fOP

[Leon]

@1% :  I still don't understand what this jpslice thing is or actually does, but could it be used to improve the quality of "normal" CBR encoding?  (ie encoding at CBR1.0-1.5x with GOP 12.)  Or do you need to drop the GOP to be able to improve jpslice at all?

Sorry for the tangent, but has anyone tested increasing the GOP to perhaps improve CBR 0.8x, etc?

[Leon]

Right, I have no idea why the forum decided to out this as a new topic – I just went to post on a thread and I suddenly appeared here...

Can't see any way to delete it.. 

[Marsu42]

Right, I have no idea why the forum decided to out this as a new topic

But great topic name that surely will draw attention, maybe it should be a sticky :-) ... and did you check for little gnomes inside you computer lately? :->

[1%]

slice is frame quality. ALL cbr does is set this value up and down and maybe change the deblocking filter.  Watching it, it prefers crappy quality even at Q-16. It does prediction of what to set next based on that whole mess of numbers I size, P size, basically CBR x setting.

gop size is number of compressed P frames in between each I frame. So 3 is IPI and 1 is I and 12 is IPPPPPPPPPPI.
The camera writes every certain number of I frames.

Is that clearer? No point in improving CBR function, better to just write our own and poll the buffer. Old mL CBR wasn't fast enough because there were no cache hacks and could only use the canon function to set qscale and move it by 1, which is waaaaay not enough. Only benefit to longer gop is stronger compression with this implementation.