ISO 14524:2009

ISO 14524:2009 specifies methods for the measurement of opto-electronic conversion functions (OECFs) of electronic still-picture cameras whose output is encoded as a digital image file. The OECF is defined as the relationship between the focal plane log exposures or scene log luminances, and the digital output levels of an opto-electronic digital image capture system.
ISO 14524:2009 applies to both monochrome and colour electronic still picture cameras.