Re: [Gimp-user] dotted areas, how to erase (or change)
[sorry if you get this twice, sent from wrong account] On Tue, 2012-02-28 at 06:52 +0100, 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. The most common cause for this is that it was a printed image that someone scanned, and the dots are what's called a screen. There area number of descreening algorithms. Some scanners can do this fairly effectively. I often try scanning at 1200dpi or 1800dpi, then doing a gaussian blur with a radius of between 11 and 19 pixels -- increase in the preview until you can't see the grid at all, then add a couple. Then afterwards scale the image down a lot, e.g. to 20% or even 10% of the original scan, and use filters->enhance->sharpen. Select the rectangles with text in them, and copy them to a separate layer first, bcause they probably don't want blurring. Liam -- Liam Quin - XML Activity Lead, W3C, http://www.w3.org/People/Quin/ Pictures from old books: http://fromoldbooks.org/ -- Liam Quin - XML Activity Lead, W3C, http://www.w3.org/People/Quin/ Pictures from old books: http://fromoldbooks.org/ Ankh: irc.sorcery.net irc.gnome.org www.advogato.org ___ gimp-user-list mailing list gimp-user-list@gnome.org http://mail.gnome.org/mailman/listinfo/gimp-user-list
[Gimp-user] dotted areas, how to erase (or change)
Hi Steve, Thanks for the help and sorry for the delay in responding. I'll run thru your suggestion today. Roy >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 -- mamboze (via gimpusers.com) ___ gimp-user-list mailing list gimp-user-list@gnome.org http://mail.gnome.org/mailman/listinfo/gimp-user-list
Re: [Gimp-user] dotted areas, how to erase (or change)
On 02/29/2012 05:35 AM, mamboze wrote: > thanks to all for your help, it's very much appreciated. > > @Steve, > > I trying following your instructions but I'm stuck at this step > >> * Click on the layer mask to select it, then drag & drop to the main >> image window to fill the mask with gray. > When I drag and drop, this makes a new layer but no gray. Is this right? > > I would very much like to work thru this. It looks like a good technique to > know. > Hey manboze, My bad. I should have said, "Click on the layer mask thumbnail in the Layers dialog to select it, THEN drag and drop from the Foreground/Background tool (a.k.a. main color tool) to the main image window." The object is to turn the mask gray. That will make the layer you are working on semi-transparent. Adding white to the mask will make those parts of the layer fully opaque, adding black to the mask will make those areas fully transparent. This seems like a good time to plug Akkana Peck's book, "Beginning GIMP: From Novice to Professional" http://gimpbook.com/ It's one of the best software user textbooks I have ever seen and surprisingly inexpensive. :o) Steve ___ gimp-user-list mailing list gimp-user-list@gnome.org http://mail.gnome.org/mailman/listinfo/gimp-user-list
[Gimp-user] dotted areas, how to erase (or change)
thanks to all for your help, it's very much appreciated. @Steve, I trying following your instructions but I'm stuck at this step >* Click on the layer mask to select it, then drag & drop to the main >image window to fill the mask with gray. When I drag and drop, this makes a new layer but no gray. Is this right? I would very much like to work thru this. It looks like a good technique to know. -- Roy (via gimpusers.com) ___ gimp-user-list mailing list gimp-user-list@gnome.org http://mail.gnome.org/mailman/listinfo/gimp-user-list
[Gimp-user] dotted areas, how to erase (or change)
Thanks to all for your suggestions. I've obviously on a learning curve here, but all this help will make it that much easier. The layers and mask suggestion looks very interesting (and powerful). Actually, I'm going to work thru all the suggestions as exercises. Thanks again -- mamboze (via gimpusers.com) ___ gimp-user-list mailing list gimp-user-list@gnome.org http://mail.gnome.org/mailman/listinfo/gimp-user-list
Re: [Gimp-user] dotted areas, how to erase (or change)
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. ___ gimp-user-list mailing list gimp-user-list@gnome.org http://mail.gnome.org/mailman/listinfo/gimp-user-list
Re: [Gimp-user] dotted areas, how to erase (or change)
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 ___ gimp-user-list mailing list gimp-user-list@gnome.org http://mail.gnome.org/mailman/listinfo/gimp-user-list
[Gimp-user] dotted areas, how to erase (or change)
>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. -- rich (via gimpusers.com) ___ gimp-user-list mailing list gimp-user-list@gnome.org http://mail.gnome.org/mailman/listinfo/gimp-user-list
[Gimp-user] dotted areas, how to erase (or change)
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
