Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
371 views
in Technique[技术] by (71.8m points)

iphone - Making a UIImage to a circle form

I have been trying to mask a UIImage into a circle. I'm using now the code that has been popular on other answers here, but although I do get a circle its edges are very jagged and not smooth. Anyone can help? I do I get a perfect, smooth circle?

The code I'm using to create the mask is:

  (UIImage*) maskImage:(UIImage *)image withMask:(UIImage *)maskImage {

    CGImageRef imageNoAlpha = image.CGImage;

    CGColorSpaceRef cs = CGColorSpaceCreateDeviceRGB();

    CGFloat width = CGImageGetWidth(imageNoAlpha);
    CGFloat height = CGImageGetWidth(imageNoAlpha);

    CGContextRef ctxWithAlpha = CGBitmapContextCreate(nil, width, height, 8, 4*width, cs, kCGImageAlphaPremultipliedFirst);

    CGContextDrawImage(ctxWithAlpha, CGRectMake(0, 0, width, height), imageNoAlpha);

    CGImageRef imageWithAlpha = CGBitmapContextCreateImage(ctxWithAlpha);

    CGImageRef maskRef = maskImage.CGImage; 

    CGImageRef mask = CGImageMaskCreate(CGImageGetWidth(maskRef),
                                        CGImageGetHeight(maskRef),
                                        CGImageGetBitsPerComponent(maskRef),
                                        CGImageGetBitsPerPixel(maskRef),
                                        CGImageGetBytesPerRow(maskRef),
                                        CGImageGetDataProvider(maskRef), NULL, false);

    CGImageRef masked = CGImageCreateWithMask(imageWithAlpha, mask);

    UIImage* retImage= [UIImage imageWithCGImage:masked];
    UIImage* retImageFixed = [retImage transparentBorderImage:1];

    CGImageRelease(mask);
    CGImageRelease(masked);
    CGImageRelease(imageWithAlpha);
    CGContextRelease(ctxWithAlpha);
    CGColorSpaceRelease(cs);

    return retImageFixed;

Thanks in advance...

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

try this code

yourImageView.layer.cornerRadius = yourImageView.frame.size.height /2;
yourImageView.layer.masksToBounds = YES;
yourImageView.layer.borderWidth = 0;

this show image like ios 7 circle image thanks


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...