Extract audio and resample example

3d0c / gmf

Go Media Framework

MIT License

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Extract audio and resample example #123

Open expd opened 4 years ago

expd commented 4 years ago

Hi,

Can you provide an example of how to use the resampler to downsample an audio stream and get access to the raw pcm audio data?

3d0c commented 4 years ago

Hi, @expd. It's pretty easy, I'll writre it ASPA. The main thing is pretty the same you can find in trancode.go:

Open input context
Select AUDIO streams
Open output codecs (e.g. pcm_s16le)
Initialize Swr context
Do converrtion
Write output

Just wait a bit, and I'll write it.

expd commented 4 years ago

I think some of the conversion functionality is missing ffmpeg docs show that there's a different calculation for the number of samples required. I'm trying to convert 48/stereo to 16/mono.