Tuesday, June 4, 2013

More optimizations required

Well, I got the JPEG decoding speed running very fast.  However, once I add in some game-generated video overlay, performance drops from 100 FPS down to 85 FPS.  This was a bit of a red flag for me since OpenGL is supposed to be, well, fast!

So I am making a goal to get performance back up to over 95 FPS (or better) with the overlay active.  I've found some areas of potential optimization that I can do.

UPDATE: Success!


  1. I'm trying to display a large JPG really quickly on the RPi, however my C skills are pretty much non-existent... so for now I'm tinkering with Python and just calling FBI. Do you have any suggestions or pointers to a quick way to render a JPG to the screen? - Mike.

    1. Ok, I published my code and posted about it here:

      Unfortunately, I am not getting much response. If you could respond to this thread to help draw attention to this, I'd appreciate. I think this is something a lot of pi devs would be interested in.

  2. I think using only OpenMAX is probably the fastest way to render a JPG to the screen, but I don't like that because it is inflexible. My approach of using OpenMAX and GLES2 to render a JPG is probably slightly slower but infinitely more flexible. I may try to put together some source code for people since I can see there is some interest. It won't be python though.