Measure the droplet diameter

Dear KNIME developers and Users,

I am doing a project that is required to measure the droplet diameter. I am trying to measure the diameter by analyzing the image. Can some one could give me a hint to cope with this problem? what could be the workflow for this task? I include my sample picture below.
Hope to have some support from the community.
thank you very much!
IMG-0715|690x318

@gab1one could you help me with this task? please

Hi,

maybe this topic is related to yours and could somehow inspire you how to start:

Best,
Martyna

1 Like

Hi @Martyna,
I am very glad for your response
I’ve tried to start with simple work to detect the droplet but when I crop the image to apply the Global thresholder but it turned out not working.
IMG_09800014


what could I do to improve the detecting algorithm?
thank you

and the data from the the interactive table. How can we convert it from pixel to mm? is there any node or method to convert the unit in Knime?
I measure and got some result but I could not convert it back to mm
thank you

Hi @TruySaigon,
I would start by subtracting the average over all your images from each image. If you look into the linked post there should be a bit on it, if you upload a few more example pictures, I can take a look myself.

best,
Gabriel

3 Likes

Thank you for your reply!! @gab1one

These are some sample pictures that I would analyze.
IMG_09820098 IMG_09820099 IMG_09820102 IMG_09820105 IMG_09820106
I just need to calculate the diameter of these falling droplets.
I would be very grateful if you could help me with this problem, please

Thank you very much

Hi @gab1one,
I had attached some sample pictures
I hope that you could have a look at them.

thank you very much
best regards

High @TruySaigon,
the images that you uploaded are very small, I can’t really do much with them. I thought you would upload a few more like the one from your first post.

best,
Gabriel

1 Like

Hi @gab1one,
these are the original pictures of them.
I thought I might change them to a green background for better detection.

I hope that you could have a look at them, please!!!
thank you very much
best regards,
Duy

Hi @gab1one,
I have re-upload the raw pictures of falling droplets above.
I hope that you could have a look at them, please.
thank you very much
I am looking forward to hearing from you

Hi @gab1one,
After reading through some reference,
I have come up with the workflow in the attached file.
but when I tried out with different flow rates, the results are not consistent.
in the Quantile Filter node, I always have to vary the value of quantile and span numbers.
To be honest, I haven’t known how to correct those values.
I hope you could have a look at the workflow and suggest some ideas that I could improve it.

Thank you very much
I am looking forward to hearing from you
Best regards,

Duy
Droplet Area.knwf (463.3 KB)