evaluate diameter of moving bubbles

i'd like to measure the diameter of one or more moving bubbles. there's someone that already tried it? furthermore i'd like to Know the position of the center of a circular shape approximating the bubble.

[Sven]

What is your question? Be specific.

Yes, I tried measuring the diameter of moving bubbles once when I was on the beach... but I don't think that helps you.

[Walter Roberson]

It isn't clear to me that "diameter" of a bubble is a meaningful measurement. For example, how does one measure the "diameter" of the bubble shown at http://www.worldslargestbubble.com/gwr.html ?

Answer 1

[Hin Kwan Wong]

What's the acquisition device? From a 2D image or 3D model?

If you have good image processing so that the bubble is a silhouette or a 3D model

Then you can use data processing to find out the total area (for 2D) or volume (for 3D). This is then compared to the circle formula or sphere volume formula to find a equivalent diameter and translate it to real world units base on the image acquisition device

Answer 2

[Image Analyst]

Where did you post your image? You did post it somewhere before you asked here, didn't you??? Otherwise all I can say is to use image processing, or try out my BlobsDemo where I find the diameter of coins: http://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862

Answer 3

[Sean de Wolski]

doc regionprops

to find the center.