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octapus
23rd February 2002, 22:25
I was doing a second pass with stats which was curve-scaled in GuardianKnot and got a 0% weight on credits.
So i did the 2nd pass with external method (modulated) but i put a constraint on Intra frames with values 2-4.
When movie finished main body and got to the end where credits were there were some stange things happenning, maybe because of the constraint because inter values were usually from 21 to 31 and when suddenly (every 200 frames) an intra frame was formed it took a vale greater than 31. I saw values like 35,39,56,69,45 e.t.c
Watching the movie afterwards there were problems on those specific parts.

Now normally there shouldn't be any frames (inter or intra) bigger than 31.
Largest quantizer value given in XVID Coded Dialog box was 31. And even if there were something wrong there, the codec itself puts maximum value to 31 from what i saw in the sources.
This is the first time something like this has happened but also the first time using consteraints on a guradianknot-edited stats.

P.S I was using Koepi's 17 February binaries.

-h
24th February 2002, 00:54
Hrm that is a problem. I'll have a look.

-h

Franko30
25th February 2002, 00:34
Originally posted by octapus
when suddenly (every 200 frames) an intra frame was formed it took a vale greater than 31. I saw values like 35,39,56,69,45 e.t.c
Watching the movie afterwards there were problems on those specific parts.


P.S I was using Koepi's 17 February binaries.

I noticed the same thing - (normal) quantizer settings 1-16 - I-frame quant lock 1-6, quant smoothing enabled.

But it only happens in the credits sections when using a value below 12% or so for the credits.

I am using Koepi's Feb17th build, too.

Didn't report it earlier, as I really didn't notice it while watching the credits - only when using Debugview, so I thought it's not such a big deal (thought that other builds without this will follow as everything changes all the time).

Apart from that: Very nice encodings done on every movie so far!

Frank

Koepi
25th February 2002, 00:46
OOpsi :)

I turned of the whole intra frame checking for end credits. I guess I have to reset the values when in credits, it's simple as that.

I'll look maybe tomorrow into it...

Regards,
Koepi

-h
25th February 2002, 10:05
This is a problem - encoder.c only clamps the quantizer values at codec creation stage, so odd things would be going on.

I've fixed this, but am waiting on committing due to a whole lot of other "stuff" that is going in..

-h