Write a gtk$4$ code to use GTK window to display the frames extracted from a video file.

C$,$ ffmpeg $($av library$),$ GTK$4.$

Frame rate should be a command line argument.

Use a pthread for decoding. No assumption on the decoding speed.

Displaying thread can be either a pthread or a GTK timer.

No busy$-$waiting.

Fixed buffer size for thread communication, with circular buffer solution.

Mutual exclusion and thread synchronization between decoding thread and displaying thread should be

correct.

Clean up $-$ Unrelated code should be removed.