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11-08-2018, 09:08 AM
(This post was last modified: 11-08-2018, 09:12 AM by Espermaschine.)
I think i can reproduce the phenomena. Used a Threshold of 112 and apparently clicked on a grey that was close enough to the white. Got this:
The problem with this image is that its either bad quality and all the variation in grey are artifacts or this is watercolour with different concentration of pigments.
Not really a good image to start with.
It shouldnt be too difficult to reproduce a random dot pattern from scratch (with a brush dynamic for example).
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(11-08-2018, 09:08 AM)Espermaschine Wrote: I think i can reproduce the phenomena. Used a Threshold of 112 and apparently clicked on a grey that was close enough to the white. Got this:
The problem with this image is that its either bad quality and all the variation in grey are artifacts or this is watercolour with different concentration of pigments.
Not really a good image to start with.
It shouldnt be too difficult to reproduce a random dot pattern from scratch (with a brush dynamic for example).
You got the same thing! Is this tinting of the white spots a bug, or feature, LOL? Can it be circumvented, some way other than selecting color and inverting, for that majority of images that have more than 2 colors?
Is a brush dynamic something that can be described in words of one syllable?
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Quote:.Is this tinting of the white spots a bug, or feature, LOL? Can it be circumvented, some way other than selecting color and inverting, for that majority of images that have more than 2 colors?
Nothing to do with Gimp. It is the poor base image you are using.
Bucket Fill with 'Fill similar colours'
1. Depends on where you click in the image and
2. The threshold value.
Reduce the threshold gets a better white but risks not including all of the mottled grey. See my earlier screenshot.
Learn to be flexible, not all procedures are suitable for all images. Use the Select -> Invert -> Fill procedure.
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(11-08-2018, 10:14 AM)rich2005 Wrote: Quote:.Is this tinting of the white spots a bug, or feature, LOL? Can it be circumvented, some way other than selecting color and inverting, for that majority of images that have more than 2 colors?
Nothing to do with Gimp. It is the poor base image you are using.
Bucket Fill with 'Fill similar colours'
1. Depends on where you click in the image and
2. The threshold value.
Reduce the threshold gets a better white but risks not including all of the mottled grey. See my earlier screenshot.
Learn to be flexible, not all procedures are suitable for all images. Use the Select -> Invert -> Fill procedure.
The Select -> Invert -> Fill procedure is not unknown to me; I have used it many times. The question I’m asking in this thread is how to circumvent this problem in general, when there are 100 colors in an image… can you offer any insight there? :-)
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(11-08-2018, 11:48 AM)HavingTooMuchFun Wrote: ....The question I’m asking in this thread is how to circumvent this problem in general, when there are 100 colors in an image… can you offer any insight there? :-
Certainly can. Do not use bucket fill.
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(11-08-2018, 11:54 AM)rich2005 Wrote: (11-08-2018, 11:48 AM)HavingTooMuchFun Wrote: ....The question I’m asking in this thread is how to circumvent this problem in general, when there are 100 colors in an image… can you offer any insight there? :-
Certainly can. Do not use bucket fill.
What should I use instead?
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(11-08-2018, 08:49 AM)HavingTooMuchFun Wrote: (11-08-2018, 07:33 AM)Ofnuts Wrote: In your screenshot the Foreground color in the toolbox swashes (a neutral gray) isn't the one that appears to have been used to bucket-fill...
Can we start again from scratch, with the original image, the actual FG color. You can also attach the before and after images (as XCF)?
My before and after images are available in my first post. The toolbox settings would be the same, because I never touch them, other than the threshold that I didn’t record the exact # for and so can’t duplicate, and of course the little square showing a different foreground color. :-)
The bucket fill shouldn’t be tinting an entire image EVER, right, regardless of what threshold or foreground color I pick? Based on every article I’ve read, it should either be filling or not filling; I haven’t been able to find any other examples of Gimp behaving this way.
Yes, and we can't reproduce the problem either. I can see a way to have you result but this would be using separate selection plus bucket-full selection: if the color-selection step has "feather edges" enabled, then the selection would be partial over the dots and this would tint them.
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11-09-2018, 02:36 AM
(This post was last modified: 11-09-2018, 08:19 AM by rich2005.
Edit Reason: fix text formatting
)
(11-08-2018, 01:32 PM)Ofnuts Wrote: (11-08-2018, 08:49 AM)HavingTooMuchFun Wrote: (11-08-2018, 07:33 AM)Ofnuts Wrote: In your screenshot the Foreground color in the toolbox swashes (a neutral gray) isn't the one that appears to have been used to bucket-fill...
Can we start again from scratch, with the original image, the actual FG color. You can also attach the before and after images (as XCF)?
My before and after images are available in my first post. The toolbox settings would be the same, because I never touch them, other than the threshold that I didn’t record the exact # for and so can’t duplicate, and of course the little square showing a different foreground color. :-)
The bucket fill shouldn’t be tinting an entire image EVER, right, regardless of what threshold or foreground color I pick? Based on every article I’ve read, it should either be filling or not filling; I haven’t been able to find any other examples of Gimp behaving this way.
Yes, and we can't reproduce the problem either. I can see a way to have you result but this would be using separate selection plus bucket-full selection: if the color-selection step has "feather edges" enabled, then the selection would be partial over the dots and this would tint them.
Espermaschine in comment #11 reproduced the problem, so it’s not just me…? I wouldn’t even know how to do the double-selection process you described, and that’s not what I did here… and the dots aren't just partially covered, they are totally covered, and every other time I’ve seen this happen, it has been 100% of the image that has been tinted. Do you have any idea what Rich was suggesting that I use instead of bucket fill to circumvent this problem?
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Quote:..Espermaschine in comment #11 reproduced the problem, so it’s not just me…?
What he actually said
Quote:I think i can reproduce the phenomena. Used a Threshold of 112 and apparently clicked on a grey that was close enough to the white.....followed by .....The problem with this image is that its either bad quality and all the variation in grey are artefacts
In a nutshell, garbage in ...garbage out
With that variation of mottled grey (looks like horrible jpeg artefacts) and the high threshold the bucket fill spreads to the white dots.
Max the threshold and it fills the whole image, as you would expect.
Use a lower threshold and white remains but so does some of the grey spectrum, as you would expect.
Quote:Do you have any idea what Rich was suggesting that I use instead of bucket fill to circumvent this problem?
Do not get fixated on using the same procedure (a straight bucket fill) for every image. You have been told the best procedure is constrain the area for the fill by using a selection.
There are always other ways, but not necessarily the most universal or the best. What might work for that particular image but not for all images.
1. A small Gaussian blur, followed by a bucket fill with a smaller threshold that you are using now. https://i.imgur.com/gHNO5Hv.jpg
2. Duplicate layer, Colour to Alpha, New from visible, followed by a bucket fill with a smaller threshold that you are using now. https://i.imgur.com/yTjN4Va.jpg
3....and so on, mode to indexed and edit the colormap, image with a layer mask, over a coloured layer...all sorts of ways.
The idea being, none are as easy as Select the white dots, Invert the selection, Fill.
This thread has become pointless. An exercise in Does not work the way I think so must be broken.
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You know, Rich, if dealing with beginners makes you angry and frustrated, the simple solution to that would be to not comment on the thread of anyone who is too far below your level of expertise, lol.
Since bucket fill is supposed to either fill or not fill, and not tint anything, technically it is IS “broken,” at least for some cases; it’s useful to know that it is likely to fail with a lower quality image.
Thank you for the list of alternative methods! I don’t have any idea what you’re talking about, of course, but I’m going to hold on to it in the hopes that I will eventually be able to do those things. :-)
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