ffmpeg asyncts usage

Question

How can I use the new asyncts in ffmpeg (or avconv)? Which is the right syntax?

ffmpeg -i 1.mp4 -i 2.wav -vcodec copy -strict experimental -acodec libmp3lame -ab 128k -f flv -map 0:0 -map 1:0 -filter_complex "asyncts=max_comp" 3.mp4

Generates:

[asyncts filter @ 0x2a58640] Missing key or no key/value separator found after key 'max_comp' [asyncts @ 0x2952380] Error parsing options string 'max_comp'. Error initializing filter 'asyncts' with args 'max_comp'

Answer 1

From the docs, it appears that max_comp takes an argument:

‘max_comp’
Maximum compensation in samples per second.

So you should set it as you would any other filter argument:

ffmpeg -i 1.mp4 -i 2.wav ... -filter_complex "asyncts=max_comp=44100" 3.mp4

^{(Of course I don't what's actually an appropriate value for your situation.)}