ffmpeg

ffmpeg is better than Handbrake at converting audio while leaving video alone. If you want video passthrough, ffmpeg is for you.

Grab zip package from here:

Version: nightly Architecture: 64-bit Linking: Static

Make secondary audio track primary

Example encode mapping to select a single audio track as main (this is mapping track #2 onto track #0):

.\ffmpeg.exe -i "C:\path\to\source.mkv" -map 0:0 -map 0:2 -acodec copy -vcodec copy "C:\path\to\dest.mkv"

Convert DTS to AAC

This is great for converting DTS encoded audio to AAC when you need to play files on a player that doesn't support DTS. (There's actually nothing DTS-specific here. DTS is just an example of something that isn't well supported. E.g., Chromecast.)

.\ffmpeg.exe -i "C:\path\to\source.mkv" -c:v copy -c:a aac "C:\path\to\dest.mkv"

Convert image plus audio to video

For more info, see discussion here.

ffmpeg.exe -r 1 -loop 1 -i image.png -i audio.wav -acodec copy -r 1 -shortest -vf scale=1280:720 output.flv

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