[vorbis-dev] video compression using textured polygons?

Timothy J. Wood tjw at omnigroup.com
Sun Jan 7 02:22:10 PST 2001

   This seems like an intesting idea...

   So, thinking about the problem it seems that to get edges that look 
really good but still have lot data requirements, you're going to have 
to do alpha blending.

   Imagine a scene where you have a red triangle moving against a 
textured background.  If you just record the verticies of the triangle 
each frame and the corner colors, then when you play back the recording, 
you are going to get ugly pixel noise on the edges as pixels pop from 
the background color to red (or the other way), or you're going to have 
to transmit a bunch of extra data.

   If you have previous frame, however, you could look at how the pixel 
values change as the edge moves over them.  This could lead you to 
determine that the edge is solid and as the edge moves over background 
pixels, they quickly take on the color of the surface attached to that 

   Or, they might take on a function of the color of the surface attached 
to that edge (if you have a translucent surface), for example.  In 
either case, by exploiting frame coherence, you might be able to 
eliminate noise on the edges (or having to transmit extra cleanup data) 
by figuring out whether you can compute the data using alpha blending.


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