Heterogeneous Computing with OpenCL, 2nd Edition

Chapter 8

OpenCL Case StudyConvolution

Introduction

In Chapter 4, we introduced a basic convolution example using OpenCL images. Images provided the benefit of automatically handling out-of-bounds accesses (by clamping or wrapping accesses), which simplified the coding that would have been required for the cases in which the convolution filter accessed data outside of the image. Thus, image support may reduce control flow overhead and provide caching and data access transformations that improve memory system performance. When targeting GPUs, the automatic caching mechanism provided for images is much better than not caching. In many circumstances, however, it can be outperformed by efficient use of local memory. In this chapter, we use a convolution ...