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View Full Version : Question about quantizers..

MoonWalker
8th March 2002, 23:57
I see tha the default quantizers of XviD are 1-31..Does XviD allow 1x as quantizer? I that from 2x an up are allowed..So for example can I set I-Frames quant to 1 - 1??

MoonWalker
Koepi
9th March 2002, 00:08
Yupp.
MoonWalker
9th March 2002, 00:20
Yupp.

Thanks for your answer..If I encode a movie with quant 1 will it be playable??

*TIP* @ Koepi : Maybe you can put this question into the XOE..:)

MoonWalker
Teegedeck
9th March 2002, 00:23
Originally posted by MoonWalker


Thanks for your answer..If I encode a movie with quant 1 will it be playable??

Yep.
MoonWalker
9th March 2002, 00:28
Yep.

Such great answers with so much meaning...:D

Thanks guys...Keep up the good work


MoonWalker
kythorn
9th March 2002, 00:42
For what it's worth... I've never actually been able to tell the difference between a frame encoded at quant=2 and a frame at quant=1, except by the fact that the quant=1 is often 5 times as large.
saVe
9th March 2002, 00:59
a small note: quant 1 needs very much cpu power. i tried a small clip with quants restricted to 1-1, and it was kind of a slide show, allthough i didn't use any post processing.
Acaila
9th March 2002, 11:31
A quant of 1 would be usefull for lossless compression, but for backing up it wastes way too much space. Better to set the quant range to 2-31 instead of 1-31 for precaution.
OUTPinged_
10th March 2002, 13:47
Acaila, does quant1 really produce lossless compression frames?


(got some frames that looked bad at CL2 a week ago, so that may be actually usefull)
-h
10th March 2002, 13:55
does quant1 really produce lossless compression frames?

Nope. It's close, but certainly not lossless.

(got some frames that looked bad at CL2 a week ago, so that may be actually usefull)

Can you post a screenshot of original vs. encoded? Quant=2 is very accurate, so it seems more likely that you've found a bug, rather than quantization noise.

-h
philippas
10th March 2002, 22:15
Quant 1-1 is great for video capture. Also if you use quant 1-X it's very difficult to max out the codec thus the filesize is very predictable.

For what it's worth... I've never actually been able to tell the difference between a frame encoded at quant=2 and a frame at quant=1, except by the fact that the quant=1 is often 5 times as large.
Well encode a movie with water(i.e waterworld) and you will see the difference.(if of course the source is good)