[FFmpeg-user] how to edit metadata in flv file

[qw]

Hi,


I have two questions about ffmpeg usage:


1)
How to edit metadata in flv file by using ffmpeg, such as changing some key's value in flv file's metadata tag?


2)
Normally, there are two streams in flv files, i.e. audio and video streams. I want to keep some part empty of in audio or video stream, which mean there only exist video or audio stream in that part. How to produce that kind of flv file by using ffmpeg?


Thanks!


Regards


Andrew