ijpds formats.book - Kodak

Chapter 1. Overview
Configuring Stitched RIPs
Configuring Stitched RIPs
Image Positions (X and Y)
1 - 6 IJPDS Formats
Some printing systems with multiple printheads contain multiple,
physically separate RIPs in the same data station. The page buffers for
each RIP represent the width of the printhead. Two or more RIPs can be
treated as a combined, single RIP, called a super RIP and the resulting
page buffer is as wide as the number of printheads. (For example, the
page buffer for each 4-inch printhead RIP is 1024 bits by 4096 bits. If the
RIPs for two 4-inch printheads are treated as a super RIP, data is sent to
the super RIP as if the page buffer were 2048 dots wide.)
The PLR may be used to make the length of the buffer longer than these
defaults if a long document requires it, at the expense of font memory.
Using a PLR to call for the RIP to be shorter than the default has no
effect. There is no appreciable impact on performance with a change in
PLR value.
When two or more RIPs are stitched, the IJPDS file should be built as if
there were a single larger RIP. If you want four 4-inch printheads to be
stitched, you configure the data for one 17-inch RIP and the operator
must configure the controller and data stations to stitch the four
printheads/RIPs after which the data stations will all be sent the 17-inch
data and each RIP will print its 4-inch (1024-dot) “slice”, clipping the parts
that “fall off” either side. This 17-inch logical RIP is called a super RIP.
Presently the equipment will not configure this automatically from the
stitched RIP indicator bits, but some future system might, so the job
should be described the job correctly, both in these bits and in the PHR
records (where you indicate there are four 1024-bit heads, and their
positions, in the 17-inch RIP).
You should also produce some sort of setup document for the operator,
as operators cannot easily determine the desired configuration from what
the controller tells them when they load the job.
Since you send stitched-RIP data as one larger RIP, the IJPDS proofer
software shows it as if it were one larger RIP, but it is possible in proofer
version 3.1 and above to use Show Stitch Lines in the View menu, or the
corresponding toolbar button, to show the stitch lines (in red) for purposes
of determining what printed data may be running across the stitch.
An image is a pattern of filled and unfilled dots. It can be a character, a
line of characters, or a graphic. Position records within the IJPDS job file
specify starting positions on the document for the image data that follows.
A starting position is defined by X and Y coordinates and can be absolute
or relative.
The cursor position at the start of a document is set to the upper left
corner of the document as viewed from the printhead looking in the
direction of substrate movement. As shown in Figure 1.5, the X,Y
coordinates for the upper left corner of the document are 0,0, which is the
cursor origin position. If a set origin record (SOR) occurs somewhere on
the page, the origin is reset to the current cursor position.