Simple whitepoint correction

[Lord Crc 0]

This is a simple "whitepoint" correction plugin. It's ideal for images which have a slight color tint, and which contains some pixels which should be neutral grey.

I wrote this plugin as my mobile camera usually ends up taking images with poor color balance, and I wanted a simple tool to correct it. I'm publishing it in case anyone else finds it useful.

Usage:

1. Select the Color Picker tool.
2. Use the Color Picker to select a Primary Color which should be neutral grey.
3. Select the Adjustments menu and select the Whitepoint plugin.
4. If not satisfied, undo, try another color and run it again.

Here's an illustration image.

Example:

Before image

After image

How it works:

The plugin will apply a photo filter-like effect on the image using opposite color of the selected Primary Color, while preserving the brightness of the source color. For example, if the Primary Color is blue-green (cyan) it will apply a red photo filter.

Download:

http://partialgeek.n...tCorrection.zip

Notes:

• Distributed under the LGPL license, the .cs file is for use with the CodeLab plugin, ignore it if you don't want to look at or modify the code.
• Note that picking a color from a uniform area works best, the brightness of the color is much less important. For the example picture below I picked a color from the shadowed area on the napkin, as can be seen in the illustration image above.
• For images with a lot of color noise it may be beneficial to downsize the image before picking a color to get a better basis color for the filtering. Undo the resize after you've picked the color.
• As always "garbage in = garbage out". This filter cannot undo destructive processes, so for example washed out highlights may not look good. It works best for images with a slight tint.

Hope you enjoy

Edited January 31, 2012 by Lord Crc

[pdnnoob 261]

Very nice! This will actually be useful to me in the near future.

[Lord Crc 0]

Thanks

[yellowman 209]

It really works, I like the idea of neutral grey, so clever, thanks.

Picking different colors on same photo gives some nice results, too .

[delpart 15]

Well in cursory testing it can provide some alternatives as well for a color tint wash like YM indicated. Done mainly on primitives and the negation aspect is different than White Balance or most auto leveling passes. Definitely GIGO as well based on user selection as well as image density.

Thanks for sharing up your efforts on this.

[nitenurse79 605]

Where does the included CS file go? please

[delpart 15]

That should just be the source code file in C or C# or C whatever. In theory you can diregard this file unless you plan to delve into how its constructed, etc

[Lord Crc 0]

Sorry forgot to mention that the CS file is for use with the CodeLab plugin

If you don't want to look at or modify the code, feel free to ignore it

Edited January 31, 2012 by Lord Crc

[Lord Crc 0]

Well in cursory testing it can provide some alternatives as well for a color tint wash like YM indicated. Done mainly on primitives and the negation aspect is different than White Balance or most auto leveling passes. Definitely GIGO as well based on user selection as well as image density.

Thanks for sharing up your efforts on this.

Thanks! I must admit I haven't explored the more creative uses of this plugin, fun

[nitenurse79 605]

Ok, thank you for that. I don't think I would be delving deeper yet

[TechnicGeek 0]

Pretty cool Lord Crc. I wonder if your plugin will let me accomplish what I am looking for.

Moderartor suggested I should try your plugin for what I want to accomplish. What I want to accomplish is commercial photography by applying proper touch up for photos I made with my old digital camera. My photos even when shooting on sunlight do not have enough lighting plus it feels as camera also leaves green tint on photos. The process is removing background, putting object on white background and adjusting it by raising light levels so although artificially, it looks like it was shot with enough lighting. Applying color adjustment later would be bonus and not as required as lighting. To give you example for what I am looking for, here's a link to "Before - After" photo:

http://imgur.com/a/0vlqM

Can you view them?

Another problem is that I am not savvy in knowing terms and adjusting parameters. Would that be obstacle?