［IOS 开发代码］UIImage+Blur 网络图片模糊用法

UIImage-Helpers 网络图片模糊用法

    float quality = .00001f;
    float blurred = .5f;

    NSURL *url = [NSURL URLWithString:@"http://pic21.nipic.com/20120614/10230657_130343324168_2.jpg"];

    NSData *data = [[NSData alloc]initWithContentsOfURL:url];

    UIImage *img = [[UIImage alloc]initWithData:data];

    NSData *imageData = UIImageJPEGRepresentation(img, quality);

    userIcon.image = [[UIImage imageWithData:imageData] blurredImage:blurred];

//

//  UIImage+Blur.h

#import <UIKit/UIKit.h>

#import <Accelerate/Accelerate.h>

#import <QuartzCore/QuartzCore.h>

@interface UIImage (Blur)

// 0.0 to 1.0

- (UIImage*)blurredImage:(CGFloat)blurAmount;

@end

//

//  UIImage+Blur.m

#import "UIImage+Blur.h"

@implementation UIImage (Blur)

- (UIImage*)blurredImage:(CGFloat)blurAmount

{

    if (blurAmount < 0.0 || blurAmount > 1.0) {

        blurAmount = 0.5;

    }

    int boxSize = (int)(blurAmount * );

    boxSize = boxSize - (boxSize % ) + ;

    CGImageRef img = self.CGImage;

    vImage_Buffer inBuffer, outBuffer;

    vImage_Error error;

    void *pixelBuffer;

    CGDataProviderRef inProvider = CGImageGetDataProvider(img);

    CFDataRef inBitmapData = 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));

    outBuffer.data = pixelBuffer;

    outBuffer.width = CGImageGetWidth(img);

    outBuffer.height = CGImageGetHeight(img);

    outBuffer.rowBytes = CGImageGetBytesPerRow(img);

    error = vImageBoxConvolve_ARGB8888(&inBuffer, &outBuffer, NULL, , , boxSize, boxSize, NULL, kvImageEdgeExtend);

    if (!error) {

        error = vImageBoxConvolve_ARGB8888(&outBuffer, &inBuffer, NULL, , , boxSize, boxSize, NULL, kvImageEdgeExtend);

    }

    if (error) {

#ifdef DEBUG

        NSLog(@"%s error: %zd", __PRETTY_FUNCTION__, error);

#endif

        return self;

    }

    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();

    CGContextRef ctx = CGBitmapContextCreate(outBuffer.data,

                                             outBuffer.width,

                                             outBuffer.height,

                                             ,

                                             outBuffer.rowBytes,

                                             colorSpace,

                                             (CGBitmapInfo)kCGImageAlphaNoneSkipLast);

    CGImageRef imageRef = CGBitmapContextCreateImage (ctx);

    UIImage *returnImage = [UIImage imageWithCGImage:imageRef];

    CGContextRelease(ctx);

    CGColorSpaceRelease(colorSpace);

    free(pixelBuffer);

    CFRelease(inBitmapData);

    CGImageRelease(imageRef);

    return returnImage;

}

@end