HSV Image Processing

ImageProcessing.cpp

+(int *) processImageWithHsv:(cv::Mat&)rgb_image {
    cv::Mat hsv_image;
    
    cvtColor(rgb_image, hsv_image, CV_RGB2HSV);
    
    // Quanta Ratio
    int scale = 10;
    
    int images_amount = 1;
    int image_channels[] = {0, 1, 2};
    
    int hue_levels = 36, saturation_levels = 25, value_levels = 25;
    int histSize[] = {hue_levels, saturation_levels, value_levels};
    
    float hue_range[] = { 0, 180 };
    float saturation_range[] = { 0, 256 };
    float value_range[] = { 0, 256 };
    
    const float* ranges[] = { hue_range, saturation_range, value_range };
    
    bool clear_at_beggining = false;
    bool uniform_histogram = true;
    int histogram_dimensionality = 3;
    
    cv::MatND histogram;
    
    
    calcHist( &hsv_image,
             images_amount,
             image_channels,
             cv::Mat(),
             histogram,
             histogram_dimensionality,
             histSize,
             ranges,
             uniform_histogram,
             clear_at_beggining );
    
    int maxVal = 0;
    
    int hue = 0;
    int saturation = 0;
    int value = 0;
    
    for (int h = 0; h < hue_levels; h++) {
        for (int s = 0; s < saturation_levels; s++) {
            for (int v = 0; v < value_levels; v++) {
                
                int binVal = histogram.at<int>(h, s, v);
                
                if (binVal > maxVal) {
                    
                    maxVal = binVal;
                    
                    hue = h;
                    saturation = s;
                    value = v;
                }
            }
        }
    }

    hue = hue * scale; // angle 0 - 360
    saturation = saturation * scale; // 0 - 255
    value = value * scale; // 0 - 255
    
    static int  int_hsv_list[3];
    int_hsv_list[0] = hue;
    int_hsv_list[1] = saturation;
    int_hsv_list[2] = value;
    
    cv::Mat3f hsv(cv::Vec3f(hue, saturation, value));
    
    std::cout << "HSV: " << hsv << std::endl;
    
    cv::Mat3f rgb_color;
    cvtColor(hsv, rgb_color, CV_HSV2RGB);
    
    std::cout << "RGB: " << rgb_color << std::endl;
    
    return int_hsv_list;
}