February 2006

How to save a bitmap as a 8-bit gray scale PNG file with Cocoa ?

When creating a 8-bits gray scale off-screen image by manually drawing in it,
it always turn out to be a 24-bits one when saved to disk using:
- (NSData *)representationUsingType:(NSBitmapImageFileType)storageType properties:(NSDictionary *)properties.

Any clue ?

Detecting frontmost application changes…

How to detect frontmost application changes ?