How do i erase blue pencil lines from a black and white drawing?

Do they stack? For example I am doing a Color Select and it is working perfectly but I do not want it to select the color throughout the entire image. I only want to select the color on a  piece of the image. I tried using Rectangle Select to select the portion of the image that I am interested in and then I tried to use Color Select just in the previously selected area but instead the color was selected throughout the image.

I tried using Select Fuzzy but that still selected too much of the image. There must be a way to have Select Color look for the selected color in just a part of the image.

For example in the image below I want to turn the blocks of green that form a ( and turn them blank. I have gotten SO CLOSE but either a bit too much or a bit too little gets selected.  

   

Here is my best attempt but too much of the blocks remain. 
   
Here too much of the image is removed.
   
It would be nice to have the Select Color tool just look at a small area surrounding the blocks. 
 
Thanks

I have always used an older version of gimp like 2.8 or something like that i just upgraded to 2.10.36. now this is my problem i make clothes for sims and i always used the bump map when doing this in 2.8...I did this by adding a new transparent layer putting the creases in white on that layer and then go to where i want the creases to be on the main colored layer and opening up bump map and clicking on the crease layer so it would bump map it to the colored layer. pretty easy and straight forward now my problem is i go to do that in the new gimp and i get nada nothing ect, i have looked for tutorials that explain how to do this but find none. can anyone help ty in advance

Hello everyone. I need some assistance with getting the Gimp help file to work properly. I tried doing a search for appimage + help file and appimage + user manual and several other variations of this and didn't get any board hits.

I'm using the Gimp AppImage by TasMania17 here:

gimp2-10-36-python2-mm-ubuntu.AppImage

along with Linux Mint 21.3.


Neither the "use the online version" or "use a locally installed copy" of the help system work properly. I would prefer to utilize the "use a locally installed copy" offline option if possible.  I have a .pdf copy of the help file/user manual, which is okay, but it's not integrated into Gimp and is a hassle to pull up each time I need it.

Trying on my own to get things working properly, I installed gimp-help-en 2.10.0-1 from Linux Mint's Software Manager.  I knew it likely would not work, but did manage to get the 57.3 mb  folder of .html files that was installed and saved it in case I could use that in some way.

I also downloaded the gimp-help-2.10.34 .tar file from docs.gimp.org, but really don't know what to do with it.  I've never been too adept with tarball archive files. 

Is it possible to get the integrated help file system to work properly with an appimage?

Hi. I want to make this image transparent: https://imgur.com/a/7z7WtzU

So it looks like this example: https://imgur.com/a/R0I8Z6M

I believe the way to do this is the use color to alpha but it doesn't give the desired result I want.

Anyone know how?

Monash University (the institution I work at as a neuroscientist) decided to no longer provide academic researchers (staff and students) with Adobe Creative cloud (essential things like Illustrator and Adobe DC Pro) because they're "too expensive" for the budget. Staff and students are required to purchase said software out of their own wage. Meanwhile, the Vice Chancellor (on AUD 1.3 mil/year) was given a going away party, which cost  AUD 147,000. 

Alas, I need to re-learn how to do all my skills again on free alternatives (i.e., Inkscape and GIMP).

I need to know how to select a colour channel, add a layer mask to remove the background, and then change the colour of a neural spike trace response. here is what it should look like (see images):

Hi there, newbie here.
I am a very basic user, doing simple, repetitive tasks, which typically involve cropping an image to a rectangular aspect ratio of 1.308:1 but to different pixel sizes. The online service the pictures are intended for has a maximum file size of 187kb per image, so I then scale my images, which are of different file sizes (so I can't use a default percentage scale), possibly 2 or 3 times until it is just under 187kb. 
Is there an easier way to scale my cropped image to a fixed file size?
Many thanks,
Jules.

If you have lots of LUTs and you want to have a preview, then you can use this free program. Make a small crop or downsize a big photo if you want a fast preview.  

https://sourceforge.net/projects/bulk-luts-previewer/

   

Hello, i downloaded a PBR from the internet. but i want to change the color. in the description of the product it's said it can be done by adding a mask in the composite layers. idk how to do this, and i can rely on GIMP only, as i don't own photoshop. and paint.net doesn't do the trick. so is it possible to do this in GIMP, if yes how? here's the exact descriiption of the pbr so you have a better idea

Material of old painted boards. The color is green by default, it can be changed in Composite Layers using a mask (disabled by default and also not available in FBX)

Thank you

Hello again everyone!

I used a colorization affect in BIMP to change 16 of these gauge parts from this 

     

to this 
   

which is exactly what I wanted.

But now the difference between the 2 colors on the new circle part are not different enough to stand out well.

How can I batch alter just one of the 2 colors?

Thanks