add fast bilateral solver from master

[ytyytyyt]

This pullrequest changes

Adds fixed version of the Fast Bilateral Solver (FBS) from master.

relates #1877

force_builders=linux,docs,windows,macosx

[alalek]

Thank you for the contribution!

Please take a look on build issues here: http://pullrequest.opencv.org/#/summary/contrib

[ytyytyyt]

Thank you for the contribution!

Please take a look on build issues here: http://pullrequest.opencv.org/#/summary/contrib

I will fix the 'Docs' issue (Failed whitespace opencv_contrib).

The warnings are related to unusable variables cause by:

#ifdef HAVE_EIGEN
        //! [filtering_fbs]
        solving_time = (double)getTickCount();        
        fastBilateralSolverFilter(left, left_disp_resized, conf_map/255.0f, solved_disp, fbs_spatial, fbs_luma, fbs_chroma);
        solving_time = ((double)getTickCount() - solving_time)/getTickFrequency();
        //! [filtering_fbs]

        //! [filtering_wls2fbs]
        fastBilateralSolverFilter(left, filtered_disp, conf_map/255.0f, solved_filtered_disp, fbs_spatial, fbs_luma, fbs_chroma);
        //! [filtering_wls2fbs]
#endif

Should I remove the the HAVE_EIGEN or include the unused variables within this block?

One of the failing tests is not related to files I have been adding/modifying, i.e. Failed test_face:
/build/precommit-contrib_linux64/3.4/opencv_contrib/modules/face/test/test_mace.cpp:78: Failure Expected: (self_ok) >= (nSampsTest/2), actual: 0 vs 2

[alalek]

Add #else branch for HAVE_EIGEN:

#else
    (void)fbs_spatial;
    (void)fbs_luma;
    (void)fbs_chroma;
#endif

test_face

Ignore, it is sporadic failure.

[alalek]

Well done! Thank you 👍