OpenCV TypeError: Expected cv::UMat for argument 'src' - What is this?

Disclaimer: huge openCV noob

Traceback (most recent call last):

File "lanes2.py", line 22, in

canny = canny(lane_image)

File "lanes2.py", line 5, in canny

gray = cv2.cvtColor(imgUMat, cv2.COLOR_RGB2GRAY)

TypeError: Expected cv::UMat for argument 'src'

What exactly is 'src' referring to?

src is the first argument to cv2.cvtColor.

The error you are getting is because it is not the right form. cv2.Umat() is functionally equivalent to np.float32(), so your last line of code should read:

gray = cv2.cvtColor(np.float32(imgUMat), cv2.COLOR_RGB2GRAY)

gray = cv2.cvtColor(cv2.UMat(imgUMat), cv2.COLOR_RGB2GRAY)

UMat is a part of the Transparent API (TAPI) than help to write one code for the CPU and OpenCL implementations.

The following can be used from numpy:

import numpy as np 
image = np.array(image)

Not your code is the problem this is perfectly fine:

gray = cv2.cvtColor(imgUMat, cv2.COLOR_RGB2GRAY)

The problem is that imgUMat is None so you probably made a mistake when loading your image:

imgUMat = cv2.imread("your_image.jpg")

I suspect you just entered the wrong image path.

Just add this at start:

image = cv2.imread(image)