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Project Idea (Augmented Reality – QR Code Scanner)
  • Last Updated : 06 Feb, 2018
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Project Idea : A project based on scanning and detecting qr codes and with inclusion of pose estimation for optimization in detection of qr code and displaying a pyramid over it virtually and storing the read data from qr code.

QR Code – Quick Response code -A QR code uses four standardized encoding modes (numeric, alphanumeric and byte/binary) to efficiently store data; extensions may also be used.

How to install
->Install python (2.7 or 3.0 or higher)
->Install OpenCV Library for Ubuntu
->Install zbar, numpy, PIL Libraries for ubuntu
->Copy and paste the code in the editor and save it as

Running the code :
->Open terminal and run the following command

import zbar
from PIL import Image,ImageColor
import cv2
import numpy as np
cv2.namedWindow("Python Qr-Code Detection")
cap = cv2.VideoCapture(0)
scanner = zbar.ImageScanner()
while True:
        ret, im =
        if not ret:
    # Read Image
    #im = cv2.imread("sahilkhosla.jpg");
    size = im.shape
    gray = cv2.cvtColor(im, cv2.COLOR_BGR2GRAY, dstCn=0)
        pil = Image.fromarray(gray)
        width, height = pil.size
        raw = pil.tobytes()
        image = zbar.Image(width, height, 'Y800', raw)
    for symbol in image:
            print 'decoded', symbol.type, 'symbol', '"%s"' %
        topLeftCorners, bottomLeftCorners, bottomRightCorners, topRightCorners = [item for item in symbol.location]
            cv2.line(im, topLeftCorners, topRightCorners, (255,0,0),2)
                cv2.line(im, topLeftCorners, bottomLeftCorners, (255,0,0),2)
            cv2.line(im, topRightCorners, bottomRightCorners, (255,0,0),2)
            cv2.line(im, bottomLeftCorners, bottomRightCorners, (255,0,0),2)
        #2D image points. If you change the image, you need to change vector
        image_points = np.array([
                            (int((topLeftCorners[0]+topRightCorners[0])/2), int((topLeftCorners[1]+bottomLeftCorners[1])/2)),     # Nose
                            topLeftCorners,     # Left eye left corner
                            topRightCorners,     # Right eye right corne
                            bottomLeftCorners,     # Left Mouth corner
                            bottomRightCorners      # Right mouth corner
                        ], dtype="double")
        # 3D model points.
        model_points = np.array([
                            (0.0, 0.0, 0.0),             # Nose
                            (-225.0, 170.0, -135.0),     # Left eye left corner
                            (225.0, 170.0, -135.0),      # Right eye right corne
                            (-150.0, -150.0, -125.0),    # Left Mouth corner
                            (150.0, -150.0, -125.0)      # Right mouth corner
        # Camera internals
        focal_length = size[1]
        center = (size[1]/2, size[0]/2)
        camera_matrix = np.array(
                         [[focal_length, 0, center[0]],
                         [0, focal_length, center[1]],
                         [0, 0, 1]], dtype = "double"
        print "Camera Matrix :\n {0}".format(camera_matrix)
        dist_coeffs = np.zeros((4,1)) # Assuming no lens distortion
        (success, rotation_vector, translation_vector) = cv2.solvePnP(model_points, image_points, camera_matrix, dist_coeffs, flags=cv2.CV_ITERATIVE)
        print "Rotation Vector:\n {0}".format(rotation_vector)
        print "Translation Vector:\n {0}".format(translation_vector)
        # Project a 3D point (0, 0, 1000.0) onto the image plane.
        # We use this to draw a line sticking out of the nose
        (nose_end_point2D, jacobian) = cv2.projectPoints(np.array([(0.0, 0.0, 100.0)]), rotation_vector, translation_vector, camera_matrix, dist_coeffs)
        for p in image_points:
  , (int(p[0]), int(p[1])), 3, (0,0,255), -1)
        p1 = ( int(image_points[0][0]), int(image_points[0][1]))
        p2 = ( int(nose_end_point2D[0][0][0]), int(nose_end_point2D[0][0][1]))
        cv2.line(im, bottomLeftCorners, p2, (255,0,0), 2)
        cv2.line(im, topLeftCorners, p2, (255,0,0), 2)
        cv2.line(im, bottomRightCorners, p2, (255,0,0), 2)
        cv2.line(im, topRightCorners, p2, (255,0,0), 2)
        # Display image
    cv2.imshow("Output", im)
    # Wait for the magic key
        keypress = cv2.waitKey(1) & 0xFF
        if keypress == ord('q'):

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