I added three image processing step to an OpenGL ES sample application provided by Apple.
What the application does is :
- Create OpenGL ES surface
- Load a color image
- In the rendering loop
1. Gray scale conversion from the original color image
2. Simple thresholding
3. Canny edge detection.
- Display 4 resulting images with texture mapping.
Well, after the image processing with OpenCV functions are added, the OpenGL ES application becomes much slower than before. Unfortunately I couldn't measure the exact frame rate of my application, but I feel that it is about 1 frame/sec.
Too slow huh ?
Update on 09/26/2009: Well, the frame rate is because of glTexSubImage2D I called in every frame to render the result and the size of image (I used 512x512 image).