LocalHistogramEqualization module

[zvrastil]

Hi all,

I'd like to announce my new module here. It implements local histogram equalization. The process is based on method CLAHE (Contrast-Limited Adaptive Histogram Equalization). It basically does local contrast enhancement and improves visibility of structures in low contrast regions.
You should get the module soon through Automatic Updates from the main repository.

In the meantime, you can read something about the module at my webpage:
   http://astrofoto.euweb.cz/pixinsight/modules.html.

In particular, there is a reference documentation with more details on method and its parameters (will be part of installed module):
   http://astrofoto.euweb.cz/pixinsight/LocalHistogramEqualization/LocalHistogramEqualization.html

and an example showing effect of two main parameters of the method on testing image:
   http://astrofoto.euweb.cz/pixinsight/LocalHistogramEqualization/comparison.html.

I would like to thank Vicent, who kindly gave me this excellent image of M42 for testing.

Please understand that despite I implemented the method, I did not invented it and I am by no means expert in using it. If you find good use for this module, please share it.

best regards, Zbynek

[Carlos Milovic]

Excellent work! I always wanted to write something like this The results are pretty good. Congratulations. I'll try it ASAP.

[Nigel Ball]

Zbynek

Excellent work!

I've just updated PI and tried the LHE module on a couple of images I'm working on. It should help me enormously  8)

Nigel

PS I couldn't get the mouseover functions to work at all on the examples of M42 on your website though

[Enzo De Bernardini]

Excellent Zbynek! Thanks for your work! It looks really useful. 

Enzo.

[Alejandro Tombolini]

Thanks Zbynek, it will help a lot. Excellent script.

Alejandro

[zvrastil]

Thanks all. I hope you'll find the module useful.

PS I couldn't get the mouseover functions to work at all on the examples of M42 on your website though

Yes, it seems it does not work in IE (it works in Firefox for me). IE reports some error on the page. I'll check in the evening, now I'm in the office.

regards, Zbynek

[Redshift]

Hi Zbynek,

Thanks for this, I'm certain I'll find this useful. I use to use Photoshop for this.
I've downloaded it in PI 32 and 64 bit for the Mac, but the documentation 'window' is blank in both cases. Have you any suggestions as to why.

regards
Dave

[zvrastil]

Hi Zbynek,

Thanks for this, I'm certain I'll find this useful. I use to use Photoshop for this.
I've downloaded it in PI 32 and 64 bit for the Mac, but the documentation 'window' is blank in both cases. Have you any suggestions as to why.

regards
Dave

Hi Dave,

I also removed my local module and updated it from main repository to have same situation as everyone. And I see the documentation without problem (on Win32bit). Did PixInsight reported 2 updates? There should be two - one for module binary and one for documentation. You could also check your doc/tools folder (if I remember it correctly from the top of my head) - there should be LocalHistogramEqualization.html file.
Do you see documentation for my older modules Annotation and AssistedColorCalibration? They are distributed in the very same way.

In the meantime, you can check the documentation under the link http://astrofoto.euweb.cz/pixinsight/LocalHistogramEqualization/LocalHistogramEqualization.html - it is the same one.

regards, Zbynek

[zvrastil]

PS I couldn't get the mouseover functions to work at all on the examples of M42 on your website though

Yes, it seems it does not work in IE (it works in Firefox for me). IE reports some error on the page. I'll check in the evening, now I'm in the office.

Should work now. I tested it in IE, Firefox and Chrome.

[Redshift]

Hello Zbynek,

Thank you for your reply. Yes, PI did report 2 updates in both cases.

Dave

Hi Dave,

I also removed my local module and updated it from main repository to have same situation as everyone. And I see the documentation without problem (on Win32bit). Did PixInsight reported 2 updates? There should be two - one for module binary and one for documentation. You could also check your doc/tools folder (if I remember it correctly from the top of my head) - there should be LocalHistogramEqualization.html file.
Do you see documentation for my older modules Annotation and AssistedColorCalibration? They are distributed in the very same way.

In the meantime, you can check the documentation under the link http://astrofoto.euweb.cz/pixinsight/LocalHistogramEqualization/LocalHistogramEqualization.html - it is the same one.

regards, Zbynek

[zvrastil]

Thank you for your reply. Yes, PI did report 2 updates in both cases.

I'm afraid I have to leave this problem to Juan. I do not think it's related to the module.

Zbynek

[georg.viehoever]

I'm afraid I have to leave this problem to Juan. I do not think it's related to the module.

My guess is that it is related to all Internet Explorer versions (or old versions of their support libraries). IE initially did not support .PNG, and I don't know if this changed with later IE versions on Windows XP. Display of screenshots work fine with on Win7.

Georg

[JGMoreau]

Hi Zbynek,

Thank you very much for the new LocalHistogramEqualization module,
it did a great job on the faint nebulosites in my latest image :

http://www3.cablevision.qc.ca/astro/IC444.jpg

Jean Guy Moreau
Quebec

[RobF2]

Impressive work, and thanks so much for the effort put into your documenting webpage (not to mention the online documentation).  What a pleasure too to be able to ask for an update and have this install itself. 

Thanks again Zbynek

[pfile]

really strange - i downloaded this in mac x86-64 and it appeared in the process menu after a restart. then PI crashed, and when it came back, the process was gone. is there some kind of xml file or other pref file that points to these modules, or if the shared library is in the right directory does PI just go ahead and load it?