# Revision history [back]

### When will all feature detectors be implemented in opencv 3?

Hi,

OpenCV 3.1 is the first version I am working with intensly. I wanted to compare all available feature detectors and use the winner with flann.

However, is seems that only ORB, KAZE, AKAZE and BRISK are implemented. I have not tried SURF and SIFT, because non-free is not an option for me.

FastFeatureDetector, MSER, AgastFeatureDetector, GFTTDetector and SimpleBlobDetector cause errors like:

OpenCV Error: The function/feature is not implemented () in cv::Feature2D::detectAndCompute, file d:\production\sources\3rdparty\xsopencv\opencv\modules\features2d\src\feature2d.cpp, line 144


I assume these have not been finished in OpenCV 3? When will they be or how can I make use of them as of today?

Thank you for any clarifications!