Distance travelled by a robot using Optical Flow

is there a way to find out the distance travelled by a robot using Optical Flow? For example, using OpenCV, I'm able to find out the velocity of each pixel between 2 images taken by a camera. However, I don't know where to go with this to find out the corresponding distance travelled by the robot. Can you suggest a way to do this?

My main aim is to do the localization of the robot and for that I need the distance travelled by it between 2 开发者_JAVA百科instances.

No, not directly. You can determine distance to objects, and then back calculate distance travelled from there, but it will likely be computationally expensive.

What you are lookig is a SLAM (Simultaneous localisation and mapping) method, that is also used in with feature matching methods using SIFT SURF or FAST. Read e.g. Quantitative Evaluation of Feature Extractors for Visual SLAM for more information.