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Belgabor · 19th March 2003, 16:29

To my knowledge all MPEG4 codecs use YV12 color format internally, which makes the true value 12 bit, regardless what windoze chooses to report. (That's why it shouldn't matter at all if you process at '16 bpp' or '24 bpp' for compressibility)
16 bit RGB can be easily noticed on gradients, but 12bit YV12 or 16bit YUY2 are completely diffrent things, since these values are the middle bits/pixel over the entire video, if you look at a single pixel its 24 bit(*), only two(YUY2) or four(YV12) adjacent pixels share the same values in the chroma planes.

(*) This is not completely true since valid streams may not have the full value range per channel (e.g. iirc 16-235 for luma).

19th March 2003, 16:29	#12 \| Link
Belgabor VDubMod Devel Join Date: Oct 2001 Location: Germany Posts: 824	To my knowledge all MPEG4 codecs use YV12 color format internally, which makes the true value 12 bit, regardless what windoze chooses to report. (That's why it shouldn't matter at all if you process at '16 bpp' or '24 bpp' for compressibility) 16 bit RGB can be easily noticed on gradients, but 12bit YV12 or 16bit YUY2 are completely diffrent things, since these values are the middle bits/pixel over the entire video, if you look at a single pixel its 24 bit(), only two(YUY2) or four(YV12) adjacent pixels share the same values in the chroma planes. () This is not completely true since valid streams may not have the full value range per channel (e.g. iirc 16-235 for luma). __________________ VirtualDubMod [SourceForge : Tracker/DL] (FAQ, Some rules) Be sure to also download the latest DLL package or get the all inclusive package! Before you post questions, please read the VirtualDub and/or VirtualDubMod FAQ. If you have a bug report or feature request for VirtualDubMod, be sure to read the rules first. We give 100% of your donations to the Open Source community Last edited by Belgabor; 19th March 2003 at 16:32.