I had cut the background out of an image, with the person in the foreground, and wanted a background that mimicked the SLR view of a low f-stop, where the foreground is sharp but background is blurred.
To do this in Gimp is interesting. I found an image with a very sharp background.
Here are the steps:
This skill is useful as you can take pics of your friends and place them in different places that they have never been! There are a couple of tricks to make your work easier and results look better. I’ve written some notes to accompany this video, but there’s also 2, 3, 4, 5, 6
Import the image, add transparency
Once you import an image it will not have transparency. For this you will need to highlight the layer, colors-> transparency -> add alpha channel. You will notice that the layer name goes from bold to not bold. Duplicate the layer, just in case of a mistake.