Utility conversion functions/tools

[mifi]

I have received several suggestions for different nice-to-have features, not directly related to lossless cutting but it could be nice to have anyways:

YouTube audio to video creation (static image)

A tool for creating a video for uploading to youtube from an audio file and an image (Because youtube requires a video track)

ffmpeg -loop 1 -y -i "image.jpg" -i "file.mp3" -shortest -c:v libx264 -c:a copy "file.mp4"

The same options were used with an m4a (aac audio) file. I think it just needed an image file and the libx264 option.

So, I was wondering if you could make a specific "YouTube audio to video creation" option in the "Format" drop-down list? When selected it could then request that an image or images are chosen to be used to satisfy YouTube's video format requirements.

Convert audio to wav or mp3

Maybe extract all streams but select codec to convert to. See #306

Repair truncated/damaged mp4

An mp4 that has been cut off (e.g. not finished downloading) will not play back because the MOOV atom is often at the end of the file. This might be fixed by incorporating a tool like untrunc.

Quickly transcode til low file size

For example when you need to share a video by email but the video is too large, by using x264 we can encode very low bit rate with acceptable quality, example:

ffmpeg -i input -c:v libx264 -c:a aac -crf 30 "$file"-out.mp4

Other

See also #372