GPUImage Blending Mode example

gistfile1.m

- (UIImage*)blendedImage {
    GPUImagePicture* bluredImage = [[GPUImagePicture alloc] initWithImage:self.filterImage];    
    GPUImageFilterGroup* blurFilterGroup = [[GPUImageFilterGroup alloc] init];

    GPUImageFilter* colorOverlayfilter = [[GPUImageFilter alloc] initWithFragmentShaderFromFile:@"WhiteColorOverlay"];
    GPUImageGaussianBlurFilter* gaussainBlur = [[GPUImageGaussianBlurFilter alloc] init];
    [gaussainBlur setBlurSize:3.0f];
    
    [blurFilterGroup addFilter:colorOverlayfilter];
    [blurFilterGroup addFilter:gaussainBlur];
    
    [colorOverlayfilter addTarget:gaussainBlur];
    
    [blurFilterGroup setInitialFilters:[NSArray arrayWithObject:colorOverlayfilter]];
    [blurFilterGroup setTerminalFilter:gaussainBlur];
    
    [bluredImage addTarget:blurFilterGroup];
    [bluredImage processImage];
    GPUImagePicture* bluredImageResult = [[GPUImagePicture alloc] initWithImage:[blurFilterGroup imageFromCurrentlyProcessedOutputWithOrientation:self.filterImage.imageOrientation]];
    
    GPUImageNormalBlendFilter* blendFilter = [[GPUImageNormalBlendFilter alloc] init];
    GPUImagePicture* topImage = [[GPUImagePicture alloc] initWithImage:self.filterImage];
    [bluredImageResult processImage];
    [bluredImageResult addTarget:blendFilter];
    [topImage addTarget:blendFilter];
    [topImage processImage];
    
    return [blendFilter imageFromCurrentlyProcessedOutputWithOrientation:self.filterImage.imageOrientation];
}