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madness
26th May 2004, 15:07
hi all,
I've got xvid 1.0 and I'm trying to encode a video with 400kbps encode using cbr mode. I was using the older codec before I upgraded it, the file size is about 90mb or so, but now for xvid 1.0 it gave me the file size of ~250mb and even with quantzation of 2,31,2,31,2,31 and I have no idea what on earth is going, so is there any solution I can sort this problem out.

Thanks

jon.schaffer
26th May 2004, 15:20
What is the 90MB-file bitrate?
What is the 250MB-file bitrate?
(the question is: was the first one undersized or is the new one oversized?)

What version was the older codec?

And maybe, could you give more deatils about the settings (default/personnal ones?)


Jon

madness
26th May 2004, 15:59
Originally posted by jon.schaffer
What is the 90MB-file bitrate?
What is the 250MB-file bitrate?
(the question is: was the first one undersized or is the new one oversized?)

What version was the older codec?

And maybe, could you give more deatils about the settings (default/personnal ones?)


Jon
when ever I make a 400 cbr encode, i always end up the file size at 90mb and thats was ok because I've done it alot of times. but with xvid v1.0 and did a 400 cbr encode and the file was oversize and i was quite suprised and i was trying to understadn why is doing it so I change the qunatization slightly. the old codec I mention in my previous post its the 24th june 03 kopei's build.

the settings I uses is:
Encode Type: CBR
Target bitrate: 400
montion search: 0
VHQ: 0
Frame drop ratio: 0
Max I-frame interval: 300
Quantization: 2,12,2,12,2,12 (that my usual quantz I use for all my encode)
Auto detect optimization
fourcc useD: DX50
Quantz Type: H.263
and left the zone option to default.
With those settings my CBR 400kbps encode came out at 90mb and that is good enough, but now i get the size of ~250mb.
Thanks

stephanV
26th May 2004, 16:14
it would be useful if you told us the characteristics (not encoding settings) of the files you obtained by encoding with XviD; most importantly bitrate for both audio and video and the filelenght. use for example GSpot or VirtualDub to get this info.

encoding with 400 kbps does not guarantee a filesize of 90 MB or 250 MB. roughly you can say: filesize = (bitrate of audio + bitrate of video) * filelength.

the cause of the different file size could be so many things, even using a different audio compression could cause it. Without knowing the characteristics of a 90 MB file and a 250 MB file there is no way of telling for anyone what the difference really is.

Sharktooth
26th May 2004, 16:17
Have you properly installed xvid 1.0 (that means you have to uninstall the previous one before installing 1.0)?

jon.schaffer
26th May 2004, 16:21
Originally posted by madness
when ever I make a 400 cbr encode, i always end up the file size at 90mb and thats was ok because I've done it alot of times.

To be sure... do you mean that you usually make encodings with these settings and are confused with a new encoding?
Or do you mean that you encoded the same clip with these two codec versions?

Jon

And please: give - at least - the clips bitrates (VirtualDub -> informations)

madness
26th May 2004, 19:17
@stephanV
ok I've done what you have said and heres the source video details:
filesize: 331mb
bitrate: 1844kbps
4cc is WMV3
23mins and 25seconds long
29.97fps
res: 704x476

Audio is:
128kbps @ 48000 hz

@ Sharktooth
I've uninstall my xvid codec before i install the versiob v1.0 ofc

@jon.schaffer
Yes, I make CBR encode using those settings I posted in my previous posts, but in terms of different settings where its layed out is not much of a difference between thethe older version of xvid and the newest one.
I asked one of my friend and he told me that the bitrate calculator might be broken but he's not sure for definate though.
Thanks

virus
26th May 2004, 19:38
Originally posted by madness
motion search: 0
VHQ: 0
here's the culprit: motion search precision 0 encode a file all made up of keyframes (much bigger than P/B frames). Set it to 6 (and maybe set VHQ to 1) and it should be OK.

virus

madness
26th May 2004, 19:51
ah ok i'll try motion search @ 1 and VHQ @ 1 then
Thanks

stephanV
26th May 2004, 19:52
virus is right... sorry i missed that madness...

just set motion search at 6, it really wont hurt.

madness
26th May 2004, 20:49
ah when i changed the motion search and the vhq and it was fixed.
thanks alot guys