Fix findTransformECC error

[songheony]

In some OpenCV library, it is needed to input parameter inputMask and gaussFiltSize for findTransformECC.
I've fixed it following this comment.
And, from official OpenCV Github and the document site, I've set gaussFiltSize as 5.

[timmeinhardt]

Thank you for your PR but which bug are you referring to? Running the camera compensation works in the current master branch.

[songheony]

I'm using master branch, and I installed openCV from Anaconda by the following command
conda install -c conda-forge opencv
I think this is due to differences in the environment where the openCV was built.

[timmeinhardt]

Okay, but I want to keep the repository working with the instructions given in the README.md. So your changes might not work with the OpenCV version recommended in the README.md. I will keep the PR open just in case someone struggles with the same issues but at this point I will not merge it into the main branch.

[songheony]

I fully agree with your decision. And that's why I used try-except.
People using the proposed version of OpenCV will not get an error with the original code, so the code below (after except) will not be executed.
Anyway, I just want people suffering from issues like me to see this PR and fix the code.

[timmeinhardt]

I think your issue comes from installing a different opencv version than used in the master branch. Have you tried installing it they way you did but specifying the same version as in our requirements.txt?