I've been actively trying to figure out how to deal with this situation every night this past week. FFMPEG, various Mp4 repair tools, and so far nothing has been able to fix at least 6 files that I have (1+GB).
My corrupt files are NOT from turning the drone, extender or app off too soon -- I ALWAYS press the stop record button first, and then wait until the led on the camera is green (as opposed to red or flashing)
I do know for a FACT that I have had a couple files that were corrupt that DID get fixed by rebooting the drone -- but some just simply are not fixed this way.
Sometimes, I have perfect files with no corruption. Sometimes, 1st flight is effed, 2nd is fine.. sometimes, both are bad, sometimes, all are good.. no pattern. I have over 50 files from flights this past week, and 6 of them are bad files.
I have had these failures on both the stock 4gb SDcard and a new 32gb -- both sandisk UC (I don't recall the speed etc)
I went ahead and ordered a sandisk ultra the other day and it should be here today.. it's the only thing I can think of that is the problem. (and yes, I've tried formatting the card while in the drone, and still the problem unpredictably persists)
This is all reminiscent of issues I had with the AR.Drone 2.0 -- I've had many many files that the drone could not repair on it's own, nor could I repair with utilities, either. (but yes some were successfully repaired)