This is basically what I'd like to see. The MPEG-2 files that Instant Replay uses are fine for use within the Instant Replay tool, but once the files are exported, at least in the workflows at my company, they need to be transcoded to another format 100% of the time. If the Export button could be told to use a custom ffmpeg command to trim, transcode, and save the file all in one go, rather than us having to add multiple steps along the way. See below for a mock-up I made (I know it looks like garbage; I'm not a UI dev).