System information (version)

• OpenCV => 3.0.0-dev (master)
• Operating System / Platform => Windows Phone 8.1
• Compiler => Visual Studio 2013

Detailed description

Stitcher.stitch() function works pretty fine on Windows Phone emulators (x86 code, checked both WP8.1 and W10M) but fails on the real device (I used Microsoft Lumia 950 for development). From my code trace, I found that call of matcher->knnMatch(features1.descriptors, features2.descriptors, pair_matches, 2); in the matchers.cpp produces different pair_matches on emulator and real handset. Sorry, I can't trace this sophisticated code too deep.

I'm using this picture set; for the test app, I've modified slightly (for simplicity) opencv_perf_stitching project by this way (added these lines at the beginning:

    Mat pano;
    vector<Mat> imgs;
    imgs.push_back( imread( "1.jpg" ) );
    imgs.push_back( imread( "2.jpg" ) );
    imgs.push_back( imread( "3.jpg" ) );

   Stitcher stitcher = Stitcher::createDefault();
   auto result = stitcher.stitch(imgs, pano);

Could you please fix this issue as soon as you can (or suggest workaround)? It's a real showstopper for me now :(

Steps to reproduce

• download and unzip this picture set
• open solution OpenCV.sln
• set active project opencv_perf_stitching
• modify source file perf_stitch.cpp as described above
• add images 1.jpg, 2.jpg, 3.jpg as a Content to the project
• build project on x86 platform and run on emulator, status will be 0 (normal situation, panorama built)
• build project on arm platform and run on real phone, status will be 1, i.e. ERR_NEED_MORE_IMGS (matcher not found points)