Manually selecting the regions you want to remain unchanged through bezier curves or other selection tool is what I usually do (still depends on how big/difficult the selecting though). Another way is to make a duplicate and experiment with it by using layer mask or layers to overlap then merge when finished.

On Tue, Feb 28, 2012 at 1:52 PM, mamboze wrote:

I've got a problem editing an image with a dotted background in it. By 'dotted', I mean an array of small evenly spaced black dots on a white background.

I've tried the fuzzy select tool which kind of works. It fills in the white space with the color I want but leaves the dots untouched. I want to get rid of the dots.

The image has a lot of rectangles containing text (these are not dotted) on this dotted background so using the select tool would be a real chore.

Any suggestions would be most welcome. Thanks

-- mamboze (via gimpusers.com)
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I've got a problem editing an image with a dotted background in it. By 'dotted', I mean an array of small evenly spaced black dots on a white background.

I've tried the fuzzy select tool which kind of works. It fills in the white space with the color I want but leaves the dots untouched. I want to get rid of the dots.

The image has a lot of rectangles containing text (these are not dotted) on this dotted background so using the select tool would be a real chore.

Any suggestions would be most welcome. Thanks

It very much depends on the image and the size of the dots.

The obvious is a mask of some sort but a quick solution might be

Filter -> generic -> dilate This shrinks everything by 1 pix around the perimeter.

if the dots still show, do it again. If it takes more that that, give up now.

then

Filter -> generic -> erode this add a pix around a perimeter, match this with the number of 'dilates'

If the the text or the box is small then chances are this will not work, you destroy what you want to keep.

On 02/28/2012 12:52 AM, mamboze wrote:

I've got a problem editing an image with a dotted background in it. By 'dotted', I mean an array of small evenly spaced black dots on a white background.

I've tried the fuzzy select tool which kind of works. It fills in the white space with the color I want but leaves the dots untouched. I want to get rid of the dots.

The image has a lot of rectangles containing text (these are not dotted) on this dotted background so using the select tool would be a real chore.

Hey Mamboze,

Try this:

* Make a new layer, fill it with your desired background color, and move it down so it is under your original image layer.

(This is done in the Layers tab of your dock window.)

* Select the original image layer, right click on it, and Add Layer Mask. Make the mask white - "full opacity".

* Open up your color selector (add set a light gray color - about 50% gray.

* Click on the layer mask to select it, then drag & drop to the main image window to fill the mask with gray.

* Back in the color selector, get some pure white selected.

* Turn on your rectangular select tool. Start using that to select your rectangles with text in the main image window, drag and drop to fill them with white.

(This will bring your rectangles back to their original appearance by restoring the mask's effect to 100% opacity in those areas.)

* All done? Use the "magic wand" or the "select by color" tool to select the gray in your layer mask.

* Back in the color selector, get some 100% black going, drag and drop to fill the selected gray area in your mask with black.

That will make your dots vanish entirely, leaving the layer below fully visible. You can use the select tools with drag and drop, or any of the painting tools, to correct any errors in your mask by adding white (make parts of the layer visible) or black (making parts of the layer invisible).

If you use the GIMP long enough, you will start to think of an image as a stack of layers, and using masks will (almost!) completely replace the "erase" tool.

Another neat thing to play with is to make a copy of a layer, apply a filter that you want to use on some but not all parts of the finished image, and make the altered layer transparent by adding a black layer mask. Then, painting in the image window with white will enable you to "paint the image with" the filter(s) you applied to the new layer.

:o)

Steve

Probably what I would have done is select-by-color one of the dots and then unselect any lines or whatever I wanted to save with the magic wand or the free-select tool. After that, I would have had all the dots (or most of the dots) selected and I could delete them or fill them as desired.

On Mon, Feb 27, 2012 at 11:52 PM, mamboze wrote:

I've got a problem editing an image with a dotted background in it. By 'dotted', I mean an array of small evenly spaced black dots on a white background.

I've tried the fuzzy select tool which kind of works. It fills in the white space with the color I want but leaves the dots untouched. I want to get rid of the dots.

The image has a lot of rectangles containing text (these are not dotted) on this dotted background so using the select tool would be a real chore.

Any suggestions would be most welcome. Thanks

-- mamboze (via gimpusers.com)
_______________________________________________ gimp-user-list mailing list
gimp-user-list@gnome.org
http://mail.gnome.org/mailman/listinfo/gimp-user-list

On 02/28/2012 06:52 AM, mamboze wrote:

I've got a problem editing an image with a dotted background in it. By 'dotted', I mean an array of small evenly spaced black dots on a white background.

I've tried the fuzzy select tool which kind of works. It fills in the white space with the color I want but leaves the dots untouched. I want to get rid of the dots.

The image has a lot of rectangles containing text (these are not dotted) on this dotted background so using the select tool would be a real chore.

Any suggestions would be most welcome. Thanks

Something that can work is to:

- make a selection on the background - grow the selection enough to make it swallow the dots (even if that bleeds over the text)
- then shrink the selection so that it gets out of the text (the dots will remain selected)
- then paint/erase the selection

Dots too close to the text will have to be erased by hand.

---
- ! "On Tue, 2012-02-28 at 06:52 +0100, mamboze wrote:\n> I've got a problem editing an image with a dotted background in it. By\n> 'dotted', I mean an array of small evenly spaced black dots on a white\n> background. \n\nThe most common cause for this is that it was a printed image that\nsomeone scanned, and the dots are what's called a screen.\n\nThere area number of descreening algorithms. Some scanners can do this\nfairly effectively.\n\nI often try scanning at 1200dpi or 1800dpi, then doing a gaussian blur\nwith a radius of between 11 and 19 pixels -- increase in the preview\nuntil you can't see the grid at all, then add a couple.\n\nThen afterwards scale the image down a lot, e.g. to 20% or even 10% of\nthe original scan, and use filters->enhance->sharpen.\n\nSelect the rectangles with text in them, and copy them to a separate\nlayer first, bcause they probably don't want blurring.\n\nLiam\n\n-- \nLiam Quin - XML Activity Lead, W3C, http://www.w3.org/People/Quin/\nPictures from old books: http://fromoldbooks.org/"

---
- ! "[sorry if you get this twice, sent from wrong account]\n\nOn Tue, 2012-02-28 at 06:52 +0100, mamboze wrote:\n> I've got a problem editing an image with a dotted background in it. By\n> 'dotted', I mean an array of small evenly spaced black dots on a white\n> background. \n\nThe most common cause for this is that it was a printed image that\nsomeone scanned, and the dots are what's called a screen.\n\nThere area number of descreening algorithms. Some scanners can do this\nfairly effectively.\n\nI often try scanning at 1200dpi or 1800dpi, then doing a gaussian blur\nwith a radius of between 11 and 19 pixels -- increase in the preview\nuntil you can't see the grid at all, then add a couple.\n\nThen afterwards scale the image down a lot, e.g. to 20% or even 10% of\nthe original scan, and use filters->enhance->sharpen.\n\nSelect the rectangles with text in them, and copy them to a separate\nlayer first, bcause they probably don't want blurring.\n\nLiam\n\n-- \nLiam Quin - XML Activity Lead, W3C, http://www.w3.org/People/Quin/\nPictures from old books: http://fromoldbooks.org/\n\n-- \nLiam Quin - XML Activity Lead, W3C, http://www.w3.org/People/Quin/\nPictures from old books: http://fromoldbooks.org/\nAnkh: irc.sorcery.net irc.gnome.org www.advogato.org"