• EXIF_DATA_OPTION_DONT_CHANGE_MAKER_NOTE : exif-data.h
• EXIF_DATA_OPTION_FOLLOW_SPECIFICATION : exif-data.h
• EXIF_DATA_OPTION_IGNORE_UNKNOWN_TAGS : exif-data.h
• EXIF_SUPPORT_LEVEL_MANDATORY : exif-tag.h
• EXIF_SUPPORT_LEVEL_NOT_RECORDED : exif-tag.h
• EXIF_SUPPORT_LEVEL_OPTIONAL : exif-tag.h
• EXIF_SUPPORT_LEVEL_UNKNOWN : exif-tag.h