#installing lib
import cv2
import numpy as np


# Draw rectangle based on the input selection
def draw_rectangle(event, x, y, flags, params):
    global x_init, y_init, drawing, top_left_pt, bottom_right_pt,image_orig
    
   

    # Detecting mouse button down event
    if event == cv2.EVENT_LBUTTONDOWN:
        drawing = True
        x_init, y_init = x, y
       
    
    
    # Detecting mouse movement
    elif event == cv2.EVENT_MOUSEMOVE:
        if drawing:
            top_left_pt, bottom_right_pt = (x_init,y_init), (x,y)
            image[y_init:y, x_init:x] = 255 - image_orig[y_init:y,
            x_init:x]
            cv2.rectangle(image, top_left_pt, bottom_right_pt,
            (0,255,0), 2)
           
        # Detecting mouse button up event
    elif event == cv2.EVENT_LBUTTONUP:
        drawing = False
        top_left_pt, bottom_right_pt = (x_init,y_init), (x,y)
        image[y_init:y, x_init:x] = 255 - image[y_init:y, x_init:x]
        cv2.rectangle(image, top_left_pt, bottom_right_pt,
        (0,255,0), 2)
        rect_final = (x_init, y_init, x-x_init, y-y_init)
        
        # Runing Grabcut on the region of interest
        run_grabcut(image_orig, rect_final)
        
        # applying Grabcut algorithm
def run_grabcut(image_orig, rect_final):
    
# Initializing the mask
    mask = np.zeros(image_orig.shape[:2],np.uint8)
    # Extract the rectangle and set the region of
    # interest in the above mask
    x,y,w,h = rect_final

    mask[y:y+h, x:x+w] = 1
    # Initialize background and foreground models
    bgdModel = np.zeros((1,65), np.float64)
    fgdModel = np.zeros((1,65), np.float64)
    # Run Grabcut algorithm
    cv2.grabCut(image_orig, mask, rect_final, bgdModel, fgdModel, 5,
    cv2.GC_INIT_WITH_RECT)
    
   # Extracting new mask
    mask2 = np.where((mask==2)|(mask==0),0,1).astype('uint8')
    # Apply the above mask to the image
    image_orig = image_orig*mask2[:,:,np.newaxis]
    
    # Displaying the image
    cv2.imshow('Output', image_orig)
if __name__=='__main__':
    drawing = False
    top_left_pt, bottom_right_pt = (-1,-1), (-1,-1)
    # Read the input image
    image_orig = cv2.imread("vaulted.jpg")
    image_orig = cv2.resize( image_orig ,(500,500))
    image = image_orig.copy()
    cv2.namedWindow('Input')
    cv2.setMouseCallback('Input', draw_rectangle)
    while True:
        cv2.imshow('Input', image)
        c = cv2.waitKey(1)
        if c == 27:
            break
            #clearing ram memory
    cv2.destroyAllWindows()