Bounding boxes around certain colors

edit

If you add an image it'll be more clear. I have only a C++ code to detect colors and draw bounding box search in the internet and you will find a lot of codes with Python doing the same job.

    //===================== code ====================
     if you want to detect yellow  blocks you can test this :
//Convert your image to HSV
cvtColor(im, imHSV, COLOR_BGR2HSV);
//Select yellow part of the image
inRange(imHSV, Scalar(0, 208, 186), Scalar(47, 255, 255), mask1);
//Detect the contours of the yellow parts
vector<vector<Point>> contours; // Vector for storing contours
vector<Point> Ncontours;
 // Find the contours in the image
findContours(mask1, contours, RETR_CCOMP, CHAIN_APPROX_SIMPLE); 

for (size_t i = 0; i < contours.size(); i++) // iterate through each contour.
{
    double area = contourArea(contours[i]);  //  Find the area of contour

    if (area > largest_area)
    {
        largest_area = area;
            //Store the index of largest contour
        largest_contour_index = i;
             // Find the bounding rectangle for biggest contour               
        bounding_rect = boundingRect(contours[i]);
        Ncontours = contours[i];
    }
}

//In this code i serch the largest_area you can modifie the code to get all the contours present in you code