Prettz
3rd September 2006, 04:39
I've got a couple questions about how x264's zones work internally. I think getting the answers to them will help me use them more effectively and not waste effort using them with settings that end up having no effect.
My main question is about weight zones. What exactly does the weight percentage tell x264 to do? This is never actually specified anywhere. The way I'm thinking, the best thing for x264 to do would be to take the percentage, and whatever bitrate a zone would have gotten using the curve compression assuming there are no zones at all, it boosts that bitrate by the percentage and makes sure the zone gets that much bitrate (unless it's impossible due to maxing out the codec). Is this anything like how x264 behaves?
I've also got a question about how the quantizer zones work. Do quantizer zones force every frame to be that quant, or does it just hover around that quant and give every frame one that is on or very close to it, or is that just the average quant for the entire zone?
My last question is, do all zones force a keyframe, or just an I-frame?
My main question is about weight zones. What exactly does the weight percentage tell x264 to do? This is never actually specified anywhere. The way I'm thinking, the best thing for x264 to do would be to take the percentage, and whatever bitrate a zone would have gotten using the curve compression assuming there are no zones at all, it boosts that bitrate by the percentage and makes sure the zone gets that much bitrate (unless it's impossible due to maxing out the codec). Is this anything like how x264 behaves?
I've also got a question about how the quantizer zones work. Do quantizer zones force every frame to be that quant, or does it just hover around that quant and give every frame one that is on or very close to it, or is that just the average quant for the entire zone?
My last question is, do all zones force a keyframe, or just an I-frame?