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mjcrxx
01-19-04, 07:11 AM
Hi,

Does anyone know if nvidia personal cinemas, in particular the Geforce FX5200 variety have onboard hardware MPEG-2 encoding and/or decoding or if it just uses software. Any help appreciated.

mjcrxx
01-19-04, 07:48 AM
Ok, looks like I'll be able to answer my own question. For anyone else who is interested, here goes:

I've done some more research and according to Snapstream they don't have hardware encoders. Also the fact that nvidia doesn't explicitly mention how they encode/decode gives a good indication that it is via software. I think their might be some hardware support, but the bulk of the encoding is done by software. Ditto All in Wonders by the way.

aapo
01-19-04, 09:46 AM
Originally posted by mjcrxx
I think their might be some hardware support, but the bulk of the encoding is done by software.

It's always that way, except in the specialized de/encoder cards. After all, it's impossible to predict all the future codecs, which would be needed for full hardware implementations. That's the stronghold of a CPU: it can be programmed to de/encode all possible algorithms. :)

Some of the work is done by the card hardware, though. There are certain algorithms that are used so widely that they can be hardwired to the chip. For example colorspace conversions between various YUV, RGBA, YUY2 etc modes can usually be done with hardware. And those nasty YUY2 modes are the basis of the most video codecs (including all mpeg variants), because human eye sees luminance channel better than the chrominance channels. Furthermore, video scaling is done with hardware, because software scaling would be very slow and it's easy to do with hardware. One could even exploit the chip's 3D functions to scale the video frames - you'd get a nice and fast trilinear filtering for the video even with a slow 3d card.

Anyway, after these hardware accelerations your CPU has only a moderate load to process. :p