Issue #2837

[LaurentBerger]

solved #2837

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

• [x] I agree to contribute to the project under Apache 2 License.
• [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or other license that is incompatible with OpenCV
• [x] The PR is proposed to proper branch
• [x] There is reference to original bug report and related work
• [ ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable Patch to opencv_extra has the same branch name.
• [x] The feature is well documented and sample code can be built with the project CMake

[LaurentBerger]

@alalek it's not ready

[asenyaev]

jenkins cn please retry a build