All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
Functions | Variables
alsa-audio-enc.c File Reference

ALSA input and output: output. More...

#include <alsa/asoundlib.h>
#include "libavutil/time.h"
#include "libavformat/internal.h"
#include "avdevice.h"
#include "alsa-audio.h"

Go to the source code of this file.


static av_cold int audio_write_header (AVFormatContext *s1)
static int audio_write_packet (AVFormatContext *s1, AVPacket *pkt)
static int audio_write_frame (AVFormatContext *s1, int stream_index, AVFrame **frame, unsigned flags)
static void audio_get_output_timestamp (AVFormatContext *s1, int stream, int64_t *dts, int64_t *wall)
static int audio_get_device_list (AVFormatContext *h, AVDeviceInfoList *device_list)


static const AVClass alsa_muxer_class
AVOutputFormat ff_alsa_muxer

Detailed Description

ALSA input and output: output.

Luca Abeni ( lucabe72 email it )
Benoit Fouet ( benoit fouet free fr )

This avdevice encoder allows to play audio to an ALSA (Advanced Linux Sound Architecture) device.

The filename parameter is the name of an ALSA PCM device capable of capture, for example "default" or "plughw:1"; see the ALSA documentation for naming conventions. The empty string is equivalent to "default".

The playback period is set to the lower value available for the device, which gives a low latency suitable for real-time playback.

Definition in file alsa-audio-enc.c.

Function Documentation

static av_cold int audio_write_header ( AVFormatContext s1)

Definition at line 47 of file alsa-audio-enc.c.

static int audio_write_packet ( AVFormatContext s1,
AVPacket pkt 

Definition at line 80 of file alsa-audio-enc.c.

Referenced by audio_write_frame().

static int audio_write_frame ( AVFormatContext s1,
int  stream_index,
AVFrame **  frame,
unsigned  flags 

Definition at line 116 of file alsa-audio-enc.c.

static void audio_get_output_timestamp ( AVFormatContext s1,
int  stream,
int64_t *  dts,
int64_t *  wall 

Definition at line 135 of file alsa-audio-enc.c.

static int audio_get_device_list ( AVFormatContext h,
AVDeviceInfoList device_list 

Definition at line 145 of file alsa-audio-enc.c.

Variable Documentation

const AVClass alsa_muxer_class
Initial value:
= {
.class_name = "ALSA muxer",
.item_name = av_default_item_name,

Definition at line 150 of file alsa-audio-enc.c.

AVOutputFormat ff_alsa_muxer
Initial value:
= {
.name = "alsa",
.long_name = NULL_IF_CONFIG_SMALL("ALSA audio output"),
.priv_data_size = sizeof(AlsaData),
.audio_codec = DEFAULT_CODEC_ID,
.video_codec = AV_CODEC_ID_NONE,
.write_uncoded_frame = audio_write_frame,
.get_output_timestamp = audio_get_output_timestamp,
.priv_class = &alsa_muxer_class,

Definition at line 157 of file alsa-audio-enc.c.