fixing brightness

[jarthel]

I have a DVD here and have created a d2v from it.

I then frameserver it using avisynth. Well viewing the original .vob and the .avs files in vdubmod, it seems the .avs is lighter. Is there a way to fix this? If so, how?

Thanks

[Didée]

The *.avs comes out lighter ?

Usually, it's just the other way round: *.avs mostly seems to be too dark. Compare the thread picture too dark with avisynth script (http://forum.doom9.org/showthread.php?s=&threadid=78220).

[Wilbert]

@Didee,

The annoying part is (besides that no one solved the riddle) that I can't replicate it by making artificial mpeg2s.

[jarthel]

please don't hijack my thread. :|

If you want to discuss "too dark" video, please create your own. :|

[fccHandler]

Originally posted by jarthel
please don't hijack my thread. :|
Huh??? We're trying to get to the bottom of the original problem you posted. If you really want a solution, work with us on this. ;)

[sh0dan]

I'm splitting even though it is about the same topic.

New thread... (http://forum.doom9.org/showthread.php?s=&threadid=81191)

@jarthel: You need to identify exactly where you experience the brightness change. AviSynth does no brightness-scaling except when you 1) Ask for at (by a filter) or 2) Convert colorspace (RGB<->YUV).

Since it does neither without you telling it to do so, you have to elaborate/give us som e examples...

[jarthel]

it seems my problem lies with "converttoyuy2()" which is the last script in my avs file.

Is there a way to counter this?

Thanks

[Wilbert]

If you read the other thread you will see where the problem is:

your dvd stream stores mpeg2 coefficients, which should be used during playback (YUV->RGB). AviSynth, VDub, VDubMod (but also DivX/XviD decoders) uses mpeg1 coefficients by default, because it doesn't know that the mpeg2 coefficients should be used for decoding. Something like that ...