how can i get the area of a ball with video analyis

[wido]

hallo
if i have video analysis for a ball,how can i get the area?

[Meadow]

Hi Wido,

So what kind of video analysis that you have done? You may want to post what you have done and difficulties that you are facing so that we can help you further.

[wido]

hi Meadow
thanks for ur answer,so i make analysis for a hyperelastic material with pressure,so they get blowed,and i use two cams,and witihnthat i have to get the area oh tis small ball,i hope u get me,when not i can send u a description on email,can u please help me?

[Taki1999]

Can you post some sample images?

Are you looking for projected area or an estimate of surface area?

[wido]

can u please send me ur email to send u a sample?
thanks alot.

[Taki1999]

You should be able to post directly to the forum.

You'll get better help if more people can see what you're trying to do.

If you've picked your image setup judiciously, you should be able to use Vision Assistant or Vision Builder to threshold and then perform particle analysis to obtain area.

[wido]

ok thnks,
how can i also get the curvatures at top.it is the radius at top,?

[Taki1999]

I don't have the Vision VIs on the computer I'm at right now so I'm posting from memory but I believe that there are parameters from elliptical fits that are output from the Particle Analysis VIs.

If you need metrics not provided by the particle analysis VI's, you may have to use edge detection and write your own routines to process the data.

[wido]

hi taki
i was trying with vision assistant but i coud nt do it,can u please tell me about the steps that i shoul follow to do get the area,thanks.

[Taki1999 · Accepted solution]

Vision Assistant Steps:

First clean up your image to maximize contrast between your ball and the background.  This is usually a combination of smoothing/blurring/despeckling.

Then run a Threshold to generate a binary image which ideally only contains your ball.

The use the Particle Analysis to obtain information about the ball.  One of the outputs of the Particle Analysis step is the area.

Most of the difficulty in this type of analysis is getting a clean enough image to work with.  If you can post a sample image, I might be able to generate a Vision Assistant Script which does the steps described above.