On 6/8/06, klaas de Baas kdebaas@hotmail.com wrote:
CPU utilization is still high. My questions:
- was I wrong in supposing that the GPU would take over processing tasks
of the CPU?
Only the 3D OpenGL parts of GEM (Geos, Manips, Particles) are accelerated by the GPU. You can do image processing using the GPU and objects like fragment_program though. Any pix_ object is handled by the CPU.
- what would be a realistic cpu load for 24 hours a day, 2 months?
As long as the CPU and other components are properly cooled and stay within the rated specs any CPU load should be tolerated. CPUs are usually tested using a 'thermal virus' code that is at an extremely high level of efficiency, which GEM (or any real world program) will never reach.
- Does anyone on the list have experience with running fullscreen
gem-patches with specs such as pentium III, 800Mhz, 384 Mb, and do they have any pointers on how to optimize (such as using a different size video, codec, etc..?)
That is fairly old hardware so don't expect a lot out of it. It should do 320x240 video with some processing though. I would recommend a PCI cpature card with efficient DirectShow drivers that do things like scaling, color space conversion (overlay), deinterlacing and other functions in hardware on the card. I suspect the device you are using relies on inefficient software to do those things, hence the high CPU load.
Also, use a spigot object to gate the path going to the motion detection objects. You usually don't need 30fps for motion detection and int your case you could probably play several frames per detection with similar effect to full rate.
I am also working on another computer (faster pIV, 512MB etc, etc...). I
noticed that playing a video in mediaplayer requires less than half the cpu load of playing it in pix-movie or pix-film.
- Can anyone explain why this is?
GEM uses old VideoForWindows code to play AVI files which is slower than DirectShow. Mediaplayer uses a full DirectShow path and there are a number of efficient paths when you can do that. GEM has a full OpenGL rendering engine so we cannot use things like the DirectShow hardware mixer and scaler, and once you get off the narrow predetermined DS path things slow down qite a bit. There are plans to use Directshow for loading AVI files in the future, but it will still not be as efficient as MediaPlayer (hopefully it will be close though).
cgc