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subbiah
01-14-2004, 01:54 AM
Hi,

I want to display Live video image (2D data)coming to me at 640x480 resolution and 3fps speed my Intel Desktop motherboard based hardware with XFree86 4.3.0 & RedHat Linux 7.2. The data is coming to me in the form of RGB and 24bit color depth.

I have to zoom the data by factor 2 and display on my portion of the screen. Does any hardware accelleration can be used for the zooming operation.

The time latency for the display of image should be less than 30ms is expected.

Can I use the DRI Support with Open GL for getting the good performance?.

Can any one suggest me the good way of approach for this development?.

Thanks.

dorbie
01-21-2004, 12:26 PM
Get the image in memory (that's your problem)and either use glDrawPixels or glTexSubImage2D to a texture and draw on a quad.

The second method would be the best and would allow you to use hardware filtering during the zoom if you chose to.

If you use OpenGL for this and link correctly and have your xserver & drivers installed & configured correctly then you will get fast performance via the DRI automatically (on the right hardware). Not all hardware & drivers use the DRI, notably NVIDIA but their OpenGL on Linux is very fast, functional and binary compatible with apps calling using the standard ABI.

Latency will depend on your total transport delay buit 30ms doesn't sound too challenging unless the gltexsubimage really sucks on your hardware. The exact details of driver implementation is not your primary concern. Once you link to OpenGL using the standard ABI it will just work provided the system is configured correctly.