Does a media center extender use the computers video card

Question

I am wondering if the video graphics quality of the streaming computer affects the quality or playback of the extender such as an Xbox360 i.e. would my extender experience be better with a high quality video card versus the integrated Intel graphics (which does have smooth HD playback in both MKV's and in media center HDTV channels) which the computer is currently using.

Answer 1

This issue is slightly interesting. Media Center Extender functionality works over RDP: When you navigate your media library through the WMC interface on the xbox, you're actually working through an RDP session that the xbox has opened to your computer, which is running WMC. When you start media playing, the computer sends the media to the xbox over a different channel, using a standard media streaming protocol.

So, the interface is rendered on your computer but the media itself (i.e. the video) is not. Depending on your OS, media extender, and the formatting of the video, it might be transcoded for streaming. Let's look at these two issues:

1. Since WMC is actually running on the host machine, does this mean that you could improve the interface quality by upgrading your computer's graphics card? No. RDP works by sending high-level draw commands over the network, so all of the actual rendering is still done by the client machine. Your video card is not used for this process.
2. What about a video I'm watching? since it's possibly being transcoded on the host machine, can media quality be improved by upgrading the host machine? The answer to this is also no, with limited exceptions. Most media transcoding is still performed on the CPU (few decoders/encoders are GPU enabled), and I doubt Microsoft is using a cutting-edge GPU enabled toolset, so chances are your graphics card isn't used at all by the transcoding process. What about upgrading your CPU? A modern CPU should be able to keep up with the transcoding handily. If you have a poor enough performing computer than transcoding can't occur at 100% at the quality determined by other factors, I suspect that WMC would fail to stream anything at all.

WMC adjusts quality automatically to suit your network, so the factor limiting the quality of streamed media is going to be the quality of the home network. Is the extender connected by WiFi? cable it if at all possible, WiFi adds a scourge of potential problems to a media streaming setup.

Answer 2

Hmmm, I took a brief look and it seems like it can go both ways.

As such, the device can render the interface even though the Media Center-specific software (or the plug-ins) might not be installed there. However, the media files are streamed over a different protocol. To render the media, the Extender needs to have an implementation of the codec used to package the media locally installed on the Extender; having the codec on the host computer is not enough. Alternatively media can be trans-coded on the fly by the host computer to a codec that is supported by the Extender. In Windows 7 this is now a standard feature which will probably relieve Extender vendors in the future from having to include such a wide variety of codecs.

(From Wikipedia Article, Windows Media Center Extender)

That would suggest that the extender uses native decoding when possible, but otherwise, the host must transcode the media. The interface, however, is rendered entirely by the host.