用于做机器视觉的，来自px4的源码,http://www.amobbs.com/thread-5525773-1-1.html-the code from px4 PX4Flow is an optical flow camera. Provides optical flow at 250 Hz. Unlike mouse sensors it works indoors without illumination LED. Details. ■168 MHz Cortex M4F

Gradient Vector Flow (GVF) snake is one kind of active contours - curves that can move within images to find the boundaries of objects. 3D active contours are also known as deformable models. GVF snake begins with calculating the GVF force field over