A round picture?! This theory resembles that of how to make a square from a circle (or rather, how to make a circle from a square shape), i.e., quite impossible. Photo viewing softwares can handle square shapes exclusively, but with some tricks, you can deceive the spectator, at least, with a round photo, use transparent background for instance, which can look great on websites.
Load the photo in Photoshop
You can turn any regular photo into a round-shaped one if you think it cries out for that shape. We would like to cut out the main theme in the sample picture and turn it into an elliptic shape and then use it for a webpage.
Before setting about selecting, the existing Background layer has to be made modifiable. To do so, just double-click Layers palette, and click OK in the appearing window. Nothing happens, only the Background layer changes to Layer 0, which is now editable.
Edges of the photo
To select the oval shape, choose Elliptical Marque tool (M key). If it’s not active, click on the second icon on the tools palette, keep it pressed, and choose elliptical marque (second icon) in the appearing menu.
Define one corner point for the selection, then keep the left mouse button pressed and select the desirable area. If you aim for a regular circle, keep Shift key pressed during selection. The circle line can be moved with the arrow keys.
The edges are needless
In case you wouldn’t like to have sharp edges but softer, transitional ones, right-click within the selection’s outline, and then in the menu choose Feather option. You can set anything for the value of Radius depending on the pixel-width of the blur in edges you desire. Blurring is not compulsory, of course. You can leave the sharp edges, too. In that case omit this paragraph.
If you are ready or want sharp edges, right-click within the selection area and choose Select Inverse. We selected the picture part that we wish to keep and now we have changed the selection to its inverse in order to get rid of the needless parts.
After selecting the edges just push the Delete button o the keyboard and they will be deleted.
Cut to narrow
There might be needless, empty parts left around the round area, which can be easily removed with a quick trimming. Choose Image/Trim option and the settings shown in the photo above, then click OK. The needless parts will be gone.
Save the photo with File/Save For Web & Devices menu.
Two image types are able to handle transparency, which are later apt for the web. One is GIF and the other one is PNG. The former is smaller in size but can be 8 bits maximum, and so it is quite a poor quality. If you wish the preserve the original colors and features of the round photo, you’ll have to opt for the 24-bit PNG. This means a big file size, which is not ideal for the web, so you should use this method in smaller pictures only.
So, at the top of the saving window choose PNG24 option, and check if Transparency below it is selected. Then just click the Save button.
The saved round picture is now ready for the internet, where it will appear in its original form, keeping the transitional edges as well.