5) Blend in x*(reflecting/absorbing color1)+y*(reflecting/absorbing color2) . . .

The original inks used in step 1 can be designed using a color tool kit (e.g., such as the Xerox CTK) so pattern 1 and pattern 2 will appear as the same color/pattern at printed sizes under office lighting but only 1 pattern would allow the UV light to cause the paper to have a florescent property. A specific example of when the original inks fail is on, for example, the Xerox® Baltoro™ HF Inkjet Press where inks containing cyan that should not allow the paper to have a fluorescent property and there the watermark will not work.

For cyan, for example small amounts may be blended of yellow and magenta to keep that pattern from having a fluorescent property and maintaining the overall color of each pattern like the original. CTK can be used to optimize the pattern color matching. How strong a UV signal is considered passing is a judgement so swatch sheets varying the colors may be used.

The approach described above for configuring and rendering a fluorescent watermark, involves a systematic approach to modify existing pattern inks to achieve desired fluorescent effects while preserving the original color and pattern integrity under different lighting conditions. The process commences by utilizing existing pattern inks, as depicted in the example shown in FIG. 2, which exhibit varying degrees of reflectance and absorption across the electromagnetic spectrum. For each color that misses the reflection/absorption threshold in the UV spectrum, an assessment can be made to determine the amount of reflecting or absorbing colors that can be required to prevent fluorescence. Next, the amounts of individual reflecting or absorbing colors needed to maintain the original color and pattern under standard office lighting conditions can be determined. These reflecting or absorbing colors can be then blended in specific proportions, denoted by, for example, x*(reflecting/absorbing color1)+y*(reflecting/absorbing color2)+z*color 3, to achieve the desired fluorescent watermark effect while retaining the visual consistency of the original pattern.

In some embodiments, the original inks utilized in this process can be crafted using a Color ToolKit (CTK), such as the Xerox CTK (or another appropriate CTK), as discussed above, ensuring that pattern 1 and pattern 2 can appear almost identical (or similar) in color and pattern at printed sizes under office lighting. However, only one pattern may allow UV light to induce fluorescence, enhancing the security features of the document. For instance, in the case of cyan, small amounts of yellow and magenta may be blended to prevent the pattern from fluorescing while maintaining the overall color fidelity. The CTK can facilitate the optimization of pattern color matching, ensuring the effectiveness of the fluorescent watermark.

The determination of how strong a UV signal is considered acceptable is subjective and may involve the use of swatch sheets with varying color compositions to make informed judgments during the blending process. By following these systematic steps and leveraging advanced color management tools, manufacturers can effectively configure and render fluorescent watermarks that enhance document security while maintaining visual consistency and integrity.

As discussed previously in the background section of this disclosure, many/most modern papers fluoresce under UV illumination due to the chemical optical brighteners that have been added to make the papers appear “whiter”. We can thus take advantage of this for the disclosed UV effects. Thus, systems and methods are disclosed where there are “pattern ink pairs” wherein each “pattern ink” is a digital arrangement of colored pixels, which can result in differing amounts of standard C, M, Y, K inks/toners in a geometric pixel pattern, to be printed. For one “pattern ink” in the pair, the objective is to BLOCK the fluorescence of the paper (due to optical brighteners in the paper) under UV illumination; and for the other “pattern ink” in the pair, the objective is to ALLOW the paper fluorescence to show under UV illumination.

These steps or operations can be implemented such that under office lighting, the secret message does not show because the two pattern Inks are metameric pairs under that lighting (i.e., they appear to have the same color/density because the paper does not fluoresce under office lighting), but under UV illumination, the secret message shows or is visible because the two pattern inks are NOT metameric pairs under UV light (i.e., they appear to possess a different colors/density because the paper is fluorescing under UV light, and this paper fluorescence is selectively BLOCKED and ALLOWED by the “pattern inks” to create the secret message.

A problem the embodiments solve is the effect of native CMYK inks/toners of a system only partially blocking UV light, which weakens the UV blocking function of pattern ink designed for systems with better blocking CMYK ink/toners. The embodiments can help the user more quickly and easily combine CMYK inks/toners at specific densities IN A PATTERN INK pixel design, to deliver better blocking, thereby rendering the effect stronger.

It should be appreciated that the term “pattern ink” and variations thereof as utilized herein should not be confused with regular CMYK ink/toners. A “pattern ink” is not an ink. Instead, a “pattern ink” is an arrangement of pixels, with each pixel having a CMYK recipe (e.g., 0-100 or 0-255, depending on how it is counted) that in turn can drive a printing system to deliver that much (could be none) CMYK liquid ink or toner onto that pixel during printing. Furthermore, it is always the paper that is fluorescing in the disclosed improved specialty effects.

FIG. 3 illustrates an image 130 of zoomed pattern inks, in accordance with an embodiment. The image 130 depicts a close-up view of pattern inks, providing a detailed examination of their composition and arrangement. This zoomed-in depiction allows for a thorough analysis of the intricate patterns and colors employed in the printing process, providing insights into the complexity and precision that can be required to create effective security features.

FIG. 4 illustrates an image 140 of a swatch sheet under office lighting in which most patches are correctly non-readable, in accordance with an embodiment. In FIG. 4, most patches on the swatch sheet appear indistinguishable or non-readable to the naked eye. This visual uniformity underscores the subtlety of security measures incorporated into the printing process, ensuring that under normal lighting conditions, the presence of any security features remains discreet and inconspicuous. A central column 141 in FIG. 4 on the swatch sheet indicates various UV color types as one scans downward from top to bottom on the swatch sheet.

For example, the first color type is labeled as UV_BLAZE_ORANGE_301_A, and the next color type is labeled as UV_PINEBARK_302_A, and so on. Such labels can provide a unique identifier for each color variant present on the swatch sheet. For example, the designation of UV_BLAZE_ORANGE_301_A can relate to a specific shade or hue of orange that exhibits fluorescence under UV light. The term “blaze orange” typically denotes a bright and highly visible shade of orange used in safety apparel or signage. The “_301_A” suffix can indicate a specific variation or iteration of this color within a color classification system. Similarly, “UV_PINEBARK_302_A” can denote a particular shade or hue resembling the color of pine bark that fluoresces under UV light. Pine bark typically ranges in color from dark brown to reddish-brown, and this designation may represent a specific variant optimized for UV watermarking applications.

These example UV color types can be selected and calibrated to achieve optimal performance in security printing applications. By incorporating fluorescent properties into specific color variants, such as blaze orange and pine bark, these color types enable the creation of discreet yet effective security features. When applied to documents, these UV colors can remain inconspicuous under standard office lighting but become readily visible when exposed to UV illumination, thereby enhancing document security and authenticity. The use of distinct labels for each color type can facilitate precise color matching and reproduction during the printing process, ensuring consistency and accuracy across various printing systems and applications.

FIG. 5 illustrates an image 150 of the right side of the swatch sheet shown in FIG. 4 under UV lighting in which most patches are readable, in accordance with an embodiment. In FIG. 5, we can observe the right side of the same swatch sheet depicted in FIG. 4, but under UV lighting. Here, a striking contrast emerges as most patches on the swatch sheet become distinctly readable under the UV illumination. This transformation highlights the effectiveness of the fluorescent watermarking technique employed in the printing process, as it selectively reveals hidden patterns and features only under specific lighting conditions, thereby enhancing the document's security and authenticity.

Collectively, these images illustrate the intricate interplay between standard and UV lighting conditions, showcasing how sophisticated printing techniques can create visually imperceptible security features that become readily apparent when subjected to specialized illumination. This strategic integration of covert security measures ensures that documents remain protected against counterfeiting and unauthorized duplication, bolstering confidence in their authenticity and integrity.

FIG. 6 illustrates a high-level flow chart of operations depicting a method 160 for creating a fluorescent watermark, in accordance with an embodiment. As shown at block 161, a step or operation can be implemented by utilizing existing pattern inks, an example of which is depicted in FIG. 2, which can exhibit varying degrees of reflectance and absorption across the electromagnetic spectrum. This initial step can involve leveraging existing pattern inks, as exemplified by FIG. 2, which possess diverse reflectance and absorption characteristics across the electromagnetic spectrum. These inks can serve as the foundational elements upon which the fluorescent watermark can be constructed.

For colors that lack partial reflection or absorption in the UV spectrum, a series of operations are undertaken to optimize their properties for fluorescent watermark creation. As depicted next at block 162, a step or operation can be implemented wherein for each color that is not partially reflective/absorbing in the UV spectrum, the subsequent operations shown at blocks 163, 164, and 165 may be implemented. That is, as indicated at block 163, a step or operation can be implemented to determine amounts of reflecting/absorbing colors needed to prevent fluorescence. Then, as illustrated at block 164, a step or operation can be implemented to determine amounts of individual reflecting/absorbing colors needed to keep original color/pattern under office lighting. Finally, as shown at block 165, a step or operation can be implemented to blend in x*(reflecting/absorbing color1)+y*(reflecting/absorbing color2). The result of this is the creation of a fluorescent watermark, which can be rendered by a broad range of printing systems.

The step or operation shown at block 163 can involve determining the quantities of reflecting or absorbing colors necessary to prevent fluorescence, ensuring that the resultant watermark remains covert under standard lighting conditions. The step or operation indicated at block 164 can entail determining the precise amounts of individual reflecting or absorbing colors that may be required to preserve the original color and pattern integrity under typical office lighting. The step or operation illustrated at block 165 can involve a blending process, wherein the identified reflecting or absorbing colors can be combined in specific proportions (e.g., denoted by x*(reflecting/absorbing color1)+y*(reflecting/absorbing color2)). This meticulous blending technique can therefore ensure the creation of a fluorescent watermark that seamlessly integrates with the original design while enhancing document security.

FIG. 7 illustrates a block diagram of a printing system 200 suitable for implementing one or more of the disclosed embodiments. FIG. 8 illustrates a block diagram of a digital front-end controller 300 useful for implementing one or more of the disclosed embodiments. For example, the printing system 200 and/or the digital front-end controller 300 can be used to render a document with a yellow, black gloss effect.

With reference to FIG. 7, a printing system (or image rendering system) 200 suitable for implementing various aspects of the exemplary embodiments described herein is illustrated. The printing system 200 can implement rendering operations such as scanning a document via a scanner and printing a document via a printer, wherein the document can exhibit the disclosed fluorescent watermark.

Note that the term ‘scanner’ as utilized herein may refer to an image scanner, which is a device or system that can optically scan images, printed text, handwriting or an object and converts it to a digital image. An example of a scanner is a flatbed scanner where the document to be imaged (e.g., a form) can be placed on a glass window for scanning. The scanner may in some cases be incorporated into a multi-function device (MFD), which also may possess printing and photocopying features. The scanner may also be incorporated into, for example, a printing system such as the printing system 200 shown in FIG. 7. For example, the scanner 229 is shown in FIG. 7 as a part of the printing system 200. Alternatively, or in addition to the scanner 229 included as a part of the printing system 100, a scanner may be implemented as a separate scanner 262 also depicted in FIG. 7, which can communicate with the network 260.

The word “printer” and the term “printing system” as used herein can encompass any apparatus and/or system; such as a digital copier, xerographic and reprographic printing systems, bookmaking machine, facsimile machine, multi-function machine, ink-jet machine, continuous feed, sheet-fed printing device, etc.; which may contain a print controller and a print engine and which may perform a print outputting function for any purpose.

The printing system 200 can include a user interface 210, a digital front-end (DFE) controller 220, and at least one print engine 230. The print engine 230 has access to print media 235 of various sizes and cost for a print job. The printing system 200 can comprise a color printer having multiple color marking materials.

A “print job” or “document” is normally a set of related sheets, usually one or more collated copy sets copied from a set of original print job sheets or electronic document page images, from a particular user, or otherwise related. For submission of a regular print job (or customer job), digital data can be sent to the printing system 200.

A sorter 240 can operate after a job is printed by the print engine 230 to manage arrangement of the hard copy output, including cutting functions. A user can access and operate the printing system 200 using the user interface 210 or via a data-processing system such as a computer 250. The computer 250 can communicate bidirectionally with the printing system 200 via a communications network 260. As shown in FIG. 87 the computer 250 includes a screen (display screen) upon which a digital image may be displayed and viewed by a user.

A user profile, a work product for printing, a media library, and various print job parameters can be stored in a database or memory 270 accessible by the computer 250 or the printing system 200 via the network 260, or such data can be directly accessed via the printing system 200. One or more color sensors (not shown) may be embedded in the printer paper path, as known in the art.

With respect to FIG. 8, an exemplary DFE (Digital Front End) controller 300 is shown in greater detail. The DFE controller 300 can include one or more processors, such as processor 306, which is capable of executing machine executable program instructions. The processor 306 can function as a DFE processor.

In the embodiment shown in FIG. 8, the processor 306 can be in communication with a bus 302 (e.g., a backplane interface bus, cross-over bar, or data network). The digital front end 300 can also include a main memory 304 that is used to store machine readable instructions. The main memory 304 is also capable of storing data. The main memory 304 may alternatively include random access memory (RAM) to support reprogramming and flexible data storage. A buffer 366 can be used to temporarily store data for access by the processor 306.

Program memory 364 can include, for example, executable programs that can implement the embodiments described herein. The program memory 364 can store at least a subset of the data contained in the buffer. The digital front end 300 can include a display interface 308 that can forward data from a communication bus 302 (or from a frame buffer not shown) to a display 310. The digital front end 300 can also include a secondary memory 312 that can include, for example, a hard disk drive 314 and/or a removable storage drive 316, which can read and write to removable storage 318, such as a floppy disk, magnetic tape, optical disk, etc., that stores computer software and/or data.

The secondary memory 312 alternatively may include other similar mechanisms for allowing computer programs or other instructions to be loaded into the computer system. Such mechanisms can include, for example, a removable storage unit 322 adapted to exchange data through interface 320. Examples of such mechanisms include a program cartridge and cartridge interface (such as that found in video game devices), a removable memory chip (such as an EPROM, or PROM) and associated socket, and other removable units and interfaces, which allow software and data to be transferred.

The digital front end (DFE) controller 300 shown in FIG. 8 can include a communications interface 324, which can act as an input and an output to allow software and data to be transferred between the digital front end controller 300 and external devices. Examples of a communications interface include a modem, a network interface (such as an Ethernet card), a communications port, a PCMCIA slot and card, etc.

Computer programs (also called computer control logic) and including one or more modules may be stored in the main memory 304 and/or the secondary memory 312. Computer programs or modules may also be received via a communications interface 324. Such computer programs or modules, when executed, enable the computer system to perform the features and capabilities provided herein. Software and data transferred via the communications interface can be in the form of signals which may be, for example, electronic, electromagnetic, optical, or other signals capable of being received by a communications interface.

These signals can be provided to a communications interface via a communications path (i.e., channel), which carries signals and may be implemented using wire, cable, and fiber optic, phone line, cellular link, RF, or other communications channels. Part of the data stored in secondary memory 312 for access during a DFE operation may be a set of translation tables that can convert an incoming color signal into a physical machine signal.

This color signal can be expressed either as a colorimetric value; usually three components as L*a*b*, RGB, XYZ, etc.; into physical exposure signals for the four toners cyan, magenta, yellow and black. These tables can be created outside of the DFE and downloaded but may be optionally created inside the DFE in a so-called characterization step. Part of the data stored in secondary memory 312 may also be the previously discussed transformation table.

The fluorescent watermark created and rendered by the methods described earlier can be implemented in the printing system (or image rendering system) 200 depicted in FIG. 7 and managed by the digital front-end (DFE) controller 300 illustrated in FIG. 8. The printing system 200 and the DFE controller 300 can facilitate the rendering of documents with the fluorescent watermark. The printing system 200 includes components such as a user interface 210, a DFE controller 220, and at least one print engine 230. It also features a sorter 240 for organizing printed output and managing cutting functions.

The print engine 230 can be responsible for applying the fluorescent watermark onto the print media 235, which can include various types and sizes of paper for accommodating different print jobs. The user interface 210 can allow users to interact with the printing system 200, providing options for initiating print jobs, adjusting settings, and monitoring printing processes. The printing system 200 can support the creation and printing of documents with specialized effects, including the yellow, black gloss effect mentioned in the description.

The DFE controller 300 depicted in FIG. 8 can serve as the processing hub for managing print jobs and ensuring the accurate rendering of documents. The processor 306 is capable of executing machine-readable instructions stored in main memory 304 and program memory 364. The DFE controller 300 can communicate bidirectionally with external devices, such as computers 250, via a communications interface 324 and network 260, and can facilitate the transformation of digital data into printable output, orchestrating the conversion of color signals into physical machine signals for cyan, magenta, yellow, and black toners.

The DFE controller 300 shown in FIG. 8 can also utilize translation tables stored in secondary memory 312 to convert incoming color signals into appropriate toner exposure signals, ensuring accurate color reproduction and effective implementation of the fluorescent watermark. By integrating the fluorescent watermark creation process into the printing system's workflow and leveraging the capabilities of the DFE controller, documents can be rendered with the desired security features. The utilized printing system can effectively apply the fluorescent watermark onto print media, while the DFE controller orchestrates the conversion of digital data into printable output, ensuring fidelity to the original design and enhancing document security. This seamless integration can enable the printing system to produce documents with advanced security features, including the disclosed fluorescent watermark, across a variety of printing applications and media types.

Several aspects of data-processing systems will now be presented with reference to various systems and methods. These systems and methods will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, etc. (collectively referred to as “elements”). These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

By way of example, an element, or any portion of an element, or any combination of elements may be implemented with a “processing system” that includes one or more processors. Examples of processors include microprocessors, microcontrollers, digital signal processors (DSPs), field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionality described throughout this disclosure. One or more processors in the processing system may execute software. Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. A mobile “app” is an example of such software.

Accordingly, in one or more exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or encoded as one or more instructions or code on a computer-readable medium. Computer-readable media includes computer storage media. Storage media may be any available media that can be accessed by a computer.

The disclosed example embodiments are described at least in part herein with reference to flowchart illustrations and/or block diagrams and/or schematic diagrams of methods, systems, and computer program products and data structures according to embodiments of the invention. It will be understood that each block of the illustrations, and combinations of blocks, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of, for example, a general-purpose computer, special-purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the block or blocks.

To be clear, the disclosed embodiments can be implemented in the context of, for example a special-purpose computer or a general-purpose computer, or other programmable data processing apparatus or system. For example, in some example embodiments, a data processing apparatus or system can be implemented as a combination of a special-purpose computer and a general-purpose computer. The computer program product may include a computer readable storage medium (or media) having computer readable program instructions thereon for causing a processor to carry out aspects of the embodiments.

The aforementioned computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions (e.g., steps/operations) stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function/act specified in the various block or blocks, flowcharts, and other architecture illustrated and described herein.

The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions/acts specified in the block or blocks.

The flow charts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments (e.g., preferred or alternative embodiments). In this regard, each block in the flow chart or block diagrams depicted and described herein can represent a module, segment, or portion of instructions, which can comprise one or more executable instructions for implementing the specified logical function(s).

In some alternative implementations, the functions noted in the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems that perform the specified functions or acts or carry out combinations of special purpose hardware and computer instructions.

The functionalities described herein may be implemented entirely and non-abstractly as physical hardware, entirely as physical non-abstract software (including firmware, resident software, micro-code, etc.) or combining non-abstract software and hardware implementations that may be referred to herein as a “circuit,” “module,” “engine”, “component,” “block”, “database”, “agent” or “system.” Furthermore, aspects of the present disclosure may take the form of a computer program product embodied in one or more non-ephemeral computer readable media having computer readable and/or executable program code embodied thereon.

The following discussion is intended to provide a brief, general description of suitable computing environments in which the system and method may be implemented. Although not required, the disclosed embodiments will be described in the general context of computer-executable instructions, such as program modules, being executed by a single computer. In most instances, a “module” (also referred to as an “engine”) may constitute a software application but can also be implemented as both software and hardware (i.e., a combination of software and hardware).