Michael Schimek requested the addition of inverted alpha framebuffer
caps/flags to support such hardware.
'Normal' alpha uses this formula to mix the framebuffer and video:
output = fb pixel * fb alpha + video pixel * (1 - fb alpha)
and the 'inverted' alpha uses this formula:
output = fb pixel * (1 - fb alpha) + video pixel * fb alpha
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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