Pixel tracking and motion estimation code?

Hello,

I am a beginner and this is what I want to do : From a recorded video, I would like to track a pixel(s) and extract its velocity over the time. I know I have to use the optical flow method (HS) to define the velocity field, but how to define it for a moving pixel (and not a xy location)? How to extract its value over the time?

Does anyone has a similar code to propose?

Thank you

Answer 1

[Image Analyst]

Optical flow is good where the whole scene kind of morphs like if you want to track clouds or plants swaying in the breeze. Object based methods are good if you're tracking things like isolated objects (cars, balls, people, etc.) and most of the scene changes little. The Computer Vision System Toolbox has tracking tools to help you.

[Kevyn]

Thank you for your answer. It is not the theory which blocks me but the processing. Could you be more specific about which tool I should use and how to do it if you do not have a example? As I said, I am a beginner.

[Image Analyst]

I have not used optical flow, or the Computer Vision System Toolbox, so I can't help you. You can call the Mathworks for help with the toolbox if you can't get their demos to work. I don't believe there is any optical flow functionality built in to any of the Toolboxes, so you're on your own there.