
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3805
static int afc_read_header(AVFormatContext *s)
Definition: afc.c:30
#define AVERROR_EOF
End of file.
Definition: error.h:55
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:252
ptrdiff_t size
Definition: opengl_enc.c:101
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:442
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:2338
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:896
audio channel layout utility functions
#define FFMIN(a, b)
Definition: common.h:96
int64_t data_end
Definition: afc.c:27
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:638
Stream structure.
Definition: avformat.h:877
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
enum AVMediaType codec_type
Definition: avcodec.h:1540
enum AVCodecID codec_id
Definition: avcodec.h:1549
int sample_rate
samples per second
Definition: avcodec.h:2287
AVIOContext * pb
I/O context.
Definition: avformat.h:1356
static int afc_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: afc.c:56
#define AVFMT_NOGENSEARCH
Format does not allow to fall back on generic search.
Definition: avformat.h:492
int ff_alloc_extradata(AVCodecContext *avctx, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:2979
static int flags
Definition: cpu.c:47
AVInputFormat ff_afc_demuxer
Definition: afc.c:71
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:936
Main libavformat public API header.
static double c[64]
#define AVFMT_NO_BYTE_SEEK
Format does not allow seeking by bytes.
Definition: avformat.h:493
int channels
number of audio channels
Definition: avcodec.h:2288
void * priv_data
Format private data.
Definition: avformat.h:1342
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
int stream_index
Definition: avcodec.h:1469
This structure stores compressed data.
Definition: avcodec.h:1444