iOS 让图片变模糊

#import <Accelerate/Accelerate.h>

1.初始化图片

UIImageView *iv = [[UIImageView alloc]initWithFrame:[UIScreen mainScreen].bounds];

[iv setImage:[self blurryImage:[UIImage imageNamed:@"welcome_2.jpg"] withBlurLevel:0.6]];

[self.view addSubview:iv];

2.让图片变模糊的方法

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

{

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

{

blur = 0.5f;

}

//判断曝光度

int boxSize = (int)(blur * 100);//放大100 小数点后面2位有效

boxSize = boxSize - (boxSize % 2) + 1;//如果是偶数 变奇数

CGImageRef img = image.CGImage;//获取图片指针

vImage_Buffer inBuffer,outBuffer;//获取缓冲区

vImage_Error error;//一个错误类，调用画图函数的时候调用

void *pixelBuffer;

CGDataProviderRef inprovider = CGImageGetDataProvider(img);//放回一个数组图片

CFDataRef inbitmapData = CGDataProviderCopyData(inprovider);//拷贝数据

inBuffer.width = CGImageGetWidth(img);//放回位图的宽度

inBuffer.height = CGImageGetHeight(img);//放回位图的高度

inBuffer.rowBytes = CGImageGetBytesPerRow(img);//算出位图的字节

inBuffer.data = (void*)CFDataGetBytePtr(inbitmapData);//填写图片信息

pixelBuffer = malloc(CGImageGetBytesPerRow(img) * CGImageGetHeight(img));//创建一个空间

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(@"%zd",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];

CGContextRelease(ctx);

CGColorSpaceRelease(colorSpace);

free(pixelBuffer);

CFRelease(inbitmapData);

CGColorSpaceRelease(colorSpace);

CGImageRelease(imageRef);

return returnImage;

}