Cognitive Solutions A776, B780 Define/Update Application Tag Values, Decimal Value, Return None

Chapter 5: Programming commands  135

Define/Update Application Tag Values

Hexadecimal: 1D B4 nL nH t0 . . .tm

Parameters: n is the total byte count size of user TagData structures, each structure is similarly defined in the TIFF

specification: 2 byte tag value, followed by a 2 byte type value, followed by a 2 byte count of byte length (note: this differs from TIFF directory entry), followed by the object. If the object is a string type, this would be the string itself; max length of each string is 127.

t0…tm are the tag structures. If the byte length is 0 then that non-reserved (Application) tag is eliminated from being set on future scanned images.

n is limited to 256 maximum parameter data length size, so if the total tag structures to be set exceed that, then they should be divided and sent as multiple commands; n = 0 is used to erase all application set Tags.

Return: None

Description: The application set image tag values are saved for use with any future documents scanned, which will also be identified by an automatically generated numerical File Index tag. If any non-automatically generated tags are application set, they will be copied into the TIFF header along with the automatically generated ones. All tags will be returned in the TIFF structure whenever one or both bottom and top scanner images are transmitted. While only the tags identified as “reserved” will be set by firmware, it is suggested that the application use tag numbers as specified in the TIFF standard which provides for privately defined usage of tags above 32,768.

Tags noted as “application initialized” can be sent and will be updated by the firmware, for example date-time.

Using the following suggested pertinent “application” tag numbers insures there will be no misuse of TIFF predefined numbers. Do not use any of the reserved, FW generated numbers – that data will be automatically overwritten at each scan by the firmware. Values are in decimal corresponding to those in the TIFF specification:

Decimal Value	Definition
254	Reserved for FW auto generated int: Subfile Type =0 one side, =2 both
256	Reserved for FW auto generated int: Image Width
257	Reserved for FW auto generated int: Image Length
258	Reserved for FW auto generated int: Bits Per Sample (either 1, 4, or 8)
259	Reserved for FW auto generated int: Image compression format
262	Reserved for FW auto generated int: Photometric Interpretation, 0=White is zero when format =
	T6.G4 binary, else 1=Black is Zero
269	Application supplied string: Document Name (= UPOS “FileID”)
270	Application supplied string: Image Description (= UPOS “UserTag”)
271	Application supplied string: printer Make description
272	Application supplied string: printer Model description
273	Reserved for FW auto generated int: Strip Offsets
278	Reserved for FW auto generated int: Rows Per Strip
279	Reserved for FW auto generated int: Strip Byte Counts
282	Reserved for FW auto generated rational: X Resolution (given as 200 / 1)
283	Reserved for FW auto generated rational: Y Resolution (given as 200 / 1)
285	Application supplied Page Name (repeated if have both top and bottom images; suggest use as
	Transaction ID)
293	Reserved for FW auto generated int: T6 Options (=0)
296	Reserved for FW auto generated int: = 2 (pixels expressed per inch)

Continued . . .

A776-PG00001 C 12/09 A776 (B780) Programming Guide