ATI Avivo Video Pipeline (Cont.)
Windows Media Video 9 Acceleration: Microsoft's Windows Media Video 9 (WMV9) HD format was accepted by the SMPTE HD-DVD consortium as a new HD format. The Windows Movie Maker software, which comes bundled with Windows XP, makes it easy for consumers to edit and save their favorite videos. These videos are saved in the .WMV format. Most of today's high-end GPUs include dedicated hardware to accelerate the playback of WMV and WMV-HD content for fluid full frame rate video even on systems with entry-to mid level CPUs. Previous generations of GPUs were not able to support WMV9 decode acceleration, so often times HD WMV9 content would drop frames when being played back on legacy hardware.
To characterize CPU utilization when playing back WMV HD content, we used the performance monitor built into Windows XP. Using the data provided by performance monitor, we created a log file that sampled the percent of CPU utilization every second, while playing back the 1080p version of the "Magic of Flight" video available on Microsoft's WMVHD site. The data was then imported into Excel to create the graph below. The graph shows the CPU utilization for a GeForce 7800 GTX, a Radeon X850 XT PE, and a Radeon X1800 XT using Windows Media Player 10, patched using the DXVA update posted on Microsoft's web site (Update Available Here).
Average CPU Utilization (Athlon 64 FX-55 @ 2.6GHz)
|GeForce 7800 GTX||Radeon X850 XT PE||Radeon X1800 XT|
Before we talk about the numbers posted above, we have to report on a problem we experienced with ATI's X1000 cards playing HD content with Microsoft's DXVA patch applied to Widows Media Player 10. With the first set of drivers supplied to us by ATI, X1000 cards would playback WMV HD videos with garbled blocks over a majority of the video. We reported the problem to ATI and were sent a second set of drivers that helped with DVD playback image quality, but didn't resolve the WMV HD playback issue. Instead, with the second set of drivers caused WMP 10 to display a black window when running a WMV HD video. So, at this point in time consider hardware accelerated WMV HD playback "broken" on the X1000 family. ATI claims they'll have this issue resolved in a future driver release.
With that said, we recorded CPU utilization numbers using the first set of drivers that we received. The movie didn't look right, but the audio was there, and we could see some of the video. These numbers could very well change considerably with a future driver release, however. As it stands now, the Radeon X1800 XT fared only marginally better than the older Radeon X850 XT but X1800 XT utilized slightly more CPU cycles than a GeForce 7800 GTX.
Next up, we have a new addition to the HotHardware testing arsenal, the HQV DVD video benchmark from Silicon Optics. HQV is comprised of a sampling of video clips and test patterns that have been specifically designed to evaluate a variety of interlaced video signal processing tasks, including decoding, de-interlacing, motion correction, noise reduction, film cadence detection, and detail enhancement. As each clip is played, the viewer is required to "score" the image based on a predetermined set of criteria. The numbers listed below are the sum of the scores for each section. We played the HQV DVD using the latest version of NVIDIA's PureVideo Decoder on the GeForce 7800 GTX, and as recommended by ATI, we played the DVD on the ATI hardware using Intervideo's WinDVD 7 Platinum, with hardware acceleration enabled.
Somewhat surprisingly, the GeForce 7800 GTX did a better job playing the HQV DVD benchmark than either of ATI's cards. The GeForce 7800 GTX excelled in the film detail and "jaggies" tests, where ATI seemed to falter a bit. Overall, ATI's hardware did well, but NVIDIA had a marked advantage in a majority of HQV's tests. We were also surprised to see the X1800 XT score so closely to the X850. This fact leads us to believe the advanced features of the new Avivo video pipeline are not being fully exploited with ATI's current drivers. Hopefully, this situation will change for the better with future driver releases.