Computing Firepower: The CPU's Role in Video Editing
Published: September 3, 2003
By Jason Dunn
The key to a high-performance video-editing system is balance between the components. The CPU is a cornerstone of this equation. Ideally, the CPU should be waiting for everything else to catch up to it—relatively speaking, it should be one of your fastest components. In today's market of 3+ GHz CPUs, prices on mid-range CPUs are constantly falling, and what was high-end six months ago is now mid-range. This means you can get tremendous processing power for relatively low cost.
Windows Movie Maker 2, an upgrade to the video editing accessory that comes with Windows XP, is a CPU-intensive application. Check Windows Movie Maker 2 Download for system requirements and the free download. For more information about using Movie Maker, see two Expert Zone columns, Moviemaking 101 and Moviemaking 202, and Focus On: Windows Movie Maker. To learn more about working with digital video, read my book, Faster Smarter Digital Video (Microsoft Press, 2002).
In this column, I'll talk about the role of the CPU in video editing and give you pointers on how to balance cost vs. performance when upgrading your CPU. Finally, I'll look at some of the new brands available.
Balancing Cost vs. Performance
When deciding what to upgrade on your computer or what to buy in a new one, always remember to balance the cost vs. performance gain. For example, at the time of this writing, the 3.06 gigahertz Pentium 4 is the fastest processor you can buy from Intel. It also carries a fairly high price tag. Yet the 2.8 GHz processor, at only a 9 percent slower clock speed, is more than 32 percent lower in price. This doesn't take into account the hyperthreading nature of the 3.06 GHz Intel CPU, but the difference in price is clear.
Buying on the cutting edge of technology is always costly, so you need to decide what the best use of your money is. In a home movie making system, that 9 percent gain in CPU power probably isn't worth the 32 percent jump in cost, especially when you can take the money you saved and put it into extra RAM or a faster hard drive. When looking at component prices, always look one level below the top tier and do the cost vs. performance comparison. The fastest AMD Athlon XP 3200+ is quite a bit more expensive than the XP 3000+, but the 3000+ offers performance that's nearly as good. Also note that some processors require specific motherboards and memory components. For instance, if you want the AMD Athlon XP 3200+, you'll need a motherboard that supports that processor and DDR400 memory.
Price drops occur almost weekly—whenever new processors are close to being released, Intel and AMD slash prices on their current processors to make some headroom for their new premier processors. When prices drop like this, it's a great time to pick up a new CPU.
How Many MHz Are Enough?
Movie Maker is one of the few applications that I've seen that recommends a 1.5 GHz processor. The minimum requirement is a 600 MHz processor, but my poor 750 MHz laptop has a little trouble keeping up with the real-time software transitions. On a fast desktop computer, Windows Movie Maker 2 functions quite smoothly. If there ever was a need for over-the-top CPU power, digital video is it.
One of my computers is a 1 GHz AMD Athlon, and it's a capable video-editing machine (albeit a bit aged). But with prices on CPUs so low, there's no excuse for not owning something in the 1.5 GHz or higher range if you want an enjoyable video-editing experience. Unless you're doing your video editing on a secondary computer that no one uses, you'll quickly grow tired of waiting for your CPU to finish encoding the video. This is especially painful to sit through if you're saving your final video project with Windows Movie Maker 2 and you picked a high-quality format to save your video project in. The rendering time will be quite lengthy.
Intel loaned me a 2.53 GHz CPU for a test machine I built for Faster Smarter Digital Video, and the CPU was impressive: the raw power and snappiness Windows operated with was noticeably better than my previous CPU. Rendering times were cut by more than 50 percent from what I was used to, and previewing my video was nearly instantaneous. Intel packs a lot of power into their high-end Pentium 4 CPUs, and this made a huge impact on how enjoyable my video-editing experience was.
Figure 1: The Pentium 4 from Intel.
AMD makes their own high-end CPUs. The Athlon XP 3200+ is currently the flagship of their product line. The competition between AMD and Intel means ever higher performance and lower prices for you, the consumer.
Figure 2: AMD Athlon XP.
How Much Does CPU Speed Matter?
Here's one example: Turning a 178 MB WAV file into an MP3 by using a Pentium 4 1500 MHz (1.5 GHz) CPU would take 243 seconds. That same file encoded using a Pentium 4 at 2200 MHz (2.2 GHz) would take 165 seconds—a speed savings of 47 percent! That might not mean much for a single audio file, but apply that speed gain to a 60-minute project, and you'll save hours. Unfortunately, there's no accurate way to predict how much a faster CPU will improve your video rendering speed—many factors influence this. But it's safe to say that a faster CPU will always help your project.
When using Windows Movie Maker 2, the CPU plays a significant role in how responsive the program is, especially in the following three areas:
| • | Scene Detection: When you import a new video clip, Windows Movie Maker 2 will analyze the video, looking for scene breaks. This helps a great deal with editing because it enables you to drag and drop the video by scene, skipping over the moments when the video camera was aimed at the ceiling. This process is very intensive, however, and requires a great deal of CPU power. The faster your CPU is, the faster this detection process will go. |
| • | Video Previews: After you've created your video, you probably will have used several transitions and video effects. When you preview your video with these effects applied, the software will layer them over your video in real-time. This means that unlike many other video editing applications, you don't have to wait for a preview to render. This is a big time-saver, but it only works well if you have a powerful CPU. On my 750 MHz laptop, the transitions are blocky and the video playback skips. The same procedure on a 2.53 GHz CPU results in smooth effects previews and perfect transitions. The better your video preview goes, the faster you can finish the project. |
| • | Final Rendering: Once you've finished your video project, you'll probably want to save it in at least two formats: one low-quality version appropriate for e-mailing or posting to the Web, and one high-quality version appropriate for burning to DVD or archiving on your computer. As wonderful as Windows Media Video is for compressing large video clips into small files, that intense compression takes a great deal of CPU power. The faster your CPU, the faster this final rendering can occur, and the more you can do with your time. |
Intel CPUs vs. AMD CPUs
In the battle for CPU dominance, Intel and AMD trade places as front-runner several times each year. So what does all this mean to you, the end user? Either processor will perform beautifully in all scenarios, and there are no longer any issues of one processor being more Microsoft Windows-compatible than the other, so your decision should be based on price and compatibility with your current hardware. If you have an Intel CPU in your current machine, you may be able to upgrade to a faster CPU with little hassle. The key factor is your motherboard—you'll need to find out what type of CPU speeds it supports. If you're currently using a Pentium 4 CPU, your motherboard will likely support any current Pentium 4 CPU. If you have an older motherboard, such as one using a Pentium III CPU, you'll probably need to upgrade your motherboard. And when it's upgrade time, you can pick any motherboard and CPU combination you want. Remember the cost vs. performance ratio explained earlier, and you can't go wrong!
Cutting-Edge CPU Technologies
In addition to the CPU technologies mentioned so far, a few new steps have recently been taken in the never-ending march of improvements to how fast computers can crunch data. The first major change is for mobile warriors who are interested in using a notebook for video editing: Intel has released a new set of mobile-friendly technologies dubbed Centrino. Centrino-based notebooks have built-in 802.11b WiFi wireless technology, and the new Pentium 4 M has a massive 1 MB of cache. This is double that of a standard Pentium 4 CPU, resulting in blazing performance—which means it's great for video editing. And since laptops are always restricted by their battery life, and a dead battery means no video editing, Centrino-based laptops last a great deal longer than a normal laptop—up to six hours on a single charge (this varies depending on the model). Centrino laptops are generally high-end, which means they come with large hard drives (40 GB to 60 GB), USB 2.0 and FireWire ports, fast video chips, and some even have DVD burners built in! If the thought of working on a video with Windows Movie Maker 2 anywhere you want sounds appealing, check out the Centrino notebooks made by Acer, Toshiba, HP, Fujitsu, and others.
Figure 3: Intel's Centrino technology means great things for video-editing mobile warriors.
Figure 4: AMD's Opteron 64-bit CPU.
One of the biggest revolutions in the CPU world was the recent emergence of the 64-bit CPU. Most current CPUs are 32-bit. The move to 64-bit processors and 64-bit software will have a profound impact on the video-editing world in due time. Intel was the first to release a 64-bit processor, but AMD was the first company out of the gate with a 64-bit CPU that's compatible with current 32-bit software. The Opteron, although new and just starting to be tested by the public, offers both solid 32-bit and 64-bit performance. The biggest performance gains will be on hold until the software we're using is fully 64-bit, however. Once that happens and we're running 64-bit versions of Microsoft Windows and using 64-bit video-editing software, we'll see significant performance gains. This isn't something that will happen quickly, though—it will likely take at least a year for all the pieces to be in place, and even that's a little optimistic.
Your Next CPU
I hope this article has proved helpful to you. The most important thing to remember about buying a new CPU is that when it comes to video editing, faster is always better, but not if it breaks the bank! A wise course of action is to buy one step below the fastest CPU speed and invest the money you've saved in more RAM or a faster hard drive. 64-bit CPUs are certainly the wave of the future, but it will take a couple of years for that high-end technology to trickle down to mere mortals like you and me. Until that happens, enjoy pushing your current CPU as hard as you can with digital video and Windows Movie Maker 2!
Jason Dunn is an avid digital media enthusiast who also writes about mobile technology. He's the author of several books, including PhotoImpact 7 Power, Short Order Microsoft PhotoDraw 2000, and Faster Smarter Digital Video. Jason also runs Kensai, which focuses on helping companies successfully navigate the online world.
