FFmpeg  4.4.4
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 {
32  AFCDemuxContext *c = s->priv_data;
33  AVStream *st;
34  int ret;
35 
36  st = avformat_new_stream(s, NULL);
37  if (!st)
38  return AVERROR(ENOMEM);
41  st->codecpar->channels = 2;
43 
44  if ((ret = ff_alloc_extradata(st->codecpar, 1)) < 0)
45  return ret;
46  st->codecpar->extradata[0] = 8 * st->codecpar->channels;
47 
48  c->data_end = avio_rb32(s->pb) + 32LL;
49  st->duration = avio_rb32(s->pb);
50  st->codecpar->sample_rate = avio_rb16(s->pb);
51  avio_skip(s->pb, 22);
52  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
53 
54  return 0;
55 }
56 
58 {
59  AFCDemuxContext *c = s->priv_data;
60  int64_t size;
61  int ret;
62 
63  size = FFMIN(c->data_end - avio_tell(s->pb), 18 * 128);
64  if (size <= 0)
65  return AVERROR_EOF;
66 
67  ret = av_get_packet(s->pb, pkt, size);
68  pkt->stream_index = 0;
69  return ret;
70 }
71 
73  .name = "afc",
74  .long_name = NULL_IF_CONFIG_SMALL("AFC"),
75  .priv_data_size = sizeof(AFCDemuxContext),
78  .extensions = "afc",
80 };
AVInputFormat ff_afc_demuxer
Definition: afc.c:72
static int afc_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: afc.c:57
static int afc_read_header(AVFormatContext *s)
Definition: afc.c:30
Main libavformat public API header.
#define AVFMT_NO_BYTE_SEEK
Format does not allow seeking by bytes.
Definition: avformat.h:470
#define AVFMT_NOGENSEARCH
Format does not allow to fall back on generic search.
Definition: avformat.h:469
#define AVFMT_NOBINSEARCH
Format does not allow to fall back on binary search via read_timestamp.
Definition: avformat.h:468
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
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:766
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:781
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
#define flags(name, subs,...)
Definition: cbs_av1.c:561
#define s(width, name)
Definition: cbs_vp9.c:257
audio channel layout utility functions
#define FFMIN(a, b)
Definition: common.h:105
#define NULL
Definition: coverity.c:32
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:545
#define AV_CH_LAYOUT_STEREO
@ AV_CODEC_ID_ADPCM_AFC
Definition: codec_id.h:385
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4509
#define AVERROR_EOF
End of file.
Definition: error.h:55
#define AVERROR(e)
Definition: error.h:43
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
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:4945
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:3314
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
int64_t data_end
Definition: afc.c:27
uint64_t channel_layout
Audio only.
Definition: codec_par.h:162
int channels
Audio only.
Definition: codec_par.h:166
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int sample_rate
Audio only.
Definition: codec_par.h:170
Format I/O context.
Definition: avformat.h:1232
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
This structure stores compressed data.
Definition: packet.h:346
int stream_index
Definition: packet.h:371
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:922
AVPacket * pkt
Definition: movenc.c:59
int size
static double c[64]