OpenCV — is a library of programming functions mainly for real-time computer vision. 
In this article, let`s create a window that will contain an RGB color palette with track stripes. By moving the trackbars, the RGB Colors value will change from 0 to 255. So using the same we can find a color with its RGB values.

  Libraries needed:  OpenCV Numpy  

  Fit:  
 Create a black window with three color channels at 512 x 512 resolution. Then create three trackbars & # 39; B & # 39; & # 39; G & # 39; & # 39; R & # 39; using the predefined functions of the OpenCV library. Set channel values ​​from 0 to 255. Merges a black box with these colored trackbars. 

  




  # Python program for creating RGB color  
  # palette with trackbars  
  
  # import libraries 
  import   cv2 
  import   numpy as np 
   
  # empty function is called when  
  # any trackbar movement  
  def   emptyFunction (): 
   pass  
  
  def   main (): 
   
   # black window with 3 color channels  
   image   =   np.zeros ((  512  ,   512  ,   3  ), np.uint8) 
   windowName   =   "Open CV Color Palette"  
  
   # window name   
   cv2.namedWindow (windowName) 
  
    # there are trackbars named  
   Number of trackbars min. and max. values ​​ 
   cv2.createTrackbar (  ` Blue`  , windowName,   0  ,   255  , emptyFunction) 
   cv2.createTrackbar ( ` Green`  , windowName,   0  ,   255  , emptyFunction)  
   cv2.createTrackbar (  `Red`  , windowName,   0  ,   255  , emptyFunction) 
  
    # Used to open the window  

   # before clicking ESC keys  
   while   (  True  ): 
   cv2.imshow (windowName, image) 
  
   if   cv2.waitKey (  1  )   =   =   27  : 

   break   
  
   # blue values , green , red  
   blue   =   cv2.getTrackbarPos (  `Blue`  , windowName)   
   green   =   cv2.getTrackbarPos ( ` Green`  , windowName) 
   red   =   cv2.getTrackbarPos (  `Red`  , windowName) 
   
   # combine all three color channels and  
   # make the image a composite image from rgb  
 < p>   image [:]   =   [blue, green, red] 
    print   (blue, green, red) 
  
    cv2.destroyAllWindows () 
  
  # Call main ()  
  if   __ name__   =   =   "__ main__"  :  
   main () 



  
  Exit: