cvzone PoseDetector: Python OpenCV and mediapipe - ValueError: too many values to unpack

Question

I'm trying to run the cvzone gesturedetection.py code using OpenCV (version 4.4.0.4). When I run the code, I see my webcam image for 2 seconds and then it closes immediately. I then get an error stating that there are issues with capturing the landmark data. Is it a code error, or are the packages incompatible? I'm running the following code:

from cvzone.PoseModule import PoseDetector
import cv2

detector = PoseDetector()#upBody=True
cap = cv2.VideoCapture(0)

while True:
    _, img = cap.read()

    img = detector.findPose(img, draw=False)
    lmList, bboxInfo = detector.findPosition(img, draw=False)

    gesture = ''
    if bboxInfo:
        angArmL = detector.findAngle(img, 13, 11, 23, draw=False)
        angArmR = detector.findAngle(img, 14, 12, 24, draw=False)
        crossDistL, img, _ = detector.findDistance(15, 12, img)
        crossDistR, img, _ = detector.findDistance(16, 11, img)

        if detector.angleCheck(angArmL, 90) and detector.angleCheck(angArmR, 270):
            gesture = 'T Pose'
        elif detector.angleCheck(angArmL, 170) and detector.angleCheck(angArmR, 180):
            gesture = 'UP'
        elif crossDistL:
            if crossDistL < 70 and crossDistR < 70:
                gesture = "Cross"

        cv2.putText(img, gesture, (20, 50), cv2.FONT_HERSHEY_PLAIN, 3, (255, 0, 255), 3)

    cv2.imshow("Image", img)
    cv2.waitKey(1)

I get the following error:

Traceback (most recent call last):
  File "Part2/GestureDetection.py", line 15, in <module>
    angArmL = detector.findAngle(img, 13, 11, 23, draw=False)
  File ".../cvzone/PoseModule.py", line 98, in findAngle
    x1, y1 = self.lmList[p1][1:]

The code for the findAngle is

    def findAngle(self, img, p1, p2, p3, draw=True):
        """
        Finds angle between three points. Inputs index values of landmarks
        instead of the actual points.
        :param img: Image to draw output on.
        :param p1: Point1 - Index of Landmark 1.
        :param p2: Point2 - Index of Landmark 2.
        :param p3: Point3 - Index of Landmark 3.
        :param draw:  Flag to draw the output on the image.
        :return:
        """

        # Get the landmarks
        x1, y1 = self.lmList[p1][1:]
        x2, y2 = self.lmList[p2][1:]
        x3, y3 = self.lmList[p3][1:]

        # Calculate the Angle
        angle = math.degrees(math.atan2(y3 - y2, x3 - x2) -
                             math.atan2(y1 - y2, x1 - x2))
        if angle < 0:
            angle += 360

        # Draw
        if draw:
            cv2.line(img, (x1, y1), (x2, y2), (255, 255, 255), 3)
            cv2.line(img, (x3, y3), (x2, y2), (255, 255, 255), 3)
            cv2.circle(img, (x1, y1), 10, (0, 0, 255), cv2.FILLED)
            cv2.circle(img, (x1, y1), 15, (0, 0, 255), 2)
            cv2.circle(img, (x2, y2), 10, (0, 0, 255), cv2.FILLED)
            cv2.circle(img, (x2, y2), 15, (0, 0, 255), 2)
            cv2.circle(img, (x3, y3), 10, (0, 0, 255), cv2.FILLED)
            cv2.circle(img, (x3, y3), 15, (0, 0, 255), 2)
            cv2.putText(img, str(int(angle)), (x2 - 50, y2 + 50),
                        cv2.FONT_HERSHEY_PLAIN, 2, (0, 0, 255), 2)
        return angle

Answer 1

I see that lmlist was returning 4 values rather than the expected 3 values in the original code. To reduce the number of values, I specified the number of landmark values for x1,y1, by doing this:

#original:
x1, y1 = self.lmList[p1][1]

#change:
x1, y1 = self.lmList[p1][1:3]

Here are the changes I made to the following two functions in PoseModule.py

    def findAngle(self, img, p1, p2, p3, draw=True):
        """
        Finds angle between three points. Inputs index values of landmarks
        instead of the actual points.
        :param img: Image to draw output on.
        :param p1: Point1 - Index of Landmark 1.
        :param p2: Point2 - Index of Landmark 2.
        :param p3: Point3 - Index of Landmark 3.
        :param draw:  Flag to draw the output on the image.
        :return:
        """

        # Get the landmarks
        x1, y1 = self.lmList[p1][1:3]
        x2, y2 = self.lmList[p2][1:3]
        x3, y3 = self.lmList[p3][1:3]

        # Calculate the Angle
        angle = math.degrees(math.atan2(y3 - y2, x3 - x2) -
                             math.atan2(y1 - y2, x1 - x2))
        if angle < 0:
            angle += 360

        # Draw
        if draw:
            cv2.line(img, (x1, y1), (x2, y2), (255, 255, 255), 3)
            cv2.line(img, (x3, y3), (x2, y2), (255, 255, 255), 3)
            cv2.circle(img, (x1, y1), 10, (0, 0, 255), cv2.FILLED)
            cv2.circle(img, (x1, y1), 15, (0, 0, 255), 2)
            cv2.circle(img, (x2, y2), 10, (0, 0, 255), cv2.FILLED)
            cv2.circle(img, (x2, y2), 15, (0, 0, 255), 2)
            cv2.circle(img, (x3, y3), 10, (0, 0, 255), cv2.FILLED)
            cv2.circle(img, (x3, y3), 15, (0, 0, 255), 2)
            cv2.putText(img, str(int(angle)), (x2 - 50, y2 + 50),
                        cv2.FONT_HERSHEY_PLAIN, 2, (0, 0, 255), 2)
        return angle

    def findDistance(self, p1, p2, img, draw=True, r=15, t=3):
        x1, y1 = self.lmList[p1][1:3]
        x2, y2 = self.lmList[p2][1:3]
        cx, cy = (x1 + x2) // 2, (y1 + y2) // 2

        if draw:
            cv2.line(img, (x1, y1), (x2, y2), (255, 0, 255), t)
            cv2.circle(img, (x1, y1), r, (255, 0, 255), cv2.FILLED)
            cv2.circle(img, (x2, y2), r, (255, 0, 255), cv2.FILLED)
            cv2.circle(img, (cx, cy), r, (0, 0, 255), cv2.FILLED)
        length = math.hypot(x2 - x1, y2 - y1)

        return length, img, [x1, y1, x2, y2, cx, cy]