GPU Accelerated H.264 Decode

Transcode acceleration isn't the only thing that the R5xx GPUs will be doing; as we saw at Computex, ATI has had working H.264 decode acceleration for months now, and it will be a requirement for all Avivo platforms.

All Avivo graphics cards (e.g. R520, RV530, RV515) will feature decode assist for H.264, MPEG-2, MPEG-4, VC-1 and WMV9. This feature will be enabled on the day that the products ship, through Catalyst.

Keep in mind that we're still talking about GPU assisted decode, so there are still a lot of functions that are done by the CPU. Avivo GPUs will perform in-loop deblocking, motion compensation and inverse transform.

ATI performed the same demo for us that we saw back at Computex (this time on a dual core machine however), and the performance results were very similar. CPU utilization dropped from 90% down to around 30% while playing a 20Mbps H.264 stream.

Based on ATI's chart, it's not too hard to see why the GPU assisted H.264 decode reduces CPU utilization by so much. Note that reverse entropy does appear to eat up quite a bit of CPU time, which the R5xx GPUs do not handle. This is most likely why CPU utilization is still not insignificant even with decode assist enabled.

The H.264 decode acceleration of Avivo GPUs is quite important, mostly because both the next-generation DVD standards (HD-DVD and Blu-ray) will both use H.264 as the encoding format for video stored on the discs.

For what it's worth, NVIDIA has committed to delivering H.264 decode acceleration later this year on their GeForce 7 based products; but we have yet to see a live demo of the technology.

GPU Accelerated H.264 Transcode Improved De-Interlacing and Video Scaling
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  • ViRGE - Tuesday, September 20, 2005 - link

    Hexus has confirmed Avivo platforms will be HDCP/HDMI compliant.
  • ViRGE - Tuesday, September 20, 2005 - link

    Didn't ATI already promiss this feature last time? When they launched the X800, they advertised accelerated encoding/decoding of MPEG1, 2, and 4; and right now all they've actually done is decode acceleration of 1 and 2, with no sort of encode acceleration to be seen. I'm really getting leery of all these video features that fail to materialize.
  • MrJim - Tuesday, September 20, 2005 - link

    With my Radeon 9800 i can accelerate divx when i use the divx player, thats mpeg4 for me. But im looking forward to better support in the hardware.
  • ViRGE - Tuesday, September 20, 2005 - link

    That's not decode acceleration, that's simply a form of deblocking where the Divx codec doesn't deblock the video then passes it to the 9800 to deblock(and I use the term loosely because the Divx codec itself does a better job, IMHO).
  • mongoosesRawesome - Tuesday, September 20, 2005 - link

    nvidia has really aggrivated me with their purevideo. they tout purevideo as a feature of their graphics cards, but in order to enable it, you have to pay them 20 dollars for their purevideo software. after paying 400 dollars for a graphics card, i expect the features listed for the graphics card to be included in drivers. i think anandtech and other hardware review sites need to be more explicit about how purevideo is only enabled after purchasing extra software from NVIDIA.

    while I haven't been as impressed with ATI's video game performance as of late, WMV9 acceleration is included in their drivers all the way back to my 9800 Pro, a feature NVIDIA wasn't able to deliver with their AGP 6800 series cards, and only available after paying them for extra software on newer cards.
  • Rock Hydra - Tuesday, September 20, 2005 - link

    I agree. That pissed me off when I found out about having to buy additional software. Maybe a 3rd party has come up with a way to enable the abilities of purevideo. Even better, for free. /crosses fingers
  • Jep4444 - Tuesday, September 20, 2005 - link

    ATI drivers work fine for games, ive never had one game fail to run on me through two Radeon cards(ill admit the drives for the Rage sucked as i couldnt get quite a few games to run on that thing)

    I'm curious what Intels reaction to this since it treads into the same territory as Viiv, i think ATI should try to strategically place themselves together if they want Avivo to suceed to its full potential
  • Myph - Tuesday, September 20, 2005 - link

    Only thing really holding me back from going ATI, I just can't trust that their drivers are going to work for ALL games, all the time.
  • photai - Tuesday, September 20, 2005 - link

    maybe you should consider how it performs as well. I think it is important too.
  • Griswold - Tuesday, September 20, 2005 - link

    Humbug. Their drives have no more problems with brand new games than nvidias.

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