Jetson Nano and OpenCV: Color Fetcher

Soo here I’ve made a project in which you can click on any point on the camera display screen and obtain the exact proportions of BGR (blue, green, red) at that point/pixel.

Demo:

Things Required:

1. Jetson Nano
2. Keyboard
3. Mouse
4. HDMI Screen
5. Raspberry Pi Camera
6. External Power Supply

Reference Material:

1. Video that I followed for this project: (LINK)

Code:

Note that code below is in python

View on/Download from Github: (LINK)

import cv2 
import numpy as np 

evt=-1
coord=[]
img=np.zeros((250,250,3),np.uint8)

def click (event, x,y,flags, params):
    global pnt 
    global evt
    if event == cv2.EVENT_LBUTTONDOWN:
        print('Mouse event was: ', event)
        pnt=(x,y)
        coord.append(pnt)
        #print(coord)
        evt=event
    if event == cv2.EVENT_RBUTTONDOWN:
        print(x,y)
        blue=frame[y,x,0]
        green=frame[y,x,1]
        red= frame[y,x,2]
        print(blue,green,red)
        colorString= str(blue)+','+str(green)+','+str(red)
        img[:]=[blue,green,red]
        fnt= cv2.FONT_HERSHEY_PLAIN
        r=255-int(red)
        g=255-int(green)
        b=255-int(blue)
        tp=(b,g,r)
        cv2.putText(img, colorString, (10,25), fnt, 1, tp, 2)
        cv2.imshow('color',img)

dispW=640
dispH=480
flip=2
cv2.namedWindow('nanoCam')
cv2.setMouseCallback('nanoCam', click)
camSet='nvarguscamerasrc !  video/x-raw(memory:NVMM), width=3264, height=2464, format=NV12, framerate=21/1 ! nvvidconv flip-method='+str(flip)+' ! video/x-raw, width='+str(dispW)+', height='+str(dispH)+', format=BGRx ! videoconvert ! video/x-raw, format=BGR ! appsink'
cam= cv2.VideoCapture(camSet)
while True:
    ret, frame= cam.read()
    for pnts in coord:
        cv2.circle(frame, pnts, 5, (0,0,255),-1)
        font= cv2.FONT_HERSHEY_PLAIN
        myStr= str(pnts)
        cv2.putText(frame, myStr, pnts, font, 1,(255,0,0),2)
    cv2.imshow('nanoCam', frame)
    keyEvent= cv2.waitKey(1)
    if keyEvent == ord('q'):
        break
    if keyEvent == ord('c'):
        coord=[]
cam.release()
cv2.destroyAllWindows()

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