Difference between the Smooth function and the Mean filter?

Hi all,

Stupid question but what is the difference between the Process > Smooth function and a mean filter with a radius of 3 ?

According to the documentation, it should be the same (or maybe I misunderstood) but the results are different.

run("Blobs (25K)");
run("Duplicate...", " ");
run("Duplicate...", " ");
selectWindow("blobs-1.gif");
run("Smooth");
run("Measure");
selectWindow("blobs-2.gif");
run("Mean...", "radius=3");
run("Measure");

Thanks !

I’m pretty sure the equivalent would be a mean with a radius of 1.

The radius setting for the filters is actually the center pixel plus one (a radius setting of 1 is a diameter of 3).

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Indeed, setting up a radius of 1 for the mean filter works and gives the same result.

I knew it was something stupid ^^’.

Thanks a lot :slight_smile:

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No problem, I only know because I’ve had similar confusion in the past!

I worked it out by making little images of 5 x 5 pixels and setting the centre one to 200 or something and testing what all the filters did. :slight_smile:

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