>    In the Windows world all anyone needs to know is the fourcc code
> (or the GUID).  The format is unambiguously defined by this (at least
> the YUV formats are).  Nobody uses anything other than this.
>
>    These are industry standard formats.  Documented in many places on
> the web.  Such as:
>
>    http://www.webartz.com/fourcc/



1. Never programmed video in Windows.
2. ass-umed that GUID meant Globally Unique Identifier, not fourcc code (They 
looked particular, perhaps should have followed that up a bit more).
3. You are definitely correct.  That web page tells me everything I could 
ever want.  

>    Despite this, the  vImageFormatValues spells all of this out
> in excruciating detail.  I don't understand what problem you are having.

No it does not.  It does not explain where the actual data needs to be.  
Example, UYVY needs a byte of U, followed by a byte of Y, followed by a byte 
of V, followed by a byte of Y.  That is pretty self explanatory, perhaps.  
YV12 needs a plane of y, a plane 1/4 size of v, a plane 1/4 size of u.  The 
two period values, horizontal then vertical for each yuv tell you everything 
you need to know about the size of the planes, but what about if there is 
padding in the Y plane (some capture devices will do that)?  Also, YV12 seems 
to indicate that there is only a y and v plane, although you could guess that 
there is a U plane somewhere, and if there was then the component order would 
let you know where it would be.  

The point is that unless you are familiar with the fourcc code, then the 
structure does *not* tell you everything you need to know.  It tells you a 
LOT, but not everything. 

Nobody in the windows world may use anything other than this, but video 
capture on a linux system is done using the video for linux api's (at least 
if you are using a bt878 card).  Thus when they look at the struct, they 
don't realize the guid is anything but a guid, perhaps relative to X windows, 
perhaps really globally unique in the sense of video playback on all systems, 
 etc.

What you have told me, however, is more that enough to complete whatever it 
is I am messing with.  Perhaps I should write a small tutorial or something 
of that sort so that this question is not asked twice.  



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