QR_Code_Detection in Python

QR_Code_Detection_Python.py

# Import the necessary packages
from pyzbar import pyzbar
import cv2
#--------------------------------------------------------------------------------------------------------#
def initCamera(camera_id, frame_width, frame_height):                          #Function to initialize the CV videocapture.
    
    print('==> Trying to initialize the camera...')
    cap = cv2.VideoCapture( int(camera_id) )                                   #Start VideoCapture with the appropriate camera ID.  
     
    if not cap.isOpened():                                                     #Test if the stream is opened.
        print("ERROR: Cannot open camera")
        exit()                                                                 #Exit Python.
                
    cap.set(3, int(frame_width))                                               #Cap set (ID, Number we want) . 3 is the ID for Width.
    cap.set(4, int(frame_height))                                              #Cap set (ID, Number we want) . 4 is the ID for Height.
    #cap.set(5, int(15))                                                       #5 is the ID for Framerate.
    
    #print ( cap.get(3) )
    #print ( cap.get(4) )
    #print ( cap.get(5) )
    print('Camera is successfully initialized')
    return cap
#--------------------------------------------------------------------------------------------------------#
print("[INFO] starting video stream...")              
#found = set()                                                                  #Initialize the set of barcodes found thus far. 

cap = initCamera(0, 500, 500)

while True:                                                                    #Loop over the frames from the video stream.
    ret, frame = cap.read()                                                    #Capture a frame. Returning a BOOL and the Frame.        
    if not ret:                                                                #ret = True if the frame is read correctly.                  
        print("Can't receive frame. Exiting ...")
        break                                                                  #Break the stream if a Frame is not read correctly.
    frame    = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)                         #Convert the image to grayscale.
    barcodes = pyzbar.decode (frame)                                           #Find the barcodes in the frame and decode each of the barcodes.
    
    for barcode in barcodes:                                                   #Loop over the detected barcodes.
		
            (x, y, w, h) = barcode.rect                                        #Extract the bounding box location of the barcode.
            cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 0, 255), 2)       #Draw the box surrounding the barcode on the image.
            barcodeData = barcode.data.decode("utf-8")                         #Convert the byte object (barcode.data) to string.
            barcodeType = barcode.type                                         #Get the type of the barcode used.
            text = "{} ({})".format(barcodeData, barcodeType)                  #Set the text parameter to be drawn in the frame.
            cv2.putText(frame, text, (x, y - 10), cv2.FONT_HERSHEY_SIMPLEX, 0.5, (0, 0, 255), 2)  #Draw the barcode data and barcode type on the image.

    #if barcodeData not in found and False:                                    #If the barcode is not in CSV file.
    #    csv.write("{},{}\n".format(datetime.datetime.now(),	barcodeData))    #Write the timestamp + barcode.
    #    csv.flush()
    #    found.add(barcodeData)                                                #Update the set.
            
    cv2.imshow("Barcode Scanner", frame)                                       #Show the output frame.
    if cv2.waitKey(1) & 0xFF == ord('q'):                                      #If the `q` key was pressed, break from the loop.
        break
    
print("[INFO] cleaning up...")                                                 
#csv.close()                                                                   #Close the output CSV file do a bit of cleanup.
cv2.destroyAllWindows()
print("[INFO] Closed") 

qr_code_python_libraries.txt

pyzbar 0.1.8 
https://pypi.org/project/pyzbar/

PyQRCode 1.2.1 
https://pypi.org/project/PyQRCode/

An OpenCV barcode and QR code scanner with ZBar
https://www.pyimagesearch.com/2018/05/21/an-opencv-barcode-and-qr-code-scanner-with-zbar/