utility.py

import cv2
import numpy as np
 
## TO STACK ALL THE IMAGES IN ONE WINDOW
def stackImages(imgArray, scale, lables=[]):
    rows = len(imgArray)
    cols = len(imgArray[0])
    rowsAvailable = isinstance(imgArray[0], list)
    width = imgArray[0][0].shape[1]
    height = imgArray[0][0].shape[0]

    # Resize and convert to BGR where needed
    if rowsAvailable:
        for x in range(rows):
            for y in range(cols):
                imgArray[x][y] = cv2.resize(imgArray[x][y], (0, 0), None, scale, scale)
                if len(imgArray[x][y].shape) == 2:
                    imgArray[x][y] = cv2.cvtColor(imgArray[x][y], cv2.COLOR_GRAY2BGR)

        imageBlank = np.zeros((height, width, 3), np.uint8)
        hor = [imageBlank] * rows
        for x in range(rows):
            hor[x] = np.hstack(imgArray[x])

        ver = np.vstack(hor)

    else:
        for x in range(rows):
            imgArray[x] = cv2.resize(imgArray[x], (0, 0), None, scale, scale)
            if len(imgArray[x].shape) == 2:
                imgArray[x] = cv2.cvtColor(imgArray[x], cv2.COLOR_GRAY2BGR)

        ver = np.hstack(imgArray)

    # Adding labels
    if len(lables) > 0:
        eachImgWidth = int(ver.shape[1] / cols)
        eachImgHeight = int(ver.shape[0] / rows)
        for d in range(rows):
            for c in range(cols):
                label = lables[d][c] if isinstance(lables[d], list) else lables[d]
                cv2.rectangle(ver, (c * eachImgWidth, eachImgHeight * d), (c * eachImgWidth + len(label) * 13 + 27, 30 + eachImgHeight * d), (255, 255, 255), cv2.FILLED)
                cv2.putText(ver, label, (c * eachImgWidth + 10, eachImgHeight * d + 20), cv2.FONT_HERSHEY_COMPLEX, 0.7, (255, 0, 255), 2)

    return ver
 
def reorder(myPoints):
 
    myPoints = myPoints.reshape((4, 2))
    myPointsNew = np.zeros((4, 1, 2), dtype=np.int32)
    add = myPoints.sum(1)
 
    myPointsNew[0] = myPoints[np.argmin(add)]
    myPointsNew[3] =myPoints[np.argmax(add)]
    diff = np.diff(myPoints, axis=1)
    myPointsNew[1] =myPoints[np.argmin(diff)]
    myPointsNew[2] = myPoints[np.argmax(diff)]
 
    return myPointsNew 
 
def biggestContour(contours):
    biggest = np.array([])
    max_area = 0
    for i in contours:
        area = cv2.contourArea(i)
        if area > 5000:
            peri = cv2.arcLength(i, True)
            approx = cv2.approxPolyDP(i, 0.02 * peri, True)
            if area > max_area and len(approx) == 4:
                biggest = approx
                max_area = area
    return biggest,max_area

def drawRectangle(img,biggest,thickness):
    cv2.line(img, (biggest[0][0][0], biggest[0][0][1]), (biggest[1][0][0], biggest[1][0][1]), (0, 255, 0), thickness)
    cv2.line(img, (biggest[0][0][0], biggest[0][0][1]), (biggest[2][0][0], biggest[2][0][1]), (0, 255, 0), thickness)
    cv2.line(img, (biggest[3][0][0], biggest[3][0][1]), (biggest[2][0][0], biggest[2][0][1]), (0, 255, 0), thickness)
    cv2.line(img, (biggest[3][0][0], biggest[3][0][1]), (biggest[1][0][0], biggest[1][0][1]), (0, 255, 0), thickness)
 
    return img