NameError: name 'self' is not defined

[hobbyist]

Yes many different .tif where tried.

I changed this line:

self.img = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)

with this line (that seems to work on a code without loading button)

self.img = cv2.imdecode(np.fromfile(frame, dtype=np.uint8), cv2.IMREAD_UNCHANGED)

but I get this error:

Error:
    self.img = cv2.imdecode(np.fromfile(frame, dtype=np.uint8), cv2.IMREAD_UNCHANGED)
AttributeError: 'numpy.ndarray' object has no attribute 'flush'

I am trying with hours of google searching to figure out how to fix it...! Any ideas?

update: Ok, I will take a look. Thanks!!
(I posted the question and then I saw your last post with OrthoViewLite).