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Audio output

Register name used to load filter: aout
This filter may be automatically loaded during graph resolution.

This filter writes a single PCM (uncompressed) audio input PID to a sound card or other audio output device.

The longer the audio buffering bdur is, the longer the audio latency will be (pause/resume). The quality of fast forward audio playback will also be degraded when using large audio buffers.

If clock is set, the filter will report system time (in us) and corresponding packet CTS for other filters to use for AV sync.


drv (cstr): audio driver name
bnum (uint, default: 2): number of audio buffers (0 for auto)
bdur (uint, default: 100): total duration of all buffers in ms (0 for auto)
threaded (bool, default: true): force dedicated thread creation if sound card driver is not threaded
dur (frac, default: 0): only play the specified duration
clock (bool, default: true): hint audio clock for this stream
speed (dbl, default: 1.0, updatable): set playback speed. If speed is negative and start is 0, start is set to -1
start (dbl, default: 0.0, updatable): set playback start offset. A negative value means percent of media duration with -1 equal to duration
vol (uint, default: 100, minmax: 0-100, updatable): set default audio volume, as a percentage between 0 and 100
pan (uint, default: 50, minmax: 0-100, updatable): set stereo pan, as a percentage between 0 and 100, 50 being centered
buffer (uint, default: 200): set playout buffer in ms
mbuffer (uint, default: 0): set max buffer occupancy in ms. If less than buffer, use buffer
rbuffer (uint, default: 0, updatable): rebuffer trigger in ms. If 0 or more than buffer, disable rebuffering
adelay (frac, default: 0, updatable): set audio delay in sec
buffer_done (bool): buffer done indication (readonly, for user app)
rebuffer (luint): system time in us at which last rebuffer started, 0 if not rebuffering (readonly, for user app)
media_offset (dbl, default: 0): media offset (substract this value to CTS to get media time - readonly)