I have used Gimp a bit in the past but have decided to adopt it as my main image editing software.

One of my most frequently performed tasks in Photoshop is removing the white background from pure black-and-white grayscales by dragging the gray channel onto the dotted circle option in the channel menu (sorry, away from my laptop at the moment so can't be more precise) which selects all the white pixels allowing me to delete the white pixels in one fell swoop.

Is there an equivalent workflow in Gimp? Thanks!

The post is not specifically about GIMP but rather about the general concept of rendering digital images for display on a computer monitor.  It is provoked by an observation triggered by Windows Photo Viewer (WPV) and pertains to the problem of obtaining a consistent result when viewing a digital image which I think is the main objective of GIMP.  In that, GIMP is producing something that needs to be useful with all manner of hardware and software.

In this case we're specifically talking about viewing a digital image on a computer display monitor but I would think the same problem exists with all manner of other devices used to display graphical images.  My recent interest in learning about digital image editing has lead me to learn that color management is a pretty complex subject and that differences exist between all of the devices involved in the process (i.e., work flow) of creating an image.  I also recognize that there is an inherent problem in trying to produce an image whose only purpose is to be viewed but that we don't have any control over what devices our audience might want to use when viewing that image.  However, it is really troubling when a fully developed image looks dramatically different when viewed on the same device using different software.

I offer as an example a photograph in the form of a jpg image developed by a camera.  Since I also realize that you will be viewing anything I can try and show you with equipment and software unknown to me, the only way I could think to accomplish my objective was to photograph my own monitor while displaying an image.  Keep in mind that image quality is irrelevant in this case the only thing I'm wanting to demonstrate is difference, which I'm thinking should be apparent no matter how you are viewing this image.

Here is a photograph of a photograph being display on my monitor with 2 different image viewers.  In that, the exact same file has been opened by each viewer.  The one on the left is the WPV that is part of Windows 7 and the one on the right is GIMP.  It looks to me like WPV is the outlier.  In that, whatever differences might exist between other viewers (i.e., other than these 2) are subtle enough that they are not so apparent, at least to me, from what GIMP shows.  However, I'm inclined to think that whatever explanation might exist for the difference demonstrated here could also apply to any software and that all such software may in fact be different in the same respect even if those differences are not sufficiently dramatic to be apparent to me or maybe even to you.  It would be much more comforting to learn that WPV is an anomaly and that by simply not using it this apparent problem is solved.

Can anyone explain what is happening here?

When I scale down and rotate layers in 2.9.8/9, resolution is decreased and layer is blurred.  I remember this wasn't like that before.
 
Is that a bug?

What can I do get GIMP to load faster? It loads very slowly, mostly with the finding fonts window.

I input specific size and position quantities for the crop tool, and I saved that preset. Well, the preset loads just fine, but when I go to crop, I have to press the preset 4 times for it to adjust properly! Ideally, I'd like to just have to press 1 button after I load the preset. Is there a way to get this to work more efficiently?

20 second clip demo'ing the problem: https://www.dropbox.com/s/8phycw6rdry9vv...2.mp4?dl=0

Greetings!

I am absolute new to GIMP (and any other than MS Paint...)
My problem is:
I have 6 pieces .bmp images of same size
Rotate them 180°
then combine them into a 3x2 format and save the result.
(or combine in reverse order, then rotate the result 180°)

It's not a big deal in paint, but I have a few thousands of those sixpacks, and I would like to automate the process.

I'm using Windows and quite familiar with windows batch, therefore when I heard that Gimp has powerful command line features I was happy.
But honestly, after half a day of searching forums and looking trough procedure browser, I did not get closer to the solution.
I dont even know where to start.
I can insert images to multiple layers, but cannot move them.
Is there a simple "move"-like command, or I have to write a complete plugin for this?

Please, if this is not some incredible hard task, help me with with a little starting kick.

[Hi! Sorry for bad english!]
(yes, I heard about ImageMagick, but I work on a company PC and can use only whitelisted softwares. While GIMP is accepted, IM isn't.)

I have coloured in the background of an image black, and exported it. all was fine until i opened it again and now all the black bits are transparent, and I can't figure out how to get it back to normal, please help!

i have attached a section of the affected image

Attached Files

Image(s)
   

This is a thread for the elite users.

Short story, I want to either fix the pan viewing on my Turcom 6610 tablet or have gimp treat the mouse and tablet as the same tool set.

I am running Gimp 2.8 on Windows 10.

I currently have an interesting situation where certain projects treat my tablet and mouse differently.  It used to be that my tablet and mouse (as I think it's supposed to) were being treated as different tool sets, and the tablet would have issues with the pan viewing where when I clicked the space bar, the window view would bounce a little and not pan where my cursor originally was. 

Over the last few weeks, I have been using this one file that I made which treats my mouse and tablet as the same toolset.  I have to click off the main canvas to switch between tablet and mouse, but it keeps me on the same toolset and it fixed the pan viewing on my tablet.  

My issue now is that I cannot recreate what I did with this file in order to have the mouse and tablet be the same toolset.  I can copy the file and the single toolset works in the copy, but I cannot create a new file from scratch and keep my single toolset function.  the new files also brings back the tablet pan viewing issues.  

Everything else from what I can tell works just fine between mouse and tablet.  Pressure sensitivity and mapping looks correct.  Drivers should be updated.  Any help or input would be appreciated.

Thank you! 

Okay so this happened out of the blue. Normally when I copy and paste something with an alpha background, the alpha part is clear so my background color only shows. Now for some reason it posts as black. I know most people will tell me to just set the black to the alpha color but this also messes up images that are already black and the alpha color change doesn't recognize. I didn't have this issue till today out of the blue and I didn't mess with any settings. This is what the image looks like online
   
this is how it looks when I copy and paste it.
   

Editing in a photo is fraught with peril, in the good cases the subject looks weird, in the bad case s/he looks dead. But using the camera flash often makes it necessary to edit the picture to fix these awful red eyes, which is why I tried with much interest a technique alluded to on Pixls.us, for a new RawTherapee plugin:

Quote:

1. compute the average of the G and B tones
   
2. if the R tone is 1.5 times greater than that average, replace the R with the GB average value.
   

1. Make a selection on the eyes. It can/ should include the iris, but avoid skin tones. Feather a bit
   
2. Make a new layer from that: Ctrl-C, Ctr-V, Ctrl-Shift N. Let's call it "Eyes".
   
3. Make a copy of "Eyes", call it "Red 75%", start Color>Component>Channel mixer, set to "Monochrome", set Red to 75%, and Green and Blue to 0
   
4. Make a second copy of Eyes, call if G+B/2, start Color>Component>Channel mixer, set to "Monochrome", set Red to 0%, and Green and Blue to 50%
   
5. Make sure that all layers are invisible except these last two, with "G+B/2" over "Red 75%" and set G+B/2 to "Grain extract". The result should be eyes with a white disk where the red pupil was (with a dark spot where the white spot is).
   
6. Open the Channels list, and drag one of the R, G or B channels to the "main" list to copy it.
   
7. Back to the Layers list, make a last copy of "Eyes", call it "Correction", start Color>Component>Channel mixer, reset "Monochrome", set the Red channel to R=0%, G=50%, B=50%.
   
8. Make all layers invisible except the original picture and "Correction"
   
9. Right-click "Correction", and "Layer>Add layer mask". Initialize to "Channel" and pick the channel you copied at step 6. You should now have a fixed image.
   
10. At that point, you are editing the layer mask of "Correction" so you can tweak the amount of correction by playing with Levels or Curves (the most radical being thresholding the mask around 200, but this can make the fix limits a bit more visible).