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Re: [LUG] A couple of questions

 

Tom Potts wrote:
<snip>

>> As regards TV I don't have Satellite so no HD just Standard Freeview and
>> DVD's.but I intended to have around 3 TV Cards for viewing and possibly
>> recording a couple of channels as well (I find the best programmes always
>> run at the same time and you miss one of them) so again figured the extra
>> horsepower would come in useful.
> I'd be intrigued to see what horsepower is required - though I would imagine 
> most of the work would be done on the tv cards themselves and it would be 
> merely data from the cards to disk that you have to worry about and so the 
> bottleneck would probably be the hard drive. As for displaying the video - 
> you could watch uncompressed video at higher def than HD  20 years ago 
> without special hardware.
> IS it just me or are things gong backwards?

To give you an idea, running HD 720p (1280x720) video with a DTS audio 
track on my Phenom, it uses between 20 and 50% of one CPU core.  1080p 
video (1920x1080) won't play without skipping.

1080p video would run fine if either...

A) mplayer/ffmpeg could decode the video using multiple cores (something 
which when I last checked was being worked on but wasn't ready)

or

B) The video cards could be used to offload some of the decoding (this 
is possible on Windows on some video cards).

Actually capturing digital TV doesn't actually require much CPU 
horsepower, it's just decoding it (although Freeview uses about the same 
CPU horsepower as a DVD).  Where analogue TV capture is concerned, 
capturing and encoding from a standard TV card would use more CPU 
horsepower but if you have something like the Hauppage MCE150/300 card 
it will actually encode the video into MPEG2 on the card itself.

Rob

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