Fast Library for Approximate Nearest Neighbors

lastmod 2018-08-17created 2017-11-065 edits

Troubleshooting

=== Unsupported format or combination of formats (type=0) ===

• Unsupported format or combination of formats in buildIndex using FLANN algorithm

The following runtime error may occur.

error: OpenCV Error: Unsupported format or combination of formats (type=0 ) in buildIndex_, file /tmp/buildd/ros-fuerte-opencv2-2.4.2-1precise-20130312-1306/modules/flann/src/miniflann.cpp, line 299

I had the same problem it seems that Flann needs the descriptors to be of type CV_32F. Try doing this before matching:

descriptors_1.convertTo(descriptors_1, CV_32F); descriptors_2.convertTo(descriptors_2, CV_32F);

See also

• Feature matching
• OpenCV

Favorite site

• FLANN - Fast Library for Approximate Nearest Neighbors
• Object detection with SURF, KNN, FLANN, OpenCV 3.X and CUDA

OpenCV

• Feature Matching with FLANN