图片打马赛克

#pragma mark - 马赛克
- (UIImage *)Mosaic:(UIImage *)inImage Level:(int)level
{
    unsigned char *imgPixel = RequestImagePixelData(inImage);
    CGImageRef inImageRef = [inImage CGImage];
    GLuint width = CGImageGetWidth(inImageRef);
    GLuint height = CGImageGetHeight(inImageRef);
    unsigned char prev[4] = {0};
    int bytewidth = width*4;
    int i,j;
    int val = level;
    for(i=0;i<height;i++) {
        if (((i+1)%val) == 0) {
            memcpy(imgPixel+bytewidth*i, imgPixel+bytewidth*(i-1), bytewidth);
            continue;
        }
        for(j=0;j<width;j++) {
            if (((j+1)%val) == 1) {
                memcpy(prev, imgPixel+bytewidth*i+j*4, 4);
                continue;
            }
            memcpy(imgPixel+bytewidth*i+j*4, prev, 4);
        }
    }
    NSInteger dataLength = width*height* 4;
    //下面的代码创建要输出的图像的相关参数
    CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, imgPixel, dataLength, NULL);
    // prep the ingredients
    int bitsPerComponent = 8;
    int bitsPerPixel = 32;
    CGColorSpaceRef colorSpaceRef = CGColorSpaceCreateDeviceRGB();
    CGBitmapInfo bitmapInfo = kCGBitmapByteOrderDefault;
    CGColorRenderingIntent renderingIntent = kCGRenderingIntentDefault;
    //创建要输出的图像
    CGImageRef imageRef = CGImageCreate(width, height,
                                        bitsPerComponent,
                                        bitsPerPixel,
                                        bytewidth,
                                        colorSpaceRef,
                                        bitmapInfo,
                                        provider,
                                        NULL, NO, renderingIntent);
    UIImage *my_Image = [UIImage imageWithCGImage:imageRef];
    CFRelease(imageRef);
    CGColorSpaceRelease(colorSpaceRef);
    CGDataProviderRelease(provider);
    return my_Image;
}