I am writing a small video viewing application using xvideo, and I was 
curious as to if there was an explanation page about some of the video 
formats.  I am using an nvidia card.  Here is some sample output from the 
video device querying routine
(XvQueryAdaptors):

Format: 0x59565955 YUV LSBFirst GUID: UYVY bpp 16 packed ys 8 us 8 vs 8, hyp 
1 hup 2 hvp 2 vyp 1 vup 1 vvp 1.  
This is a direct print of the struct filled in, with the names of a few of 
the variables switched.  Now, I appreciate that much information, but it does 
not tell me enough.  Its guid tells you what the format really is, and it 
works with the v4l2 uyvy pixel format.   

Now, I like to compress stuff on the side, and I like to use yuv420 because 
it is ~half the size of a comparable rgb image, and it is a planar format 
(i.e. works well w/ jpeg).  Here are the two planar formats, again with 
shortened descriptions:
Format: 0x30323449 YUV LSBFirst GUID: I420 bpp 12 planar
ys 8 us 8 vs 8, hyp 1 hup 2 hvp 2 vyp 1 vup 2 vvp 2

Format: 0x32315659 YUV LSBFirst GUID: YV12 bpp 12 planar
ys 8 us 8 vs 8, hyp 1 hup 2 hvp 2 vyp 1 vup 2 vvp 2

The periods are correct, but when I tried the first format with a YUV420 
format image, the picture looked almost completely incorrect.  The second may 
work, I will try it soon, but why did the first one not work?  

I imagine that the part 'GUID: I420' tells me everything I need again.  
Probably, the UV planes need to be first in memory, followed by the Y plane 
(the I is probably for Inverted).   

But other than the GUID, nothing tells me as much.  Where is the concrete 
description so that I REALLY know what is going on?  I want a map of where 
the card expects that data to be in memory, so that I can hook it up.  The 
extension works GREAT when it works, but without more information on the 
formats that the system is expecting, it becomes a tough process to play with 
the system.  Is this something that needs to be written (if so, I wouldn't 
mind doing tests till I found out what the four formats were for).  

Basically, it would be nice if xvideo extension had a page as thorough with 
its format descriptions as http://www.thedirks.org/v4l2/v4l2fmt.htm, the 
video for Linux 2 API pixel format description page.  That would be supa.

So that was my xpert question, here is a newbie xlib question.  Window 
managers don't realize that my application can be closed.  They either don't 
display the close icon, or they do and when they close the application, they 
just annihilate it.  They never have the close option highlighted.  Does 
anyone know how to fix the problem?  I think it has to do with the flags 
passed in, probably the event masks passed in to XCreateWindow.  But hell if 
I know.  Any ideas?  Thanks a LOT for you help, greatly appreciated.  
Chris
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