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Acaila
2nd January 2002, 21:19
I think most of you who are using GKnot will have noticed that the final movie when viewed in explorer says it has 16 bit colors on its properties page. That it is fact a bug of VirtualDub (can anyone confirm this?). If you use VirtualDub in full-processing mode then you're fine, however if you use fast-recompress mode (like GKnot does) then you get an output file with 16 bit colors. It looks completely normal (i.e. like 24 bits), but as far as VirtualDub is concerned it is treated as if it's only 16 bit.

This leads to a problem I am having.
I encode my end credits with some extra filters (coring,logo,tempsmoother) to get the size down drastically. The filters require me to use VDub's full-processing mode.
The rest of the movie I frameserve through Avisynth using all the filters I need from Avisynth internally (tempsmoother,logo) so I can use VirtualDub encoding in fast-recompress mode. So what I end up with is a 24 bit credits with a 16 bit movie. ARGH! :(

Of course these can't be combined anymore. I tried my credits with my Avisynth-method, but with the filters I use my logo gets screwed up when using VDub's fast-recompress.

Anyone have any suggestions, besides going full-processing for the entire movie?

I'm using version 1.4.8 but had the same experience with 1.4.7 as well.

iluminati
2nd January 2002, 23:27
if you have a lot of space you could first encode the credits in vdub in full processing mode with all the filters with a lossless compression like huffyuv. then load this file into vdub, select fast recompress and use the divx codec of your choice.
This way you will have to encode the credits twice, but they are shoert compared to the movie and the second encode is quite fast anyway.

Swede
4th January 2002, 00:45
Why not just edit the depth byte 0x10 to 0x18? (Or the other way around) Open One of the avi's in Tools/Hex edit and the 1.4.8 vDub are able to show you what the fields are for.

The one you look for is the biBitCount (number of bits per pixel, should be right before the string DIV3 at an offset around BA or so) and it probably doesn't matter (correct me if I'm wrong) if you change the credits to 0x10 or the movie to 0x18...

movmasty
18th February 2002, 11:47
ahhhhhhhhhhhh, the exe editor is meant for this!