This tutorial will teach you how to separate pieces of an image from their background, "cutting them out" so to speak, through editing. The background will be made transparent, and whatever aspect of the photo you separate will be applicable just about anywhere.
- GIMP (which is free to download)
- A physical mouse if you have a laptop and don't want to paint using the touch pad
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Step 1: Load the Image
Load the desired picture into GIMP by going to File → Open as layers
Step 2: Select Color Rendering (Optional)
Select “Absolute Colorimetric” if prompted with the “Convert to RGB” window, then click “Convert.”
If the menu doesn't appear, the image will be loaded as a layer, and you can continue to step 3.
Step 3: Add an Alpha Channel
From the top menu bar go to Layer →Transparency and select “Add alpha channel.” This makes the default background transparent, which will help later.
Step 4: Add a Layer Mask
Go up to the top selection bar and go to Layer → Mask → Add layer mask. It should be set to “White (full opacity).”
Step 5: Paint in the Mask
Use the paintbrush tool, and make sure the color is set to black. Then with the mask selected, paint on the image around whatever you want to separate from the background.
Tip: If you make a mistake, switch the color you're painting with to white and go back over the area you messed up on. This will bring back the part of the image you erased.
Step 6: Transparency Shows Through
While painting you should see grey and white squares begin to show through, this is the transparent background showing up, and it means you’ve done everything right so far.
Tip: You can use the [ and ] keys to adjust brush size.
Step 7: Export the Image
When you’re satisfied with the masking job, move to the menu bar and select File → Export as, and select your desired save location.
Step 8: Change the File Type
Change the file type from .JPG to .PNG, which you can do by just typing in the bar that contains the file name.
Step 9: Export the Image Part 2
Here you can decide which values of the GIMP creation you want to keep. Make sure the boxes for "Save Resolution" and "Save Background Color" are checked, and I would recommend keeping the "Exif Data" as well. They should be checked by default, but it's good to make sure.
Then just click “Export" when you've done all that.
Tip: You can ignore the compression slider in the window since it's a .PNG.
Step 10: Open the Saved File in Another Program
If all the steps were done correctly, you should be able to open the file in another program and see that the part you painted around is what's still visible, while the rest is transparent.
And that's it, you're done! You can repeat the steps on as many images as you need to.