How to fix TV playback issues
Some media players embedded in TV devices have limited features when playing back movie files. This How To helps to fix some issues.
Fixing video orientation issue using null filter
Some TV devices ignore the rotate=90 metadata assigned to the video stream. In general, this occurs when the movie file has been recorded in portrait mode using a smartphone. Therefore, on the TV, the video stream is displayed in landscape mode instead of portrait mode.
The null filter can convert, for example, a 1920x1080 (16/9, rotate=90) video stream to a 1080x1920 (9/16, rotate=0) video stream :
ffmpeg -i "INPUT.mp4" -vf null -c:a copy "OUTPUT.mp4"
Adding a dummy audio stream using anullsrc audio source
Some TV devices cannot display video streams correctly when there is no audio stream. The command below shows how to add a dummy audio stream :
ffmpeg -i "INPUT.mp4" -f lavfi -i anullsrc -c:v copy -shortest "OUTPUT.mp4"