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View Full Version : Does hardware decoding work with GeForce 5200?



zaarain
2004-12-29, 07:56 PM
I just installed gbpvr and noticed that the dropdown for hardware decoding only lists two cards (X-card and something else, sorry I'm not near that machine atm). I have a GeForce 5200 which is supposed to do hardware decoding as well - will gbpvr support it?

On a related note gbpvr, wintv2000, and windows media player all appear to be doing software decoding - I get 100% cpu utilization while playing a .mpg file. Granted I'm trying this on a 350Mhz machine but I expected lots better. Is there something I need to do to turn on support for hardware decoding on the 5200 besides installing the drivers that came in the box?

jmain
2004-12-30, 01:03 AM
These 2 Cards are true Hardware Mpeg2, Mpeg4 Decoder Cards that have Video out. The check box enables the OSD and Video Files to Play through these cards.

To take advantage of the hardware mpeg acceleration of your FX5200 card you need to be running a software decoder that supports the Acceleration hardware of the video card.

The NVdvd Codec and WinDVD 6 etc will have support for this.

I hope this makes sense.

sub
2004-12-30, 01:12 AM
jmain is correct.

The decoding functionality in your card is accessed in a very different way than those specialist hardware decoders supported by GB-PVR (XCard and PVR350). For you to use the decoding features in your 5200, you need to fund a software decoder that is able to take advantage of acceleration features of you card.

zaarain
2004-12-30, 10:10 PM
Ok, so what you're basically saying is that the field in gbvar that says hardware decoding isn't really about hardware decoding, it's about selecting specialized gbpvr-specific drivers. Similiarly software decoding isn't really about software decoding, it's just selecting generic drivers that may or may not do hardware decoding.

I installed the nvdvd codec and I now get acceptable playback - roughly 30% cpu with both procs turned on. Still higher than I would like but acceptable. If I boot with only one proc than playback is about 60% so DirectShow is doing a good job of load-balancing. Recording is only about 3% on the two-proc configuration which is excellent. I wonder why playback doesn't get similiar figures?

Actually I only get the low cpu figures if I minimize gbpvr (by default it's rendering to both the monitor and the tv) which tells me that the hardware decoding is only working for some special config. Since gbpvr is minimized and doesn't have focus I don't have access to the controls for fastforwarding, etc. If I leave gbpvr un-minimized then I'm at 85% cpu and get stuttering and mpeg motion artifacts.

Is there a way to get gbpvr to not render to the monitor but still have the tv going?

sub
2004-12-30, 11:07 PM
Quote[/b] ]Ok, so what you're basically saying is that the field in gbvar that says hardware decoding isn't really about hardware decoding, it's about selecting specialized gbpvr-specific drivers. *Similiarly software decoding isn't really about software decoding, it's just selecting generic drivers that may or may not do hardware decoding.
The hardware decoding setting is for selecting hardware decoders. When you use one of these babies, you'll get about 3% CPU usage and an excellent picture. The GeForce 5200 is not in the same league.

When you select to use software decoding, then GB-PVR passes all decoding requests to a software decoder. NVidia have some hack in their software decoder that can take advantage of special features of their cards which reduce the load on your CPU, but dont be confused - this is nothing like a real hardware decoder.

This ability to output video to the monitor and TV is a feature of your nvidia drivers, and I have no control over it. GB-PVR only thinks its displaying to the GB-PVR window, it doesnt know your nvidia is intercepting the video and also sending it to the tv out. If I try to stop it going to the monitor, then it'll also not go to the tv out.