[Ffmpeg-devel] moving non-SIMD parts of libswscale to LGPL

Luca Abeni lucabe72
Tue Dec 12 10:56:17 CET 2006

Hi Michael,

On Mon, 2006-12-11 at 20:17 +0100, Michael Niedermayer wrote:
> The construction of luminance and colour-difference signals is as follows:
>                                           EY = 0.299 ER + 0.587 EG + 0.114 EB
> so yes, you are correct the values are truncated, but apparently not by mpeg*
> the equations in ITU-R BT.601-5 are simply wrong 0.5/0.701 is not 0.713 for
> example ...
> anyway you should have no difficulty reconstructing the correct values in all
> cases by simply following the same path as above just without the senseless
> rounding
Ok; thanks for the explaination.
I'll redo all my computations based on it (I already tried some of them,
and it seems that the results are much more similar to the numbers
currently contained in Inverse_Table_6_9).

Also, thanks for the comments on the code; I am going to fix all the
issues you highlighted, and I'll have a new version in few days.

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