Quote:
Originally Posted by sirt
Yes but I don't really know what quantizers will help to obtain the final size intended by the bitrate setted. What I'm sure is that letting 1,31/1,31/1,31 will result in the poorest quality possible ; at least, it's what I read on a web guide where they advise to use 1,4/1,16/1,8 but I ignore why.
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The limits there don't really help with anything; they just limit what the rate control can use. Because quant 1 is
much larger than quant 2 and not really any better looking I actually like using 2,31 as min,max. This gives Xvid the freedom to use whatever quant it thinks is best but if the file is looking undersized it won't go to the mostly pointless quant 1 just to hit the required bit rate.
IIRC the default was set to 1-31 because less experienced users would complain about undersized files using 2-31. Adding the quant 1 option doesn’t increase the visual quality of the encodes but it does make them larger, preventing angst about undersized files for users.
Remember those are just the min/max. Xvid doesn't have to use any particular quantizer unless it thinks it is the best option to hit a desired file size.
A caveat: I have not used Xvid in several years as x264 has superseded it.