UIImage averageColor

- (UIColor *)averageColor
{
    CGImageRef rawImageRef = [self CGImage];

	CFDataRef data = CGDataProviderCopyData(CGImageGetDataProvider(rawImageRef));
    const UInt8 *rawPixelData = CFDataGetBytePtr(data);

    NSUInteger imageHeight = CGImageGetHeight(rawImageRef);
    NSUInteger imageWidth  = CGImageGetWidth(rawImageRef);
    NSUInteger bytesPerRow = CGImageGetBytesPerRow(rawImageRef);
	NSUInteger stride = CGImageGetBitsPerPixel(rawImageRef) / 8;

    unsigned int red   = 0;
    unsigned int green = 0;
    unsigned int blue  = 0;

	for (int row = 0; row < imageHeight; row++) {
		const UInt8 *rowPtr = rawPixelData + bytesPerRow * row;
		for (int column = 0; column < imageWidth; column++) {
            red    += rowPtr[0];
            green  += rowPtr[1];
            blue   += rowPtr[2];
			rowPtr += stride;

        }
    }
	CFRelease(data);

	CGFloat f = 1.0f / (255.0f * imageWidth * imageHeight);
	return [UIColor colorWithRed:f * red  green:f * green blue:f * blue alpha:1];
}