I have a problem. I have recorded my videos separately, and then added sound to it. Sometimes, sound is longer or less in duration compared to video duration. Usually sound is longer, sometimes around 20 seconds. To me, when running on my PC through flv or some Windows Media player, that is not problem, since after video is over, last capture of video stays displayed (like an image), and sounds is still executing, and video ends after sound is over. So everything is ok at my PC when running it like .flv or .mp4 file. But, when I upload that on Google drive or some other place on web (that is, when I run it in my browser for viewing after upload), I see my video is cutted to the lenght of the video duration (so my sound is cutted). I understand that this is because of different duration sizes of sound and video.
Now I need a command with ffmpeg that can make my video to be extened to my sound duration. I would like not to reencode my videos with sound again (in sense that I would need to put my mp3 file in ffmpeg command) if I don't need (since I have many videos and sound is already inserted in them), but just to re-encode video with some ffmpeg command to extend video lenght to sound lenght.
I have watched this (not sure at the momen if this would even help me): https://superuser.com/questions/801547/ffmpeg-add-audio-but-keep-video-length-the-same-not-shortest
But with this approach, you have to reencode video with sound (mp3 or similar) file first.
Can it be done, and what would be command, or commands for it? (And if only way is to re-encode it with mp3 file, what would be command for it?)
Edit: I don't want to cut my sound, I need to hold last frame till my sound is over. Currently last frame is holded only when viewing on my PC, when I upload that, clip is cutted immediately when video stops.