2d graphics library (*nix)

[Talguy]

I am revisiting my EE senior design project that I finished up about 8 months ago. We basically took your vehicles instrument cluster and replaced it with a computer and graphically rendered your vehicles metric with the help of a datalogger. For the graphics I used cairomm for its vector graphics and ability to draw png files to the canvas. I also used gtkmm for the drawing canvas and its interrupt functions. Our final product we could only crank out 6.5 frames a second. I am currently trying add some features that we did not get too but I want to be able to draw a minimum of 20 frames a second to the screen. Does anyone know of another graphics library other than OpenGL for linux that can do 2d graphics and draw png files to the screen much faster than cariormm. If not does anyone know any good optimization tips for using the cairo graphics library.