Page 4 of 4: Analysing the results

Your Fraps benchmark result should look like this:
2006-06-03 18:59:24 - mplayerc
Frames: 2689 - Time: 112153ms - Avg: 23.976 - Min: 22 - Max: 26

The important figure is the on in bold above. This is your average framerate.

The framerate of the Pirates of the Caribbean trailer used is 23.976 frames per second. The result above shows that while the system was able to play back the file, it still results in some frames being dropped and some skipping in the file. In other words, the closer the above number is to 23.976, the more likely your system will be able to handle high definition DVD playback.

Below are some sample results returned from our test systems, along with the test system's specs.

Test System 1:
AMD XP 2500+
NVIDIA GeForce FX 5700
Resolution: 1280x1024
720p Result: 23.976 (full framerate)
1080p Result: 11.916

Test System 2:
Pentium-4 3.2 GHz
ATI Radeon 9800 Pro
Resolution: 1280x1024
720p Result: 23.976 (full framerate)
1080p Result: 17.136

Test System 3 (Notebook):
Pentium-M 2 GHz
NVIDIA GeForce Go 6600
Resolution: 1280x800
720p Result: 23.976 (full framerate)
1080p Result: 16.766

Test System 4 (New PC):
Intel Core 2 Duo E8500
4GB DDR3 1333 MHz RAM
ATI Radeon HD 4850 512MB
Resolution: 1920x1080
720p Result: 23.976 (full framerate, average CPU utilization: 15%)
1080p Result: 23.976 (full framerate, average CPU utilization: 30%)

The sample results above show that playback was perfect for the 720p clip on all the test systems. The 1080p was a totally different story, with only my new C2D system being capable of 1080p playback at full framerate - all the other systems were unable to play the clip at the full framerate. For the new C2D system, I've also included the CPU utilization, which is 30% without video acceleration for the 1080p clip.

Please note that the ffdshow H.264 decoder used (libavcodec) is not the most efficient one around. The most efficient decoder at the time of writing appears to be the CoreAVC codec. The professional version of this codec will also eventually features GPU acceleration support, which is simply a way of using your (most likely very powerful) graphics card to help with the video decoding. CoreAVC is not freeware, but it's well worth checking out.

GPU acceleration is already available in NVIDIA's PureVideo decoder (obviously for NVIDIA GeForce series 6 and 7 cards only), which is NVIDIA's GPU acceleration driver. ATI's version of PureVideo is called Avivo, which is actually free and available for the X1000 series as part of the Catalyst driver set (5.13 or later). You will require a separate Avivo compatible decoder, like the one PowerDVD uses (although it does not seem to be as compatible as ffdshow/CoreAVC). For the testing of this article, PowerDVD (and now WinDVD 9) forces acceleration when Blu-ray is being played, which makes it impossible to test CPU usage without acceleration turned on.

All of these decoders are still constantly being improved, and performance has risen along with each new version. Using an older Alpha version of the CoreAVC codec (considered by many to be the most efficient out there), I was able to play back the 1080p clip at full frames on "Test System 2", so it shows the importance of decoder efficiency.

Now actual Blu-ray playback may require more CPU cycles, as there is also more advanced video decoding, higher bitrates being used, as well as decoding of the encryption system - so if you can get CPU usage to around 30%, then you should be able to play back Blu-ray perfectly without GPU accleration, with some room to spare. Of course, finding a GPU (even integrated ones) without HD acceleration these days is harder than finding one with HD accleration. On "Test System 4", Blu-ray playback with GPU assisted decoding (Avivo HD, full acceleration of H.264) will only require around 10 to 15% CPU usage, for example. If you can't even play back the 720p clip at full frames, then I think a system upgrade might be a good idea.



  1   2   3   4