DDST

DDST Format Description for the Ricoh C240DN printer

----preliminary---

Copyright by Malte Sartor, 2015 ([email protected]).
Licensed under CC BY-NC-SA (https://creativecommons.org/licenses/by-nc-sa/4.0/)

-----------------------------------------------------------------------
|   GDIJ - job information: filename, papertype, probably tray        |
-----------------------------------------------------------------------
|   GJET - user information: pc name and username                     |
----------------------------------------------------------------------|
|    --------------------------------------------------------------   |
|N x | GDIP - one for each page: amount of bands, paper size, etc |   |
|    |     ––––––––––––––––––––––––––––––––––––––––––––––––––     |   |
|    | N x |GDIB - actual image band                        |     |   |
|    |     --------------------------------------------------     |   |
|    --------------------------------------------------------------   |
-----------------------------------------------------------------------
|   JIDG - end of job marker                                          |
-----------------------------------------------------------------------



Blocks
GDIJ: Job Destriction
GJET: User Description
GDIP: Parameters??
GDIB: Image Data
JIDG: Job End marker

GDIB Description

For CMYK Print, GDIB consists of a Global Header and 4 Parts, for each Toner Color.

The Header (hex):
47 44 49 42 00 00 00 00 00 00 01 F4 00 00 03 14 00 00 04 B4 00 00 05 54 13 00 01 00 00 00 00 00
- Magic --- --DWORD 1-- --DWORD 2-- ---DWORD 3- ---DWORD 4- ---DWORD 5- WORD1 WORD2 --Zeroes---

DWORD 1:
1 For first GDIB
2 for last GDIB
0 for all other

DWORD 2:
length in bytes of K

DWORD 3:
length of C

DWORD 4:
length of M

DWORD 5:
length of Y

WORD 1:
Pixel Width of Image Data

Word 2:
Pixel Height of Image Data. Always 256, except the last GDIB, which is fitted to the printout length.

This is followed by 4 Segments of JBIG Data, each for KCMY.
They are zero padded to a length of at least 32byte or a by 4 dividable length.
At least one byte padding is added.
 pbmtojbg -q -l 0 -p 64 -m 0 -t 1 -s 256 generates compatible JBIG binaries.

BW GDIB blocks are completely the same, only the lenght of CMY are zero, and the JBIG Blocks for CMY are omitted.


GJET

0x00: GJET magic word
0x04: GJET total byte count: 168 [4]
0x08: Client Station Name [40]
0x48: Client User Name [40]
0x88: Zeros


GDIJ

0x00: GDIJ magic word [4]
0x04: GDIJ total byte count: 120 [4]
Rest unknown, most likely contains, somehow coded, the tray and paper thickness in

GDIP

0x00: GDIP magic word [4]
0x04: GDIP length: 128 [4]
0x08: Paper format [1] 1=Letter, 9=A4, more to follow.
0x0c: Dots width [2]
0x0e: Dots height [2]
0x20: Color count, 1 or 4 [1]
0x21: Duplex control: 1=no duplex, 0d= take page from tray, and keep for duplexing, 05= take kept page
0x22: Page Count, first page is 0, second 1 and so on [2]
0x27: Count of GDIB Blocks for this GDIP
0x38: Paper width in um [4] (or more likely printed area)
0x3c: Paper height in um [4]