二维码生成、模糊图片、合成海报

//生成二维码

- (UIImage *)generateQRCodeWithString:(NSString *)string Size:(CGFloat)size
{
    //创建过滤器
    CIFilter *filter = [CIFilter filterWithName:@"CIQRCodeGenerator"];
    //过滤器恢复默认
    [filter setDefaults];
    //给过滤器添加数据<字符串长度893>
    NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding allowLossyConversion:YES];
    [filter setValue:data forKey:@"inputMessage"];
    //获取二维码过滤器生成二维码
    CIImage *image = [filter outputImage];
    UIImage *img = [self createNonInterpolatedUIImageFromCIImage:image WithSize:size];
    return img;
}

//二维码清晰
- (UIImage *)createNonInterpolatedUIImageFromCIImage:(CIImage *)image WithSize:(CGFloat)size
{
    CGRect extent = CGRectIntegral(image.extent);
    CGFloat scale = MIN(size/CGRectGetWidth(extent), size/CGRectGetHeight(extent));
    
    //创建bitmap
    size_t width = CGRectGetWidth(extent)*scale;
    size_t height = CGRectGetHeight(extent)*scale;
    CGColorSpaceRef cs = CGColorSpaceCreateDeviceGray();
    CGContextRef bitmapRef = CGBitmapContextCreate(nil, width, height, 8, 0, cs, (CGBitmapInfo)kCGImageAlphaNone);
    CIContext *context = [CIContext contextWithOptions:nil];
    CGImageRef bitmapImage = [context createCGImage:image fromRect:extent];
    CGContextSetInterpolationQuality(bitmapRef, kCGInterpolationNone);
    CGContextScaleCTM(bitmapRef, scale, scale);
    CGContextDrawImage(bitmapRef, extent, bitmapImage);
    
    //保存图片
    CGImageRef scaledImage = CGBitmapContextCreateImage(bitmapRef);
    CGContextRelease(bitmapRef);
    CGImageRelease(bitmapImage);
    return [UIImage imageWithCGImage:scaledImage];
}

- (void)loadImageFinished:(UIImage *)image
{
    UIImageWriteToSavedPhotosAlbum(image, self, @selector(image:didFinishSavingWithError:contextInfo:), (__bridge void *)self);
}

- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo
{
    [MBProgressHUD showSuccess:@"图片已保存到相册"];
    NSLog(@"image = %@, error = %@, contextInfo = %@", image, error, contextInfo);
}

-(void)loadImage{
//    [self loadImageFinished:[self generateQRCodeWithString:[Config getUserInviteUrl] Size:100]];
    [self combineImge];
}

-(void)copyLink{
    UIPasteboard *pasteboard = [UIPasteboard generalPasteboard];
    pasteboard.string = [Config getUserInviteUrl];
    [MBProgressHUD showSuccess:@"已复制到粘贴板"];
}

- (UIImage *)snapshotImageWithView:(UIView *)view {
    
    UIGraphicsBeginImageContext(view.bounds.size);     //currentView 当前的view  创建一个基于绘图的图形上下文并指定大小为当前视图的bounds
    [view.layer renderInContext:UIGraphicsGetCurrentContext()];//renderInContext呈现接受者及其子范围到指定的上下文
    UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();//返回一个基于当前图形上下文的图片
    UIGraphicsEndImageContext();//移除栈顶的基于当前位图的图形上下文
    return viewImage;
}

- (UIImage *)blurImageWithImage:(UIImage *)image {
    
    CIContext *context = [CIContext contextWithOptions:nil];
    CIImage *inputImage = [[CIImage alloc] initWithImage:image];
    CIFilter *filter = [CIFilter filterWithName:@"CIGaussianBlur"];
    [filter setValue:inputImage forKey:kCIInputImageKey];
    [filter setValue:[NSNumber numberWithFloat:3.0] forKey:@"inputRadius"];
    
    //        CIImage *result = [filter valueForKey:kCIOutputImageKey];
    CIImage *result=[filter outputImage];
    CGImageRef cgImage = [context createCGImage:result fromRect:[inputImage extent]];
    UIImage *img = [UIImage imageWithCGImage:cgImage];
    CGImageRelease(cgImage);
    
    return img;
}

- (void)combineImge {
    UIImage *imgOrigin = [UIImage imageNamed:@"图层 4"];
    UIImage *img = [self blurImageWithImage:imgOrigin];
    
    CGFloat w = [UIScreen mainScreen].bounds.size.width;
    CGFloat h = [UIScreen mainScreen].bounds.size.height;
    
    //以1.png的图大小为底图
    UIImage *img1 = [self snapshotImageWithView:self.qrBGView];
    CGImageRef imgRef1 = img1.CGImage;
    CGFloat w1 = CGImageGetWidth(imgRef1);
    CGFloat h1 = CGImageGetHeight(imgRef1);
    
    //以img 图大小为画布创建上下文
    UIGraphicsBeginImageContext(CGSizeMake(w, h));
    [img drawInRect:CGRectMake(0, 0, w, h)];
    [img1 drawInRect:CGRectMake((w - w1)/2.0, (h - h1)/2.0, w1, h1)];
    UIImage *resultImg = UIGraphicsGetImageFromCurrentImageContext();//从当前上下文中获得最终图片
    UIGraphicsEndImageContext();//关闭上下文
//存储图片
   // UIImageWriteToSavedPhotosAlbum(resultImg, self, @selector(image:didFinishSavingWithError:contextInfo:), (__bridge void *)self);
}