FixLuminance: Difference between revisions
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::Maximum darkening (at top line) = {{FuncArg|intercept}} / {{FuncArg|slope}} | ::Maximum darkening (at top line) = {{FuncArg|intercept}} / {{FuncArg|slope}} | ||
The purpose of this filter is to progressively darken the top of the image; for example, to compensate for certain VCRs which make the top of each frame brighter than the bottom. This filter works only with [[YUY2]] input. | |||
==== Examples ==== | |||
*Progressively darken top lines. | |||
<div {{BoxWidthIndent|48|2}} > | |||
[[ColorBars]](pixel_type="YUY2") | |||
[[Crop]](0, 0, 0, 256) | |||
FixLuminance(100, 4) | |||
[[File:FixLuminance1.png]]<br> | |||
Line 99 is normal; line 0, the topmost line, is darker by 25 ({{FuncArg|intercept}}/{{FuncArg|slope}} = 100/4 = 25) | |||
</div> | |||
*Make a ''ramp'' test image. | |||
<div {{BoxWidthIndent|48|2}} > | |||
[[BlankClip]](height=256, pixel_type="YUY2", color_yuv=$ff8080) | |||
FixLuminance(255, 1) | |||
[[File:FixLuminance2.png]] | |||
</div> | |||
[[Category:Internal filters]] | [[Category:Internal filters]] | ||
[[Category:Levels_and_Chroma_filters]] | [[Category:Levels_and_Chroma_filters]] | ||
Revision as of 03:51, 17 January 2016
FixLuminance(clip clip, int intercept, int slope)
- int intercept = (required)
- Line at which to start correction.
- int slope = (required)
- Slope of correction function. The top of the picture is made darker by 1 (on a 0-255 scale) every slope lines.
- Maximum darkening (at top line) = intercept / slope
The purpose of this filter is to progressively darken the top of the image; for example, to compensate for certain VCRs which make the top of each frame brighter than the bottom. This filter works only with YUY2 input.
Examples
- Progressively darken top lines.
ColorBars(pixel_type="YUY2") Crop(0, 0, 0, 256) FixLuminance(100, 4)
Line 99 is normal; line 0, the topmost line, is darker by 25 (intercept/slope = 100/4 = 25)
- Make a ramp test image.
BlankClip(height=256, pixel_type="YUY2", color_yuv=$ff8080) FixLuminance(255, 1)
