iOS7 设置背景图片或导航为毛玻璃效果
1.首先导入系统库 Accelerate.framework
2.其次在要实现毛玻璃效果的页面添加头文件 #import <Accelerate/Accelerate.h>
3.再次添加实现函数如下：
//加模糊效果函数，传入参数：image是图片，blur是模糊度（0~2.0之间）
- (UIImage *)blurryImage:(UIImage *)image withBlurLevel:(CGFloat)blur
{
//模糊度,
if ((blur < 0.1f) || (blur > 2.0f))
{
blur = 0.5f;
}
//boxSize必须大于0
int boxSize = (int)(blur * 100);
boxSize -= (boxSize % 2) + 1;
NSLog(@"boxSize:%i",boxSize);
//图像处理
CGImageRef img = image.CGImage;
//图像缓存,输入缓存，输出缓存
vImage_Buffer inBuffer, outBuffer;
vImage_Error error;
//像素缓存
void *pixelBuffer;
//数据源提供者，Defines an opaque type that supplies Quartz with data.
CGDataProviderRef inProvider = CGImageGetDataProvider(img);
// provider’s data.
CFDataRef inBitmapData = CGDataProviderCopyData(inProvider);
//宽，高，字节/行，data
inBuffer.width = CGImageGetWidth(img);
inBuffer.height = CGImageGetHeight(img);
inBuffer.rowBytes = CGImageGetBytesPerRow(img);
inBuffer.data = (void*)CFDataGetBytePtr(inBitmapData);
//像数缓存，字节行*图片高
pixelBuffer = malloc(CGImageGetBytesPerRow(img) * CGImageGetHeight(img));
outBuffer.data = pixelBuffer;
outBuffer.width = CGImageGetWidth(img);
outBuffer.height = CGImageGetHeight(img);
outBuffer.rowBytes = CGImageGetBytesPerRow(img);
// 第三个中间的缓存区,抗锯齿的效果
void *pixelBuffer2 = malloc(CGImageGetBytesPerRow(img) * CGImageGetHeight(img));
vImage_Buffer outBuffer2;
outBuffer2.data = pixelBuffer2;
outBuffer2.width = CGImageGetWidth(img);
outBuffer2.height = CGImageGetHeight(img);
outBuffer2.rowBytes = CGImageGetBytesPerRow(img);
//将一个隐式的M×N区域颗粒和具有箱式滤波器的效果的ARGB8888源图像进行卷积运算得到作用区域。
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);
}
// NSLog(@"字节组成部分：%zu",CGImageGetBitsPerComponent(img));
//颜色空间DeviceRGB
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
//用图片创建上下文,CGImageGetBitsPerComponent(img),7,8
CGContextRef ctx = CGBitmapContextCreate(
outBuffer.data,
outBuffer.width,
outBuffer.height,
8,
outBuffer.rowBytes,
colorSpace,
CGImageGetBitmapInfo(image.CGImage));
//根据上下文，处理过的图片，重新组件
CGImageRef imageRef = CGBitmapContextCreateImage (ctx);
UIImage *returnImage = [UIImage imageWithCGImage:imageRef];
//clean up
CGContextRelease(ctx);
CGColorSpaceRelease(colorSpace);
free(pixelBuffer);
free(pixelBuffer2);
CFRelease(inBitmapData);
CGImageRelease(imageRef);
return returnImage;
}
4.使用的时候直接传入所需参数，将返回的image直接运行就可以了UIImage * maoImage = [UIImage imageNamed:@"aboutBackImage.jpg"];;
tabBarImage.image = [self blurryImage:maoImage withBlurLevel:0.5];
大功告成，(*^__^*) ……小伙伴们快去试试效果吧~
转载：http://blog.csdn.net/illusion21/article/details/39054537