fix(yuv): set luma offset default to 0 for proper scale behavior - #679
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for13to1 wants to merge 1 commit into
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fix(yuv): set luma offset default to 0 for proper scale behavior#679for13to1 wants to merge 1 commit into
for13to1 wants to merge 1 commit into
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When luma offset is 125 (limited range center), adjusting scale only changes contrast without affecting overall brightness. Setting offset to 0 ensures scale adjustments produce visible brightness changes.
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Well this depends a bit on how you want the scale to work. By default, YUView scales around the middle point which basically extends the gamma. If this is not what you expect, then you can change the offset in the UI to 0 or 255 or whatever your preference is. But I don't think that 0 should be the default. |
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fix(yuv): set luma offset default to 0 for proper scale behavior
Problem
Luma scale adjustment has no visible effect on image brightness.
Root Cause
Default Luma offset is 125 (limited range center). Transform formula
newValue = (value - offset) * scale + offsetuses offset as pivot, so pixels near 125 are minimally affected.Solution
Changed default Luma offset from 125 to 0, so scale adjustments affect all pixels proportionally.
Changes
videoHandlerYUV.cpp: Updated 3 locations (constructor, setSrcPixelFormat, calculateDifference)Effect