1. Open the GIMP program and select the image you want to work with. In the top menu bar click:
FILE → OPEN then find image in your files
2. After your image opens up, in top menu bar click: LAYER → DUPLICATE LAYER
3. In your layer dialog box you want to make sure that your top(copy) is highlighted, that is the layer we will be working with. We need to make the top layer black and white, leaving the bottom layer color. In the top menu bar click COLORS → HUE-SATURATION Turn the saturation slide bar all the way down, your image should now be black and white.
4. Now, in top menu bar LAYER → TRANSPARENCY → ADD ALPHA CHANNEL
5. You are going to erase the part of the photo that you want to be color. When you erase the black and white, the color layer under will be shown. Select the pink eraser from the toolbox and select the solid circle brush. You can adjust the size of your brush depending on the size of the area you want to erase. If you make a mistake, click EDIT→UNDO
6. The last step is to export your new image to your computer FILE → EXPORT. Name your new image and select the type of file you want it to be saved as(.JPEG)
Click HERE to see Halloween pictures with fun backgrounds. Follow the same steps here except open your background first, then resize image to the same size of your photo. After that, all you have to do is drag and drop your photo on top. Now just pick up at step #4 and you will be erasing the background of your photo to reveal the background beneath.
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