7

I had this image:enter image description here

Which I applied a transparency background:

enter image description here

However, the result isn't perfect at all, as letters still have white borders. You can see this in the following zoom:

enter image description here

What wrong did I do? Or do I have to do something more to remove those white thin borders?

EDIT: it's not only the text that is a problem as the graph also has white borders:

enter image description here

3
  • Hi. Welcome to GDSE. I think the best way to fix it would be to retype the text (and erase the old text). It's just Arial. Trying to edit pixels around text is a bad idea.
    – Billy Kerr
    Jun 7, 2019 at 18:01
  • @BillyKerr Thank you for your comment Billy Kerr. What you suggest did work for the text. I edited my question according to the remaining issue.
    – JKHA
    Jun 7, 2019 at 18:44
  • Sidenote: Vector graphics are much better suited for handling that image than pixel graphics and it should be rather easy to recreate it as a vector graphics from scratch.
    – Wrzlprmft
    Jun 8, 2019 at 14:17

3 Answers 3

9

Usual technique:

  1. Do a wand select of the background
  2. Shift click in any isolated areas that you want to remove (loops in "O", "P"...)
  3. Select>Grow by one pixel so that the selection bleeds over the pixels at the edge of things.
  4. Color>Color to alpha and remove the white

Result: put over contrasting backrground:

enter image description here

(yes, there is a small miss in the sharp angles of the 'M', easy to solve by adding a bit of selection there before the C2A step (doesn't even need to be accurate).

The why of this process is explained here

0
2

Redrawing those graphs in a vector graphics application - for example Inkscape - should not be that hard and will get you very nice results, especially if you need different sizes where you'd like to do simplifications for them.

This is also most likely how this image was created in the first place, so if you could get the original, you might be a lot better off. Otherwise, I'd take this as a training exercise to learn a vector graphics application.

If you want to stick to GIMP, you could do the following:

Then you can zoom into a border area and use Clear from the Edit menu - a very convenient way to do this is to use its default keyboard shortcut, the Delete key on your keyboard, repeatedly.

This will delete everything that's selected, but due to the soft nature of the feathered selection outline, will only do so gradually along those borders. They will become transparent, the white will go away and they should be a much better fit over different backgrounds.

1
  • Thank you, I installed Inkscape, but it seems to take me too long for succeding what I wanted as a full beginner with noone to teach me. I +1 you ;)
    – JKHA
    Jun 7, 2019 at 21:53
1

Select the polygon-star pattens with the lasso tool, cut and paste the them to a new layer. leave the texts to the original layer. Have also a spare copy of the image for just in case of errors.

enter image description here

Process the layers differently. In the text layer convert white to alpha. In the star-pattern layer select the white exterior with the fuzzy selection tool, expand the selection (=Select > Grow > 1px) one pixel and convert again white to alpha. The result:

enter image description here

I agree with Mr Kerr. You get the best text result by rewriting them. Equally the best result from the rest can be got by redrawing all in a vector program. I'm not at all sure is it useful to tinker in GIMP when the image is this simple and easy to redraw.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.