Get the pixels of an UIImage

UIImage+getPixels.m

@implementation UIImage (BCGetPixels)
-(void)bc_getPixels:(char*)pixels;
{
    CGImageRef imageRef = self.CGImage;
    NSUInteger width = CGImageGetWidth(imageRef);
    NSUInteger height = CGImageGetHeight(imageRef);
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceGray();
    NSUInteger bytesPerPixel = 1;
    NSUInteger bytesPerRow = bytesPerPixel * width;
    NSUInteger bitsPerComponent = 8;
    CGContextRef context = CGBitmapContextCreate(
    	pixels, 
      width, height,
      bitsPerComponent,
      bytesPerRow,
      colorSpace,
      kCGImageAlphaNone
    );
    CGColorSpaceRelease(colorSpace);

    CGContextDrawImage(context, CGRectMake(0, 0, width, height), imageRef);
    CGContextRelease(context);
}

@end