python 3.x - Drawing bounding box on heatmap using cv2

Question

I am working on a project that draws bounding box around the obtained heatmap of the predicted abnormal image in an image classification task. Although, the algorithm I currently have draws a bounding box, it is not ideal. In fact, bounding boxes are quite large than I expect. Here is my code:

            orig_img = (heatmap.permute(1,2,0).cpu().numpy() * 255).astype(np.uint8)
            orig_img = cv2.cvtColor(orig_img, cv2.COLOR_RGB2BGR)
            grey_img = cv2.cvtColor(orig_img, cv2.COLOR_BGR2GRAY)
            thresh = cv2.threshold(grey_img,50, 255, cv2.THRESH_BINARY + cv2.THRESH_OTSU)[1]
            contours = cv2.findContours(thresh, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
            contours = contours[0] if len(contours) == 2 else contours[1]           
            for cnt in contours:
                if len(cnt) > 100:
                    x,y,w,h = cv2.boundingRect(cnt)
                    or_img = (invTrans(inputs[j].cpu()).permute(1,2,0).cpu().numpy() * 255).astype(np.uint8)
                    or_img = cv2.cvtColor(or_img, cv2.COLOR_RGB2BGR)
            cv2.rectangle(or_img, (x,y), (x+w, y+h), (250,0,0),4)
            plt.imshow(or_img)
            cv2.waitKey(0)
            plt.show()

I tried different values for len(cnt) but could not obtain the optimal one. This is an image I got:

This is the image I want:

I would appreciate any help from you, guys.

question from:https://stackoverflow.com/questions/65947690/drawing-bounding-box-on-heatmap-using-cv2

Answer 1

Waitting for answers