cv2.rectangle TypeError: function takes exactly 4 arguments (2 given)

[augustopozzebon]

• OpenCV => 4.3.0
• Operating System / Platform => Windows 64 Bit
• Compiler => PyCharm

Detailed description

Traceback (most recent call last):
File "PycharmProjects/OpenCV/retangulo_moving.py", line 27, in
frame = cv2.rectangle(frame, (x1, y1), (x1+bw, y1+bh), (0,0,0), -1)
TypeError: function takes exactly 4 arguments (2 given)
[ WARN:0] global C:\projects\opencv-python\opencv\modules\videoio\src\cap_msmf.cpp (436) `anonymous-namespace'::SourceReaderCB::~SourceReaderCB terminating async callback

Steps to reproduce

The error is in the rectangle function. I'm trying to display a moving rectangle in a live video from the WebCam.
When using opencv version 4.0.1 I got the error "an integer is required (got type tuple)". After the update too the 4.3.0 version this new error showed up.

import numpy as np
print(cv2.__version__)


dispW=640
dispH=480
cam=cv2.VideoCapture(0)
cam.set(cv2.CAP_PROP_FPS, 21)
cam.set(cv2.CAP_PROP_FRAME_WIDTH, dispW)
cam.set(cv2.CAP_PROP_FRAME_HEIGHT, dispH)


bw=(.15*dispW)
bh=(.15*dispH)
dx=2
dy=2
x1=10
y1=270


while True:

        ret, frame=cam.read()


        frame = cv2.rectangle(frame, (x1, y1), (x1+bw, y1+bh), (0,0,0), -1)

        cv2.moveWindow('WebCam', 0, 0)
        cv2.imshow('WebCam', frame2)
        x1+=dx
        y1+=dy
        if x1<=0 or x1+bw>=dispW:
            dx=dx*(-1)
        if y1<=0 or y1+bh>=dispH:
            dy=dy*(-1)




        if cv2.waitKey(1)==ord('q'):
            break


cam.release()
cv2.destroyAllWindows()

Issue submission checklist

• I checked the problem with documentation, FAQ, open issues,
  answers.opencv.org, Stack Overflow, etc and have not found solution
• I updated to latest OpenCV version and the issue is still there

[berak]

related: #16432

@algonao, the point coords need to be integer, make it:

bw=int(.15*dispW)
bh=int(.15*dispH)

[augustopozzebon]

Yeah!!! That was it! Thank you berak.