A wishlist for audio

[AlanD]

There are a few things I am always wishing I could just do inside AVIdemux instead of having to resort to Audacity. Programs like Audacity have a million useful options for some seriously heavy duty sound processing, but there are just one or two features that get used all the time.

COMPRESSOR / NON-LINEAR GAIN

AVIdemux is great if I just want to boost the audio gain, but there are videos where most of it is too quiet, but a short section in the middle is already too close to the top of the range. If I try to use auto-gain, it will have no effect. If I use a manual gain of, say, 6db, most of the sound will be great, but there will be clipping on the loud section in the middle. This is commonly fixed using a compressor function in Audacity etc. Audio compression should not be confused with the filesize compression of MP3 etc. Its not unlike using the gamma-correction in an image where you push up the mid-range values. It would be great if AVIdemux contained a basic compressor, to cut out the need to do the Audacity file shuffle. On the AVIdemux gain control, as well as having the amount of gain, you could also have a 0-100 value for amount of compression. A default value of zero would be the current linear amplification. Greater than zero would represent the degree of compression.

FADE IN AND OUT

On pieces of video where I want to fade the screen in and out at the start and end, it would be great to be able to fade the audio in and out in parallel. My ideal would be to have an option on the Fade To Black filter, a tick box to say "Link audio levels" or something like that, though I realise that might not be possible with the AVIdemux architecture. Even where the video isn't faded in and out, there are still times when it is good to put just a one-second fade-in fade-out on the video, because it cuts out a harsh assault on the ear if your video is very noisy from frame 1.

ARE STEREO CHANNELS PROCESSED SEPARATELY?

If I've shot a video of, say, an interview, with an external microphone, it is quite possible that the microphone had to be positioned to one side of the video centre. If it is on the left, it can mean that the peak of the left channel is a bit louder than the peaks on the right. With packages such as Audacity, you can auto-adjust the gains of the two channels independently as a way of re-centering the sound. Does AVIdemux process the channels independently? If not, it would be great to see it as an option on the autogain dialog.

[eumagga0x2a]

Does AVIdemux process the channels independently?

No, it does not.

I second every single wish and suggestion here, but don't see any of that (with a tiny bit of doubt about the compressor functionality) happening with current resources. Code contributions warmly welcome.