Image correction

Ideas for improvements and requests for new features in XnView Classic

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thire
Posts: 118
Joined: Sat Jul 30, 2005 10:26 am

Image correction

Post by thire »

It would be cool to have an option to do some auto-correction of images (brightness, contrast, gamma, ...). Are there some algorithms to estimate "good" values?
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xnview
Author of XnView
Posts: 44821
Joined: Mon Oct 13, 2003 7:31 am
Location: France

Re: image corretion

Post by xnview »

thire wrote:It would be cool to have an option to do some auto-correction of images (brightness, contrast, gamma, ...). Are there some algorithms to estimate "good" values?
You have auto levels and auto contrast
Pierre.
thire
Posts: 118
Joined: Sat Jul 30, 2005 10:26 am

Post by thire »

oh, yes, I see. In the menu. Sorry.
If there was an "auto"-button in the adjust->brightness... dialog it could be helpful.
sorry for my noise. :mrgreen:
th
geometra

how

Post by geometra »

Hi Pierre:
Can you explain how do you apply auto levels transformation?

I know how Photoshop does it because it is explained at its help. They cut the histogram at the tails by 0.5% of the values previous to the expansion. Are you making any of this? It is important to me to know if I will loos some values if I apply auto-levels and how many.

Congratulations for your work!
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xnview
Author of XnView
Posts: 44821
Joined: Mon Oct 13, 2003 7:31 am
Location: France

Re: how

Post by xnview »

geometra wrote:Hi Pierre:
Can you explain how do you apply auto levels transformation?

I know how Photoshop does it because it is explained at its help. They cut the histogram at the tails by 0.5% of the values previous to the expansion. Are you making any of this? It is important to me to know if I will loos some values if I apply auto-levels and how many.

Congratulations for your work!
Yes i cut histogram too
Pierre.