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Logo Help

Feb 9, 2011, 01:49
Post: #1
Logo Help
Hi Friends,

I need help with a little project... I have a color logo on a white background that I need to be a white logo on a transparent background so I can layer it over color. I have tried a number of approaches as this seems like it should be dead simple, but I can't seem to figure it out.

Logo is attached for reference.

Thanks,
RYO


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Feb 9, 2011, 02:10
Post: #2
RE: Logo Help
Hi RYO,

Check out the following thread that explains how to remove the background: Removing the background of an image

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Feb 9, 2011, 17:16 (This post was last modified: Feb 9, 2011 17:16 by IAMRYO.)
Post: #3
RE: Logo Help
Einherjar,

Thanks for the link, that definitely helped me out and was extremely easy. Now I'm stuck on making the logo white. I've tried inverting colors and playing around with hues, contrast, etc...

I can tell I'm doing it wrong, but can't figure out how to proceed.

Thanks,
RYO


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Feb 9, 2011, 19:24
Post: #4
RE: Logo Help
Windows -> Dockable Dialogs -> Layers
Check 'Lock alpha channel' box for the layer

Select you logo with 'Rectangle select tool'

Bucket fill the selection white (transparency won't be affected)
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Feb 9, 2011, 22:29
Post: #5
RE: Logo Help
Alright, so close... One more thing:

The logo is now white on transparent, but the white portion is semi-transparent... I can't seem to get it completely opaque. Any help on this will be a life-saver.

RYO


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Feb 10, 2011, 09:58
Post: #6
RE: Logo Help
You got a half transparent result because your original hasn't got enough contrast (I assume you used the color-to-alpha method). Your result seems also to indicate that the original images has irregularities as if it were scanned/photographed and isn't an original CGI or is a low quality JPEG. So I would restart from scratch and first cleanup the original image (unfortunately your attachment link seems dead, so I can't get it). You are also working with a very small image where every pixel counts...

Otherwise you have an alpha channel that goes from black to grey, and you want it to go from black to white, so the good way is to extract that alpha channel as a layer mask, and edit the layer mask with the color tools, so that you lightest gray becomes white (levels or curves, avoid threshold since that will remove partially transparent pixels that do some anti-aliasing). Find attached a quick shot with "levels".

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Feb 10, 2011, 17:17
Post: #7
RE: Logo Help
Wow. Thank you.

Here is my favorite plugin:
whitebalance
http://registry.gimp.org/node/72

It won't work on masks, but still...
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Feb 10, 2011, 17:47
Post: #8
RE: Logo Help
ofnuts,

Thanks for the help! Half of what you said is Greek to me, but I will try to follow your instructions and ask more questions if needed.

I wish I had a better original to work with... Our marketing department is a joke. I had to do a Google images search just to get something to work with Sad
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Feb 10, 2011, 18:20
Post: #9
RE: Logo Help
(Feb 10, 2011 17:47)IAMRYO Wrote:  ofnuts,

Thanks for the help! Half of what you said is Greek to me, but I will try to follow your instructions and ask more questions if needed.

I wish I had a better original to work with... Our marketing department is a joke. I had to do a Google images search just to get something to work with Sad
I got that one from GogleImage:

http://c0023576.cdn1.cloudfiles.rackspac...r_bm-1.jpg

Seems a lot better than yours.

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Feb 10, 2011, 18:36
Post: #10
RE: Logo Help
Haha, yeah I actually went back after saying that and found a much larger one too. I think originally I was searching more for the result I'm looking for and had entered all sorts of wacky search terms, excluding some better ones to start with.

So now I have a new original and I'm starting from scratch. I've added an alpha channel, then a mask:
Layer -> Mask -> Add Layer Mask -> Layer's Alpha Channel

Then I tried White balance and it worked on the text, but not the logo. How can I get the logo to go from the color it is with semi-transparency to black, then white?


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Feb 10, 2011, 21:07
Post: #11
RE: Logo Help
(Feb 10, 2011 18:36)IAMRYO Wrote:  Haha, yeah I actually went back after saying that and found a much larger one too. I think originally I was searching more for the result I'm looking for and had entered all sorts of wacky search terms, excluding some better ones to start with.

So now I have a new original and I'm starting from scratch. I've added an alpha channel, then a mask:
Layer -> Mask -> Add Layer Mask -> Layer's Alpha Channel

Then I tried White balance and it worked on the text, but not the logo. How can I get the logo to go from the color it is with semi-transparency to black, then white?

See attachment... you can read the full story from bottom to top:

1) a strong darkening with the Curves (looking at the histogram, all the picture is middle to high tones, so color-to-alpha with white is confused).

2) Then apply color-to-alpha with white. Works quite well... but see later

3) apply black to remove color: lock alpha channel, and bucket-fill with black

4) but closer inspection (magic wand, treshold=0, click on background) shows a) a blocky "halo" of not quite opaque pixels around the letters, likely due to JPEG artifacts in the original picture, and b) the Hi Visibility layer demonstrates a lack of opaqueness of the logo proper by showing through.

5) The cure: extract transparency channel to the layer mask, put a white background, and with the curve tool applied to the mask, truncate the darks so that the artifacts pixels disappear (they become filly transparent since their opaqueness becomes 0) but the anti-aliasing stays (opaqueness values beween 15 and 240). In the high tones, force everything above 240 to 255 to make the logo fully opaque (where the limit is is very visible with the histogram)

6) To get a white logo, invert the colors.

Dispose in XCF file and serve hot.

You've been lucky to find this bigger version, I was going to suggest to blow up your smal pic, and use that under inkscape to redraw the thing from scratch with vectors.

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