Adobe uses graphics chip for faster Photoshop CS4

Photoshop is a famously taxing piece of software, but beginning with the upcoming CS4 version, it'll be able to employ the muscle of your computer's graphics chip for the first time.

The new version of Adobe's flagship software product takes its first steps in using the graphics processing unit, or GPU, said John Nack, principal product manager for Adobe Photoshop. For example, the graphics chip helps Photoshop CS4 fluidly zoom in and out, rotate the canvas so artists can reorient an image for the best sketching angle, display and manipulate 3D objects, and handle color correction.

"It's not lost on us that when you look at the rate of GPU power advancement, there's an enormous wealth of cycles we can take advantage of now," Nack said. "The rate of price drop and performance gain has been off the charts."

Using graphics chips opens up new horizons, but it poses its challenges. For one thing, graphics chips are designed to blast pixels to the screen, not back to the main processor for further work, so not all tasks can be accelerated, he said. For another, it means Adobe has to work more carefully on hardware compatibility and means some people with older machines might have to upgrade at least the video card; he recommends a card with 128MB of memory.

"Typically, when folks were building a big Photoshop rig...we never had to really concern ourselves with things like which video driver they were using. We had a very light integration. Anything was fine," Nack said. "Now that we're doing actual processing on the GPU, we have to be a good deal more stringent."

Another new GPU-enabled feature is called Pixel Bender, which lets people apply special effects quickly and, Adobe promises, create their own effects more easily than with today's filter technology. However, that missed the cut for the final version of CS4 and likely will be a free update at the Adobe Labs site, Nack said

The upgrade price for Photoshop is $199 for the Photoshop CS4 and $349 for CS4 Extended; prices for the new versions are $699 and $999. The Extended version adds a variety of special-purpose abilities for dealing with scientific applications, dealing with medical imagery, and creating 3D subject matter. The company also offers its consumer-level Photoshop Elements for about $100 and its online Photoshop Express for free.

The software will be available in October, the company said.

Now with 64-bit support
Another hardware change--for Windows users only--is support for 64-bit processors. Most folks won't notice much of a speedup--perhaps 10 percent in some cases--but performance is much better in some memory-intensive areas where the 4GB limit of 32-bit software is a problem.

"For most people, with a 12-megapixel SLR file or doing Web design work, the difference they'll see is pretty negligible. The inflection point from 32-bit to 64-bit really happens where you would have run out of memory and would have had to go to your virtual memory system," storing data on the hard drive rather than in memory, Nack said. "There's a tenfold performance increase opening up a large file."

A companion product geared specifically for photographers, Photoshop Lightroom, has 64-bit support for both Mac and Windows, but Adobe couldn't do the 64-bit version of Photoshop CS4 for Mac OS X because it was busy moving to a new underlying programming foundation from Apple, called Cocoa.

Photoshop, meet Macromedia
Adobe's acquisition of Macromedia gave the company access to the Flash technology for animation and scripting, and Photoshop CS4 now employs it in the plumbing. In the past, it was tough for third-party software developers to add new features to Photoshop, but built-in Flash 10 software means Photoshop will accommodate control panels from third parties.

"Now you can drop a SWF (Shockwave Flash file) into your Photoshop folder and extend the application," Nack said. "This is going to be a huge shot in the arm for people developing on top of the application."

Adobe plans to release a Configurator application to help people create their own panels, part of the company's effort to make a Photoshop that can be better tailored to specific tasks. That software currently is scheduled to arrive sometime around the end of October, Nack said.

One benefit of the Flash technology is it's network-enabled. That permits integration, for example, with Adobe's Kuler site for creating harmonious color combinations, so palettes can be imported into Photoshop. Another possibility is a "geo" tab that could be added while browsing image information, showing where on a map a geotagged photo was taken.

Other features
The new version has a number of other features, though Nack emphasized work to polish existing abilities, too, such as the ability to select and delete multiple channels. There are some notable changes, though.

• Content-aware scaling, known as seam carving from its research days, lets users change an image's proportions while protecting important areas from distortion. That's a useful option for those adapting content for small screens on mobile devices, for example.

• Panoramic stitching gets new options: it can be used to create full 360-degree wraparounds, so the right and left edges mate correctly, and it corrects for lens vignetting, which could cause dark-and-light undulations in even-toned areas such as the sky.

• With the 3D mode in CS4 Extended, people can paint directly on 3D objects rather than having to unwrap a skin, paint on it, then rewrap it.

• The Camera Raw 5.0 import filter inherits some local-editing abilities in Lightroom 2.0, such as the ability to selectively darken or lighten particular patches of a photo.

• A new tool can combine the sharpest parts of multiple photos of the same frame. It takes a couple minutes to run, but can help provide a sharp photograph of a subject--for example a series of close-up shots taken with a macro lens with a very shallow depth of field.