Bug 475843

Summary:	CMYK Adjust effect values for Reds, Yellow, and Magentas are inverted (negatives increase, positives decrease intensity)
Product:	[Applications] kdenlive	Reporter:	Bernd <berndmj>
Component:	Video Effects & Transitions	Assignee:	Jean-Baptiste Mardelle <jb>
Status:	CONFIRMED ---
Severity:	normal	CC:	diekuhrannte
Priority:	NOR
Version First Reported In:	23.08.1
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Bernd 2023-10-19 19:59:15 UTC

SUMMARY
CMYK Adjust effect (avfilter.selectivecolor) values for Reds, Yellows and Magentas are inverted: positive values reduce the color intensity/saturation, negative values increase it

STEPS TO REPRODUCE
1. Create a red, a yellow and a magenta color clip
2. Apply a CMYK effect and change the values for Reds, Yellows, and Magentas, respectively

OBSERVED RESULT
Positive values decrease saturation, negative values increase

EXPECTED RESULT
the other way around

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Pop!_OS 22.04
KDE Frameworks Version: 5.92
Qt Version: 5.15.3

ADDITIONAL INFORMATION
MLT 7.20.0

Comment 1 diekuhrannte@web.de 2023-10-28 10:14:46 UTC

Yes, the error is exactly as described here.
However, you can still use this effect without restrictions, you just have to know that the sliders work the other way around for Reds, Yellows and Magentas.