1. Open Photoshop. Open the image to apply uneven edge border.
2. Select Rounded Corner Tool from the toolbox (marked red in the fig.).
3. Keep "Paths" option selected as shown in the fig (marked in green).
4. Drag the rounded corner rectangle in the middle of the image as shown the the picture.
5. Go to Path Tab and click "Load path as a selection" to convert the path into selection.
6. Go to Channels tab. Create new channel. Fill white color and deselect the selection with CTRL+ D.
7. Filters > Brush Strokes
8. Go to Layers Tab and create new layer. Keep the new layer selected.
9. Select > Load Selection (Select Alpha1 from channel drop down and check Invert)
10. Fill white color using Alt + Del. and deselect with CTRL + D.