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View Full Version : Wondering how to tweak decode brightness/contrast/levels on VirtualDub


gheller
8th July 2015, 15:56
Hey all!

Having trouble with some video I'm importing into VirtualDub created on a DVD recorder. It's a VOB and I'm using fccHandler's MPEG plugin to read the file. In the preview window which is an overlay with hardware decoding the video looks fine, but in the output window where software decoding is used, the video is darker. I can use virtualdub filters to increase the brightness, but at that point the dark end of the spectrum has already been lost, and along with it, all detail in any dark scenes. Is there any way for me to tweak the settings for the software MPEG decoder so it behaves more like the hardware decoder and doesn't lose the darks? If not, are there settings stored in the .VOB file I could mess with that might also fix the problem, and if so, where are they stored?

--Gabe Heller

shekh
8th July 2015, 16:39
Hi, wrong levels are typical from misinterpreted color range. I am not sure about VOB format, but if the range is specified in the file, and ffmpeg handles it, then my plugin should work correctly: http://sourceforge.net/projects/vdcachingdriver/

Otherwise you can add internal filter "alias format" and select color range (and color space) manually.

raffriff42
8th July 2015, 20:49
Very interesting, shekh. I see this driver is included with your VirtualDub FilterMod (https://sourceforge.net/projects/vdfiltermod/) project, which incorporates the driver seamlessly - and has some nice new plugins (Gaussian blur! Histogram overlay! LAB color correction! Motion blur! Perspective warp!) and other features (deep color! alpha support!)

gheller
8th July 2015, 21:21
I had to upgrade to a more recent version of Virtualdub that has the alias filter, and experiment with the settings a bit. Setting the 'component range' to "full' seems to do the trick. Thanks a bunch!

shekh
8th July 2015, 22:14
Motion blur! Perspective warp!

What? :) If you mean internal filters, these are untouched from official VirtualDub.

Mounir
14th July 2015, 00:56
You better use avisynth with avspmod and also dgindex to create a .d2v for the vob
you can tweak the levels with y levels and tweak the brightness, contrast, saturation with tweak


MPEG2Source("Myvideo.d2v",
ylevels(0,1.000,255,16,235)
tweak( cont=1.1, sat=1.0,coring=false)