Libav
Functions

libavdevice/alsa-audio-common.c File Reference

ALSA input and output: common code. More...

#include <alsa/asoundlib.h>
#include "libavformat/avformat.h"
#include "alsa-audio.h"

Go to the source code of this file.

Functions

static av_cold snd_pcm_format_t codec_id_to_pcm_format (int codec_id)
av_cold int ff_alsa_open (AVFormatContext *ctx, snd_pcm_stream_t mode, unsigned int *sample_rate, int channels, enum CodecID *codec_id)
 Opens an ALSA PCM.
av_cold int ff_alsa_close (AVFormatContext *s1)
 Closes the ALSA PCM.
int ff_alsa_xrun_recover (AVFormatContext *s1, int err)
 Tries to recover from ALSA buffer underrun.

Detailed Description

ALSA input and output: common code.

Author:
Luca Abeni ( lucabe72 email it )
Benoit Fouet ( benoit fouet free fr )
Nicolas George ( nicolas george normalesup org )

Definition in file alsa-audio-common.c.


Function Documentation

static av_cold snd_pcm_format_t codec_id_to_pcm_format ( int  codec_id) [static]

Definition at line 36 of file alsa-audio-common.c.

Referenced by ff_alsa_open().

av_cold int ff_alsa_close ( AVFormatContext s1)

Closes the ALSA PCM.

Parameters:
s1media file handle
Returns:
0

Definition at line 161 of file alsa-audio-common.c.

av_cold int ff_alsa_open ( AVFormatContext s,
snd_pcm_stream_t  mode,
unsigned int *  sample_rate,
int  channels,
enum CodecID codec_id 
)

Opens an ALSA PCM.

Parameters:
smedia file handle
modeeither SND_PCM_STREAM_CAPTURE or SND_PCM_STREAM_PLAYBACK
sample_ratein: requested sample rate; out: actually selected sample rate
channelsnumber of channels
codec_idin: requested CodecID or CODEC_ID_NONE; out: actually selected CodecID, changed only if CODEC_ID_NONE was requested
Returns:
0 if OK, AVERROR_xxx on error

Definition at line 46 of file alsa-audio-common.c.

Referenced by audio_read_header(), and audio_write_header().

int ff_alsa_xrun_recover ( AVFormatContext s1,
int  err 
)

Tries to recover from ALSA buffer underrun.

Parameters:
s1media file handle
errerror code reported by the previous ALSA call
Returns:
0 if OK, AVERROR_xxx on error

Definition at line 169 of file alsa-audio-common.c.

Referenced by audio_read_packet(), and audio_write_packet().