Differences between OpenCV SURF and OpenSURF?

I am trying to use (SURF(opencv); [OPENSURF c++;OPENSURFC#] OPensurf http://www.chrisevansdev.com/computer-vision-opensurf.html), SIFT for image matching.

1. I have the feeling that SIFT is more accurate at the time of cost than SURF(OpenCV).

2. OpenSURF takes more time than OpenCV SURF

3. Any accuracy tests for SURF/OpenSURF/SIFT?

Have you tried any? 开发者_如何转开发What were your results? Which is better and why?

SIFT extracts more key features from an image. In an 70*70 average face photo SIFT extracts nearly 40-50 features, however SURF extracts nearly 8-10. SURF is faster than SIFT, however their benefits changes according to application you want to make. For example in face recognition some of beneficial features may be missed in SURF so with my trials I saw SIFT is more beneficial and accurate in applications like face recognition because it extracts more features.