ATi DXVA :: MPEG-2 VLD/Bitstream

[CiNcH]

Hey guys,

it is a fact that UVD2 supports VLD/Bitstream level decoding for MPEG-2. However, the driver does not provide a DXVA profile for it, but only for iDCT profile.

There is a hidden tweak however to enable this profile via DXVAChecker's 'Video Acceleration Settings...'. The key is called 'VForceUVDMPEG2VLD'. The 'CyberLink Video Decoder' operates in BSP profile afterwards. People are reporting a green picture however. So ATi simply seems to have disabled the feature because the driver is not yet ready.

I only have a HD 3650 with UVD+ currently, so I can't test whether newer drivers solve this issue. Maybe some people want to comment on their experience with UVD2 hardware...

[tetsuo55]

None of the registry settings i tried reveal mpeg2 as a VLD codec on my hd 4770.

[CiNcH]

I can't test it myself but only refer to this thread (http://forums.amd.com/game/messageview.cfm?catid=279&threadid=127844&highlight_key=y&keyword1=MPEG-2%20Bitstream).

[STaRGaZeR]

No change since the last time you asked for it...

http://thumbnails23.imagebam.com/7702/82bdca77013471.gif (http://www.imagebam.com/image/82bdca77013471)

[Blue_MiSfit]

I'm curious - why does this matter? MPEG-2 is so light on the CPU versus H.264, I can't see it really making a difference? Even on older systems.

~MiSfit

[tetsuo55]

I'm curious - why does this matter? MPEG-2 is so light on the CPU versus H.264, I can't see it really making a difference? Even on older systems.

~MiSfitThe UVD core uses less power/watts to decode the stream than the cpu would. This is about quietness and powersaving.

That said 1080p/i cannot be decoded with mt athlonxp 2600.

[CiNcH]

When reading the Avivo HD White Paper, you will also find out that ATi is advertising VLD level MPEG-2 decoding with UVD2, so...

[roozhou]

The UVD core uses less power/watts to decode the stream than the cpu would. This is about quietness and powersaving.

That said 1080p/i cannot be decoded with mt athlonxp 2600.
Even a 1.8G P4 can decode 1080i/p 30+Mbps MPEG2 without problem.

[CiNcH]

First off, congratulations to your P4. The least efficient CPU ever ;) . At least it is no Prescott. Green thumbs down.

Decoding it via a dedicated ASIC is way more efficient from a power consumption point of view..

The DXVA iDCT profile is just as inefficient as doing it all the way via the CPU, as no dedicated ASIC is used in this case, but some operations are offloaded to the GPU's shaders, which are just as general purpose natured as the CPU.

Why not use the dedicated ASIC if it is there? And ATi certainly has to do something. Advertising but not delivering. Is this the way one is supposed to do business nowadays? Just disabling the feature and concentration on a 1% performance gain in some game? Nice..

[CruNcher]

I wouldn't be surprised if it's get active with a new product line but only for the new Product (even if technical possible on the old one) ;) that's the same way Nvidia also does certain things with Software restrictions to have feature sets for new Products and a additional selling points.

[Midzuki]

First off, congratulations to your P4. The least efficient CPU ever ;) .

It seems your I.T. dictionary doesn't have an entry for
"80286", for example. :)

[CiNcH]

It seems your I.T. dictionary doesn't have an entry for
"80286", for example.
Problem is that I am not old enough ;) . Just wanted to exaggerate a bit. Let's say one of the least efficient CPU's ever..

[Midzuki]

CiNcH meant: :devil:

Problem is that I am not old enough

Let's say one of the least efficient CPU's ever..

That's better... :) There was no History before the 80-column punch cards. :p