ofxVideoRecorder output problem(ofx Big Sur issue?)

I cloned ofxVideoRecorder repository from github and opened example app with xcode, with no code edditing, build and run the example and tried to record some video(type r then c),then the video file have been generated but the file has only 158 byte and can’t be playback.

it seems no error while building and running app so i have no idea wheather this is because of my environment problem or something.
i suspect osx big sur related problem because i used with no problem about a year ago.

any info/advice woud be appreciated, thanks!

donno why, but (maybe) updating ffmpeg and rebuild the app would have solved the problem :wink:

osx 11.3.1 (Big Sur)
ffmpeg version 4.4
openframeworks 0.11.2

Not sure if related but when trying OSX and h264 recording I needed to add pixel format to the ffmpeg command else output would be blank: -pix_fmt yuv420p (scroll to bottom)