ffmpeg: try to load ffmpeg wrapper dll from the current module directory

[alalek]

resolves #6720

[apavlenko]

👍
verified on Win 8.1 x64 and Python 2.7 x64

[techtonik]

Awesome. Is there a way how to test this without compiling everything myself? Nightly builds or something?

[alalek]

@techtonik Currently there are no public artifacts of nightly builds. Also we don't prepare Python .whl packages similar to this

[techtonik]

@alalek I found this - https://github.com/skvark/opencv-python - which is able to produce build artifacts - https://ci.appveyor.com/project/skvark/opencv-python/build/artifacts - is it worthy to propose this for merging?

[alalek]

There artifacts don't include ffmpeg wrapper. But you can built it yourself using command from build scripts.

[techtonik]

Right. But I see it is being copied, so I rebuilt opencv from current HEAD (https://ci.appveyor.com/project/techtonik/opencv-python/build/artifacts), placed opencv_ffmpeg310.dll next to it and it worked! =)