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Join Date: Apr 2000
Location: Fairfax, VA, USA
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Two of the current HD cards can downconvert to 480i or maybe 480p (I'm not quite sure which format), but you would have to capture this data using a low compression codec on all but the fastest machines. Currently, the software for these cards does not support the capture of the downconverted HDTV signal, but is should be possible.
In any event, real time storage and encoding of standard def TV pushes most current PCs right to their performance limits. PCI bus traffic being one of the primary areas that causes dropped frames if you have a fast enough CPU to compress in real time.
Just to explain the technology involved a little more if your interested, the software used by the HD card uses directshow filters there are ways to insert a filter into the render pipeline that will attempt this, but since the application software builds the filter graph internally, it would take a little bit of hacking to get it to work.
Ah, Tom beat me to the punch, and that is a nice and easy way to convert the files. I think Tom is using the Elecard decoder and maybe a MPEG-4 encoder such as Divx. But as Tom says, you first have to record the HDTV stream and then convert it to something else. That takes quite a lot of CPU time so this in not a real time solution.
[This message has been edited by JoeFloyd (edited 07-02-2001).]