高斯模糊

1.添加Accelerate.Framework

2.调用方法

self.backima.image= [selfblurryImage:self.backima.imagewithBlurLevel:.8f];

3.计算方法

- (UIImage*)blurryImage:(UIImage*)image withBlurLevel:(CGFloat)blur {

if(blur <0.f|| blur >1.f) {

blur =0.5f;

}

intboxSize = (int)(blur *100);

boxSize = boxSize - (boxSize %2) +1;

CGImageRefimg = image.CGImage;

vImage_BufferinBuffer, outBuffer;

vImage_Errorerror;

void*pixelBuffer;

CGDataProviderRefinProvider =CGImageGetDataProvider(img);

CFDataRefinBitmapData =CGDataProviderCopyData(inProvider);

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 ==NULL)

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);

}

CGColorSpaceRefcolorSpace =CGColorSpaceCreateDeviceRGB();

CGContextRefctx =CGBitmapContextCreate(

outBuffer.data,

outBuffer.width,

outBuffer.height,

8,

outBuffer.rowBytes,

colorSpace,

kCGImageAlphaNoneSkipLast);

CGImageRefimageRef =CGBitmapContextCreateImage(ctx);

UIImage*returnImage = [UIImageimageWithCGImage:imageRef];

//clean up

CGContextRelease(ctx);

CGColorSpaceRelease(colorSpace);

free(pixelBuffer);

CFRelease(inBitmapData);

CGColorSpaceRelease(colorSpace);

CGImageRelease(imageRef);

returnreturnImage;

}

摘自:http://blog.csdn.net/ios_che/article/details/12577131