Edit - November 10, 2021
The most recent version of the OpenCV docs (4.5.4 at the time of this writing) has the Python signatures directly below the C++ signatures. For your specific case, the function you are interested in can be found here: https://docs.opencv.org/4.5.4/d1/d79/group__photo__denoise.html#ga4c6b0031f56ea3f98f768881279ffe93
Outdated (here for posterity)
OpenCV 3.0 beta docs are the last known stable docs for the Python functions. Unfortunately, anything after they don't show you the equivalent calls between C++ and Python. I use these as a guide, but take them with a grain of salt.
For your specific case: https://docs.opencv.org/3.0-beta/modules/photo/doc/denoising.html?highlight=denoising#fastnlmeansdenoising
Answer from rayryeng on Stack OverflowVideos
» pip install opencv-python
I've used OpenCV for some time now, and I love the functionality it provides, but often I find myself searching through a function documentation only to find parts of its behavior undocumented and I have to experimentally find out how it works, especially when using OpenCV through Python or Java bindings. With every new OpenCV release, more functionality is added to the library while the documentation still lacks on older classes and functions.
I hope I'm the only one with this problem, but I feel there might be others having same issues.
I was wondering if anyone knows a proper reference/documentation for the OpenCV bindings for python (3.x).
If this is not available yet, would it be possible to run a doc generator over the sources? i.e. are they documented properly?