I am doing a image processing project. The image processing is implementing using glsl and rendering to a offscreen frame buffer. And then the 2D texture is using to update to the screen.
I am using Intel Atom E3845 processor.
My glsl shader of the image processing algorithm takes about 20ms for each 800*600 frame. My problem is the frame rate of the application is about 20fps which means that it takes about 50ms for each frame to show on the screen. So why it takes 30ms more time than the process time to show on the screen?
Can anyone tell me what is the problem? all the processing and update is in the same thread.