Doom9's Forum - View Single Post - VAQ: Making Xvid's Adaptive Quantization Not Suck

Didée · 23rd February 2008, 03:44

Regarding (2) - AFAIR for DQUANT blocks, QP may not differ more than +/-2 from the previously coded block. So theoretically the full quant range from 1 to 31 can be used in a frame, just the difference between "adjacent" blocks is limited. Dunno, perhaps it's a restriction to make implementations of HW decoders easier? Could also be the reason for not allowing 4mv for DQUANTS, but again dunno.
GMC is "WTF" anyway - major effort, minor gain. There must be a reason GMC isn't in the spec's for AVC ...

23rd February 2008, 03:44	#26 \| Link
Didée Registered User Join Date: Apr 2002 Location: Germany Posts: 5,391	Regarding (2) - AFAIR for DQUANT blocks, QP may not differ more than +/-2 from the previously coded block. So theoretically the full quant range from 1 to 31 can be used in a frame, just the difference between "adjacent" blocks is limited. Dunno, perhaps it's a restriction to make implementations of HW decoders easier? Could also be the reason for not allowing 4mv for DQUANTS, but again dunno. GMC is "WTF" anyway - major effort, minor gain. There must be a reason GMC isn't in the spec's for AVC ... __________________ - We´re at the beginning of the end of mankind´s childhood - My little flickr gallery. (Yes indeed, I do have hobbies other than digital video!)