Book Image

OpenCL Programming by Example

Book Image

OpenCL Programming by Example

Overview of this book

Research in parallel programming has been a mainstream topic for a decade, and will continue to be so for many decades to come. Many parallel programming standards and frameworks exist, but only take into account one type of hardware architecture. Today computing platforms come with many heterogeneous devices. OpenCL provides royalty free standard to program heterogeneous hardware. This guide offers you a compact coverage of all the major topics of OpenCL programming. It explains optimization techniques and strategies in-depth, using illustrative examples and also provides case studies from diverse fields. Beginners and advanced application developers will find this book very useful. Beginning with the discussion of the OpenCL models, this book explores their architectural view, programming interfaces and primitives. It slowly demystifies the process of identifying the data and task parallelism in diverse algorithms. It presents examples from different domains to show how the problems within different domains can be solved more efficiently using OpenCL. You will learn about parallel sorting, histogram generation, JPEG compression, linear and parabolic regression and k-nearest neighborhood, a clustering algorithm in pattern recognition. Following on from this, optimization strategies are explained with matrix multiplication examples. You will also learn how to do an interoperation of OpenGL and OpenCL. "OpenCL Programming by Example" explains OpenCL in the simplest possible language, which beginners will find it easy to understand. Developers and programmers from different domains who want to achieve acceleration for their applications will find this book very useful.
Table of Contents (18 chapters)
OpenCL Programming by Example
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Platform versions


The OpenCL is designed to support devices with different capabilities under a single platform. This includes devices which conform to different versions of the OpenCL specification. While writing an OpenCL based application one needs to query the implementation about the supported version in the platform. There are mainly two different types of version identifiers to consider.

  • Platform Version: Indicates the version of the OpenCL runtime supported.

  • Device Version: Indicates the device capabilities and attributes. The conformant version info provided cannot be greater than platform version.

Query platforms

Now let's write an OpenCL program to get the platform details. Use the get_platform_property example in this chapter.

The OpenCL standard specifies API interfaces to determine the platform configuration. To query the platform versions and details of the OpenCL implementation, the following two APIs are used:

cl_int clGetPlatformIDs (cl_uint num_entries,
  cl_platform_id *platforms...