nsbitmapimagerep

How to convert NSImage to NSBitmapImageRep? I have code: - (NSBitmapImageRep *)bitmapImageRepresentation { NSBitmapImageRep *ret = (NSBitmapImageRep *)[self representations]; if(![ret isKindOfClass:[NSBitmapImageRep class]]) { ret = nil; for(NSBitmapImageRep *rep in [self representations]) if([rep isKindOfClass:[NSBitmapImageRep class]]) { ret = rep; break; } } if(ret == nil) { NSSize size = [self size]; size_t width = size.width; size_t height = size.height; size_t bitsPerComp = 32; size_t bytesPerPixel = (bitsPerComp / CHAR_BIT) * 4; size_t bytesPerRow = bytesPerPixel * width; size_t

I don't understand really well the premultiplied alpha. I need a NSBitmapImageRep without alpha channel (I don't need a particular bpp). My problem is that this code give me errors: NSSize imageSize = NSMakeSize(200, 200); //create a non-alpha RGB image rep with the same dimensions as the image NSBitmapImageRep* bitmap = [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:NULL pixelsWide:imageSize.width pixelsHigh:imageSize.height bitsPerSample:8 samplesPerPixel:3 hasAlpha:NO isPlanar:NO bitmapFormat:NSAlphaNonpremultipliedBitmapFormat bytesPerRow:(3 * imageSize.width) bitsPerPixel:24]; //lock

I have a CALayer ( containerLayer ) that I'm looking to convert to a NSBitmapImageRep before saving the data out as a flat file. containerLayer has its geometryFlipped property set to YES, and this seems to be causing issues. The PNG file that is ultimately generated renders the content correctly, but doesn't seem to takes the flipped geometry into account. I'm obviously looking for test.png to accurately represent the content shown to the left. Attached below is a screenshot of the problem and the code I'm working with. - (NSBitmapImageRep *)exportToImageRep { CGContextRef context = NULL;

I'm doing some operations on images and after I'm done, I want to save the image as PNG on disk. I'm doing the following: + (void)saveImage:(NSImage *)image atPath:(NSString *)path { [image lockFocus] ; NSBitmapImageRep *imageRepresentation = [[NSBitmapImageRep alloc] initWithFocusedViewRect:NSMakeRect(0.0, 0.0, image.size.width, image.size.height)] ; [image unlockFocus] ; NSData *data = [imageRepresentation representationUsingType:NSPNGFileType properties:nil]; [data writeToFile:path atomically:YES]; } This code is working, but the problem is with retina mac, if I print the NSBitmapImageRep