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I am able to convert it to wav using:

ffmpeg -i audio.3pg audio.wav

but I need the command to convert it to ulaw.


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up vote 2 down vote accepted

The simplest example is:

$ ffmpeg -i input -codec:a pcm_mulaw output.wav

Refer to ffmpeg -encoders to see a list of available encoders.

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thanks, but I would like to have the ulaw extension instead, when I change the extensions I get [NULL @ 0250ef00] Unable to find a suitable output format for 'output.ulaw' output.ulaw: Invalid argument – meda Nov 6 '13 at 22:21
@meda You can probably make a raw, headerless output with: ffmpeg -i input -codec:a pcm_mulaw -f mulaw output.ulaw. The -codec:a pcm_mulaw might be superfluous but it does not hurt to be explicit. I'm not sure if this is what you want. – LordNeckbeard Nov 6 '13 at 23:52
what do you mean, sorry I did not get it – meda Nov 7 '13 at 1:16
@meda If you use .wav as an extension, ffmpeg automatically guesses that you want a WAV container wrapping your PCM audio. If you do not want that, and instead need raw audio data in a .ulaw file, you need to use -f mulaw to force ffmpeg to use the PCM mu-law output format. – slhck Nov 7 '13 at 6:20
Ok that worked, eventhough the quality is terrible, thanks anyway – meda Nov 7 '13 at 14:39

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