How do I plot a trajectory of an object in video.

I have a video of a test subject moving around and I need to plot it's where abouts over a time period. The subject has a distinctive red color while the background is mostly white. How can I record it's (x,y) whereabouts and then plot them?

[KSSV]

Not clear...you have a video and you want to plot the trajectory of the object from video...or you want to make a video of the trajectory?

[Shachar Givon]

I have the video and want to plot the trajectory of the object from the video

Answer 1

[Image Analyst]

Find the red object first. The Color Thresholder app on the Apps tab of the tool ribbon might be helpful. Or else see my File Exchange. https://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862&sort=downloads_desc

Then save the (row, column) or (x, y) location of the red object in a loop over frames and plot it.

x(frameNumber) = column;
y(frameNumber) = row;
cla;
plot(x, y, 'r-', 'LineWidth', 2);
grid on;

Answer 2

[Lucy Davidson]

Did you manage to do this?? I am trying to do a smililar thing and I am quite confused. I had made the back ground white and the animal i am tracking black