Exploiting image processing locality in cache pre-fetching

Emerging trends in computer design attempt to include specific solutions for handling images also in general-purpose computers, because of the current spread of multimedia, image processing and computer graphics applications. In this context, this paper proposes hardware pre-fetching techniques specific for caching images: the main issue we state is that most algorithms working opt images exhibit a 2D spatial locality that is not taken into account in current cache organization and data access strategies. To this aim we propose an adaptive local pre-fetching for the image data type; this technique, mirroring the two-dimensional spatial locality of image processing algorithms, results to be more efficient than other approaches, such as sequential pre-fetching and adaptive pre-fetching. Performance is evaluated on different classes of image processing algorithms, namely raster-scan and propagative algorithms, common in computer vision and multimedia applications.