U.S. patent application number 15/142941 was filed with the patent office on 2017-11-02 for method and apparatus for generating a multi-layer correlation mark via a monochrome printer.
The applicant listed for this patent is Xerox Corporation. Invention is credited to Edward CHAPMAN.
Application Number | 20170318183 15/142941 |
Document ID | / |
Family ID | 60157621 |
Filed Date | 2017-11-02 |
United States Patent
Application |
20170318183 |
Kind Code |
A1 |
CHAPMAN; Edward |
November 2, 2017 |
METHOD AND APPARATUS FOR GENERATING A MULTI-LAYER CORRELATION MARK
VIA A MONOCHROME PRINTER
Abstract
A method, non-transitory computer readable medium and apparatus
for generating a multi-layer correlation mark via a monochrome
printer are disclosed. For example, the method includes setting a
first scalar value of a channel of the monochrome printer, setting
a second scalar value of the channel of the monochrome printer,
generating a first layer of the multi-layer correlation mark at the
first scalar value of the channel, generating a second layer of the
multi-layer correlation mark at the second scalar value of the
channel and printing the multi-layer correlation mark comprising
the first layer at the first scalar value of the channel and the
second layer at the second scalar value of the channel.
Inventors: |
CHAPMAN; Edward; (Rochester,
NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Xerox Corporation |
Norwalk |
CT |
US |
|
|
Family ID: |
60157621 |
Appl. No.: |
15/142941 |
Filed: |
April 29, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04N 1/32251 20130101;
H04N 1/00838 20130101; H04N 1/32208 20130101; H04N 1/32219
20130101; H04N 2201/0094 20130101 |
International
Class: |
H04N 1/32 20060101
H04N001/32; H04N 1/32 20060101 H04N001/32; H04N 1/32 20060101
H04N001/32 |
Claims
1. A method for generating a multi-layer correlation mark via a
monochrome printer, comprising: setting, by a processor, a first
scalar value of a channel of the monochrome printer; setting, by
the processor, a second scalar value of the channel of the
monochrome printer, wherein the first scalar value and the second
scalar value each comprises a percentage value between 0 percent
and 100 percent of a level of modulation of the channel, wherein
the second scalar value and the first scalar value have a
difference greater than 25 percent; generating, by the processor, a
first layer of the multi-layer correlation mark at the first scalar
value of the channel; generating, by the processor, a second layer
of the multi-layer correlation mark at the second scalar value of
the channel; and printing, by the processor, the multi-layer
correlation mark comprising the first layer at the first scalar
value of the channel and the second layer at the second scalar
value of the channel.
2. The method of claim 1, wherein the channel of the monochrome
printer comprises a grayscale channel.
3. (canceled)
4. The method of claim 1, wherein the first scalar value is greater
than 10 percent.
5. (canceled)
6. The method of claim 1, wherein the first layer and the second
layer are offset by a predefined angle.
7. The method of claim 1, wherein the first layer and the second
layer each have a predefined frequency.
8. The method of claim 1, wherein the first layer displays a first
image when a key is applied to the multi-layer correlation
mark.
9. The method of claim 8, wherein the second layer displays a
second image within an area that that the first image was displayed
when the key is rotated by a predefined angle and is applied to the
multi-layer correlation mark, wherein the second image is different
from the first image.
10. A non-transitory computer-readable medium storing a plurality
of instructions, which when executed by a processor, cause the
processor to perform operations for generating a multi-layer
correlation mark via a monochrome printer, the operations
comprising: setting a first scalar value of a channel of the
monochrome printer; setting a second scalar value of the channel of
the monochrome printer, wherein the first scalar value and the
second scalar value each comprises a percentage value between 0
percent and 100 percent of a level of modulation of the channel,
wherein the second scalar value and the first scalar value have a
difference greater than 25 percent; generating a first layer of the
multi-layer correlation mark at the first scalar value of the
channel; generating a second layer of the multi-layer correlation
mark at the second scalar value of the channel; and printing the
multi-layer correlation mark comprising the first layer at the
first scalar value of the channel and the second layer at the
second scalar value of the channel.
11. The non-transitory computer-readable medium of claim 10,
wherein the channel of the monochrome printer comprises a grayscale
channel.
12. (canceled)
13. The non-transitory computer-readable medium of claim 10,
wherein the first scalar value is greater than 10 percent.
14. (canceled)
15. The non-transitory computer-readable medium of claim 10,
wherein the first layer and the second layer are offset by a
predefined angle.
16. The non-transitory computer-readable medium of claim 10,
wherein the first layer and the second layer are offset by a
predefined frequency.
17. The non-transitory computer-readable medium of claim 10,
wherein the first layer displays a first image when a key is
applied to the multi-layer correlation mark.
18. The non-transitory computer-readable medium of claim 17,
wherein the second layer displays a second image within an area
that the first image was displayed when the key is rotated by a
predefined angle and is applied to the multi-layer correlation
mark, wherein the second image is different from the first
image.
19. A method for generating a multi-layer correlation mark via a
monochrome printer, comprising: setting, by a processor, a first
scalar value, wherein the first scalar value represents a
percentage of a grayscale value of a grayscale channel of the
monochrome printer that is applied; setting, by the processor, a
second scalar value, wherein the second scalar value represents a
percentage of the grayscale value of the grayscale channel of the
monochrome printer that is applied, wherein the difference between
the second scalar value and the first scalar value is at least 25
percent; generating, by the processor, a first layer of the
multi-layer correlation mark via the grayscale value multiplied by
the first scalar value; generating, by the processor, a second
layer of the multi-layer correlation mark via the grayscale value
multiplied by the second scalar value; and printing, by the
processor, the multi-layer correlation mark comprising the first
layer and the second layer within a common area such that a first
image of the first layer and a second image of the second layer are
displayed within the common area via a key.
20. The method of claim 19, wherein the first layer and the second
layer are offset by a predefined angle.
Description
[0001] The present disclosure relates generally to security
printing and, more particularly, to a method and apparatus for
generating a multi-layer correlation mark via a monochrome
printer.
BACKGROUND
[0002] Many documents are protected for various different reasons
using various different methods. For example, documents can be
protected from copying, forging and counterfeiting using different
methods including security printing.
[0003] Some security printing requires specialty hardware and/or
materials. For example, a specialty document can be used for
prescriptions where a pharmacist would like to be able to have a
good level of confidence that the document is genuine.
SUMMARY
[0004] According to aspects illustrated herein, there are provided
a method, non-transitory computer readable medium and apparatus for
generating a multi-layer correlation mark via a monochrome printer.
One disclosed feature of the embodiments is a method that sets a
first scalar value of a channel of the monochrome printer, sets a
second scalar value of the channel of the monochrome printer,
generates a first layer of the multi-layer correlation mark at the
first scalar value of the channel, generates a second layer of the
multi-layer correlation mark at the second scalar value of the
channel and prints the multi-layer correlation mark comprising the
first layer at the first scalar value of the channel and the second
layer at the second scalar value of the channel.
[0005] Another disclosed feature of the embodiments is a
non-transitory computer-readable medium having stored thereon a
plurality of instructions, the plurality of instructions including
instructions which, when executed by a processor, cause the
processor to perform operations that set a first scalar value of a
channel of the monochrome printer, set a second scalar value of the
channel of the monochrome printer, generate a first layer of the
multi-layer correlation mark at the first scalar value of the
channel, generate a second layer of the multi-layer correlation
mark at the second scalar value of the channel and print the
multi-layer correlation mark comprising the first layer at the
first scalar value of the channel and the second layer at the
second scalar value of the channel.
[0006] Another disclosed feature of the embodiments is an apparatus
comprising a processor and a computer-readable medium storing a
plurality of instructions which, when executed by the processor,
cause the processor to perform operations that set a first scalar
value of a channel of the monochrome printer, set a second scalar
value of the channel of the monochrome printer, generate a first
layer of the multi-layer correlation mark at the first scalar value
of the channel, generate a second layer of the multi-layer
correlation mark at the second scalar value of the channel and
print the multi-layer correlation mark comprising the first layer
at the first scalar value of the channel and the second layer at
the second scalar value of the channel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The teaching of the present disclosure can be readily
understood by considering the following detailed description in
conjunction with the accompanying drawings, in which:
[0008] FIG. 1 illustrates an example apparatus of the present
disclosure;
[0009] FIG. 2 illustrates an example multi-layer correlation mark
of the present disclosure;
[0010] FIG. 3 illustrates examples of the multi-layer correlation
mark with the key overlaid on top;
[0011] FIG. 4 illustrates a flowchart of an example method for
generating a multi-layer correlation mark via a monochrome printer;
and
[0012] FIG. 5 illustrates a high-level block diagram of a computer
suitable for use in performing the functions described herein.
[0013] To facilitate understanding, identical reference numerals
have been used, where possible, to designate identical elements
that are common to the figures.
DETAILED DESCRIPTION
[0014] The present disclosure broadly discloses a method and
apparatus for generating a multi-layer correlation mark via a
monochrome printer. As discussed above, documents may be protected
for various different reasons using various different methods. For
example, documents can be protected from copying, forging and
counterfeiting using different methods including security
printing.
[0015] Some security printing requires specialty hardware and/or
materials. For example, a specialty document can be used for
prescriptions where a pharmacist would like to be able to have a
good level of confidence that the document is genuine.
[0016] However, one type of security printing that uses standard
materials such as standard paper, ink and toners is specialty
imaging from Xerox.RTM.. Currently, the specialty imaging creates a
multi-layer correlation mark using different colors on a multiple
color channel printer. However, monochrome printers only have a
single channel. As a result, monochrome printers cannot employ the
specialty imaging methods deployed by multiple color channel
printers.
[0017] Embodiments of the present disclosure provide a novel method
and apparatus generates a multi-layer correlation mark using a
monochrome printer by employing different scalar values of the
grayscale in each layer of the multi-layer correlation mark. Each
layer may be printed at a different angle and/or frequency using a
respective scalar value of the grayscale. The combined layers
printed by the monochrome printer may form the multi-layer
correlation mark for security printing applications.
[0018] FIG. 1 illustrates an example apparatus 100 of the present
disclosure. In one embodiment, the apparatus 100 may be a
multi-function device (MFD) that has print/scan/fax/copy
capabilities, an ink jet printer, a laser printer, and the
like.
[0019] In one embodiment, the apparatus 100 may have a single
channel. In other words, the apparatus 100 may only be capable of
printing in a single color.
[0020] In one embodiment, the apparatus 100 may be a monochrome
printer having a single channel that is grayscale. In other words,
the apparatus 100 may print in varying degrees of black and white
using a single grayscale channel.
[0021] In one embodiment, the apparatus 100 may include a processor
102, a multi-layer correlation mark generator 104 and a paper path
106. In one embodiment, the multi-layer correlation mark generator
104 may include instructions stored in a non-transitory computer
readable storage medium that are executed by the processor 102 to
perform the functions described herein to generate a multi-layer
correlation mark 110 on a printing medium 108 (e.g., paper).
[0022] In one embodiment, the processor 102 may receive an input to
generate the multi-layer correlation mark 110 over an Internet
protocol (IP) communication network via a wired or wireless
connection (not shown). The processor 102 may generate the
multi-layer correlation mark 110 using the multi-layer correlation
mark generator 104. The multi-layer correlation mark 110 may then
be printed onto the printing medium 108 via the paper path 106
under the control of the processor 102. In one embodiment, the
paper path 106 may include various hardware devices and modules
(e.g., rollers, paper nips, imaging devices, print heads, and the
like) used to transport the printing medium 108 and print the
multi-layer correlation mark 110.
[0023] FIG. 2 illustrates one example of the multi-layer
correlation mark 110. In one embodiment, the multi-layer
correlation mark 110 may comprise a combination of a first layer
202 and a second layer 204. In one embodiment, the first layer 202
may have a predefined frequency of lines 206 illustrated by a
periodic spacing 208 between the lines 206 illustrated in a box 212
that is a more detailed view of the first layer 202. In one
embodiment, the frequency may be defined as an inverse of the
periodic spacing 208 between the lines 206. In one embodiment, the
periodic spacing 208 may be measured from a middle of one line 206
to a middle of an adjacent line 206. In one embodiment, the
frequency may be 75 lines per inch, but could range from 35 to 150
lines per inch for a 600 dots per inch (dpi) resolution. In one
embodiment, the first layer 202 may have the lines 206 set at a
first angle .theta..sub.1.
[0024] In one embodiment, the lines 206 in the first layer 202 may
be printed by applying a first scalar value to the single channel
of the apparatus 100. For example, wherein the single channel is a
grayscale channel, the first scalar value may be a percentage value
between 0 percent and 100 percent of a level of modulation of the
single channel. In other words, the first scalar value may be a
percentage value of the black pixel (e.g., 100 percent, or the
pixel is "on") that is printed by the grayscale channel.
[0025] In one embodiment, the first scalar value may be greater
than 10 percent and up to 100 percent (e.g., 10%-100%). For
example, if the first scalar value is less than 10 percent the
lines 206 of the first layer 202 may not be visible enough to hide
and display an image contained in the first layer 202, as discussed
below.
[0026] In one embodiment, the second layer 204 may have a
predefined frequency of lines 207 as illustrated by a periodic
spacing 210 between the lines 207 illustrated in a box 214 that
shows a more detailed view of the second layer 204. In one
embodiment, the predefined frequency of the lines 207 may be the
same as the predefined frequency of lines 206 of the first layer
202. When the predefined frequency is the same for the lines 206
and 207, a single key can be used to decode the first layer 202 and
the second layer 204. In one embodiment, the periodic spacing 208
may be measured from a middle of one line 207 to a middle of an
adjacent line 207.
[0027] In one embodiment, the second layer 204 may have the lines
207 set at a second angle .theta..sub.2. In one embodiment, the
first angle and the second angle may be different or offset by a
predefined angle. In one embodiment, the difference between the
first angle and the second angle may be sufficient to allow the
first image in the first layer 202 and the second image in the
second layer 204 to be differentiated by a key, as described below.
In one embodiment, the second angle .theta..sub.2 may be
approximately 45 degrees, but less than approximately 135 degrees,
apart from the first angle .theta..sub.1.
[0028] In one embodiment, the lines 207 in the second layer 204 may
be printed by applying a second scalar value to the single channel
of the apparatus 100. For example, wherein the single channel is a
grayscale channel, the second scalar value may be a percentage
value between 0 percent and 100 percent of a level of modulation of
the single channel. In other words, the second scalar value may be
a percentage value of the black pixel (e.g., 100 percent, or the
pixel is "on") that is printed by the grayscale channel.
[0029] In one embodiment, the second scalar value may be at least
25 percent apart from the first scalar value. In other words, the
difference of the first scalar value and the second scalar value
should be at least 25 percent. For example, if the first scalar
value is 50 percent, then the second scalar value may be 25 percent
or 75 percent. In another example, if the first scalar value is 70
percent, then the second scalar value may be 45 percent or 90
percent, and so forth.
[0030] The first layer 202 and the second layer 204 may be combined
to generate the multi-layer correlation mark 110 and printed by the
apparatus 100 using a single channel (e.g., a monochrome printer
using a single grayscale channel). In one embodiment, the
multi-layer correlation mark 110 may be printed on a portion of the
printing medium 108.
[0031] FIG. 3 illustrates an example of the multi-layer correlation
mark 110 with a key 310 that is overlaid on top of the multi-layer
correlation mark 110. In a first example 302, the key 310 may have
a pattern that blocks the lines 207 of the second layer 204 to
allow a first image 306 to be visible from the first layer 202. For
example, the key 310 may have a pattern that has the same frequency
of lines 207 and at the same second angle .theta..sub.2. As a
result, when the key 310 is laid on top of the multi-layer
correlation mark 110, the first image 306 (e.g., illustrated as the
number "11") may be visible.
[0032] In a second example 304, the key 310 may be rotated by an
amount that is equal to the angular offset between the lines 206
and 207. In other words, the key 310 may have a second pattern that
is the same frequency as the lines 206 and at the same first angle
.theta..sub.1. As a result, when the key 310 is rotated by the
appropriate amount and laid on top of the multi-layer correlation
mark 110, a second image 308 (e.g., illustrated as the number "22")
may be visible.
[0033] Notably, the second image 308 may appear within the same
area that the first image 306 appeared. In other words, the first
layer 202 and the second layer 204 are printed such that the first
image 306 and the second image 308 occupy the same space or are
within a common area.
[0034] As a result, the present disclosure allows for security
printing using a monochrome printer that can only print in a single
color channel (e.g., grayscale). The present disclosure applies two
different scalar values to the grayscale channel to generate the
first layer 202 and the second layer 204. The first layer 202 and
the second layer 204 may then be offset or rotated by a predefined
angle and combined to print the multi-layer correlation mark
110.
[0035] FIG. 4 illustrates a flowchart of a method 400 for
generating a multi-layer correlation mark via a monochrome printer.
In one embodiment, one or more steps or operations of the method
400 may be performed by the apparatus 100 or a computer as
illustrated in FIG. 5 and discussed below.
[0036] At block 402, the method 400 begins. At block 404, the
method 400 sets a first scalar value of a channel of a monochrome
printer. In one embodiment, the channel of the monochrome printer
may be a single channel such as a grayscale channel.
[0037] In one embodiment, the first scalar value may be a
percentage value between 0 percent and 100 percent of a level of
modulation of the grayscale channel. In other words, the first
scalar value may be a percentage value of the black pixel (e.g.,
100 percent, or the pixel is "on") that is printed by the grayscale
channel.
[0038] In one embodiment, the first scalar value may be greater
than 10 percent and up to 100 percent (e.g., 10%-100%). For
example, if the first scalar value is less than 10 percent the
lines of a first layer may not be visible enough to hide and
display an image contained in the first layer, as discussed
below.
[0039] At block 406, the method 400 sets a second scalar value of
the channel of the monochrome printer. In one embodiment, the
second scalar value may be a percentage value between 0 percent and
100 percent of a level of modulation of the grayscale channel. In
other words, the second scalar value may be a percentage value of
the black pixel (e.g., 100 percent, or the pixel is "on") that is
printed by the grayscale channel.
[0040] In one embodiment, the second scalar value may be at least
25 percent apart from the first scalar value. In other words, the
difference of the first scalar value and the second scalar value
should be at least 25 percent. For example, if the first scalar
value is 50 percent, then the second scalar value may be 25 percent
or 75 percent. In another example, if the first scalar value is 70
percent, then the second scalar value may be 45 percent or 90
percent, and so forth.
[0041] At block 408, the method 400 generates a first layer of a
multi-layer correlation mark at the first scalar value of the
channel. For example, the first layer of the multi-layer
correlation mark may include an image that is formed by lines
having a predefined frequency and set at a first angle. The lines
of the first layer may be printed using an amount of the grayscale
channel multiplied by the first scalar value.
[0042] At block 410, the method 400 generates a second layer of the
multi-layer correlation mark at the second scalar value of the
channel. For example, the second layer of the multi-layer
correlation mark may include an image that is formed by lines
having the predefined frequency and set at a second angle. The
image of the second layer may be different than the image of the
first layer. The lines of the second layer may be printed using an
amount of the grayscale channel multiplied by the second scalar
value.
[0043] In one embodiment, the first angle and the second angle may
be offset by a predefined angle. The offset of the predefined angle
may determine the first angle and the second angle. For example, if
the offset is 90 degrees, the first angle may be 45 degrees and the
second angle may be 135 degrees, or the first angle may be 60
degrees and the second angle may be 150 degrees, and so forth. The
angles may be measured relative to a direction at the 12 o'clock
position of a circle being 0 degrees.
[0044] At block 412, the method 400 prints the multi-layer
correlation mark comprising the first layer at the first scalar
value of the channel and the second layer at the second scalar
value of the channel. For example, the multi-layer correlation mark
may be printed on a printing medium, such as paper to provide
printing security for the document.
[0045] In one embodiment, the multi-layer correlation mark may
display two different images within the same area when using a key.
For example, the key may have two different patterns. A first
pattern may be the inverse of the frequency of lines of the second
layer and at the same second angle of the lines of the second
layer. In other words, the first pattern may have a line where a no
line is printed in the first layer and no line where a line is
printed in the first layer. As a result, when the key is overlaid
on top of the multi-layer correlation mark, the second layer may be
"blocked" and allow the image of the first layer to appear.
[0046] Conversely, a second pattern of the key may be the inverse
of the frequency of lines of the first layer and at the same second
angle of the lines of the first layer. As a result, when the key is
rotated by the predetermined angle that first layer and the second
layer are offset by, the key may "block" the first layer and allow
the image of the second layer to appear within a common area.
[0047] Thus, the method 400 allows a monochrome printer that only
prints in black and white using a single grayscale channel to print
a multi-layer correlation mark. At block 414, the method 400
ends.
[0048] It should be noted that although not explicitly specified,
one or more steps, functions, or operations of the method 400
described above may include a storing, displaying and/or outputting
step as required for a particular application. In other words, any
data, records, fields, and/or intermediate results discussed in the
methods can be stored, displayed, and/or outputted to another
device as required for a particular application.
[0049] FIG. 5 depicts a high-level block diagram of a computer that
can be transformed to into a machine that is dedicated to perform
the functions described herein. As a result, the embodiments of the
present disclosure improve the operation and functioning of a
multi-function device to generate a multi-layer correlation mark
via a monochrome printer, as disclosed herein.
[0050] As depicted in FIG. 5, the computer 500 comprises one or
more hardware processor elements 502 (e.g., a central processing
unit (CPU), a microprocessor, or a multi-core processor), a memory
504, e.g., random access memory (RAM) and/or read only memory
(ROM), a module 505 for generating a multi-layer correlation mark
via a monochrome printer, and various input/output devices 506
(e.g., storage devices, including but not limited to, a tape drive,
a floppy drive, a hard disk drive or a compact disk drive, a
receiver, a transmitter, a speaker, a display, a speech
synthesizer, an output port, an input port and a user input device
(such as a keyboard, a keypad, a mouse, a microphone and the
like)). Although only one processor element is shown, it should be
noted that the computer may employ a plurality of processor
elements. Furthermore, although only one computer is shown in the
figure, if the method(s) as discussed above is implemented in a
distributed or parallel manner for a particular illustrative
example, i.e., the steps of the above method(s) or the entire
method(s) are implemented across multiple or parallel computers,
then the computer of this figure is intended to represent each of
those multiple computers. Furthermore, one or more hardware
processors can be utilized in supporting a virtualized or shared
computing environment. The virtualized computing environment may
support one or more virtual machines representing computers,
servers, or other computing devices. In such virtualized virtual
machines, hardware components such as hardware processors and
computer-readable storage devices may be virtualized or logically
represented.
[0051] It should be noted that the present disclosure can be
implemented in software and/or in a combination of software and
hardware, e.g., using application specific integrated circuits
(ASIC), a programmable logic array (PLA), including a
field-programmable gate array (FPGA), or a state machine deployed
on a hardware device, a computer or any other hardware equivalents,
e.g., computer readable instructions pertaining to the method(s)
discussed above can be used to configure a hardware processor to
perform the steps, functions and/or operations of the above
disclosed methods. In one embodiment, instructions and data for the
present module or process 505 for generating a multi-layer
correlation mark via a monochrome printer (e.g., a software program
comprising computer-executable instructions) can be loaded into
memory 504 and executed by hardware processor element 502 to
implement the steps, functions or operations as discussed above in
connection with the example method 400. Furthermore, when a
hardware processor executes instructions to perform "operations,"
this could include the hardware processor performing the operations
directly and/or facilitating, directing, or cooperating with
another hardware device or component (e.g., a co-processor and the
like) to perform the operations.
[0052] The processor executing the computer readable or software
instructions relating to the above described method(s) can be
perceived as a programmed processor or a specialized processor. As
such, the present module 505 for generating a multi-layer
correlation mark via a monochrome printer (including associated
data structures) of the present disclosure can be stored on a
tangible or physical (broadly non-transitory) computer-readable
storage device or medium, e.g., volatile memory, non-volatile
memory, ROM memory, RAM memory, magnetic or optical drive, device
or diskette and the like. More specifically, the computer-readable
storage device may comprise any physical devices that provide the
ability to store information such as data and/or instructions to be
accessed by a processor or a computing device such as a computer or
an application server.
[0053] It will be appreciated that variants of the above-disclosed
and other features and functions, or alternatives thereof, may be
combined into many other different systems or applications. Various
presently unforeseen or unanticipated alternatives, modifications,
variations, or improvements therein may be subsequently made by
those skilled in the art which are also intended to be encompassed
by the following claims.
* * * * *