Can you include the full ffmpeg command? What version of ffmpeg? Is the green when outputting jpegs or streaming mp4?
If you are playing the mp4 content and the screen is partially green, just accept it because it is an overpriced cam that does the same thing to me most of the time. I hate to publicly bash that brand, but my super cheap generic chinese $20 ip cams perform way better than the $50 reolink that I got from amazn.
If it is a jpeg issue, then you probably need to pass the jpeg buffer through pipe2jpeg to collect all the pieces befores outputting a complete jpeg.
