使用CGImageMaskCreate应用图像遮罩时发生内存泄漏/ imageWithCGImage

Question

如果有人可以告诉我为什么会出现此代码泄漏？

UIGraphicsBeginImageContext(drawingImage.frame.size); 

    [drawingImage.image drawInRect:CGRectMake(0, 0, drawingImage.frame.size.width, drawingImage.frame.size.height)]; 
    // Draw some vectorial data 
    // ... 
    // Apply an image mask 
    CGImageRef maskRef = mask.CGImage; 
    CGImageRef cgmask = CGImageMaskCreate(CGImageGetWidth(maskRef), 
              CGImageGetHeight(maskRef), 
              CGImageGetBitsPerComponent(maskRef), 
              CGImageGetBitsPerPixel(maskRef), 
              CGImageGetBytesPerRow(maskRef), 
              CGImageGetDataProvider(maskRef), NULL, false); 

    CGImageRef masked = CGImageCreateWithMask([UIGraphicsGetImageFromCurrentImageContext() CGImage], cgmask); 
    CGImageRelease(cgmask); 

    drawingImage.image = [UIImage imageWithCGImage:masked]; 

    UIGraphicsEndImageContext(); 

Answer 1

“蒙面”不会被释放，一旦你用它创建的映像，你需要释放它

drawingImage.image = [UIImage imageWithCGImage:masked]; 
CGImageRelease(masked)