CV2 Image Memory

Question

I have a function to draw rectangles on an image. The input image is always the same but after I run the function to draw and plot the image with contours if I run it again, it keeps the old contour. The original image is read at the beginning of the function every time so I don't understand why it doesn't initialize it as if no contour were drawn previously.

I'm new to python and opencv . Please let me know if you have any suggestion to clear the image before applying contours again

def get_last_col(date_headers):

    n_tables = len(date_headers)
    
    print(n_tables)
   
    image=date_headers[0][0]

    
    for header in date_headers:
        
        h_d = header[1]
        
        page_h = image.shape[0]

        last_col = h_d[h_d.bloc_x==max(h_d.bloc_x)]

        last_col['width'] = last_col.bloc_xw - last_col.bloc_x

        min_w = int(min(last_col.width))

        # X of most bottom left corner date in header
        bottom_left = min( int(min(last_col['bloc_x'])-50), int(min(last_col['bloc_x'])-min_w) )

        # Y of of most bottom date element
        bottom_top = int(last_col.Y_DATE)-20

        #X of most bottom right corner date in header
        bottom_right = int(max(h_d['bloc_xw'])+min_w)-10
        
        
        cv2.rectangle(image, (bottom_left,bottom_top), (bottom_right,page_h), (36,255,12), 2)

    plt.figure(figsize = (30,30))
    plt.imshow(image)

Examples after running the function once and then once again with a different contour

first run

second run

Answer 1

我通过使用图像的副本 (date_headers[0][0].copy()) 弄清楚了