Making an image NSCalibratedWhiteColorSpace
Making an image NSCalibratedWhiteColorSpace
- Subject: Making an image NSCalibratedWhiteColorSpace
- From: Gideon King <email@hidden>
- Date: Tue, 13 Nov 2001 22:51:43 +0800
I need to use an image with just grayscale and alpha in it for image
processing.
To create the image, I need to do some drawing, so I use an image with
and NSCustomImageRep to do the drawing. I tell that image rep to be
NSCalibratedWhiteColorSpace. I then lock focus on the image and use
initWithFocusedViewRect: to get the bitmap data. This always returns an
image rep with RGBA color in NSCalibratedRGBColorSpace. If I then set it
to NSCalibratedWhiteColorSpace, it doesn't do any conversion for me -
just leaves it as 4 samples per pixel (RGBA).
Will I need to do the conversion manually, or is there some way that
will allow me to get a grayscale alpha image directly?
TIA
Gideon.