图片毛玻璃生成方法
需要导入Accelerate库
*点击项目，找到Build Phases项，在Link Binary With Libraries 里面添加Accelerate.framework
主要通过vImageBoxConvolve_ARGB8888来做模糊处理，
实践表面，通过两次模糊处理，模糊出来的效果更好
#import <Accelerate/Accelerate.h>
- (UIImage *)blurryImage:(UIImage *)image withBlurLevel:(CGFloat)blur {
if (blur < 0.f || blur > 1.f) {
blur = 0.5f;
}
int boxSize = (int)(blur * 100);
boxSize = boxSize - (boxSize % 2) + 1;
CGImageRef img = image.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));
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);
}
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];
//clean up
CGContextRelease(ctx);
CGColorSpaceRelease(colorSpace);
free(pixelBuffer);
CFRelease(inBitmapData);
CGColorSpaceRelease(colorSpace);
CGImageRelease(imageRef);
return returnImage;
}
通过两次模糊处理
//
// ViewController.m
// blurdemo
//
// Created by usteel on 14-4-10.
// Copyright (c) 2014年 nothing. All rights reserved.
//
#import "ViewController.h"
#import <Accelerate/Accelerate.h>
@interface ViewController ()
@end
@implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
UIImageView *vImg = [[UIImageView alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];
UIImage *img = [UIImage imageNamed:@"avatar.jpg"];
img = [self blurryImage:img withBlurLevel:05.f];
vImg.image = img;
[self.view addSubview:vImg];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (UIImage *)blurryImage:(UIImage *)image withBlurLevel:(CGFloat)blur {
if (blur < 0.f || blur > 1.f) {
blur = 0.5f;
}
int boxSize = (int)(blur * 100);
boxSize = boxSize - (boxSize % 2) + 1;
CGImageRef img = image.CGImage;
vImage_Buffer inBuffer, outBuffer, outBuffer2;
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));
if(pixelBuffer == NULL)
NSLog(@"No pixelbuffer");
outBuffer.data = pixelBuffer;
outBuffer.width = CGImageGetWidth(img);
outBuffer.height = CGImageGetHeight(img);
outBuffer.rowBytes = CGImageGetBytesPerRow(img);
outBuffer2.data = pixelBuffer;
outBuffer2.width = CGImageGetWidth(img);
outBuffer2.height = CGImageGetHeight(img);
outBuffer2.rowBytes = CGImageGetBytesPerRow(img);
error = vImageBoxConvolve_ARGB8888(&inBuffer,&outBuffer2,NULL,0,0,boxSize,boxSize,NULL,kvImageEdgeExtend);
error = vImageBoxConvolve_ARGB8888(&outBuffer2,&inBuffer,NULL,0,0,boxSize,boxSize,NULL,kvImageEdgeExtend);
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];
//clean up
CGContextRelease(ctx);
CGColorSpaceRelease(colorSpace);
free(pixelBuffer);
CFRelease(inBitmapData);
CGColorSpaceRelease(colorSpace);
CGImageRelease(imageRef);
return returnImage;
}
@end