Title: Printing performance enhancements for variable data publishing
Abstract: An apparatus for printing pages of a print job includes a page analyzer, a converting apparatus, an identifying apparatus, an optimizer apparatus, a storage apparatus, and a merging apparatus. The page analyzer is operative to identify static page aspects and variable page aspects from page data within a print job. The converting apparatus communicates with the page analyzer and is operative to convert the static page aspects into static page layout objects and the variable page aspects into variable print data. The identifying apparatus communicates with the converting apparatus and is operative to identify the static page layout objects in the manner allowing for an optimized form to be created, and to allow for appropriate merging with the variable print data. The optimizer apparatus communicates with the identifying apparatus and is operative to convert the static page layout objects to an optimized form. The storage apparatus communicates with the optimizer apparatus and is operative to store at least one instantiation of the static page layout objects in the optimized form. A merging apparatus communicates with the storing apparatus and is operative to merge the static page layout objects with the variable print data to create merged print data. A method is also provided.
Patent Number: 6,919,967 Issued on 07/19/2005 to Pentecost, et al.
| Inventors:
|
Pentecost; Robert E. (Boise, ID);
Pline; Steven L. (Eagle, ID)
|
| Assignee:
|
Hewlett-Packard Development Company, L.P. (Houston, TX)
|
| Appl. No.:
|
443684 |
| Filed:
|
November 18, 1999 |
| Current U.S. Class: |
358/1.15; 358/448; 235/375 |
| Intern'l Class: |
G06F 015/00; G06F017/00 |
| Field of Search: |
358/115,448,452,11
235/375,432
|
References Cited [Referenced By]
U.S. Patent Documents
| 4558302 | Dec., 1985 | Welch.
| |
| 4943936 | Jul., 1990 | Hirai et al.
| |
| 5129049 | Jul., 1992 | Cuzzo et al.
| |
| 5860073 | Jan., 1999 | Ferrel et al.
| |
| 5870464 | Feb., 1999 | Brewster et al.
| |
| 5915079 | Jun., 1999 | Vondran, Jr. et al.
| |
| 5923013 | Jul., 1999 | Suzuki et al.
| |
| 5940585 | Aug., 1999 | Vondran, Jr. et al.
| |
| 6204935 | Mar., 2001 | Soma et al.
| |
| 6330071 | Dec., 2001 | Vidyanand.
| |
| Foreign Patent Documents |
| 10124598 | May., 1998 | JP.
| |
| WO 99/2493/3 | May., 1999 | WO.
| |
Primary Examiner: Williams; Kimberly
Assistant Examiner: Ebrahimi-dehKordy; Saeid
Claims
1. An apparatus for printing pages of a print job, comprising:
a page analyzer operative to identify static page aspects and variable page aspects
from page data within a print job;
a converting apparatus communicating with the page analyzer and operative to
convert the static page aspects into static page layout objects and the variable
page aspects into variable print data;
an identifying apparatus communicating with the converting apparatus and operative
to identify the static page layout objects in the manner allowing for an optimized
form to be created, and to allow for appropriate merging with the variable print
data;
an optimizer apparatus communicating with the identifying apparatus and operative
to convert the static page layout objects to an optimized form, wherein optimization
level to create the optimized form is based on intended usage of the static page
layout objects by a user;
a storage apparatus communicating with the optimizer apparatus and operative
to store at least one instantiation of the static page layout objects in the optimized
form; and
a merging apparatus communicating with the storing apparatus and operative to
merge the static page layout objects with the variable print data to create merged
print data.
2. The system of claim 1 wherein the page analyzer resides within a printer.
3. The apparatus of claim 1 wherein the page analyzer resides within a printer server.
4. The apparatus of claim 1 wherein the optimizer apparatus removes the static
page layout objects that are not in an optimized form during the converting activity
in order to recover memory.
5. The apparatus of claim 1 wherein the merging apparatus includes a static page
buffer and a variable page buffer, the static page buffer capable of receiving
raster print data for the optimized form of the static page layout objects, and
the variable page buffer operative to receive raster print data for the variable
print data.
6. The apparatus of claim 5 wherein the merging apparatus is further operative
to convert the optimized form of the static page layout objects stored in the storage
apparatus to a raster form, and to convert the variable print data to a raster
form, the merging apparatus further operative to initialize the static page buffer
with the optimized form of the static page layout objects in the raster form and
thereafter to merge the optimized form of the static page layout objects with the
variable print data by transmitting the variable print data in the raster form
to the variable page buffer.
7. The apparatus of claim 1 wherein the static page aspects comprise static image elements.
8. The apparatus of claim 1 wherein the static page layout objects comprise forms.
9. The apparatus of claim 8 wherein a processed form comprises at least one layer.
10. A page printing apparatus, comprising:
a page analyzer operative to identify at least one static page aspect and at
least one variable page aspect within a print job;
a converting apparatus communicating with the page analyzer and operative to
convert the static page aspect into a static layer and the variable page aspect
into a variable layer;
an identifying apparatus communicating with the converting apparatus and operative
to identify the static layer in the manner allowing for an optimized form to be
created, and to allow for appropriate merging with the variable layer;
an optimizer apparatus communicating with the identifying apparatus and operative
to convert the static layer to an optimized form, wherein optimization level to
create the optimized form is based on intended usage of the static page layout
objects by a user;
a storage apparatus communicating with the optimizer apparatus and operative
to store at least one instantiation of the static layer in the optimized form;
and
a merging apparatus communicating with the storing apparatus and operative to
merge the static layer with the variable layer to create merged print data.
11. The page printing apparatus of claim 10 wherein the static layer is formed
from static page layout objects.
12. The page printing apparatus of claim 10 wherein the variable layer is formed
from variable print data.
13. The page printing apparatus of claim 10 where each of the static layer and
the variable layer comprise a process collection of page layout objects including
one or more of images, graphics, and text represented in a page description language.
14. The page printing apparatus of claim 10 wherein the storage apparatus is
configured to store the static layer for re-use by caching the static layer within
the storage apparatus.
15. A method for printing pages of a print job, comprising:
analyzing pages of a print job for static page aspects and variable page aspects;
creating print data by converting at least one instantiation of the static page
aspects into static page layout objects, and converting the variable page aspects
into variable print data;
identifying the static page layout objects in a manner allowing for an optimized
form to be created, and to allow for appropriate merging with the variable print
data;
converting the static page layout objects to an optimized form, wherein optimization
level to create the optimized form is based on intended usage of the static page
layout objects by a user;
storing at least one instantiation of the static page layout objects in the optimized
form;
merging the static page layout objects with the variable print data to create
appropriately merged print data; and
printing the merged print data.
16. The method of claim 15 wherein the step of merging comprises:
converting the static page layout objects to a raster form;
converting the variable print data to a raster form;
initializing a buffer device with the raster form of the static page layout objects;
and
transmitting the raster form of the static page layout objects to the buffer
device.
17. The method of claim 15 further including removing the static page layout
objects present in non-optimized form, following converting the at least one instantiation
of the static page aspects into the static page layout objects.
18. The method of claim 15 wherein the static page layout objects form a static
layer, and wherein the variable print data forms a variable layer.
19. The method of claim 18 wherein the step of storing at least one instantiation
of the static page layout objects comprises layer caching the static layer within
memory for later re-use.
20. The method of claim 15 wherein a plurality of the static page layout objects
together provide a form that includes one or more of images, graphics and text
represented in a page description language.
21. An apparatus for printing pages of a print job, comprising:
a page analyzer operative to identify static page aspects and variable page aspects
from page data within a print job;
a converting apparatus communicating with the page analyzer and operative to
convert the static page aspects into static page layout objects and the variable
page aspects into variable print data;
an identifying apparatus communicating with the converting apparatus and operative
to identify the static page layout objects in the manner allowing for an optimized
form to be created, and to allow for appropriate merging with the variable print
data;
an optimizer apparatus communicating with the identifying apparatus and operative
to convert the static page layout objects to an optimized form, wherein optimization
level to create the optimized form is based on intended use of the static page
layout objects by a user, and wherein individual ones of the static page layout
objects include a field indicative of the intended use by the user, the field being
used to determine the optimization level and to optimize storage of the static
page layout objects;
a storage apparatus communicating with the optimizer apparatus and operative
to store at least one instantiation of the static page layout objects in the optimized
form; and
a merging apparatus communicating with the storing apparatus and operative to
merge the static page layout objects with the variable print data to create merged
print data.
22. The apparatus of claim 9 wherein the preprocessed form comprises one or more
layers, and management of the one or more layers is performed by calling a file
system of a printer in order to manage resources of the printer.
23. The apparatus of claim 22 wherein caching of the one or more layers is performed
by establishing a link between individual ones of the layers and the static page
layout objects.
24. The apparatus of claim 23 wherein individual static page layout objects include
a field indicative of intended usage of the individual static page layout objects
by a user.
25. The apparatus of claim 24 wherein the field is used by a printer to optimize
storage of the static page layout objects.
26. The apparatus of claim 1 wherein the optimized form is preprocessed to create
one or more layers, wherein individual ones of the layers are used to create a
page configured for printing by a printer.
27. The apparatus of claim 26 wherein the individual ones of the layers are independent
of each other and are managed by the printer.
28. The apparatus of claim 26 wherein upon deletion of the optimized form, a
correspondingly created cached layer is also deleted.
29. The apparatus of claim 26 wherein upon renaming of the optimized form, links
to individual ones of the layers related to the optimized form are updated.
Description
FIELD OF THE INVENTION
This invention relates to computer systems and hard copy output devices, and
more particularly, to computers and page printers handling data with static page
aspects and variable page aspects.
BACKGROUND OF THE INVENTION
The resources and time required to print from an application program to a hard
copy output device can have a direct effect on a user's productivity as well as
the overall cost of a hard copy output device. As a result, there is a continuing
interest to develop techniques which improve printing performance of hard copy
output devices by reducing bottlenecks which affect the time it takes to print
a document from an application program. Additionally, there is a strong interest
to develop techniques which reduce the required memory resources of a hard copy
output device since such reduction will reduce the overall cost of the hard copy
output device.
For purposes of this disclosure, it is understood that a hard copy output device
comprises any device capable of generating output jobs, such as print jobs delivered
from a page printer, and including documents having one or more pages printed thereon.
For the case of page printers, a typical printer receives print data from a host
computer in the form of a printer control language data stream which is transmitted
over a standard interface extending between the host and the printer. The data
stream includes print function commands that are interspersed with print data.
One potential bottleneck that may affect printing time is the time it takes to
transmit a data stream from the host computer to a printer. Transmission time generally
increases as the amount of print data and printer resolution increases. By transmitting
common page print data only once to a printer, print job transmission time may
be reduced by reducing the amount of print data that is required to be transmitted.
The common page print data can then be stored in printer memory and thereafter
only unique page print data need be transmitted to the printer.
Common page print data are representative of common page aspects between pages
that are to be printed. U.S. patent application Ser. No. 08/936,568, entitled "Method
and Apparatus for Reducing Printer Memory", describes one technique for optimizing
the printing of various image elements across many pages. However, this technique
is limited to background image elements that are repeated on every printed page.
Such invention attempts to optimize the use of internal memory within a printer,
instead of optimizing the usage of images for repeated use. The terms "common page
aspects" and "unique page aspects" are illustrated in the above patent application,
which is incorporated herein by reference. One example of a common page aspect
is a common page background that includes background image elements that are repeated
on every printed page. One example of a unique page aspect is information which
varies between pages of a print job.
Within the art, there exist various printer control languages that allow for
identification of common page print data by using particular print function commands.
For example, Printer Control Language (PCL) forms the command language for Hewlett-Packard
LaserJet printers. PCL has become a de facto standard that is used in many printers
and typesetters. One commonly used printer control language, PCL Level 5, permits
common page print data to be identified by the use of a Macro 11 "Create Bitmap
of Macro" command. When such command is utilized, the common page print data is
rasterized, then stored into printer memory. Thereafter, the rasterized version
of the common page print data may be combined with unique page print data and printed
by use of the Macro 4 "Enable Macro for Overlay" command. Such commands are fully
described in the
PCL Implementors' Guide, Version 6.0, May 1, 1995, pp.
18-8 to 18-10, inclusive. Such pages are incorporated herein by reference as if
set out in full. Another commonly used printer control language, PostScript, has
somewhat similar capabilities by use of a "Copypage" command. Such command causes
the current rasterized page (e.g., a rasterized version of the common page print
data) to be combined with the next page (e.g., unique page print data) in the data
stream. Such command is described in the
PostScript Language Reference Manual,
Second edition, page 379. This page is incorporated herein by reference as if set
out in full.
Recent advances in printer capabilities, such as the addition of 24-bit color
capabilities, have increased the amount of print data required to represent a page.
As a result, various data compression techniques are used to reduce the memory
requirements, which also reduces costs, of these advanced printing systems. For
instance, U.S. Pat. No. 4,558,302 describes a well-known data compression technique
for printers. Such U.S. Pat. No. 4,558,302 is incorporated herein by reference
as if set out in full.
For the particular case where a print job includes many pages that have static
page aspects such as common image elements, there is a significant performance
penalty associated with carrying out such printing operation. More particularly,
a host computer is required to repeatedly send print commands and data for the
common image elements, for each page. Hence, the printer is required to repeatedly
render these common image elements when printing each page. As a result, a significant
amount of additional time is required to render such print job in the form of hard
copy output, such as a document. Additionally, a significant amount of computational
time and memory storage are concurrently required during such repeated rendering.
SUMMARY OF THE INVENTION
An apparatus and a method are provided for improving print performance by downloading
images that are static to a printer and holding such images, while variable data
is downloaded and merged with the static images in order to form a document. Such
an image can be formed by one or more image elements. A downloaded image element
may be a common background for a page, an image element for a fixed page position
but which is not used on every page, or an image element that may be placed anywhere
on a page, in any orientation or size.
According to one aspect of the invention, an apparatus for printing pages
of a print job includes a page analyzer, a converting apparatus, an identifying
apparatus, an optimizer apparatus, a storage apparatus, and a merging apparatus.
The page analyzer is operative to identify static page aspects and variable page
aspects from page data within a print job. The converting apparatus communicates
with the page analyzer and is operative to convert the static page aspects into
static page layout objects and the variable page aspects into variable print data.
The identifying apparatus communicates with the converting apparatus and is operative
to identify the static page layout objects in the manner allowing for an optimized
form to be created, and to allow for appropriate merging with the variable print
data. The optimizer apparatus communicates with the identifying apparatus and is
operative to convert the static page layout objects to an optimized form. The storage
apparatus communicates with the optimizer apparatus and is operative to store at
least one instantiation of the static page layout objects in the optimized form.
A merging apparatus communicates with the storing apparatus and is operative to
merge the static page layout objects with the variable print data to create merged
print data.
According to another aspect of the invention, a page printing apparatus
includes a page analyzer, a converting apparatus, an identifying apparatus, an
optimizer apparatus, a storage apparatus, and a merging apparatus. The page analyzer
is operative to identify at least one static page aspect and at least one variable
page aspect within a print job. The converting apparatus communicates with the
page analyzer and is operative to convert the static page aspect into a static
layer and the variable page aspect into a variable layer. The identifying apparatus
communicates with the converting apparatus and is operative to identify the static
layer in the manner allowing for an optimized form to be created, and to allow
for appropriate merging with the variable layer. The optimizer apparatus communicates
with the identifying apparatus and is operative to convert the static layer to
an optimized form. The storage apparatus communicates with the optimizer apparatus
and is operative to store at least one instantiation of the static layer in the
optimized form. The merging apparatus communicates with the storing apparatus and
is operative to merge the static layer with the variable layer to create merged
print data.
According to yet another aspect of the invention, a method for printing
pages of a print job is provided. The method includes analyzing pages of a print
job for static page aspects and variable page aspects, creating print data by converting
at least one instantiation of the static page aspects into static page layout objects,
and converting the variable page aspects into variable print data. The method also
identifies the static page layout objects in a manner allowing for an optimized
form to be created, and allowing for appropriate merging with the variable print
data. It also provides for converting the static page layout objects to an optimized
form, storing at least one instantiation of the static page layout objects in the
optimized form, merging the static page layout objects with the variable print
data to create appropriately merged print data, and printing the merged print data.
DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention are described below with reference
to the following accompanying drawings depicting examples embodying the best mode
for practicing the invention.
FIG. 1 is a high-level block diagram of an apparatus for printing print jobs
according to one aspect of the invention.
FIG. 2 is an abstract diagram illustrating an example of one page printed by
the apparatus of FIG. 2.
FIG. 3 is another abstract diagram illustrating an example of another page printed
by the apparatus of FIG. 2.
FIG. 4 is a logic flow diagram depicting a method for printing pages of a print
job having static page aspects and variable page aspects.
DETAILED DESCRIPTION OF THE INVENTION
This disclosure of the invention is submitted in furtherance of the constitutional
purposes of the U.S. Patent Laws "to promote the progress of science and useful
arts". U.S. Constitution, Article 1, Section 8.
This invention takes advantage of the use of static page aspects in the form
of static page layout objects to reduce print job transmission time, and further
adds the ability to store static page layout objects in an optimized form which
reduces memory requirements of a printer, thereby reducing overall cost of a printer.
A. Overview
Variable Data Publishing (VDP) is a mechanism to improve print performance
by downloading images and/or text that are static to a printer and holding them,
while variable data is downloaded and merged with the static images to form a document.
The image element that is downloaded may be a common background for a page, an
image element with a fixed page position but not used on every page, or an image
element that may be placed anywhere on the page, in any orientation.
Downloaded image elements are stored by the printer in an optimized form
that allows the image to be printed without requiring full rendering as is done
when a new image is received for each page. The downloaded image elements can be
saved in a variety of formats depending on how the image elements are to be used.
If an image is to be placed in a fixed location on a page, it can be optimized
to a very low level and placing it on the page requires little printer processing.
If the image can be placed in a variety of locations on a page, the optimization
is at a higher level.
For purposes of this disclosure, a static page layout object is an independent
block of data, text and/or graphics that have been created by an application, and
exist within a compound document. It is understood that static page aspects can
be formed by one or more static page layout objects. It is further understood that
a static page layout object can be formed by one or more image elements.
From a document point of view, one example of a very common static image is
a background that appears on every page that is to be printed. Once the background
is placed on the page, variable data is placed on the page. More advanced publishing
will allow a document to be created which selects images from a library, which
has been downloaded to the printer, to be placed in a document. Further enhancements
would allow those library images to be scaled and rotated.
The complexity involved in printing a color page has continued to increase. As
a result, the ability for a raster image processor to "rip" at the same speed at
which a printer engine runs has remained beyond the capability of mainstream printer
formatter technology. Two significant opportunities are available for increasing
print performance by implementing Applicant's invention. First, an ability is provided
to print documents using presentation graphics programs such as PowerPoint™
by Microsoft Corporation, of Redmond, Wash. Secondly, an ability is provided to
print Variable Data Publishing (VDP) documents. Documents which are generated using
these techniques have information that is repeated from page to page, within a
print job, and from print job to print job. The utilization of VDP technology according
to Applicant's invention will enable the printing of pages more quickly because
repetitive page elements are only processed once.
The implementation of Applicant's invention is beneficial to several potential
customers. For example, business office customers who typically create or print
PowerPoint™ presentations in color will be able to print a presentation
much more quickly where there exist static page aspects. Amateur and professional
customers who are in the business of generating creative print media, both in offices
and creative agencies, will now be able to produce customized color brochures,
newsletters, flyers and data sheets at previously unattainable levels of quality,
price and speed. Marketing departments for financial and other customer service
oriented industries will be able to produce transaction documents in color that
assist in the closing of sales in response to customer requests.
B. Terms
Compound document-A single document containing a combination of data structures
such as graphics, text, spreadsheets, sound and video clips. Additional data types
may be imbedded in the document, or external files may be referenced by pointers
of some sort. Hyper Text Mark-up Language (HTML), a document format used on the
World Wide Web, forms one example of a compound document format.
Form-A collection of page layout objects which may include images, graphics
and text represented in a PDL (Page Description Language).
Job-One or more pages which the user intends to keep together as a document.
Layer-A processed form saved in an intermediate state-somewhere between a
PDL format and video.
Layer caching-A process used to maintain a layer for re-use.
NVM-Non-volatile memory.
Object-An independent block of data, text and/or graphics that is created
by an application capable of generating a print job, and found within a compound document.
Page-An entire image provided on a single side of a piece of media.
PCL Forms-Technically, a printer control language (PCL) macro.
PCL Macro-A collection of PCL 5e/C or lower code which is downloaded to a printer
once and which can be called for repeated use.
Permanency-A length of time a resource is maintained by the system.
Resources may be maintained for a page, a job or in non-volatile memory indefinitely.
PostScript Forms Caching-A mechanism for saving PostScript Level 2 or
greater code to non-volatile storage in a printer.
PPI-Performance Printing Initiative. A technology for improving print
speed of documents with repetitive backgrounds.
Stream-A byte corrected sequence of operators and data.
Transaction based printing-Unique documents with a standardized or rule
based format which are printed as part of a business transaction such as a customer
service call, a 401 K plan change or a purchase of a product or service.
VDP (Variable Data Publishing)-A term which refers to a market opportunity of
printing unique or versioned documents for specific customers.
C. Preferred Embodiment
With reference to FIG. 1, a high-level block diagram is shown for a print job
apparatus incorporating the invention and identified generally by reference numeral
10. Apparatus
10 includes a host
12 which provides a source
for generating a print job that is delivered to a peripheral
14. According
to one construction, host
12 comprises a personal computer (PC). Also according
to one construction, peripheral
14 comprises a hard copy output device
18,
such as a page printer. It is understood that any of a number of different types
of page printers-can be utilized, such as impact printers, laser printers, inkjet
printers, solid ink printers, thermal wax transfer printers, electrostatic printers,
or any other printer capable of rendering images in the form of one or more pages
on a hard copy such as individual sheets of paper. It is further understood that
devices which include a page printer are also intended to benefit from Applicant's
invention, such as facsimile machines, multi-function peripherals (MFPs), copiers,
and network printers (which include a print server).
In order to illustrate this invention according to one embodiment, it is assumed
that computer
16 and printer
18 employ Printer Control Language (PCL),
a command language presently utilized by Hewlett-Packard LaserJet printers sold
by Hewlett-Packard Company, of Palo Alto, Calif. PCL is widely recognized as a
de facto standard used in many printers and typesetters. PCL Level 5 was initially
introduced in 1990. The utilization of PCL to illustrate Applicant's invention
is merely exemplary, and other printer control languages are contemplated.
Computer
16 includes a microprocessor
20, memory
22,
and a printer driver
24. According to one construction, memory
22
comprises Random Access Memory (RAM). As shown in FIG. 1, memory
22 includes
analyzing software
26 and an application program
28. Microprocessor
20 comprises processing circuitry
30. Computer
16 is interconnected
with printer
18 via a bus
32, by way of individual input/output (I/O)
ports
36 and
38, respectively. RAM
22 is configured to hold
software that controls certain aspects of microprocessor
20, including analyzing
software
26, as well as an application program
28 from which a print
job originates and is generated. Microprocessor
20 utilizes analyzing software
26 in order to perform several specific functions as described below.
More particularly, analyzing software
26 is used by microprocessor
20
in order to (1) analyze pages from an application (such as from application program
20) for static page aspects and variable page aspects; (2) converting an
instantiation of the static page aspects into static page layout objects, and converting
the variable page aspects into variable print data; and (3) identifying the static
page layout objects in a manner allowing for an optimized form of the static page
layout objects to be created.
Bus
32 comprises one of a local bus and a network bus, and is connected
via I/O ports
34 and
36 with computer
16 and printer
18,
respectively. Accordingly, I/O ports
34,
36 and bus
32 cooperate
to provide an interface capability between host
12 and peripheral
14.
Page printer
18 includes a microprocessor
42, memory
44
and
46, Variable Data Publishing (VDP) unit
62, and a print engine
52. According to one construction, memory
44 comprises Random Access
Memory (RAM). Also according to one construction, memory
46 comprises Read
Only Memory (ROM). RAM
44 includes two pre-allocation buffers: a static
page buffer
56, and a variable page buffer
58. The static page buffer
56 is configured for storing optimized static page layout objects, and the
variable page buffer
58 is configured for storing optimized variable print data.
Microprocessor
42 comprises processing circuitry
54
that provides a CPU on a single chip. ROM
46 includes page determination
software
60. VDP
62 includes a Multi-path Data Processing Pipeline
(MDPP)
48, where MDPP
48 includes a Date Merge Unit (DMU)
50.
In operation, page printer
18 receives a print request from computer
16
which is processed by processing circuitry
54 through unit
62 and
print engine
52 so as to generate hard copy output
38. Hard copy
output
38, according to one construction, comprises a multiple page document
40.
MDPP
48 provides converting functionality for converting static page
layout objects and variable print data to an optimized form. As defined here, static
page layout objects include forms and/or layers, and common page print data forms
one instance of static page layout objects. Similarly, unique page print data forms
one instance of variable print data. The internal operation of MDPP
48 is
described in U.S. Pat. No. 5,915,079 issued Jun. 22, 1999, and entitled "Multi-Path
Data Processing Pipeline". U.S. Pat. No. 5,915,079 is assigned to the same assignee
as the present application, and is incorporated by reference herein as if set out
in full. DMU
50 provides merging functionality for merging static page layout
objects, such as common page print data, with variable print data, such as unique
page print data. The internal operation of DMU
50 is further described in
U.S. Pat. No. 5,940,585 issued Aug. 17, 1999, entitled "Data Merge Unit". Such
patent application is also assigned to the same assignee as this application, and
is incorporated by reference herein as if set out in full.
According to one exemplary embodiment, page printer
18 is a color
laser printer that employs an electrophotography drum imaging system. However,
it is understood that page printer
18 can include any of a number of types
of hard copy output devices capable of generating hard copy output
38 upon
which print data is generated.
The use of MDPP
48 to convert static page layout objects to an optimized
form is merely exemplary. A printer employing other print data optimization techniques
can equally benefit from the present invention. For example, a printer which employs
print data optimization techniques described in the patent application entitled
"Method and Apparatus for Preventing Print Overruns", having U.S. Pat. No. 5,129,049,
could equally benefit from this invention. Such patent is incorporated herein by
reference as if set out in full.
Additionally, the use of DMU
50 to merge static page layout
objects and variable print data is also merely exemplary. For example, merging
may be accomplished at any storage device able to receive rasterized print data
or other types of page marking print data.
The operation of page printer
18 and computer
16, as shown in FIG.
1, commences with microprocessor
20, under the direction of analyzing software
26. Such operation performs the following four functions. First, pages are
analyzed (from an application originating from application program
28) in
order to determine static page aspects and variable page aspects. Second, the static
page aspects and variable page aspects are converted to static page layout objects
(comprising static print data) and variable print data, respectively. Third, a
data stream is created that is comprised of the static page layout objects and
variable print data. The data stream includes a header portion. According to one
construction, the data stream is rendered in PostScript. According to another construction,
the data stream is rendered in PCL. For the case where the data stream is rendered
in PCL, the header portion comprises a common page PCL escape sequence. The common
page PCL escape sequence identifies the static page layout objects. Fourth, the
data stream containing the identified static page layout objects and variable print
data is transmitted via I/O port
34, bus
32, and I/O port
36
to page printer
18.
According to one implementation, VDP
62 is implemented using PostScript
and existing PostScript commands. More particularly, each of the static page layout
objects is described in a form dictionary which includes a FormIntent field that
is unique to this specific implementation. The FormIntent field can be used by
the printer to optimize its storage of the original form dictionary data as well
as the cached image.
According to such a PostScript implementation for VDP
62, there
exists several primary considerations used to determine whether or not a FormIntent
field should be used, as follows. First, does the original form dictionary data
need to be saved? Secondly, is lower print quality acceptable in favor of higher
performance? Will the static page layout objects always be placed at the same location
on a page? Finally, is the static page layout object a background that can always
be placed first on a page?
For the case where the above four inquiries produce an affirmative result, utilization
of such a FormIntent field is desirable. The above is also generally true when
implementing VDP
62 via PCL-XL. More particularly, PCL5 is limited to macro
functionality. Furthermore, the process description which is set forth below will
be the same for PCL-XL and PostScript implementations. However, an exception to
this description would be when an image is formed and cached. For such case, it
could be when the printer receives the form, or it could be the first time the
form is executed, or placed onto a page.
The above-described PCL escape sequence represents an extension of the PCL language
developed for this implementation of the invention. Further details of such escape
sequence are described below. Unlike previous printer control language commands
for identifying static page layout objects, or more narrowly, common page print
data, the PCL escape sequence does not force the static page layout objects to
be stored in any particular form.
Microprocessor
42, under the direction of page determination
software
60 and ROM
46, scans the header portion of a received data
stream. Thereafter, microprocessor
42, in response to the detection of the
PCL escape sequence, determines the first page within the incoming data stream
as being static page layout objects. As a result of this determination, the static
page layout objects are extracted and sent to MDPP
48 for conversion to
an optimized form. After conversion, the static page layout objects, now in an
optimized form, are stored into static page buffer
56 in RAM
44.
According to a further aspect of the invention, microprocessor
42
transmits optimized static page layout objects and optimized variable print data
to MDPP
48 for merging. To accomplish merging, the optimized static page
layout object is first rasterized by MDPP
48. The rasterized static page
layout object is then appropriately transmitted to DMU
50. In this manner,
DMU
50 is initialized by the rasterized static page layout object. Previous
techniques for initializing a video buffer include transmitting a series of zeroes
to the video buffer. Each zero represents a white background pixel for the page
that is to be printed. Alternatively, as is pointed out above and claimed in the
present invention, the initialization of DMU
50 with rasterized static page
layout objects eliminates this step, and results in a more efficient process of
handling static page layout objects.
The variable print data is then also rasterized and transmitted to DMU
50.
Where a pixel of the rasterized static page layout object has the same address
as a pixel corresponding to the rasterized variable print data, the corresponding
pixels are merged appropriately from the rasterized static page layout object and
the rasterized variable print data. In this manner, a rasterized image is formed
with DMU
50 that represents the intent of a user for the first page. The
final and complete page is then printed by a print engine
52 to generate
hard copy output
38. This process is repeated for every additional page
within a print job such as individual pages of a document
40.
Turning now to FIGS. 2 and 3, exemplary hard copy output is shown for two
pages of a print job. More particularly, FIG. 2 illustrates a first page within
a print job, whereas FIG. 3 illustrates a second page within the same print job.
Each page comprises hard copy output (such as output
38 of FIG.
1).
More particularly, FIGS. 2 and 3 illustrate pages
64 and
66, respectively,
which are rendered on separate sheets of paper, and which form separate pages within
a specific print job. Alternatively, such pages can be generated by separate print jobs.
According to one example, each of pages
64 and
66 of FIGS.
2 and 3, respectively, contain print data in the form of a customer-specific automobile
sales brochure which has static page aspects and variable page aspects. More particularly,
the static page aspects are illustrated as layers
68 and
70 (in FIG.
2) and layers
68 and
72 (in FIG.
3). As previously described,
a layer is a process form that has been saved in an intermediate state, with a
form comprising a collection of page layout objects which may include images, graphics
and/or text. Accordingly, layers
68,
70 and
72 each comprise
static page layout objects. Additionally, pages
64 and
66 each include
variable page aspects in the form of variable print data
74 and
76, respectively.
As shown in FIGS. 2 and 3, layers
70 and
72 are identical in image,
but different in color, showing similarity in size and page placement, but illustrating
a different color between pages. Layer
68 forms a common background layout
comprising a common page aspect between pages
64 and
66. Variable
data
74 and
76 contain modifiable fields for a dealership customer
name, address, phone number and e-mail address. Such variable data can be customized
for printing of individual pages.
In operation, layers
68,
70 and
72 are variously combined
with variable data
74 and
76 prior to printing pages
64 and
66, respectively, according to the techniques illustrated pursuant to FIG.
4.
It is understood that another exemplary implementation includes utilization of
Applicant's invention to generate customizable real estate firm brochures containing
catalogues of properties for sale. Such utilization of stacked page aspects and
variable page aspects enables the customization of a real estate firm brochure
such that photographs of different properties can be placed in different spots,
depending on the projected interests of a prospective customer and/or audience.
Other implementations will be readily understood to be encompassed within the scope
of Applicant's invention, as defined by the appended claims.
According to one implementation, a page analyzer is provided by processing
circuitry
30 and analyzing software
26. A converting apparatus is
provided by processing circuitry
30, memory
22, and printer driver
24. An identifying apparatus is provided by processing circuitry
30,
printer driver
24, and analyzing software
26. An optimizer apparatus
is provided by a variable page buffer
58, page determination software
60,
MDPP
48, and static page buffer
56. A storage apparatus is provided
by static page buffer
56. Finally, a merging apparatus is provided by MDPP
48 and DMU
50.
D. Example
A Variable Data Publishing (VDP) architecture does not require the generation
of
new PCL5e/C or PostScript or PCL_XL commands. Instead, all communications between
the driver and printer can be managed using existing commands. When a VDP concept
is implemented in applications, users will realize a transmit-once performance
advantage for both legacy products (i.e., products that have been in existence
for some time) and future products. Future products that use PPI and VDP technologies
according to Applicant's invention will boost performance even more by reducing
processing for repetitive elements. PPI is one initial implementation of VDP and
allows a single layer to be created and overlaid as a background. Details of PPI
are disclosed in Applicant's co-pending U.S. patent application Ser. No. 08/936,568,
entitled "Method and Apparatus for Reducing Printer Memory", previously incorporated
by reference. Forms are pre-processed to create layers which can be stacked to
create a final page. Additionally, interaction between layers is not a part of
the architecture. Furthermore, layers are independent with transparent backgrounds
and opaque foregrounds. Such layers are internal to the printer, and cannot be
managed by-external software. Instead, all layer management is indirectly accomplished
through calls to a printer's file system in order to manage resources.
According to one implementation of layer caching, a link is established
between a layer and a saved form. When a form is called, the system will check
to see if a pre-processed version (or layer) exists. If a layer does not exist,
one is created and linked to the form. When a form is deleted, the cached layer
is also deleted. When a form is re-named, the link to the layer is updated by firmware.
The concept of forms works well for applications that hand roll PostScript. However,
GDI does not yet have a concept of forms. Therefore, developers who wish to access
forms capabilities through drivers that use such applications, for example, present
Hewlett-Packard drivers set up for Microsoft operating systems, will need to implement
a new set of escape sequences until a concept of forms is incorporated into GDI.
Forms and layers may be saved in a printer's non-volatile memory. The format
of the saved information depends on the future requirements for printing the form
and the printer's architecture. For example, a fixed-position form may be kept
as a layer in a device-specific-bits format, whereas a scalable form may need the
original PDL to be saved.
E. Target Applications
For the business office, Microsoft (MS) PowerPoint™ is a primary target
that can benefit from use of Applicant's invention. MS Publisher is second on the
list, followed by the remaining MS Office suite of applications. Since GDI does
not have a concept of forms, escapes will be used to signal printer drivers, which
will then insert PDL specific forms commands to be sent to the printer.
For the creative office and creative professional, QuarkXPress and Adobe K2 form
two primary applications that would benefit from use of Applicant's invention.
QuarkXPress is a desktop publishing program for MacIntosh and Windows that is available
from Quark, Inc., of Denver, Colo. Additional information is available at their
website, www.quark.com. AdobeK2 is a similar program available from Adobe Systems,
Inc., of Mountain View, Calif. Additional information is available at their website,
www.adobe.com. Support for these applications will be provided through variable
data extensions to the page layout applications. Presently, PostScript is the only
page description language (PDL) of record for these applications. Extension developers
are responsible for incorporating the PostScript forms caching commands required.
Transaction based printing is a secondary target application. Third-party
print stream enhancers will have access to development units and software developers'
kits (SDKs) through a Peripheral Developers Program.
F. Firmware Requirements
According to one exemplary implementation, firmware requirements are identified
below wherein the firmware comprise memory chips capable of holding content without
electrical power such as ROM, PROM, EPROM and EEPROM. Firmware becomes "hard software"
when holding program code. Exemplary details of specific functions are described
below with respect to such one embodiment.
Functions
1. Receive Form Data (header, data, and trailer).
- a. Header
- (1) Identifier (Alphanumeric ID). Up to 32 bytes (31 characters
plus a null terminator).
- (2) Desired Persistence (permanent, document or page).
- (3) Position (fixed or variable). If fixed position, the form contains
absolute positioning information and will always be printed on the page where the
first dot of the form is placed. If variable position, the form is placed according
to position information in the form execution command.
- b. PDL Data
- (1) Positioning information is included and may be absolute for
a fixed position form (e.g., for a background image) or relative to the current
position for a variable position form (e.g., to place an image anywhere on the page).
- (2) May contain raster image, vector data or text. While raster
images will overlay previously placed data, previously placed images will show
through text.
- c. Trailer
- (1) Indicates end of form data. At this point the printer may convert
the form to an optimized format or it may wait until a more appropriate time (e.g.,
when the form is first executed). The form's PDL data may be discarded if future
executions of the form can be performed from the optimized data (i.e., the form
image can be rendered on both side of duplex pages (regardless of binding), on
different type of media, with different half-tone patterns induced by printer calibration
or for printer-based N-up printing).
2. Execute Form. This occurs when the variable data portion of the job indicates
a form with a particular identifier is to be placed on the page. The form is overlaid
on the page regardless of previously placed images.
- a. Convert form data to a performance optimized printer-dependent layer
(if not done previously).
- (1) The layer is created based on the current state of the printer.
- (2) The layer is saved for future use, allowing the form interpretation
time to be avoided.
- (3) The layer may be deleted due to space constraints, providing
the original form data is kept.
- b. Return the state of the printer to pre-form execution state.
3. Delete Form Data.
- a. According to persistence.
- b. Selective deletion, by identifier, according to commands within the job/document.
- c. Management of permanent forms by software utilities. The form to
be deleted is indicated by ID.
G. Software Requirements
Further according to the one exemplary embodiment which incorporates the
exemplary firmware requirements above, software requirements are defined below
for such exemplary embodiment. More particularly, examples are given for escapes,
application support, and printer driver requirements.
Escapes
Applicant has defined the following escapes and structure for supporting
PPI with application support:
ESCAPES-BEGINFORMDEF, ENDFORMDEF, EXECFORM, REMOVEFORMDEF
STRUCT-FORM_STRUCT.
Application Support
Pursuant to a VDP Windows driver implementation, the PC software/application
requirements for a performance printing initiative (PPI) according to one exemplary
implementation are described below.
Applications such as Microsoft PowerPoint™ from Microsoft Corporation,
of Redmond, Wash., should support specifying a background once, and then have the
ability to reuse it. Without such application support in the future, it is all
but pointless to provide a PPI solution. For an application to support PPI it should
implement the steps as defined in the following example:
EXAMPLE
Steps in Setting Up A Form/Background
- 1. Call QUERYESCSUPPORT to find out if the device supports the required
form escapes. A query on any one of the escapes-BEGINFORMDEF, ENDFORMDEF, EXECFORM,
REMOVEFORMDEF will guarantee that the other three escapes are supported.
- 2. Call BEGINFORMDEF escape with the desired persistence, source width
and height and destination width and height.
- 3. Send the form/background data through normal APl's. All printable
data (text, bitmaps, line drawing) and graphics state changes are valid in a form/background.
- 4. Call ENDFORMDEF escape after all of the form/background data has
been sent. This will signal the driver that you are done defining the form.
- 5. Keep track of the name and the persistence the printer driver returns
from ENDFORMDEF.
- 6. Call EXECFORM every time you want to place the form/background on
the page. Provide the form/background name returned by ENDFORMDEF and the (x,y)
position of the upper/left corner of where to place the form/background.
Forms can be defined (BEGINFORMDEF and ENDFORMDEF) any time in the document
before they are used. Deleting forms (REMOVEFORMDEF) can be executed any time except
between a BEGINFORMDEF-ENDFORMDEF pair.
A call to the escape GETFORMSUPPORT will provide the supported form/background
coordinate transformations for the printer.
If any part of the background changes the driver is responsible for sending down
