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ehsan2004
11-15-2004, 12:35 PM
Hi
Assume that we have adjusted the value of ML_IMAGE_SAMPLING_INT32 to ML_SAMPLING_422. So In this case, Cb and Cr are interleaved on the 1st
channel. Assume that we have adjusted the value of ML_IMAGE_PACKING_INT32 to M_PACKING_10. So it's in this order:
bbbbbbbbbbYYYYYYYYYYrrrrrrrrrrAA.My problem is that with this order we haven't interlaced the Cb and Cr in the 1st channel.I think that we need this order for this example: bbbbbrrrrrYYYYYYYYYY000000000000 and i think that the ML_PACKING_10 creates an error for this case.If it's true, how can i create the second order( bbbbbrrrrrYYYYYYYYYY000000000000 )?

fjaubert
11-17-2004, 05:48 AM
Hello Ehsan,

In 422 sampling, Cb and Cr are *interleaved* (not interlaced), meaning they alternate on a per-pixel basis. So if one pixel carries Cb information, the next will carry Cr information, and the next will carry Cb again, and so on.

So with 10-bit per component in a 32-bit pixel packing, you would get a sequence like this:
bbbbbbbbbbYYYYYYYYYY0000000000AA
rrrrrrrrrrYYYYYYYYYY0000000000AA
bbbbbbbbbbYYYYYYYYYY0000000000AA
rrrrrrrrrrYYYYYYYYYY0000000000AA
...etc...

ehsan2004
04-19-2005, 06:29 PM
Hi Fabrice
I want to put all the colorspace, packing and sampling concepts together and make some questions.
If we use from the 10_10_10_2_R packing and CbYCrA colorspace, then we have the following shape:
AArrrrrrrrrrYYYYYYYYYYbbbbbbbbbb
If we use from the 4:2:2 sampling, Cb and Cr are interleaved on the 1st channel, and Y occupies the 2nd channel.What's the meaning of the *first channel* and *second channel* in this case?
What about the case that we use from the 10_10_10_2_1432 packing?What's the meaning of the first and second channels in this case?
In general, How can we specify the first, second, third and fourth channels?is there a relation between the channels and components?
-Ehsan-