FFmpeg  2.1.1
adp.c
Go to the documentation of this file.
1 /*
2  * ADP demuxer
3  * Copyright (c) 2013 James Almer
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 
22 #include "libavutil/channel_layout.h"
23 #include "libavutil/intreadwrite.h"
24 #include "avformat.h"
25 #include "internal.h"
26 
27 static int adp_probe(AVProbeData *p)
28 {
29  int i;
30 
31  if (p->buf_size < 32)
32  return 0;
33 
34  for (i = 0; i < p->buf_size - 3; i+=32)
35  if (p->buf[i] != p->buf[i+2] || p->buf[i+1] != p->buf[i+3])
36  return 0;
37 
38  return p->buf_size < 260 ? 1 : AVPROBE_SCORE_MAX / 4;
39 }
40 
42 {
43  AVStream *st;
44 
45  st = avformat_new_stream(s, NULL);
46  if (!st)
47  return AVERROR(ENOMEM);
48 
52  st->codec->channels = 2;
53  st->codec->sample_rate = 48000;
54  st->start_time = 0;
55  if (s->pb->seekable)
57 
58  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
59 
60  return 0;
61 }
62 
64 {
65  int ret, size = 1024;
66 
67  if (url_feof(s->pb))
68  return AVERROR_EOF;
69 
70  ret = av_get_packet(s->pb, pkt, size);
71 
72  if (ret != size) {
73  if (ret < 0) {
74  av_free_packet(pkt);
75  return ret;
76  }
77  av_shrink_packet(pkt, ret);
78  }
79  pkt->stream_index = 0;
80 
81  return ret;
82 }
83 
85  .name = "adp",
86  .long_name = NULL_IF_CONFIG_SMALL("ADP"),
87  .read_probe = adp_probe,
88  .read_header = adp_read_header,
89  .read_packet = adp_read_packet,
90  .extensions = "adp,dtk",
91 };
static int adp_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: adp.c:63
const char * s
Definition: avisynth_c.h:668
int size
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:279
AVInputFormat ff_adp_demuxer
Definition: adp.c:84
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:478
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: avpacket.c:103
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:3922
static int adp_read_header(AVFormatContext *s)
Definition: adp.c:41
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:261
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:686
#define AV_CH_LAYOUT_STEREO
Format I/O context.
Definition: avformat.h:968
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:336
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3348
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:200
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:151
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:1934
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:337
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:117
ret
Definition: avfilter.c:961
static int adp_probe(AVProbeData *p)
Definition: adp.c:27
Stream structure.
Definition: avformat.h:667
enum AVMediaType codec_type
Definition: avcodec.h:1154
enum AVCodecID codec_id
Definition: avcodec.h:1157
int sample_rate
samples per second
Definition: avcodec.h:1873
AVIOContext * pb
I/O context.
Definition: avformat.h:1001
This structure contains the data a format has to probe a file.
Definition: avformat.h:334
int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
Return audio frame duration.
Definition: utils.c:2946
#define AVERROR_EOF
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:342
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:720
int url_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:280
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:713
Main libavformat public API header.
int channels
number of audio channels
Definition: avcodec.h:1874
#define AVERROR(e)
static AVPacket pkt
Definition: demuxing.c:52
int stream_index
Definition: avcodec.h:1065
This structure stores compressed data.
Definition: avcodec.h:1040