Pink croppadd border instead of black border in 10b

I entered this in custom libvlc options '--video-filter=croppadd{paddbottom=80}' the result is pink border instead of black. Please enlighten me on how to change the border color from pink to black.This occurs during playback of 10bit Hevc videos Thanks

Edited Apr 13, 2020 by Jean-Baptiste Kempf

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