Design rule for Camera File system

Design rule for Camera File system (DCF) is a JEITA specification (number CP-3461) which defines a file system for digital cameras, including the directory structure, file naming method, character set, file format, and metadata format. It is currently the de facto industry standard for digital still cameras. The file format of DCF conforms to the Exif specification, but the DCF specification also allows use of any other file formats.

The latest version of the standard is 2.0 (2010 edition).

In order to guarantee interoperability, DCF specifies the file system for image and sound files to be used on formatted DCF media (like removable or non-removable memory) as FAT12, FAT16, FAT32, or exFAT. Media with a capacity of more than 2 GB must be formatted using FAT32 or exFAT.

The DCF standard defines that the "Read Only" file and directory attribute of FAT file systems can be used to protect files or directories from accidental deletion. Other existing attributes don't have any specially defined usage in DCF.

The filesystem in a digital camera contains a DCIM (Digital Camera IMages) directory, which can contain multiple subdirectories with names such as "123ABCDE" that consist of a unique directory number (in the range 100…999) and five alphanumeric characters, which may be freely chosen and often refer to a camera maker. These directories contain files with names such as "ABCD1234.JPG" that consist of four alphanumeric characters (often "DSC_", "DSC0", "DSCF", "IMG_", "MOV_", or "P000"), followed by a number. DCF 2.0 adds support for DCF optional files recorded in an optional color space (that is, Adobe RGB rather than sRGB). Such files must be indicated by a leading "_" (as in "_DSC" instead of "DSC_" or "DSC0").

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