[FFmpeg-user] Calculating offset of shifted line

[Ulf Zibis]

Hi,

I would like to calculate how much a special line in the video is
irregularly shifted to right or left. For this I want to compare the
line with the adjacent line above by calculating the minimum of the
quadratic mean for each shift.

I'm first looking for something like:
x:=0; y:=123; diff:= 0; while(x++ < in_w, diff += (luma(x,y) - luma(x,y
- 1))²);

So the first question is: how to get the luma value of a pixel?

Thanks

-Ulf

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Von meinem Seibert gesendet