[MPlayer-dev-eng] Adding threaded functionality to mplayer

[Dermot McGahon]

On Fri, 3 Sep 2004 14:13:35 +0900, Attila Kinali <attila at kinali.ch> wrote:


> Yes, teh copy operation from RAM to the video card is actualy what is
> limiting everyting. Just do a quick calculation:
>
> 320*240 pixels * 3 bytes/pixel * 30 frames per second = 6'912'000 bytes/s
> (CIF RGB)
> 640*480 pixels * 2 byte/pixe * 30 frames per second = 18'432'000 bytes/s
>
> Now, the BW you have is anything between 15MB/s to 100MB/s, ie
> it uses 6% to 120% of your time to just copy data (with the above
> numbers). And at this time, the CPU is mostly blocked as it cannot
> access RAM.
>
> Note: the 100MB/s is an estimation on my side, i dont have numbers
> for todays super fast blah blub systems. Is there someone out there
> who can provide some _real_world_ data on how much BW is available
> from RAM to graphics memory with current state of the art PC hardware ?

http://www.pcguide.com/ref/mbsys/buses/types/agpBus-c.html
http://www.computerworld.com/hardwaretopics/hardware/story/0,10801,83187,00.html
http://www.acme.com/build_a_pc/bandwidth.html


Dermot.
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