Aphasemeter

Audio Multiple outputs Transform

Convert input audio to phase meter video output.

FFmpeg filter: aphasemeter — the official reference.

Add it to a graph. The explicit form works for every filter — bind it to its input and read the result from outputs():

$outputs = $audio->addFilter(new Aphasemeter(…))->outputs(); // one stream per output pad

Shorthand. Not available — apply() returns a single stream, and Aphasemeter has multiple outputs. Use addFilter() + outputs() above.

When to use it

TODO — when this filter shines: what it’s the right tool for, what to reach for instead when it isn’t, and how it composes with neighbouring filters.

How to use it

TODO — prose: how the filter actually works and what its key parameters mean (the explanation FFmpeg’s terse option help omits).

Examples

TODO — runnable PHP, with the equivalent ffmpeg CLI alongside.

Gotchas

TODO

See also

TODO

Parameters

Parameter	Type	Default	Range / values	Description
rate	string	25	—	set video rate
size	string	800x400	—	set video size
rc	int	2	0–255	set red contrast
gc	int	7	0–255	set green contrast
bc	int	1	0–255	set blue contrast
mpc	string	none	—	set median phase color
video	bool	true	—	set video output
phasing	bool	false	—	set mono and out-of-phase detection output
tolerance	float	0	0–1	set phase tolerance for mono detection
angle	float	170	90–180	set angle threshold for out-of-phase detection
duration	int	2000000	≥ 0	set minimum mono or out-of-phase duration in seconds

FFmpeg also names these options (use the parameter shown above): r → rate, s → size, t → tolerance, a → angle, d → duration.

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Maps to FFmpeg’s aphasemeter filter. Verified against ffmpeg n7.1.1.