A few months ago, I suggested that Raspberry Pis could be used as a barebones experiment presentation machine. Since then I have got my hands on one and tinkered a little, only to be reminded yet again that my inability to do anything much in both Linux and python is a bit of a problem.
Fortunately, others with more technological nous have been busy exploring the capabilities of the Pi, with some exciting findings. On the Cognitive Science Stack Exchange, user appositive asked “Is the Raspberry Pi capable of operating as a stimulus presentation system for experiments?” and followed up at the end of January with a great answer to their own question, including this paragraph:
The RPi does not support OpenGL. I approached this system with the idea of using a python environment to create and present experiments. There are two good options for this that I know of, opensesame and psychopy. Psychopy requires an OpenGL python backend (pyglet), so it won’t run on the Rpi. Opensesame gives you the option of using the same backend as PsychoPy uses but has other options, one of which does not rely on openGL (based on pygames). This ‘legacy’ backend works just fine. But the absence of openGL means that graphics rely solely on the 700 mHz CPU, which quickly gets overloaded with any sort of rapidly changing visual stimuli (ie. flowing gabors, video, etc.).
Because of the lack of OpenGL support on the Pi, Psychopy is out (for now) leaving OpenSesame as the best cog psych-focused python environment for experiment presentation. The current situation seems to be that the Pi is suboptimal for graphics-intensive experiments, though this may improve as hardware acceleration is incorporated to take advantage of the Pi’s beefy graphics hardware. As things stand though, experiments with words and basic picture stimuli should be fine. It’s just a case of getting hold of one and brushing up on python.
UPDATE via Comments (1/4/2013) – Sebastiaan Mathôt has has published some nice Raspberry Pi graphics benchmarking data, which are well worth a look if you’re interested.