This extension enables kernels to write to sRGB images using the imageWriteFunctions[write_imagef] built-in function. The sRGB image formats that may be written to will be returned by clGetSupportedImageFormats.
When the image is an sRGB image, the imageWriteFunctions[write_imagef] built-in function will perform the linear to sRGB conversion. Only the R, G, and B components are converted from linear to sRGB; the A component is written as-is.
For more information, see the OpenCL Extension Specification at URL