CGImageCreateWithMask works great but the masked out area is black in my resulting image, how can I set it to be white?

Question

I've masked out my image thusly:

    CGImageRef maskRef = [[UIImage imageNamed:@"testMask2.png"] CGImage];

CGImageRef mask = CGImageMaskCreate(CGImageGetWidth(maskRef),
                                    CGImageGetHeight(maskRef),
                                    CGImageGetBitsPerComponent(maskRef),
                                    CGImageGetBitsPerPixel(maskRef),
                                    CGImageGetBytesPerRow(maskRef),
                                    CGImageGetDataProvider(maskRef), nil, YES);

UIImage *image = [UIImage imageWithContentsOfFile:path];

CGImageRef masked = CGImageCreateWithMask([image CGImage], mask);

imageView.image = [UIImage imageWithCGImage:masked];

And it works great, but the resulting image has BLACK where it was masked out, how can I set it to have WHITE where its masked out?

Answer 1

The image is supposed to be transparent where it's "masked out"; the colour you see will depend on what background you're drawing it on.

(I don't remember if there's a requirement that the source image has an alpha channel.)

It may be worth making sure that imageView.opaque = NO.