pc vs mac 速度測試 , 結果..pc 比 mac 快
Apple has been advertising its G4 processors as faster than Intel Pentium 4 chips -- and that megahertz don't matter -- often citing higher performance on certain Photoshop filters. But we were wondering how the fastest Mac stacks up against an equivalently equipped PC in real world situations regularly encountered by digital video compositors. So, with Adobe After Effects 5.5 installed on the mightiest Mac available at this writing, a Power Mac G4 with dual 1GHz processors, and the PC version of After Effects 5.5 installed on a dual Athlon 1800+MP by Polywell, we did a series of six After Effects 5.5 projects that tested a variety of aspects of the rendering speed of each platform. Here are our test results. 
First, let's take a look at the two machines we used for testing. We took every opportunity to make the machines as evenly matched as possible. The dual AMD Athlon MP machine, running Windows XP Professional, is a Polywell 890E (click here for a detailed review), which originally had 1GB of RAM, but we removed two of the four 256 MB RAM sticks to equip it with the same amount of RAM as the Mac G4, 512MB. An Athlon 1800+ chip runs at 1.533 GHz, which AMD says is roughly equivalent to a 1.8GHz Pentium 4 chip. This is significant, since currently the fastest Intel chip is now at 2.4GHz, so this isn't the fastest PC available at this date. Against the Athlon MP entry, we have a dual G4 Power Mac running OS X 10.1.3, with two 1GHz Motorola G4 processors. At first glance, this would seem to be a mismatch, but since the G4 chips have an Altivec processor and can do more operations per clock cycle than the Athlon MP, we expected the G4 to be able to easily keep up with its Athlon counterpart in After Effects rendering. 
How We Tested 
For our benchmarks, we used six projects featured in the excellent new book, After Effects 5.5 Magic, a tutorial tome by New Riders Publishing. Included in the book is a CD with all the QuickTime, Photoshop and Illustrator files for the projects for both Macs and PCs, along with the After Effects 5.5 project files for each platform. We transferred all the project and media files from the CD onto each workstation, and began our testing. Render settings for all the tests in this article were identical on both platforms, set at Best and rendered lossless at 720x486. Each file was output to its platform's native format with no compression added -- on the Windows platform, they were uncompressed Video for Windows files (.avi) and on the Mac OS X platform, they were rendered to the QuickTime animation codec (.mov). We also tried rendering both the Mac and the PC files to the same QuickTime animation codec, but that made no difference in our results. So we decided to stick with each OS's native video format because that would be the most likely method to be used in the real world. Also, even though we discovered it made no difference whatsoever, we used a single IBM 75GB ATA-100 disk on the Polywell PC instead of its original RAID array for the testing. 
After the testing was done, the files for each comp were compressed for QuickTime streaming using our custom settings for Sorenson 3 via Discreet Cleaner. Since the streaming QuickTime movies for Mac and PC were identical, we've included just one movie for each test. The times on each graph are represented in minutes and seconds. The Polywell machine, as configured, currently sells for $2564, while the similarly configured Mac G4 sells for $2870. 
Simple Animation 
The first test involves a simple cel-style animation. It consists of a pict file created in Photoshop that was used as a background for tracing paths, which were then animated and filled with another pict file making the pink color of the face. It's a goofy, simple animation, but it shows how well the processors can calculate the paths and render the final composite. In this test, the Athlon machine handily beat the Mac, taking 9 seconds to render the project, while the Mac took 16 seconds.
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Video Composite 
Here's a project that's commonplace for After Effects users. It's a composite that uses a number of effects in one shot. This comp uses a green screen layer, a CGI layer and then an element that was shot on film. The background layer is the castle hall behind the actors. The two men were shot against a green screen, and a QuickTime movie of moving smoke was also layered into the shot. All three layers are combined to result in a realistic final composite. This rendered into a 55MB QuickTime movie on the Mac and a 57 MB .avi on the PC even though the shot was only two seconds long. As you can see, in this test the Mac came close to matching the PC, taking only 12 seconds longer to render the composite
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Data Project 
This test concentrates on animating layers from Photoshop and Illustrator. It animates randomly sequenced 1s and 0s traveling across the screen at different rates. Green lights were also added, making this the kind of graphic that might be used as a background for statistics in a production. The text elements were imported into After Effects as a three-layered Illustrator file. Since these are vector graphics, they could be scaled to any resolution within After Effects without diminishing their resolution. After the text layers were skewed using 3D effects, lighting effects were added to give the numbers a green cast. This kind of project is indicative of many text animation sequences that are commonly created in compositing software. 
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Gambler 
In the book After Effects 5.5 Magic, this project was originally intended to be exported to the SWF (Shockwave Flash) format, but we processed it in 720x486 (QuickTime and AVI) pixels to see how our contestants could render this composite of Illustrator files in a more broadcast-bound situation. It's a good example of a 2D graphic composite that originated in Illustrator, which is many compositors' bread-and-butter. The Mac lost this one by nearly 33%.
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