[MOD] Histogram

[Joss]

Hi all,
it seems to me, that histogram is wrong in some case. Look for this:
http://gallery.imagemaster.ru/img8184.htm
http://gallery.imagemaster.ru/img8103.htm

You can save the pictures and open them in Photoshop and compare histograms. I think the problem arises in case when too many pixels in shadows (left side of histogram). It looks like a non-normalize histogram. Does anybody have any ideas?

Also, there is another problem - the histogram images don't remove from server when we remove the the image. Does anyone have a solution?

Thanks!

[Acidgod]

only scaling is diffent i think...

[Joss]

Acidgod,
thanks for the reply. I think so. But scaling is different only in some cases (as I've describe above). So, probably there is a decision of this problem? Anyway, I'll try to understand the code and find a solution.

[Acidgod]

can make some screenshots? where i can see the differents between Photoshop an this Mod?

[Joss]

Ok, I'll prepare it now.
But I found the "root of evil", it's a following code:

Code: [Select]

$max_value=max($max)/150;
 $m[0]=max($r);
 $m[1]=max($b);
 $m[2]=max($g);
 $max_rgb=max($m)/150;

If we change 150 to 450 e.g., on my examples we get a right scaling histogram. But for other images,  the histogram will overflow top line (sorry for my English, I'm from Russia). 

[Joss]

There is an example of histograms for the image:
http://gallery.imagemaster.ru/img8103.htm

Photoshop histogram is above, 4images is below.

[Joss]

I'm sorry, why I can't see this thread in "Mods & Plugins (Releases & Support)" branch?

[Acidgod]

(sorry for my English, I'm from Russia). 

And i am German... (o:
My English is not even better... *g

I'm sorry, why I can't see this thread in "Mods & Plugins (Releases & Support)" branch?

Too much sticky Threads... )o:
http://www.4homepages.de/forum/index.php?board=15.200
There you can find it... (11 site)

And that is a problem only with black and white images, right?

[Joss]

Thanks! I already tried so and so....
No, the problem not only with b/w images. It seems to me that the problem with all pictures (b/w and color) which have a lot of 0,0,0 and 255,255,255 pixels. In other words with images who have a "splash" in shadow/higlights.

[Joss]

I think that the following algorithm can fix the situation (I'll describe it by words) :

1. In

Code: [Select]

$max_value=max($max)/150; and $max_rgb=max($m)/150;
we must ignore values with indexes with range (for example) 0 ... 20, and from 235 ... 255. Especially because in that range can get black/white frame of image.

2. Instead of search the ONE max value we must find the max value with some density (by other words, the max values is a value which have some pixels in 20..235 range (e.g. 10 or 20).

[Frank Götze]

Hi mawenzi,

thanks a lot for this great mod. 

Frank.

[mawenzi]

Hallo Ivan,
... so wie es aussieht, hast du ja die Version von meiner Website installiert ...
... werde mir die Sache mal ansehen ...
... aber wenn es zunächst bei dir mit einer .htacess funktioniert, dann bist du ja schon ein Schritt weiter ...
... und wenn es an "register_globals on" (auch meine Einstellung) liegt, dann ist es ja ein Serverproblem ...

[barabangel]

My histogram is...




How to make it look like that one.

[mawenzi]

... here ... http://klick.kl.funpic.de/files.php ...

[barabangel]

  Thanks!