Post Reply 

GIMP 2.8.10/Win. 7 Prof., 64 Bit: Transparency, preserve color, use non-used color

Jun 23, 2014, 22:29
Post: #1
GIMP 2.8.10/Win. 7 Prof., 64 Bit: Transparency, preserve color, use non-used color
A first hello,

I'm familiar with the basics of transparency. Let us assume I have a picture of an technical device ("object") with an white background. Now I want to set white as transparent color. But usually any object contains the backgroud color - here white.
How do you handle such a case? What is the most convenient way to slightly modify such a color in the object? Is there a way to find a non-used color in the picture which could then be used as background? Any other suggestions?


Many thanks and greetings
ypmig
Find all posts by this user
Quote this message in a reply
Jun 24, 2014, 00:10 (This post was last modified: Jun 24, 2014 00:12 by fluffybunny2.)
Post: #2
RE: GIMP 2.8.10/Win. 7 Prof., 64 Bit: Transparency, preserve color, use non-used color
Hi and welcome.
Firstly I suggest you have a read of the techniques described here.
Without seeing the image, I guess you could try the Fuzzyselect tool adjusting the tool options (threshold, Select by: etc) if the background is just a single color. Once you have the background selected use Edit->Clear to remove.
Hope this helps in some way.
Wink
Find all posts by this user
Quote this message in a reply
Jun 24, 2014, 00:32 (This post was last modified: Jun 24, 2014 00:32 by ofnuts.)
Post: #3
RE: GIMP 2.8.10/Win. 7 Prof., 64 Bit: Transparency, preserve color, use non-used color
(Jun 23, 2014 22:29)ypmig Wrote:  A first hello,

I'm familiar with the basics of transparency. Let us assume I have a picture of an technical device ("object") with an white background. Now I want to set white as transparent color. But usually any object contains the backgroud color - here white.
How do you handle such a case? What is the most convenient way to slightly modify such a color in the object? Is there a way to find a non-used color in the picture which could then be used as background? Any other suggestions?


Many thanks and greetings
ypmig

See the link posted above by FB. Basically you do a selection that includes the background plus the edge pixels of the object, and use Color-to-alpha. The inside of the object is not part of the selection and therefore left unchanged. The link above also tells you why using plain delete/clear will not produce good results.

To change the background the same link show you how you can use the paint tools in "color erase" and "behind" mode.

Now answering your questions on
https://Gimp-Forum.net
Visit this user's website Find all posts by this user
Quote this message in a reply
Post Reply 


Possibly Related Threads...
Thread: Author Replies: Views: Last Post
  Need Help about Gimp opening a whole lot files AlexWorX 1 77 Nov 17, 2017 19:44
Last Post: rich2005
  How do I open multiple images in Gimp? Pnem42 1 78 Nov 9, 2017 05:23
Last Post: paynekj
  not able to draw different color rectangles manish 1 69 Nov 3, 2017 04:01
Last Post: ythgilb
  Gimp prints multi page documents on one page samksharma 1 126 Oct 17, 2017 04:49
Last Post: paynekj
  Desaturate to color KWiK 2 151 Oct 9, 2017 22:14
Last Post: KWiK

Forum Jump:


GIMP ForumPortalArchiveContactTermsRSS