画像の色空間の種類

NSImageクラスである画像が、RGBかCMYKかを知る方法

    /* color space Check
     *  ex:http://lists.apple.com/archives/cocoa-dev/2003/Nov/msg02080.html
     */
    NSString *colorSpaceName = [img colorSpaceName];
    if ([colorSpaceName compare:NSCalibratedRGBColorSpace] == 0) {
        pixelLength = 3;
    } else if ([colorSpaceName compare:NSDeviceRGBColorSpace] == 0) {
        pixelLength = 3;
    } else if ([colorSpaceName compare:NSDeviceCMYKColorSpace] == 0) {
        pixelLength = 4;
    } else {
        NSLog(@"lapBit.m : error: unknown color space [%@]", colorSpaceName);
    }

参考:http://developer.apple.com/documentation/Cocoa/Reference/ApplicationKit/Miscellaneous/AppKit_Constants/Reference/reference.html#//apple_ref/doc/c_ref/NSCalibratedWhiteColorSpace