Adding Rounded Corners to a Photo
Open a new photograph or image in Photoshop. I am using the picture of my dog Cracker:
The first thing you need to do is make the Background layer act like a regular layer. Double click the Background layer in the layer palette to bring up the New Layer dialog box. Type Photo in the Name text box and click the OK button.
Create a new layer button by clicking the new layer icon on the layers palette.
Fill this layer with white by selecting Edit then clicking Fill. Select white as the background color. Drag this layer to the bottom under the photoe.
Click back on the photo which appears on the top layer. Apply a layer mask by clicking the layer mask icon at the bottom of the layer palette.
You will not see anything happen yet. Your layer palette should now look like this:
Click again on the layer mask icon. This has applied a vector mask to the photo. Your layers palette should now look like this:
Both the layer mask thumbnail on the left and the vector mask thumbnail on the right look exactly the same, but there's a big difference between a layer mask and a vector mask. With a layer mask, you paint on it, usually with the Brush Tool, to make different parts of the mask either white, black, or some shade of gray in between. White makes that part of the layer visible, black hides it, and gray makes that area partially visible depending on how light or dark the shade of gray is. Vector masks, on the other hand, don't require any painting. In fact, you can't paint on them because Photoshop won't let you. Instead, you use shapes to control which parts of the layer are visible or hidden. In fact, you're going to use a shape right now to create our rounded corners!
Select the Rounded Rectangle Tool from the Tools panel.
Select any solid color for your Rounded Rectangle by clicking once on the Foreground Color selector in the Tools window. The color will not matter because we are going to eventually delete the shape. Ensure that the Background Color is white.
Change the Radius value of your rounded rectangle to 40 px.
Click on the vector mask thumbnail to select it.
Draw a rounded rectangle onto the canvas. If you need to reposition your shape as you're dragging, hold down your spacebar, then drag the shape into its new location. Release the spacebar when you're done and continue dragging out the shape.