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BigMing001 / libyuv

Automatically exported from code.google.com/p/libyuv
BSD 3-Clause "New" or "Revised" License
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Remove I411 support #509

Closed GoogleCodeExporter closed 8 years ago

GoogleCodeExporter commented 8 years ago 
411 subsampling is not being used, so propose removing it.
If someone has a reason for keeping it around, speak up now

Original issue reported on code.google.com by fbarch...@google.com on 20 Oct 2015 at 6:29

GoogleCodeExporter commented 8 years ago 
ARGBToI411 test passes on odd widths now.
Subsampling code is a little quirky.
It takes horizontal average with rounding of horizontal ARGB and then 
essentially does ARGBToI422
The I422 subsampling is done by multiplying by matrix coefficients that are 1/2 
the normal coefficients.  They are even numbers, so the math should be the 
same.  It adds those results, then does a rounding shift to convert fixed point 
to bytes.

Original comment by fbarch...@google.com on 21 Oct 2015 at 7:56

GoogleCodeExporter commented 8 years ago

Original comment by fbarch...@google.com on 22 Oct 2015 at 3:04