This is a placeholder for me comprehending how video encoding works… I’ll update/edit as I become more familiar.. please don’t assume I have any idea what im talking about.
But, basically you have a GOP (group of pictures) and that GOP has a specified number of frames per second. So lets say you have a 30 FPS video, it has 30 frames per second of data, you can have a number of GOP that is different than that though.
So lets say you have a GOP size of 90, but your frame rate is 30 FPS. You will then have 29 P-Frames per I-Frame, For a total of 87 P-frames and 3 I-Frames.
I-Frames are ENTIRE picture, P-Frames are the “guess” at what changed since the last I-Frame. More I-Frames = more bandwidth.
https://en.wikipedia.org/wiki/Video_compression_picture_types