if you meet the fatal error: boostdesc_bgm.i: No such file or directory or fatal error: vgg.i: No such file or directory click here: https://github.com/opencv/opencv_3rdparty/branches/stale enter the "contrib_xfeatures2d_vgg_20160317" and "contrib_xfeatures2d_boostdesc_2" and then download the all ".i" . put the all ".i" in 'opencv_contrib/modules/xfeatures2d/src/' than, make