OpenCV 4.0.0 SystemError: returned a result with an error set

Hello I am trying to create a facial recognition program but I have a peculiar error: here is my code:

import cv2 as cv
gray = cv.cvtColor(img, cv.COLOR_BGR2GRAY)
face_cascade = cv.CascadeClassifier("lbpcascade_frontalface.xml")
faces = face_cascade.detectMultiScale(gray, scaleFactor=1.2, minNeighbors=5);

and this error is the output

SystemError: <class 'cv2.CascadeClassifier'> returned a result with an error set

I have “lbpcascade_frontalface.xml” in the working directory so that shouldn’t be an issue

if it helps when I enter

cv.__version__

I get

'4.0.0'

Answer

New Answer OpenCV seems to now have a directory dedicated to cascades, they are placed in data and I am seeing something like this floating around in tutorials now haar_cascade_face = cv.CascadeClassifier('data/haarcascade/haarcascade_frontalface_default.xml') You may have to find where data is on your machine or the above my work. I have not touched this project since I finished it in early 2019. Bear in mind this only works for frontal face, if you want to use Haar’s Cascade for eyes that is a separate file.

old answer Turns out I didn’t need to download another file and use it because opencv comes with it this little bit of code worked

cv.CascadeClassifier(cv.data.haarcascades + "haarcascade_frontalface_default.xml")