IraqiGeek's Blog

Using a PS3 for raw image conversion

Earlier this year, I did some reading about the IBM-Sony-Toshiba Cell processor architecture, with its eight SPE (Synergistic Processing Elements). Like I said in a previous post, I believe that the Xbox360 tripple core PowerPC processor has more appeal for general purpose applications, but now that I am working on digital image processing applications, the two Cell processors inside Sony’s Play Station 3 console start to look really appealing. There are quite a few reasons why a PS3 would rock if used to carry the heavy procesing required in digital image processing such as raw conversion and photo retouching.

First, such applications lend themselves very well to heavy multithreading since most of the processing is simply running one or more functions iteratively on each pixel, so adapting code to run on the Cell’s SPE units shouldn’t be a complicated task. Second, The fact that each SPE has its own high speed local memory that is accessible and addressable by the softwre running on the main PPE (Power Processor Element) PowerPC core means that the application can quite easily load the image data they want to each of those processing elements.

Now, even with two Cell processors on board the PS3, I doubt the computation power would be anything close to what your average Geforce 7 or ATI 1xxx series graphics card can deliver. However, those SPEs inside the Cell processor should be much easier to program, like I said because each has its own memory that the application running on the PPE core can access and program.

Now that we have Linux running on the PS3, it would be interesting to see someone port, or create things like image processing, audio and/or video transcoding applications that can take advantage of the considerable amount of processing power that all those SPE units have to cut down processing times.

Why am I concerned? Because I started working on an application that allows photographers to adjust raw digital images prior to debayering/demosaicing those images to full RGB. Since then, my work expanded into the raw conversion process itself, where I managed to come with my own debayering algorithm. I am still working on adding support for the various camera makers raw file formats but hope to get the chance to port my code to something like a PlayStation 3 which would allow my application to execute several times faster than any x86 desktop or workstation available today and probably anytime in the next year, if not more.