MKV h.264 Hardware Acceleration DXVA

kiffies · **22nd March 2008, 04:48 PM**

When I play back MKV's my CPU usage is very high (around 90% on a Pentium 4 3.0Ghz HT, with 2 gig of RAM) This is bearable normally, but in heavy action scenes the audio goes out of synch and if recording starts in the background it all goes to hell.

I Believe my GFX card (Radeon 2600XT) has hardware decoding support for H.264 but I can't seem to offload the decoding to it.

I was using ffdshow, until I found out it doesn't support hardware acceleration (Is that correct?)

So I've installed Powerdvd7 and checked the "Enable hardware Acceleration" option. I've used the graphedit tool to make sure the Powerdvd codec is being used, but the CPU usage is still high, infact it seems worse!

Any ideas anyone?

kiffies · **1st April 2008, 04:33 PM**

Anyone...?

Severus606 · **1st April 2008, 06:34 PM**

Edit: The latest information I can source indicates that PowerDVD can handle x264 decode offload from an MKV container, but Haali currently has issues handing off the x264 stream to the Cyberlink codec. You may be able to open the MKV's directly in PowerDVD for decode offload, but there doesnt' look to be a current solution for MCE.

kiffies · **1st April 2008, 07:04 PM**

Finally, thanks for the reply.

The info you posted sounds consistent with the results I'm getting, and from memory you can't open an MKV in power DVD unles someone can tell me otherwise.

Does that mean everyone is just relying on pure dual core power for their MKV's?

Severus606 · **1st April 2008, 07:44 PM**

Yeah the problem is that PowerDVD can happily decode x264, but it doesn't natively support the MKV container. It will open x264 in an AVI container though. x264 in an MKV container would work if Haali properly supported handoff to PowerDVD, but it doesn't, so until Haali gets an update or PowerDVD gets a native MKV splitter, you're screwed

Severus606 · **1st April 2008, 07:48 PM**

Just a note to add that yes, for now you're limited to software decode. To put things in perspective, an E4500 2.2GHz C2D will comfortably decode 1080p x264 up to around 35Mbps (possibly higher, I just don't have any higher bitrate material). It just goes to show the significant IPC improvements of C2D over Netburst, as current x264 codecs are mostly single-threaded (MS have a nice threaded x264 commercial encoder available but I'm not aware of any well-threaded decoders).

The bottom line is you really need a CPU upgrade

But for now give CoreAVC a shot, it sacrifices a little accuracy for much lower CPU overhead.

vlad · **1st April 2008, 07:58 PM**

I have 2-7% of CPU consumed when playing mkv's

Severus606 · **1st April 2008, 08:53 PM**

Quote:

Originally Posted by vlad

I have 2-7% of CPU consumed when playing mkv's

What CPU, what video card, what bitrate MKVs, which splitter and what codec? More info required

vlad · **1st April 2008, 09:00 PM**

Quote:

Originally Posted by Severus606

What CPU, what video card, what bitrate MKVs, which splitter and what codec? More info required

Look at my profile
http://www.xpmediacentre.com.au/community/members/vlad/
Here we do care to put your config into your profile

Severus606 · **1st April 2008, 09:05 PM**

OK, I looked, but there's no info on which x264 codec you use, which splitter, the bitrate of the MKVs, etc. Would be good to know if there is a workable solution available now. Just asking as I have Futurama encoded in 320x240 MKVs and could probably get 2% CPU decoding them on a PIII, but 1080p 40Mbps MKVs are another story