FFmpeg
sndio.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 "avdevice.h"
26 
27 #include "libavdevice/sndio.h"
28 
29 static inline void movecb(void *addr, int delta)
30 {
31  SndioData *s = addr;
32 
33  s->hwpos += delta * s->channels * s->bps;
34 }
35 
37  const char *audio_device)
38 {
39  SndioData *s = s1->priv_data;
40  struct sio_hdl *hdl;
41  struct sio_par par;
42 
43  hdl = sio_open(audio_device, is_output ? SIO_PLAY : SIO_REC, 0);
44  if (!hdl) {
45  av_log(s1, AV_LOG_ERROR, "Could not open sndio device\n");
46  return AVERROR(EIO);
47  }
48 
49  sio_initpar(&par);
50 
51  par.bits = 16;
52  par.sig = 1;
53  par.le = SIO_LE_NATIVE;
54 
55  if (is_output)
56  par.pchan = s->channels;
57  else
58  par.rchan = s->channels;
59  par.rate = s->sample_rate;
60 
61  if (!sio_setpar(hdl, &par) || !sio_getpar(hdl, &par)) {
62  av_log(s1, AV_LOG_ERROR, "Impossible to set sndio parameters, "
63  "channels: %d sample rate: %d\n", s->channels, s->sample_rate);
64  goto fail;
65  }
66 
67  if (par.bits != 16 || par.sig != 1 ||
68  (is_output && (par.pchan != s->channels)) ||
69  (!is_output && (par.rchan != s->channels)) ||
70  (par.rate != s->sample_rate)) {
71  av_log(s1, AV_LOG_ERROR, "Could not set appropriate sndio parameters, "
72  "channels: %d sample rate: %d\n", s->channels, s->sample_rate);
73  goto fail;
74  }
75 
76  s->buffer_size = par.round * par.bps *
77  (is_output ? par.pchan : par.rchan);
78 
79  if (is_output) {
80  s->buffer = av_malloc(s->buffer_size);
81  if (!s->buffer) {
82  av_log(s1, AV_LOG_ERROR, "Could not allocate buffer\n");
83  goto fail;
84  }
85  }
86 
88  s->channels = is_output ? par.pchan : par.rchan;
89  s->sample_rate = par.rate;
90  s->bps = par.bps;
91 
92  sio_onmove(hdl, movecb, s);
93 
94  if (!sio_start(hdl)) {
95  av_log(s1, AV_LOG_ERROR, "Could not start sndio\n");
96  goto fail;
97  }
98 
99  s->hdl = hdl;
100 
101  return 0;
102 
103 fail:
104  av_freep(&s->buffer);
105 
106  if (hdl)
107  sio_close(hdl);
108 
109  return AVERROR(EIO);
110 }
111 
113 {
114  av_freep(&s->buffer);
115 
116  if (s->hdl)
117  sio_close(s->hdl);
118 
119  return 0;
120 }
int channels
Definition: sndio.h:41
Format I/O context.
Definition: avformat.h:1358
enum AVCodecID codec_id
Definition: sndio.h:34
#define av_cold
Definition: attributes.h:82
#define av_malloc(s)
float delta
int sample_rate
Definition: sndio.h:42
#define av_log(a,...)
Main libavdevice API header.
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
uint8_t * buffer
Definition: sndio.h:37
#define fail()
Definition: checkasm.h:121
int bps
Definition: sndio.h:38
#define s(width, name)
Definition: cbs_vp9.c:257
int ff_sndio_close(SndioData *s)
Definition: sndio.c:112
static void movecb(void *addr, int delta)
Definition: sndio.c:29
int buffer_size
Definition: sndio.h:39
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
struct sio_hdl * hdl
Definition: sndio.h:33
void * priv_data
Format private data.
Definition: avformat.h:1386
#define av_freep(p)
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions