Cross-platform hybrid printing method and system based on PDF virtual printer

Abstract

The invention belongs to the technical field of computer printing, and provides a cross-platform hybrid printing method and system based on a PDF virtual printer, and the method comprises the steps: creating a target PDF virtual printer in a printing client; the printing client obtains a printing task of a user and an initial printing file, and selects a target PDF virtual printer corresponding to a target client; the printing client generates a printing file from the initial printing file according to the printing task, the format of the printing file is converted through the target PDF virtual machine, and a PDF printing intermediate file is obtained and sent to the target client; the target client receives the PDF printing intermediate file and performs printing examination and approval, and if the examination and approval are passed, the PDF printing intermediate file is processed and sent to a physical printer for printing output; otherwise, printing is terminated. According to the invention, through standardization of the PDF format, the problem of driving compatibility among different operating systems is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of computer printing, and in particular relates to a cross-platform hybrid printing method and system based on a PDF virtual printer. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] In today's multi-platform, multi-device computing environment, users often need to perform printing tasks between different operating system platforms (such as Windows and Linux). However, the printing mechanisms and drivers between different operating systems are usually incompatible, which makes cross-platform printing complicated and inconvenient. Currently, the market lacks a simple, unified solution to meet cross-platform printing needs. Existing solutions usually rely on complex network configuration and driver installation, which not only increases the complexity of system maintenance, but also may cause performance bottlenecks and compatibility issues.

[0004] With the continuous advancement of enterprise information management, more and more enterprises are adopting IT environments with multiple operating systems. In this environment, users may need to create documents on a Windows system but print them using a Linux system, or vice versa. In addition, the rise of remote offices and distributed teams has also increased the demand for cross-platform printing. Therefore, there is an urgent need for a technology that can simplify cross-platform printing operations and improve user experience and work efficiency.

[0005] That is to say, existing solutions usually require complex driver configuration, especially in a cross-platform environment, which increases the complexity of system maintenance. Moreover, many existing solutions rely on specific network configurations and protocols, which increases the difficulty of deployment and usage threshold, and requires high network configuration. Then there are compatibility issues. Print drivers and protocols between different operating systems are incompatible, which may result in print tasks not being transmitted and printed correctly; and they are more dependent on cloud services, such as Google Cloud Print, which relies on cloud services for the transmission and management of print tasks. When the service stops or the network environment is poor, the printing function will be affected. Summary of the invention

[0006] In order to solve the above problems, the present invention proposes a cross-platform hybrid printing method and system based on a PDF virtual printer. The present invention realizes seamless printing task transmission and printing between Windows and Linux through a PDF virtual printer and a network transmission mechanism.

[0007] According to some embodiments, a first solution of the present invention provides a cross-platform hybrid printing method based on a PDF virtual printer, which adopts the following technical solution:

[0008] A cross-platform hybrid printing method based on a PDF virtual printer includes:

[0009] Create a target PDF virtual printer in the print client;

[0010] The printing client obtains the user's printing task and the initial printing file, and selects a target PDF virtual printer corresponding to the target client;

[0011] The printing client generates a printing file from the initial printing file according to the printing task, converts the printing file format using the target PDF virtual machine, obtains a PDF printing intermediate file and sends it to the target client;

[0012] The target client receives the PDF printing intermediate file and performs printing approval. If the approval is passed, the PDF printing intermediate file is processed and sent to a physical printer for print output; otherwise, printing is terminated.

[0013] Furthermore, the creating a target PDF virtual printer in the print client refers to creating target PDF virtual printers corresponding to a plurality of different target clients within a connectable range in the print client.

[0014] Furthermore, the printing client generates a printing file from the initial printing file according to the printing task, converts the printing file format using the target PDF virtual machine, obtains the PDF printing intermediate file and sends it to the target client, specifically:

[0015] When the print client is a Windows operating system, the initial print file is processed by the print background processing service to generate a print file in EMF / XPS format;

[0016] The target PDF virtual printer converts the EMS / XPS format print file into a PDF print intermediate file in PDF format;

[0017] When the print client is a Linux operating system, the target PDF virtual printer directly generates a PDF print intermediate file in PDF format from the initial print file after being processed by the general Unix print system.

[0018] Furthermore, the target PDF virtual printer converts the EMF / XPS format print file into a PDF print intermediate file in PDF format, specifically:

[0019] Initialize the PS / XPS interpreter;

[0020] Get the EMF / XPS format print file and parse it into internal graphic commands using the initialized PS / XPS interpreter;

[0021] The internal graphics commands are rendered using the rendering engine, converted into graphics state updates and commands, and then the graphics state updates and commands are combined with the internal graphics library for image preprocessing to generate internal images;

[0022] According to the internal image generated by the rendering engine, PDF objects, page numbers and resources are generated based on the PDF file infrastructure;

[0023] The internal image is stored in the object of the PDF file through the content stream, and the font embedding and subsetting operations are processed. After synthesis, the PDF printing intermediate file is obtained.

[0024] Furthermore, the target client receives the PDF printing intermediate file and performs printing approval. If the approval is passed, the PDF printing intermediate file is processed and sent to the physical printer for printing output, specifically:

[0025] The target client receives the PDF printing intermediate file and authenticates its user rights;

[0026] If the user authority authentication is successful, the approval is passed. When the target client is a Windows operating system, the PDF printing intermediate file is rendered to obtain a PDF rendering printing intermediate file;

[0027] The PDF rendering print intermediate file processed by the print background processing service is sent to the physical printer for print output.

[0028] Furthermore, the target client receives the PDF printing intermediate file and performs printing approval. If the approval is passed, the PDF printing intermediate file is processed and sent to the physical printer for printing output, specifically:

[0029] The target client receives the PDF printing intermediate file and authenticates its user rights;

[0030] If the user authority authentication is successful, the application is approved. When the target client is a Linux operating system, the PDF printing intermediate file is directly sent to the physical printer for print output.

[0031] Furthermore, the printing client sends the PDF printing intermediate file to the target client via the file transfer service.

[0032] Furthermore, the printing client obtains the user's printing task and the initial printing file, and selects the target PDF virtual printer corresponding to the target client, specifically:

[0033] Get the user's print task and initial print file;

[0034] Determine the target client based on the print task;

[0035] Then select the corresponding target PDF virtual printer according to the target client.

[0036] According to some embodiments, a second solution of the present invention provides a cross-platform hybrid printing system based on a PDF virtual printer, which adopts the following technical solution:

[0037] A cross-platform hybrid printing system based on PDF virtual printer, including printing client and target client;

[0038] The printing client is used to obtain the user's printing task and initial printing file, and select the target PDF virtual printer corresponding to the target client; generate a printing file from the initial printing file according to the printing task, convert the printing file format using the target PDF virtual machine, obtain a PDF printing intermediate file and send it to the target client;

[0039] The target client is used to receive the PDF printing intermediate file and perform printing approval. If the approval is passed, the PDF printing intermediate file is processed and sent to the physical printer for print output; otherwise, the printing is terminated.

[0040] Furthermore, the printing client is a client of a Linux operating system, or a client of a Windows operating system;

[0041] The target client is a client of a Linux operating system, or a client of a Windows operating system.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] The present invention supports cross-platform, and realizes seamless printing task transmission and printing between Windows and Linux through PDF virtual printer and network transmission mechanism. It is easy to deploy, and does not require complicated driver configuration. Users only need to install PDF virtual printer and simply configure network transmission service. It is highly flexible, supports multiple network transmission protocols, and adapts to different network environments. High compatibility: remote printing service can be compatible with multiple printer drivers to ensure smooth completion of printing tasks. Through the standardization of PDF format, driver compatibility issues between different operating systems are avoided, and the complexity of system maintenance and management is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0045] Figure 1 The present invention is a flowchart of a cross-platform hybrid printing method based on a PDF virtual printer in an embodiment of the present invention. DETAILED DESCRIPTION

[0046] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0047] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0048] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0049] In the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0050] Embodiment 1

[0051] This embodiment provides a cross-platform hybrid printing method based on a PDF virtual printer. In this embodiment, the method includes the following steps:

[0052] Create a target PDF virtual printer in the print client;

[0053] The printing client obtains the user's printing task and the initial printing file, and selects a target PDF virtual printer corresponding to the target client;

[0054] The printing client generates a printing file from the initial printing file according to the printing task, converts the printing file format using the target PDF virtual machine, obtains a PDF printing intermediate file and sends it to the target client;

[0055] The target client receives the PDF printing intermediate file and performs printing approval. If the approval is passed, the PDF printing intermediate file is processed and sent to a physical printer for print output; otherwise, printing is terminated.

[0056] Wherein, the creation of a target PDF virtual printer in the print client refers to creating a target PDF virtual printer corresponding to multiple different target clients within a connectable range in the print client. It is understandable that by integrating a user authority management function in the target client, an administrator can set printing authorities for different users to ensure the reasonable use and safe management of printing resources. In other words, the creation of multiple target PDF virtual printers described in this embodiment is created within the permitted range.

[0057] The printing client obtains the user's printing task and the initial printing file, and selects the target PDF virtual printer corresponding to the target client, specifically:

[0058] Get the user's print task and initial print file;

[0059] Determine the target client based on the print task;

[0060] Then select the corresponding target PDF virtual printer according to the target client.

[0061] The method generates a print file from an initial print file according to a print task based on a print client, converts the print file format using a target PDF virtual machine, obtains a PDF print intermediate file and sends it to a target client, specifically:

[0062] When the print client is a Windows operating system, the initial print file is processed by the print background processing service to generate a print file in EMF / XPS format;

[0063] The target PDF virtual printer converts the EMS / XPS format print file into a PDF print intermediate file in PDF format;

[0064] When the print client is a Linux operating system, the target PDF virtual printer directly generates a PDF print intermediate file in PDF format from the initial print file after being processed by the general Unix print system.

[0065] The target PDF virtual printer converts the EMF / XPS format print file into a PDF print intermediate file in PDF format, specifically:

[0066] Initialize the PS / XPS interpreter;

[0067] Get the EMF / XPS format print file and parse it into internal graphic commands using the initialized PS / XPS interpreter;

[0068] The internal graphics commands are rendered using the rendering engine, converted into graphics state updates and commands, and then the graphics state updates and commands are combined with the internal graphics library for image preprocessing to generate internal images;

[0069] According to the internal image generated by the rendering engine, PDF objects, page numbers and resources are generated based on the PDF file infrastructure;

[0070] The internal image is stored in the object of the PDF file through the content stream, and the font embedding and subsetting operations are processed. After synthesis, the PDF printing intermediate file is obtained.

[0071] The target client receives the PDF printing intermediate file and performs printing approval. If the approval is passed, the PDF printing intermediate file is processed and sent to the physical printer for printing output, specifically:

[0072] The target client receives the PDF printing intermediate file and authenticates its user rights;

[0073] If the user authority authentication is successful, the approval is passed. When the target client is a Windows operating system, the PDF printing intermediate file is rendered to obtain a PDF rendering printing intermediate file;

[0074] The PDF rendering print intermediate file processed by the print background processing service is sent to the physical printer for print output.

[0075] The target client receives the PDF printing intermediate file and performs printing approval. If the approval is passed, the PDF printing intermediate file is processed and sent to the physical printer for printing output, specifically:

[0076] The target client receives the PDF printing intermediate file and authenticates its user rights;

[0077] If the user authority authentication is successful, the application is approved. When the target client is a Linux operating system, the PDF printing intermediate file is directly sent to the physical printer for print output.

[0078] The printing client sends the PDF printing intermediate file to the target client via the file transfer service.

[0079] like Figure 1 As shown, the present invention relates to computer printing technology, which is a method for realizing cross-platform hybrid printing through a PDF virtual printer, and the process is as follows:

[0080] Step 0: Create a target PDF virtual printer (supports Windows and Linux operating systems). This refers to creating a target PDF virtual printer in the print client that initiates the print task.

[0081] Step 1: The user initiates a print task. The print client obtains, for example, a text document or an office document opened using a text document or WPS office software, initiates a print task, and selects the created target PDF virtual printer for output.

[0082] Step 2, print client and target PDF virtual printer processing. In the print client of Windows operating system, after being processed by spooler service, an EMF / XPS format print file will be generated. At this time, the target PDF virtual printer will convert the EMF / XPS format print file into PDF format; in the print client of Linux operating system, after being processed by cups service, the PDF virtual printer will directly generate a PDF print intermediate file in PDF format.

[0083] In the print client of Windows operating system, the monitor dynamic library portmonitor.dll of the target PDF virtual printer will be loaded by the spooler service. In the monitor dynamic library, several important core callback functions such as pfnEnumPorts (enumerate the available ports in the system), pfnOpenPort (open a specified port), pfnStartDocPort (notify the monitor that a document has started printing), pfnWritePort (write data to the port), pfnEndDocPort (notify the monitor that a document has finished printing), and pfnClosePort (close an open port) are all monitored. The core function of the virtual printer is implemented in the pfnWritePort callback function. In the pfnWritePort callback function, the monitor can obtain each page of data to be printed, and will convert it to the PS format / XPS format of EMF here. PS is a traditional data format, and each page of data can be converted to PDF data one by one. XPS is a new XML format, and the XPS format of XML is further extracted, parsed, and translated into PDF format here. After the entire printing action is completed, the intermediate PDF file is also generated.

[0084] The target PDF virtual printer will convert EMF / XPS format print files into PDF format. The detailed process is as follows:

[0085] 1) First, a PS / XPS interpreter will be initialized. The PS interpreter is used to interpret the PostScript language and interpret the PostScript language into internal graphic commands, that is, to parse the PS format data of EMF into internal graphic commands. The XPS interpreter is essentially an XML parser (XPS is based on the new XML format) that parses XPS data into internal graphic commands.

[0086] 2) Secondly, when the parser parses PS / XPS data, a series of runtime environments are provided to provide the parser with an operation stack, a dictionary stack, an operation status, an execution status, etc.

[0087] 3) Generate a rendering engine. After the parser parses the PS / XPS data into internal graphics commands, the rendering engine will accept these commands and convert them into graphics state updates and commands to describe the page content to be drawn.

[0088] 4) The rendering engine will combine the graphics state updates and commands with the internal graphics library to generate internal images based on different graphics functions (image scaling, rotation, conversion, etc.).

[0089] 5) The last step is the synthesis and output of PDF. A basic structure of a PDF file will be generated. According to the content generated by the rendering engine, PDF objects, number of pages, resources and other contents will be generated accordingly. The graphics and images generated by the renderer are stored in separate objects of the PDF file through the content stream. Finally, we will handle font embedding, subsetting and other operations to ensure that the PDF file can display the text correctly. After the PDF file is synthesized, the intermediate PDF file is also generated.

[0090] Step 3: After being processed by the target PDF virtual printer, the PDF printing intermediate file generated in step 2 is obtained.

[0091] Step 4: File transfer: The PDF printing intermediate file will be transferred to the target client system (Windows / Linux) via the file transfer service (FTP, http / https, minio, etc.).

[0092] Step 5: Target client approval. The PDF printing intermediate file arrives at the target client system (Windows / Linux). At this time, the administrator can approve the printing. If approved, other steps will be continued. If not, printing will be terminated directly.

[0093] Step 6: PDF file rendering. In the target client under Windows operating system, PDF printing intermediate files need to be rendered before they can be printed out by a physical printer. For the target client under Linux operating system, no task processing is required.

[0094] Step 7: The target client under the Windows operating system sends the rendered PDF printing intermediate file to the physical printer through the spooler service for printing output. The target client under the Linux operating system directly sends the PDF printing intermediate file to the physical printer through the cups service for printing output.

[0095] Specifically, this embodiment also records the print task log: a log recording function is integrated into the remote printing service to record detailed information of each print task (such as submission time, printer name, user ID, etc.) to facilitate auditing and troubleshooting.

[0096] This embodiment does not need to install a virtual printer on the server, but installs a virtual printer on the terminal; it does not rely on the RDP virtual data channel. At the terminal, you can obtain the data for page-by-page printing, and support converting PS / XPS data to PDF files page by page, and finally merge them into a complete PDF file. This technology does not retain the original PS / XPS data. This technology supports printing between Windows / Linux operating systems.

[0097] This embodiment does not require a script, and the conversion logic is executed by the dynamic library program inside the virtual printer.

[0098] Embodiment 2

[0099] This embodiment provides a cross-platform hybrid printing system based on a PDF virtual printer, including a printing client and a target client;

[0100] The printing client is used to obtain the user's printing task and initial printing file, and select the target PDF virtual printer corresponding to the target client; generate a printing file from the initial printing file according to the printing task, convert the printing file format using the target PDF virtual machine, obtain a PDF printing intermediate file and send it to the target client;

[0101] The target client is used to receive the PDF printing intermediate file and perform printing approval. If the approval is passed, the PDF printing intermediate file is processed and sent to the physical printer for print output; otherwise, the printing is terminated.

[0102] Furthermore, the printing client is a client of a Linux operating system, or a client of a Windows operating system;

[0103] The target client is a client of a Linux operating system, or a client of a Windows operating system.

[0104] The first client is a client of the Linux operating system or a client of the Windows operating system; the second client is a client of the Linux operating system or a client of the Windows operating system. That is to say, the printing process described in this embodiment can be PDF printing between Linux operating system and Linux operating system, PDF printing between Linux operating system and Windows operating system, PDF printing between Windows operating system and Windows operating system, or PDF printing between Windows operating system and Linux operating system.

[0105] The description of each embodiment in the above embodiments has different emphases. For parts not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0106] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A cross-platform hybrid printing method based on a PDF virtual printer, characterized in that: include: Create a target PDF virtual printer in the print client; The printing client obtains the user's printing task and the initial printing file, and selects a target PDF virtual printer corresponding to the target client; The printing client generates a printing file from the initial printing file according to the printing task, converts the printing file format using the target PDF virtual machine, obtains a PDF printing intermediate file and sends it to the target client; The target client receives the PDF printing intermediate file and performs printing approval. If the approval is passed, the PDF printing intermediate file is processed and sent to the physical printer for printing output; Otherwise, printing is terminated.

2. The cross-platform hybrid printing method based on PDF virtual printer according to claim 1, characterized in that: The creating a target PDF virtual printer in the print client refers to creating target PDF virtual printers corresponding to a plurality of different target clients within a connectable range in the print client.

3. The cross-platform hybrid printing method based on PDF virtual printer according to claim 1, characterized in that: The method generates a print file from an initial print file according to a print task based on a print client, converts the print file format using a target PDF virtual machine, obtains a PDF print intermediate file and sends it to a target client, specifically: When the print client is a Windows operating system, the initial print file is processed by the print background processing service to generate a print file in EMF / XPS format; The target PDF virtual printer converts the EMS / XPS format print file into a PDF print intermediate file in PDF format; When the print client is a Linux operating system, the target PDF virtual printer directly generates a PDF print intermediate file in PDF format from the initial print file after being processed by the general Unix print system.

4. The cross-platform hybrid printing method based on PDF virtual printer according to claim 3, characterized in that: The target PDF virtual printer converts the EMF / XPS format print file into a PDF print intermediate file in PDF format, specifically: Initialize the PS / XPS interpreter; Get the EMF / XPS format print file and parse it into internal graphic commands using the initialized PS / XPS interpreter; The internal graphics commands are rendered using the rendering engine, converted into graphics state updates and commands, and then the graphics state updates and commands are combined with the internal graphics library for image preprocessing to generate internal images; According to the internal image generated by the rendering engine, PDF objects, page numbers and resources are generated based on the PDF file infrastructure; The internal image is stored in the object of the PDF file through the content stream, and the font embedding and subsetting operations are processed. After synthesis, the PDF printing intermediate file is obtained.

5. The cross-platform hybrid printing method based on PDF virtual printer according to claim 1, characterized in that: The target client receives the PDF printing intermediate file and performs printing approval. If the approval is passed, the PDF printing intermediate file is processed and sent to the physical printer for printing output, specifically: The target client receives the PDF printing intermediate file and authenticates its user rights; If the user authority authentication is successful, the approval is passed. When the target client is a Windows operating system, the PDF printing intermediate file is rendered to obtain a PDF rendering printing intermediate file; The PDF rendering print intermediate file processed by the print background processing service is sent to the physical printer for print output.

6. The cross-platform hybrid printing method based on PDF virtual printer according to claim 1, characterized in that: The target client receives the PDF printing intermediate file and performs printing approval. If the approval is passed, the PDF printing intermediate file is processed and sent to the physical printer for printing output, specifically: The target client receives the PDF printing intermediate file and authenticates its user rights; If the user authority authentication is successful, the application is approved. When the target client is a Linux operating system, the PDF printing intermediate file is directly sent to the physical printer for print output.

7. The cross-platform hybrid printing method based on PDF virtual printer according to claim 1, characterized in that: The printing client sends the PDF printing intermediate file to the target client via the file transfer service.

8. The cross-platform hybrid printing method based on PDF virtual printer according to claim 1, characterized in that: The printing client obtains the user's printing task and the initial printing file, and selects the target PDF virtual printer corresponding to the target client, specifically: Get the user's print task and initial print file; Determine the target client based on the print task; Then select the corresponding target PDF virtual printer according to the target client.

9. A cross-platform hybrid printing system based on a PDF virtual printer, characterized in that: Including printing client and target client; The printing client is used to obtain the user's printing task and initial printing file, and select the target PDF virtual printer corresponding to the target client; Generate a print file from the initial print file according to the print task, convert the print file format using the target PDF virtual machine, obtain the PDF print intermediate file and send it to the target client; The target client is used to receive the PDF printing intermediate file and perform printing approval. If the approval is passed, the PDF printing intermediate file is processed and sent to the physical printer for printing output; Otherwise, printing is terminated.

10. The cross-platform hybrid printing system based on PDF virtual printer according to claim 9, characterized in that: The printing client is a client of a Linux operating system, or a client of a Windows operating system; The target client is a client of a Linux operating system, or a client of a Windows operating system.

Images