UIImageネガティブカラー効果を与える方法

Question

これは私の最初の質問です。
私は私が負の色効果などの画像効果の外観を変更したいアプリを持っている

Answer 1

それはあなたが画像を選択し、以下のコード

UIGraphicsBeginImageContext(renderImage.size); 
CGContextSetBlendMode(UIGraphicsGetCurrentContext(), kCGBlendModeCopy); 
[renderImage drawInRect:CGRectMake(0, 0, renderImage.size.width, renderImage.size.height)]; 
CGContextSetBlendMode(UIGraphicsGetCurrentContext(), kCGBlendModeDifference); 
CGContextSetFillColorWithColor(UIGraphicsGetCurrentContext(),[UIColor whiteColor].CGColor); 
CGContextFillRect(UIGraphicsGetCurrentContext(), CGRectMake(0, 0, renderImage.size.width, renderImage.size.height)); 
renderImage = UIGraphicsGetImageFromCurrentImageContext(); 
UIGraphicsEndImageContext(); 

Answer 2

方法を作るに画像を設定する必要がありますので、簡単です：

- (UIImage *)makeImageNegative:(UIImage *)image{ 
UIGraphicsBeginImageContext(image.size); 
CGContextSetBlendMode(UIGraphicsGetCurrentContext(), kCGBlendModeCopy); 
[image drawInRect:CGRectMake(0, 0, image.size.width, image.size.height)]; 
CGContextSetBlendMode(UIGraphicsGetCurrentContext(), kCGBlendModeDifference); 
CGContextSetFillColorWithColor(UIGraphicsGetCurrentContext(),[UIColor  whiteColor].CGColor); 
CGContextFillRect(UIGraphicsGetCurrentContext(), CGRectMake(0, 0, image.size.width, image.size.height)); 
UIImage *returnImage = UIGraphicsGetImageFromCurrentImageContext(); 
UIGraphicsEndImageContext();  
return returnImage; 
}