1 /**
2 * 模糊背景
3 *
4 * @param image 需要模糊的图片
5 * @param blur 高斯模糊的值
6 *
7 * @return
8 */
9 - (UIImage *)blurryImage:(UIImage *)image withBlurLevel:(CGFloat)blur
10 {
11 if ((blur < 0.0f) || (blur > 1.0f)) {
12 blur = 0.5f;
13 }
14
15 int boxSize = (int)(blur * 100);
16 boxSize -= (boxSize % 2) + 1;
17
18 CGImageRef img = image.CGImage;
19
20 vImage_Buffer inBuffer, outBuffer;
21 vImage_Error error;
22 void *pixelBuffer;
23
24 CGDataProviderRef inProvider = CGImageGetDataProvider(img);
25 CFDataRef inBitmapData = CGDataProviderCopyData(inProvider);
26
27 inBuffer.width = CGImageGetWidth(img);
28 inBuffer.height = CGImageGetHeight(img);
29 inBuffer.rowBytes = CGImageGetBytesPerRow(img);
30 inBuffer.data = (void*)CFDataGetBytePtr(inBitmapData);
31
32 pixelBuffer = malloc(CGImageGetBytesPerRow(img) * CGImageGetHeight(img));
33
34 outBuffer.data = pixelBuffer;
35 outBuffer.width = CGImageGetWidth(img);
36 outBuffer.height = CGImageGetHeight(img);
37 outBuffer.rowBytes = CGImageGetBytesPerRow(img);
38
39 error = vImageBoxConvolve_ARGB8888(&inBuffer, &outBuffer, NULL, 0, 0, boxSize, boxSize, NULL, kvImageEdgeExtend);
40
41 CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
42 CGContextRef ctx = CGBitmapContextCreate(outBuffer.data, outBuffer.width, outBuffer.height, 8, outBuffer.rowBytes, colorSpace, CGImageGetBitmapInfo(image.CGImage));
43
44 CGImageRef imageRef = CGBitmapContextCreateImage (ctx);
45 UIImage *returnImage = [UIImage imageWithCGImage:imageRef];
46
47 //clean up
48 CGContextRelease(ctx);
49 CGColorSpaceRelease(colorSpace);
50
51 free(pixelBuffer);
52 CFRelease(inBitmapData);
53
54 CGColorSpaceRelease(colorSpace);
55 CGImageRelease(imageRef);
56
57 return returnImage;
58 }
