How can I fit a curve on a detected edge?

Hello,

I am working on a project which requires me to compare the growth rate of a particular process to some simulations. I currently have a video for the growth process and have used edge detection to see the boundry at each frame. How can I fit a curve at each frame and store it in an array? Later I want to compare the similarity between the simulated growth rate and the observed growth rate.

P.S. I am pretty new to matlab and programming in general. Please let me know if you need any more details.

[J. Alex Lee]

How about an example frame showing the shape, or your edge representation of the shape? What measure of "size" are you using to track "growth"?

Likely you don't actually need to fit a curve to the perimeter - you probably just want toa measure of the perimeter, and/or the area enclosed by it, both of which should be easy to get with an analysis of "connected components" using image processing toolbox tools.

If you do actually need to fit a curve, the complexity of help/answer will depend on the shape of the thing you are tracking.

[Image Analyst]

You forgot to attach the video or even a frame from it.

Why can't you just segment the growing thing and look at area as a function of time? Why do you need to find the edge of it? And why fit it to a function??? And what functional form did you have in mind? A paraboloa?

If you have any more questions, then attach your data and code to read it in with the paperclip icon after you read this:

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