FFmpeg  4.0
sndio_dec.c
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1 /*
2  * sndio play and grab interface
3  * Copyright (c) 2010 Jacob Meuser
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 <stdint.h>
23 #include <sndio.h>
24 
25 #include "libavutil/internal.h"
26 #include "libavutil/opt.h"
27 #include "libavutil/time.h"
28 
29 #include "libavformat/avformat.h"
30 #include "libavformat/internal.h"
31 
32 #include "libavdevice/sndio.h"
33 
35 {
36  SndioData *s = s1->priv_data;
37  AVStream *st;
38  int ret;
39 
40  st = avformat_new_stream(s1, NULL);
41  if (!st)
42  return AVERROR(ENOMEM);
43 
44  ret = ff_sndio_open(s1, 0, s1->url);
45  if (ret < 0)
46  return ret;
47 
48  /* take real parameters */
50  st->codecpar->codec_id = s->codec_id;
52  st->codecpar->channels = s->channels;
53 
54  avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
55 
56  return 0;
57 }
58 
60 {
61  SndioData *s = s1->priv_data;
62  int64_t bdelay, cur_time;
63  int ret;
64 
65  if ((ret = av_new_packet(pkt, s->buffer_size)) < 0)
66  return ret;
67 
68  ret = sio_read(s->hdl, pkt->data, pkt->size);
69  if (ret == 0 || sio_eof(s->hdl)) {
70  av_packet_unref(pkt);
71  return AVERROR_EOF;
72  }
73 
74  pkt->size = ret;
75  s->softpos += ret;
76 
77  /* compute pts of the start of the packet */
78  cur_time = av_gettime();
79 
80  bdelay = ret + s->hwpos - s->softpos;
81 
82  /* convert to pts */
83  pkt->pts = cur_time - ((bdelay * 1000000) /
84  (s->bps * s->channels * s->sample_rate));
85 
86  return 0;
87 }
88 
90 {
91  SndioData *s = s1->priv_data;
92 
93  ff_sndio_close(s);
94 
95  return 0;
96 }
97 
98 static const AVOption options[] = {
99  { "sample_rate", "", offsetof(SndioData, sample_rate), AV_OPT_TYPE_INT, {.i64 = 48000}, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
100  { "channels", "", offsetof(SndioData, channels), AV_OPT_TYPE_INT, {.i64 = 2}, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
101  { NULL },
102 };
103 
104 static const AVClass sndio_demuxer_class = {
105  .class_name = "sndio indev",
106  .item_name = av_default_item_name,
107  .option = options,
108  .version = LIBAVUTIL_VERSION_INT,
110 };
111 
113  .name = "sndio",
114  .long_name = NULL_IF_CONFIG_SMALL("sndio audio capture"),
115  .priv_data_size = sizeof(SndioData),
119  .flags = AVFMT_NOFILE,
120  .priv_class = &sndio_demuxer_class,
121 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
AVOption.
Definition: opt.h:246
static const AVOption options[]
Definition: sndio_dec.c:98
int channels
Definition: sndio.h:41
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
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:4811
channels
Definition: aptx.c:30
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
int size
Definition: avcodec.h:1431
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
static int audio_read_packet(AVFormatContext *s1, AVPacket *pkt)
Definition: sndio_dec.c:59
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1342
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
enum AVCodecID codec_id
Definition: sndio.h:34
#define av_cold
Definition: attributes.h:82
AVOptions.
int sample_rate
Definition: sndio.h:42
static const AVClass sndio_demuxer_class
Definition: sndio_dec.c:104
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4441
uint8_t * data
Definition: avcodec.h:1430
static int flags
Definition: log.c:55
#define AVERROR_EOF
End of file.
Definition: error.h:55
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
AVInputFormat ff_sndio_demuxer
Definition: sndio_dec.c:112
#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:186
char * url
input or output URL.
Definition: avformat.h:1438
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
common internal API header
int bps
Definition: sndio.h:38
static av_cold int audio_read_close(AVFormatContext *s1)
Definition: sndio_dec.c:89
int ff_sndio_close(SndioData *s)
Definition: sndio.c:112
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
int64_t av_gettime(void)
Get the current time in microseconds.
Definition: time.c:39
Stream structure.
Definition: avformat.h:873
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
sample_rate
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:592
int buffer_size
Definition: sndio.h:39
Describe the class of an AVClass context structure.
Definition: log.h:67
#define AV_OPT_FLAG_DECODING_PARAM
a generic parameter which can be set by the user for demuxing or decoding
Definition: opt.h:277
av_cold int ff_sndio_open(AVFormatContext *s1, int is_output, const char *audio_device)
Definition: sndio.c:36
#define s1
Definition: regdef.h:38
int64_t hwpos
Definition: sndio.h:35
int64_t softpos
Definition: sndio.h:36
struct sio_hdl * hdl
Definition: sndio.h:33
int sample_rate
Audio only.
Definition: avcodec.h:3994
Main libavformat public API header.
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:465
void * priv_data
Format private data.
Definition: avformat.h:1370
int channels
Audio only.
Definition: avcodec.h:3990
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
static av_cold int audio_read_header(AVFormatContext *s1)
Definition: sndio_dec.c:34
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
This structure stores compressed data.
Definition: avcodec.h:1407
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1423