Re: "Set Threshold" records incorrect values - 16bit images - Ubuntu

Posted by Ghislain Bugnicourt on Aug 26, 2008; 8:20am
URL: http://imagej.273.s1.nabble.com/Set-Threshold-records-incorrect-values-16bit-images-Ubuntu-tp3695217p3695244.html

Dear Wayne,

Thanks for your response. I'm sorry because I didn't expose it clearly enough : the problem with 'Threshold, set' is not present on the Windows and Mac ImageJ files.
Actually, I only found this problem on Ubuntu, and more recently on Debian. Therefore, it seems that the linux installing file has a problem. I join my previous message to explain what happens.

Thanks a lot for your care.
Ghislain Bugnicourt
CNRS - CRETA - France

Ghislain Bugnicourt wrote

Hi. First of all, thanks for this wonderful customizable imaging tool.

My issue is about the "set" option of the "adjust...threshold" tool, on 16-bit grey-scale images. I didn't find such a problem in the archive.
In this "set" dialog box, if I enter values that are not available with the scrolling bars, it modifies the values. For instance, 107 becomes 9, 940 becomes 104, 372 becomes 107, following a law I couldn't understand, and depending on the image. The images I obtain (even when doing 'apply') respect those wrong numbers.
But what is incredible is that sometimes it works well in exactly the same conditions (1/10 times).

Configuration :
 - Ubuntu 8.04 (There's no problem on Mac and Windows. But I couldn't try another Ubuntu 8.04)
 - The compiz bug (blank images) linked with Java was previously corrected by canceling the visual effects in Ubuntu.
 - ImageJ 1.41j, with Java 1.6.0_05
 - 16-bit images obtained with Metamorph (immuno-fluorescence on neuron cultures)