SIFT,SURF,ORB,FAST 特征提取算法比较

图像处理的基础就是要进行特征点的提取，feature(interest points) detect 的方法也在不断的进步，边检测，角点检测，直线检测，圆检测，SIFT特征点检测，同时描述符也在发展，为了匹配的高效，逐渐从高维特征向量到二进制向量…下面做一个简单的罗列，并调用opencv API看看效果！
承接上一篇文章。

Feature Detection Methods List:

• Canny Edge Detect, A Computational Approach to Edge Detection, 1986. The Canny edge detector is an edge detection operator that uses a multi-stage algorithm to detect a wide range of edges in images.
• Harris, A combined corner and edge detector, 1988. considering the differential of the corner score with respect to direction directly.
• GFTT，Good Features to Track,1994, Determines strong corners on an image.
• Matas-2000, Robust Detection of Lines Using the Progressive Probabilistic Hough Transform. 霍夫变换检测直线.
• SIFT,Distinctive Image Features from Scale-Invariant Keypoints,2004, invariant to image translation, scaling, and rotation, partially invariant to illumination changes and robust to local geometric distortion. 128-dim(512B).
• SURF, Speeded Up Robust Features,2006,受SIFT启发，比SIFT快，健壮. 64-dim(256B).
• FAST ,Machine Learning for High-speed Corner Detection, 2006,wiki. Very fast, not robust to high level noise.
• ORB, ORB: an efficient alternative to SIFT or SURF,2011，基于FAST和BRIEF，比SIFT快两个数量级，可作为SIFT的替代(a fusion of FAST keypoint detector and BRIEF descriptor). 32B binary descriptor.
• BRISK，BRISK: Binary Robust Invariant Scalable Keypoints, 2011. 64B binary descriptor.
• STAR，Censure: Center surround extremas for realtime feature detection and matching,2008,引用次数不高.scale-invariant center-surround detector (CENSURE) that claims to outperform other detectors and is capable of real-time implementation.
• MSER，Robust Wide Baseline Stereo from Maximally Stable Extremal Regions, 2002, 斑点检测(blob detection).

特征点提取算法比较(image dataset(27 pictures)):

上面是通过一些图片集测的单单是feature detect 的时间，接下来通过一对图片看看feature detect和compute feature descriptor总共花费的时间开销（秒）：

可以看到计算descriptor的开销还是很大的，这里仅仅两张图片，所以主要开始是计算描述符，提取是很快的。

下面通过通过两张图片来看这几个算法匹配的效果，1639-1311-697表示图片1，2分别提取了1639，1311个keypoints，其中匹配的有697个。

Canny Edge Detection效果：

Find line segments by probabilistic Hough transform：

Harris Corner Detection：

SIFT match效果图：

SURF match效果图：

ORB match效果图：

BRISK match效果图：

代码在这里

参考：
Canny Edge Detector Example
Feature Detection-Canny, HoughLinesP
Harris corner detector Example
BRIEF (Binary Robust Independent Elementary Features)
ORB (Oriented FAST and Rotated BRIEF)