When I resize images in Photoshop, I do the scaling from the corners while I press Shift to maintain the proportionality of the important elements in my images, like people, animals, etc. But what if the image is to be resized to fill up spaces horizontally/vertically? Resizing images from the corners would change both the height and width and so you still have to crop the image. This is where content-aware scaling comes in. This feature is available on Photoshop CS4 and also on CS5.
Below is a screenshot of my subject photo. You’ll notice that I already increased the canvas size to show the target size of the image after editing it. Next to it is the resized image using the Free Transform tool. The surfer and his board were stretched horizontally too.
I’ll revert back to the original image to resize the image again using the Content-Aware Scale tool – first, by using the Protect Skin Tones option.
With the image in its original dimensions, click Edit > Content-Aware Scale or you may press CTRL + Shift + Alt + C as a keyboard shortcut. Handles will appear on your image just like when you’re using the Free Transform tool. On the top just below the main menu, you’ll find the Protect Skin Tones icon. If you toggle this on, Photoshop will try to protect regions that contain skin tones.
Here’s how it looked like after I did a content-aware scale with skin tone protection. Notice that the surfer’s details are preserved while the surf board is stretched a bit. This is how the Protect Skin Tones option works. Photoshop bases its scaling on the images skin tones.
I’ll revert the image back to its original form to content-aware scale by creating an alpha channel. First, I’ll select the surfer and surfboard using the Lasso tool (you may use any tool when doing a selection). It doesn’t have to be a perfect, just as long as the subjects are inside the selection. See image below.
After making the selection, click Select > Save Selection… and give it a name, e.g. “surf”. Press CTRL + D to deselect. Fire up the Content-Aware Scale tool. Check the Protect section again, this time from the drop down menu, select your saved channel.
After selecting the channel, resize your image. Press Enter to apply the transformation. Below is the image where all the important elements were preserved.
There are other things that you can do with Content-Aware Scale like moving objects closer together or far away from each other. Try it out and check if you find any other applications of this tool.
For questions, you may email me at . A downloaded PDF is also available at Scribd.