While browsing through some photoshop tutorials, I came across 'Lomo Effect'. There seem to be lot of Photoshop tutorials to add lomo effect to your pictures, so I thought to write one for GIMP.
I used GIMP 2.6.2
image resolution 1024x768
1] Open your image in GIMP.
2] Select whole photo using 'Select | All'
3] Shrink the selection by 75 pixels (Select | Shrink)
4] Feather the selection by 300 pixels (Select | Feather)
5] Invert the selection (Select | Invert)
6] Create a new transparent layer and select it
7] Take the gradient tool, set shape to 'Radial', and add a white to black gradient from center of phot to the bottom side. You must get something like this:
8] Set the gradient layer mode to overlay.
9] If the border looks too dark, reduce the opacity of the gradient layer or ifs less dark then duplicat the gradient layer (make sure the duplicate layer is also set to overlay mode). I got the following result after duplicating the layer.
10] Flatten the image (Image | Flatten Image)
11] Open the Color curves dialog (Colors | Curves), set channel to values and apply an 'S' curve, something like this:
12] Apply the changes.