Easy Enhance Photo Color

Odinbc · **Posted:** Sun Feb 24, 2013 4:50 pm **(#1)**

Original image

Here is a quick and easy way to enhance photo color using, Border Average and Color to Alpha.

Open your photo in Gimp.
Layer menu | Duplicate Layer (Shift+Ctrl+D).
Select | All (Ctrl+A).
Color | Info | Border Average, Border Size - Thickness: 3, Number of Colors - Bucket Size: 16, OK. You can experiment with the Thickness and Bucket Size depending on the original photos condition. I would generally use a Bucket Size of 8-32 colors.
Select the Foreground color, copy the Hex color code. (The Foreground color will have changed to the results of Border Average*)
Colors | Color to Alpha, select From: [color], paste Hex color, OK.
Layer | Merge Down and your done!

*If your not happy with the color generated with Border Average, experiment with a selection inside the canvas area with the most color variation before you run Border Average.

K1TesseraEna · **Joined:** Sep 22, 2012 **Posts:** 2089 **Location:** US

Very interesting, Odin. How did you ever get to find this color boost effect?
When i was an amateur gimp user i would simply adjust contrast-brightness, now i'm using the whole range of available tools for that and even some scripts (like color vibrance). I've made a run with some images using your tut and other methods i've been using for some time now. They all result in different degree of color enhancement. Thanks for showing another way to do it. And the choice of technique depends on image you're dealing with, can't agree with you more on that.

Akros · **Joined:** Jan 10, 2013 **Posts:** 863

K1TesseraEna wrote:

Very interesting, Odin.(...) I've made a run with some images using your tut and other methods i've been using for some time now. They all result in different degree of color enhancement. Thanks for showing another way to do it. And the choice of technique depends on image you're dealing with, can't agree with you more on that.

Odin,
I say the same as above
I'm bad at assembling phrases in English, so speak little. But K1t expressed well what I wanted to comment! (thx K1t)
Always good to see different techniques. Makes us more flexible when we have to try to get a result in image editing.
Thx!

K1TesseraEna · **Joined:** Sep 22, 2012 **Posts:** 2089 **Location:** US

@Akros You said it well enough using your own words, please don't be shy, your English is fine. I always understand what you're saying,anyway.
I don't even pay attention to grammatical errors or typos (I do them myself quite a lot) as long as a person makes sense, and you most certainly do.

Akros · **Joined:** Jan 10, 2013 **Posts:** 863

K1t, very kind of you. :roll:

I appreciate your words and I'll try to be more confident. :bigthup

Thank you so much! :tyspin

Odinbc · **Posted:** Mon Feb 25, 2013 1:02 am **(#6)**

K1TesseraEna wrote:

Very interesting, Odin. How did you ever get to find this color boost effect?
When i was an amateur gimp user i would simply adjust contrast-brightness, now i'm using the whole range of available tools for that and even some scripts (like color vibrance). I've made a run with some images using your tut and other methods i've been using for some time now. They all result in different degree of color enhancement. Thanks for showing another way to do it. And the choice of technique depends on image you're dealing with, can't agree with you more on that.

To be honest it was by accident. I already was familiar with Border Average; I was playing with Color to Alpha and decided to use use them together. I liked the result so I thought I'd share it.

anarkhya · **Posted:** Mon Feb 25, 2013 5:01 am **(#7)**

Odinbc wrote:

I already was familiar with Border Average

I completely missed the meaning (and potential) of this tool, it can be very useful for quantization needs, I only read border (thinking border as in a.. solid border) and skipped the part where it's say average oO
Fortunately, you brought this back to the table. Thanks !

I'm still a bit confused by "border thickness" here, the thicker the border means... the bigger the sample extracted for averaging ?

dinasset · **Posted:** Mon Feb 25, 2013 5:43 am **(#8)**

Very nice!
On my test I got better results by changing layer mode to overlay before merging down

Odinbc · **Posted:** Mon Feb 25, 2013 1:06 pm **(#9)**

anarkhya wrote:

Odinbc wrote:

I already was familiar with Border Average

I completely missed the meaning (and potential) of this tool, it can be very useful for quantization needs, I only read border (thinking border as in a.. solid border) and skipped the part where it's say average oO
Fortunately, you brought this back to the table. Thanks !

I'm still a bit confused by "border thickness" here, the thicker the border means... the bigger the sample extracted for averaging ?

The border thickness to me means from the edge of the canvas in pixels, so yes the sample would be bigger. You can use it with selections as well. I've read the Border Average help; I would like to find a more technical description myself.

alc59 · **Posted:** Mon Feb 25, 2013 1:15 pm **(#10)**

Little bit of info on it here
Gimp book

Odinbc · **Posted:** Mon Feb 25, 2013 1:21 pm **(#11)**

dinasset wrote:

Very nice!
On my test I got better results by changing layer mode to overlay before merging down

Good to know, Overlay does add intensity to the layer below :bigthup

It's always fun to experiment with layer modes.

anarkhya · **Posted:** Mon Feb 25, 2013 8:10 pm **(#12)**

alc59 wrote:

Little bit of info on it here

odinbc wrote:

I would like to find a more technical description myself.

So, this border thickness input is to be treated like a ... simple border. I guess that's why gimp docs didn't dig the subject. Clean and simple. (:

dinasset · **Posted:** Wed Feb 27, 2013 3:58 am **(#13)**

to odinbc (and other guru on python):
because I like the effect you proposed on this tutorial, I tried to implement a python script to perform these steps, but I encountered a strange error: while the borderaverage plug-in works perfectly when executed directly on the screen, it seems not to work when called inside a python script, neither launching the script not even trying the function on the python console; in both cases, when plug-in borderaverage is called, it start work for a while then crashes ("no return value").
I did evaluate my script using Komodo, both performing a syntax check and simulating the run: no errors.
Any idea about?
Many thanks