Image Access Qualifiers

Access Qualifiers for image memory objects.

__read_only __write_only read_only write_only

Description

Image memory objects specified as arguments to a kernel can be declared to be read-only or write-only. A kernel cannot read from and write to the same image memory object. The __read_only (or read_only) and __write_only (or write_only) qualifiers must be used with image memory object arguments to declare if the image memory object is being read or written by a kernel. The default qualifier is __read_only.

Example

In the example below, imageA is a read-only image memory object and imageB is a write-only image memory object.

__kernel void foo (read_only image2d_t imageA, write_only image2d_t imageB) { ... }

Specification

OpenCL Specification

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