Does opencv allows to use ASIFT ?
http://www.ipol.im/pub/algo/my_affine_sift/
The creator published the c++ so I believe it wouldn't be so hard to implement it into opencv
What do you mean by
Does opencv allows to use ASIFT ?
At this moment, ASIFT is not available in OpenCV directly, but it should be a no-brainer to connect the code provided by the ASIFT authors to OpenCV. Probably all you'll have to do is to convert the OpenCV cv::Mat to some specific image format, by accessing Mat::data pointer.
If you are worried about licensing terms, you should contact the ASIFT authors. OpenCV is free to use/modify/redistribute/sell, under a BSD licence. And it seems that it is the same for ASIFT.
And if you are talking about integrating the code into OpenCV, and sending a patch to the dev guys, there is a guide on how to do it here http://code.opencv.org/projects/opencv/wiki/CodeSubmissions and here http://code.opencv.org/projects/opencv/wiki/How_to_contribute and here http://code.opencv.org/projects/opencv/wiki/CodingStyleGuide . I (and many others) strongly encourage you to do it! It seems to be an important addition to OpenCV.