iOS高斯模糊&毛玻璃效果

高斯模糊

需要引入<Accelerate/Accelerate.h>类，一般封装到image的分类中，以便使用，下面是代码，其中blur为模糊程度

#import <Accelerate/Accelerate.h>

/**
 高斯模糊
 @param image image
 @param blur (0 - 1 之间)
 @return image
 */
+(UIImage *)boxblurImage:(UIImage *)image withBlurNumber:(CGFloat)blur
{
    if (blur < 0.f || blur > 1.f) {
        blur = 0.5f;
    }
    
    int boxSize     = (int)(blur * 100); //100为最大模糊程度
    boxSize         = boxSize - (boxSize % 2) + 1;
    CGImageRef img  = image.CGImage;
    
    vImage_Buffer     inBuffer, outBuffer;
    vImage_Error      error;
    
    //从CGImage中获取数据
    CGDataProviderRef inProvider = CGImageGetDataProvider(img);
    CFDataRef inBitmapData       = CGDataProviderCopyData(inProvider);
    
    //设置从CGImage获取对象的属性
    void *pixelBuffer;
    inBuffer.width      = CGImageGetWidth(img);
    inBuffer.height     = CGImageGetHeight(img);
    inBuffer.rowBytes   = CGImageGetBytesPerRow(img);
    inBuffer.data       = (void*)CFDataGetBytePtr(inBitmapData);
    pixelBuffer         = malloc(CGImageGetBytesPerRow(img) * CGImageGetHeight(img));
    if(!pixelBuffer)
        NSLog(@"No pixelbuffer");
    outBuffer.data      = pixelBuffer;
    outBuffer.width     = CGImageGetWidth(img);
    outBuffer.height    = CGImageGetHeight(img);
    outBuffer.rowBytes  = CGImageGetBytesPerRow(img);
    error = vImageBoxConvolve_ARGB8888(&inBuffer,
                                       &outBuffer,
                                       NULL,
                                       0,
                                       0,
                                       boxSize,
                                       boxSize,
                                       NULL,
                                       kvImageEdgeExtend);
    if (error) {
        NSLog(@"error from convolution %ld", error);
    }
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    CGContextRef ctx = CGBitmapContextCreate( outBuffer.data,
                                             outBuffer.width,
                                             outBuffer.height,
                                             8,
                                             outBuffer.rowBytes,
                                             colorSpace,
                                             kCGImageAlphaNoneSkipLast);
    CGImageRef imageRef  = CGBitmapContextCreateImage (ctx);
    UIImage *returnImage = [UIImage imageWithCGImage:imageRef];
    
    //清除;
    CGContextRelease(ctx);
    CGColorSpaceRelease(colorSpace);
    free(pixelBuffer);
    CFRelease(inBitmapData);
    CGImageRelease(imageRef);
    
    return returnImage;
}

&毛玻璃效果

毛玻璃效果实现有很多种，大致都是用蒙版的方式实现如toolbar去做蒙版，但是由于toolbar的表现不太好，在对接的地方会出现白边，所以我用iOS8出现的模糊处理类去做蒙版

    //需要做模糊效果的图片
    UIImageView *testView = [[UIImageView alloc]initWithFrame:self.view.bounds];
    [self.view addSubview:testView];

    //实现模糊效果
    UIBlurEffect *blurEffrct =[UIBlurEffect effectWithStyle:UIBlurEffectStyleLight];
    
    //毛玻璃视图
    UIVisualEffectView *visualEffectView = [[UIVisualEffectView alloc]initWithEffect:blurEffrct];
    
    visualEffectView.frame = self.view.bounds;

    //设置透明度
    visualEffectView.alpha = 0.9;
    
    [self.view addSubview:visualEffectView];

切记testView和蒙版的顺序不要放反了