TianZer

HDN shaders can better denoise, HDN level is from 1 to 3, higher for better denoising but may cause blur and lack of detail.

I wonder your cmake's version and options, I failed to repeat this error with cmake V3.22.0.

I believe this is caused by cmake v3. 20. #88 also got this issue with cmake v3. 20 on windows10. Will figure it out later. For now just uses the...

This error happens at `cmake generate` phase, and it seems you can ignore this error and just use `make` to build.

opencv version?

> opencv-2.4.5-3.el7.src.rpm That's outdated. OpenCV3.2 should be the earliest version which could pass the building. OpenCV4 is recommended.

Well, I did this check inside the code via macros, but to my surprise, opencv2 does not seem to include that version checking macro...

Use the newer version of boost::filesystem library, your current one should be earlier than 1.6. Or upgrade your compiler to which has better c++17 support (gcc8 should be ok, gcc9...

Try using quotes to surround path instead of lots of escaping. This should be a path analyzing issue of opencv.

has your opencv built with ffmpeg module？