JEITA CP-3451 Explication - 138 - 7.3.4    Flash Tag Information This tag indicates the flash status when the picture was taken. [Writer] �|The red-eye bit indicates whether the flash was fired for the purpose of red-eye reduction, including pre-flash. [Reader] �|This tag can be used along with subject distance range (or subject distance), scene type and brightness to determine whether suitable exposure is possible. 7.3.5    SubjectArea Tag Information This tag indicates the location and area of the main subject in the overall scene. [Writer] �|The writer should record a subject area that is large enough to enable the reader to determine the subject, preferably at least one percent of the total image area. [Reader] �|A reader can refer to this information as the area for image optimization processing. 7.3.6    CustomRendered Tag Information This tag indicates the use of special processing on image data, such as rendering geared to output. When special processing is performed, the reader is expected to disable or minimize any further processing. [Writer] �|For ordinary shooting this is set to 0 (normal process). If the writer applies special processing such as monochrome mode or sepia mode, and it is desired to prevent or minimize automatic adjustment by the reader, a value of 1 is set (custom process). [Reader] �|When a value of 1 (custom process) is set, the reader determines that the image has already been specially processed, and should either disable or reduce any further processing in order to prevent double processing. 7.3.7    ExposureMode Tag Information This tag indicates the exposure mode set when the image was shot. [Writer] �|If shutter speed and aperture were set by the user, the writer sets a value of 1 (manual exposure); if auto-bracketing was set, a value of 2 (auto bracket) is recorded.   �|When exposure bias was set, it is up to the writer whether to record 0 (auto exposure) or 1 (manual exposure).   [Reader] �|When a value of 0 (auto exposure) is set, a reader should perform automatic adjustment of exposure settings. �|When a value of 1 (manual exposure) or 2 (auto bracketing) is set, the reader should either not perform automatic bias or should reduce the amount of bias.