A cloud service-based printing method and system for super large format files

Abstract

The application discloses a printing method and system of super large format files based on cloud services, and relates to the technical field of printing. The method comprises the following steps: a printer receives a printing message which is divided into multiple network messages, and obtains the size of a format file to be printed from the network messages. If the size of the format file exceeds a preset available memory safety value of the printer, printing work order information is obtained from the network messages, and the network messages are restructured and sent to a cloud server, and the available memory safety value of the printer is also sent to the cloud server. After the cloud server receives the network messages, the format file is separated. According to the available memory safety value of the printer, the format file is restructured into a plurality of segmentation files with sizes not exceeding the value. The printer continuously receives the segmentation files from the cloud server, and constructs a printing task for each segmentation file according to the printing work order. The application breaks through the limitation of the printer memory, realizes the printing of super large format files, and does not require the user to interact with the cloud server, thereby guaranteeing the user experience.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of printing technology, in particular to a printing method and system of super large format file based on cloud service. BACKGROUND

[0002] Traditional printers can only receive and print stream files such as PCL, PostScript, etc. Stream files are print description languages, which facilitate the printer to print part of the received print data, such as a page of content. In this case, the print application end needs to first convert the file into a stream file, and this part of the work is usually completed by the print driver. In recent years, in order to provide better printing experience for users, driverless printing has become the development direction of printing. One implementation scheme of driverless printing is that the printer supports direct printing of format files such as PDF and OFD, and the print application can output the file as a general format file such as PDF or OFD, and then directly send it to the printer.

[0003] However, the format file needs to be transmitted to the printer in its entirety, and the printer can only analyze the entire file to generate raster image information for each page after parsing. Due to the limited memory resources of the printer, super large format files that exceed the memory of the printer cannot be received and printed, and system crashes are prone to occur due to insufficient memory. SUMMARY

[0004] To solve the above-mentioned defects or deficiencies, the present application provides a printing method and system of super large format file based on cloud service, which breaks through the memory limit of the printer and realizes driverless printing of super large format files.

[0005] In one aspect of the present application, a printing method of super large format file based on cloud service is provided, comprising:

[0006] The printer receives the print message data sent by the print client, which is divided into multiple network messages, obtains the size of the format file to be printed from the network message according to the print protocol, and if the size of the format file exceeds the preset available memory safety value of the printer, the printer obtains the print work order information from the network message, and sends the network message after reconstruction to the cloud server, and sends the available memory safety value of the printer to the cloud server.

[0007] The cloud server receives the restructured network message and the safe value of the available memory of the printer, reorganizes all the network messages into print messages, separates the layout files from the print messages, and reorganizes the layout files into a plurality of split files according to the safe value of the available memory of the printer, wherein the size of the split files does not exceed the safe value of the available memory of the printer, the split files are renamed according to the page numbers, the split files are packaged and sent to the printer in the order of the page numbers, and the cloud server does not check the host attribute value of the HTTP package header in the network message when receiving the network message.

[0008] The printer receives the split files sent by the cloud server, and constructs a print task for each split file according to the print order information.

[0009] Further, the step of sending the restructured network message to the cloud server comprises:

[0010] modifying the source port of the TCP header of each network message to the local port of the printer, modifying the destination port to the service port of the cloud server, recalculating and updating the checksum of the TCP header;

[0011] modifying the source IP address of the IP header of each network message to the IP address of the printer, modifying the destination IP address to the IP address of the cloud server, recalculating and updating the checksum of the IP header;

[0012] sending the restructured network message to the cloud server, and deleting the network messages that have been processed and successfully sent.

[0013] Further, the step of reorganizing the layout files into a plurality of split files according to the safe value of the available memory of the printer comprises:

[0014] analyzing the file structure of the layout file, generating a folder framework of the split file according to the file structure, and the folder framework comprises a page folder, a resource folder and a document information description file;

[0015] extracting the contents of the layout file except the page folder, and copying and placing them into the folders of the split file except the page folder;

[0016] extracting the page contents of the layout file in the order of the page numbers, and copying and placing them into the page folder;

[0017] checking whether the size of the split file exceeds the safe value of the available memory of the printer, and if so, reducing the number of pages contained in the split file until the size of the split file does not exceed the safe value of the available memory of the printer;

[0018] According to the page content of the split file, a document information description file of the split file is modified.

[0019] Further, the method further comprises removing public resources irrelevant to the partial page content according to a public resource ID referenced by the partial page content.

[0020] Further, the public resources comprise fonts, graphics and images.

[0021] Optionally, the cloud server further comprises a font library stored in the cloud server, and the cloud server is configured to parse characters in the layout file by using the font library, and add font data of the fonts into the split file of the layout file.

[0022] In another aspect of the present application, a printing system for a super large layout file based on a cloud service is provided, comprising:

[0023] a printing client configured to send print message data split into a plurality of network messages to a printer;

[0024] a printer comprising a print service interface, an analysis module, a forwarding module and a print processing module; the print service interface is configured to receive the print message data split into a plurality of network messages sent by the printing client; the analysis module is configured to obtain the size of a layout file to be printed from the network messages according to a print protocol, and obtain print work order information from the network messages if the size of the layout file exceeds a preset printer available memory safety value; the forwarding module is configured to establish a connection with a cloud server, and send the network messages to the cloud server after reconstruction, and send the printer available memory safety value to the cloud server; and the print processing module is configured to receive split files sent by the cloud server, and construct a print task for each of the split files according to the print work order information.

[0025] a cloud server comprising a large file processing service interface and a layout file splitting tool; the large file processing service interface is configured to receive the reconstructed network messages and the printer available memory safety value sent by the printer, recombine all the network messages into a print message, separate the layout file from the print message, and not check the host attribute value of the HTTP packet header in the network message when receiving the network message; and the layout file splitting tool is configured to recombine the layout file into a plurality of split files according to the printer available memory safety value, the size of each of the split files does not exceed the printer available memory safety value, the split files are renamed according to page numbers, the split files are packaged and sent to the printer in sequence according to the page number order.

[0026] Further, the forwarding module is further configured to:

[0027] Modifying the source port of the TCP header of each network packet to the local port of the printer and the destination port to the service port of the cloud server, recalculating and updating the checksum of the TCP header;

[0028] Modifying the source IP address of the IP header of each network packet to the IP address of the printer and the destination IP address to the IP address of the cloud server, recalculating and updating the checksum of the IP header;

[0029] Sending the restructured network packet to the cloud server and deleting the network packet that has been processed and successfully sent.

[0030] Further, the layout file splitting tool is further used for:

[0031] Analyzing the file structure of the layout file, generating a folder framework of the split file according to the file structure, and the folder framework including a page folder, a resource folder and a document information description file;

[0032] Extracting the content of the layout file except the page folder, copying and placing the content into the folder outside the page folder of the split file;

[0033] Extracting part of the page content of the layout file in the order of page number, copying and placing the part of the page content into the page folder;

[0034] Checking whether the size of the split file exceeds the safe value of the available memory of the printer, and if yes, reducing the number of pages contained in the split file until the size of the split file does not exceed the safe value of the available memory of the printer;

[0035] Modifying the document information description file of the split file according to the page content of the split file.

[0036] Further, the layout file splitting tool is further used for: removing the public resource irrelevant to the part of the page content according to the public resource ID referred to by the part of the page content.

[0037] The application provides a printing method and system of a super large format file based on cloud service, which combines a printer and a cloud server to process the super large format file, judges the size of the format file through a network message, and enables the cloud server to assist in printing when the format file exceeds the safe value of the available memory of the printer, forwards the network message to the cloud server while receiving, avoids complete residence of the printing file in the memory of the printer, avoids the risk of memory overflow, breaks through the limitation of the memory of the printer, and realizes the printing of the super large format file; the cloud server reorganizes the super large format file into segmented files based on the structure of the format file, removes irrelevant resources according to the public resource ID referenced by the pages of the segmented files, realizes that the segmented files maintain the integrity of independent printing and the simplicity of resources to reduce the file size, and reconstructs the printing task into a sub-printing task of each segmented file according to the printing order information extracted from the network message, so that the printer receives and prints the segmented files in sequence, and the user perceives continuous operation without manual intervention. The printing method provided by the embodiment breaks through the limitation of the memory of the printer, realizes the printing of the super large format file, and does not require the user to interact with the cloud server, thereby guaranteeing the user experience. BRIEF DESCRIPTION OF DRAWINGS

[0038] Other characteristics, objects and advantages of the present application will become more apparent from the following detailed description of non-restrictive embodiments, made with reference to the attached drawings:

[0039] Figure 1 Fig. 1 is a flowchart of a printing method of a super large format file based on cloud service provided by an embodiment of the present application;

[0040] Figure 2 Fig. 2 is a structural diagram of a printing system of a super large format file based on cloud service provided by an embodiment of the present application. DETAILED DESCRIPTION

[0041] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0042] The terms used in the embodiments of the present application are merely for the purpose of describing the specific embodiments, and are not intended to limit the present application. The singular forms "a", "an" and "the" used in the embodiments of the present application are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0043] It should be understood that, although the terms first, second, third, etc. can be employed in describing the obtaining modules in the embodiments of the present application, the obtaining modules should not be limited to these terms. These terms are only used to distinguish the obtaining modules from each other.

[0044] Depending on context, the word "if" as used herein can be interpreted as meaning "when" or "while" or "in response to determining" or "in response to detecting." Similarly, depending on context, the phrase "if it is determined" or "if [a stated condition or event] is detected" can be interpreted to mean "when it is determined" or "in response to determining" or "when [a stated condition or event] is detected" or "in response to detecting [a stated condition or event]."

[0045] It should be noted that the terms "upper", "lower", "left", "right", etc. described in the embodiments of the present application are described in the angle shown in the drawings, and should not be understood as a limitation on the embodiments of the present application. In addition, in the context, it should also be understood that when referring to an element being formed "on" or "under" another element, it can not only be directly formed "on" or "under" another element, but also indirectly formed "on" or "under" another element through an intermediate element.

[0046] With reference to Figure 1 The present application provides a printing method of a large format file based on cloud service, comprising the following steps:

[0047] In step S101, the printer receives the print message data sent by the print client, which is divided into multiple network messages. The size of the format file to be printed is obtained from the network message according to the print protocol. If the size of the format file exceeds the preset safe value of the available memory of the printer, the printer obtains the print work order information from the network message, and sends the network message after reconstruction to the cloud server, and sends the safe value of the available memory of the printer to the cloud server.

[0048] Specifically, the print client generates a print message from a layout file to be printed, and when transmitting the print message over a network, the print message is divided and added with a TCP header and an IP header to form a plurality of network messages sent to the printer, wherein the print message includes an HTTP header, print job information, and a layout file, the network message includes an IP header, a TCP header, and a print message segment, the print message segment includes an HTTP header and a divided layout file, wherein the print job information is also included in the print message segment of the first network message, and in particular, when the HTTP header and the print job information in the print message are too large, the print job information will be divided into the second network message when the print message is divided into network messages. According to the print protocol, the size of the layout file to be printed is obtained from the network message, for example, using the IPP (Internet Printing Protocol) protocol, the size of the layout file to be printed is obtained from the print job information in the network message, and using the LPD (Line Printer Daemon) protocol, the size of the layout file to be printed is obtained from the HTTP header. The size of the layout file is compared with a preset safe value of available memory of the printer, for example, the preset safe value of available memory of the printer is 50% of the printer memory, if the size of the layout file does not exceed 50% of the printer memory, the printer directly prints after receiving the layout file in its entirety, if the size of the layout file exceeds 50% of the printer memory, the print job information is obtained from the network message to prepare for subsequent printing process based on cloud service, wherein the print job information includes metadata and control instructions about the print job, such as print quantity, page range, paper size, double-sided printing setting, and job name, for example, the printer obtains the print job information from the network message according to the IPP protocol: print pages 9-15, print 5 copies.

[0049] The printer establishes a connection with the cloud server, such as through a TCP socket program, and while continuously receiving network messages, the received network messages are reconstructed and sent to the cloud server, the specific steps include:

[0050] The source port of the TCP header of each network packet is modified to the local port of the printer, the destination port is modified to the service port of the cloud server, the TCP header checksum is recalculated and updated, for example, the print application port is 1111, the IP address is 111.111.111, the local port of the printer is 2222, the IP address is 222.222.222, the cloud server port is 3333, the IP address is 233.233.233, the source port of the TCP header of the data packet is modified from 1111 to 2222, the destination port is modified from 2222 to 3333, because the source port and the destination port of the TCP header are modified, the TCP checksum needs to be recalculated and updated;

[0051] The source IP address of the IP header of each network packet is modified to the IP address of the printer, the destination IP address is modified to the IP address of the cloud server, the IP header checksum is recalculated and updated, for example, the source IP address of the IP header of the network packet is modified from 111.111.111 to 222.222.222, the destination IP address is modified from 222.222.222 to 233.233.233, because the source port and the destination port of the IP header are modified, the IP checksum needs to be recalculated and updated;

[0052] The reconstructed network packet is sent to the cloud server, the network packet that has been processed and successfully sent is deleted, thereby each network packet is received and forwarded until all print message data of the print format file is sent to the cloud server, avoiding that the complete format file exceeding the available memory safety value of the printer resides in the printer memory, avoiding the risk of memory overflow, at the same time, the available memory safety value of the printer is also sent to the cloud server, after all data is sent, the TCP session is disconnected.

[0053] In step S102, after the cloud server receives the reconstructed network packet sent by the printer and the available memory safety value of the printer, all the network packets are recombined into print messages, the print format file is separated from the print messages, and the print format file is recombined into a plurality of split files according to the available memory safety value of the printer, the size of the split file does not exceed the available memory safety value of the printer, the split file is renamed according to the page number, the split file is packaged and sent to the printer in sequence according to the page number, wherein the cloud server does not check the host attribute value of the HTTP packet header in the network packet when receiving the network packet;

[0054] Specifically, the cloud server receives all the restructured network packets, reorganizes all the network packets into print packets, separates the complete print work order information and layout files from the print packets according to the format agreed in the print protocol, and usually, according to the HTTP header processing agreement of the web server, if the host attribute value is not directed to the web server host name of itself, the packet will be discarded. Therefore, the cloud server used in the embodiment does not check the host attribute value in the HTTP header of the network packet when receiving the network packet.

[0055] According to the received printer available memory safety value, the complete layout file is reorganized into a plurality of split files with a size not exceeding the printer available memory safety value, and the specific steps include:

[0056] The file structure of the layout file is parsed, and a folder framework of the split file is generated according to the file structure, the folder framework including a page folder, a resource folder and a document information description file. For example, the layout file is an OFD document with a total of 100 pages, the OFD document is essentially a compressed package, the total folder OFD_File includes a Doc document and an OFD document information description file OFD.xml, the Doc document can be multiple, and in the embodiment, only one Doc document is included, the Doc document includes a page folder Pages, a resource folder Res and a Doc document information description file Document.xml, and the like. The OFD.xml is used to describe the entire OFD document, and there is only one OFD.xml file in an OFD document compressed package. The Document.xml is used to describe the Doc document to which it belongs. In the complete OFD document, the page folder Pages includes page folders Page_0 to Page_100 of all pages, and the resource folder Res includes local resources and public resources such as fonts, graphics and images. The 100-page OFD document is split into 10 new OFD documents, each of which contains 10 pages of document content in page code order. According to the file structure of the above OFD document, the folder framework of each reorganized new OFD document is constructed, for example, the folder framework of the first new OFD document OFD_1 containing 0-10 pages is constructed, including a folder Doc_1 and an OFD document information description file OFD.xml. The folder Doc_1 includes a page folder Pages, a resource folder Res and a Doc document information description file Document.xml, and the like. The page folder Pages includes page folders Page_0 to Page_10 of 0-10 pages.

[0057] Extracting the content in the layout file except the page folder, copying and placing it in the folder outside the page folder of the split file; for example, extracting OFD.xml from the complete OFD document and directly placing it in the total folder OFD_1 of the split file, and extracting the local resources and public resources except the page folder Pages and copying and placing them in the resource folder Res of the folder Doc_1;

[0058] Extracting part of the page content in the layout file in the page code order, copying and placing it in the page folder; for example, extracting all the content in the page folder Page_0 to Page_10 from the complete OFD document, and copying and placing it in the page folder Page_0 to Page_10 in the folder Doc_1;

[0059] Checking whether the size of the split file exceeds the safe value of the available memory of the printer, if yes, reducing the number of pages contained in the split file until the size thereof does not exceed the safe value of the available memory of the printer; if the split file is too small, more pages can be placed in the split file until the size thereof does not exceed the safe value of the available memory of the printer, avoiding the decrease of the transmission efficiency due to the too fine splitting, and preferably, according to the public resource ID referenced in the page folder, the resources irrelevant to the extracted part of the page, such as the unused font, can be removed to further reduce the size of the split file;

[0060] According to the page content of the split file, modifying the basic information about the current document in OFD.xml and Document.xml, for example, if the new OFD document contains 10 pages, the number of pages in OFD.xml is modified to 10;

[0061] Renaming the split file according to the page code, for example, renaming the new OFD document OFD_1 containing 0-10 pages to print0-10.ofd, renaming the new OFD document OFD_2 containing 11-20 pages to print11-20.ofd, and sequentially sending the same to the printer after being packaged and ordered according to the page code.

[0062] Thus, by analyzing the layout file structure to extract and recombine the split file, the memory occupied by each split file is reduced, and each split file retains complete page information such as coordinates, fonts and graphics, which can effectively avoid the content disorder caused by cross-page splitting.

[0063] In step S103, the printer receives the split file sent by the cloud server, and constructs a print task for each split file according to the print work order information.

[0064] Specifically, after receiving the packaged segmented files, the printer constructs new print job tasks for each packaged segmented file according to the original print order and prints, for example, the original print order content is to print pages 9-15, and print 5 copies, the first print job task is constructed: print pages 9-10 in print0-10.ofd, print 5 copies, and send to the printer to complete printing; the second print job task is constructed: print pages 11-15 in print11-20.ofd, print 5 copies, and send to the printer to complete printing, until all segmented files are processed.

[0065] Further, the printer is prone to cause garbled characters or unable to print due to the lack of a font library, and the format file needs to be embedded with a font file according to a standard to ensure that the printer can print without relying on a local font library, but if the format file is not embedded with a font, the cloud server can parse characters by using a stored font library such as a TTF font library, and increase font data of the font library to the segmented file of the format file, and the cloud server can also complete a computing-intensive task such as font library parsing, which can also greatly reduce the memory occupation of the printer.

[0066] In addition, the print method of the embodiment needs the printer to be connected to a network, and the user agrees that the print content is sent to the supplier cloud server in necessary cases, and all transmissions are in a secure transmission mode.

[0067] The print method of the embodiment provided by the present application can process a super large format file by combining a printer and a cloud server, determine the size of the format file through a network message, enable the cloud server to assist in printing when the format file exceeds a safe value of the available memory of the printer, forward the network message to the cloud server while receiving, avoid the complete residence of the print file in the memory of the printer, avoid the risk of memory overflow, break through the limitation of the memory of the printer, and realize the printing of the super large format file; the cloud server recombines the super large format file into segmented files based on the structure of the format file, removes irrelevant resources according to the public resource ID referenced by the pages of the segmented files, and realizes that the segmented files maintain the integrity of independent printing and the resource reduction for reducing the file size; the print task is reconstructed into a sub-printing task of each segmented file according to the print order information obtained by the network message, the printer receives and prints the segmented files in sequence, the user perceives continuous work, and manual intervention is not needed. The print method provided by the embodiment breaks through the limitation of the memory of the printer, realizes the printing of the super large format file, and does not need the user to interact with the cloud server, thereby guaranteeing the user experience.

[0068] Referring to Figure 2 Another embodiment of the present application also provides a print system 200 of a super large format file based on a cloud service, which comprises a print client 210, a printer 220, and a cloud server 230, and the system 200 can execute the print method in the method embodiment.

[0069] Specifically, the print client 210 is configured to send print message data, which is divided into a plurality of network messages, to the printer;

[0070] The printer 220 comprises a print service interface 221, an analysis module 222, a forwarding module 223 and a print processing module 224. The print service interface 221 is configured to receive the print message data, which is divided into a plurality of network messages, sent by the print client 210. The analysis module 222 is configured to obtain the size of a layout file to be printed from the network messages according to a print protocol, and obtain print order information from the network messages if the size of the layout file exceeds a preset printer available memory safety value. The forwarding module 223 is configured to establish a connection with the cloud server 230, send the network messages after reconstruction to the cloud server 230, and send the printer available memory safety value to the cloud server 230. The print processing module 224 is configured to receive the segmented files sent by the cloud server 230, and construct a print task for each segmented file according to the print order information.

[0071] The cloud server 230 comprises a large file processing service interface 231 and a layout file segmentation tool 232. The large file processing service interface 231 is configured to receive the reconstructed network messages and the printer available memory safety value sent by the printer, recombine all the network messages into a print message, and separate the layout file from the print message. When receiving the network messages, the large file processing service interface does not check the host attribute value of the HTTP packet header in the network messages. The layout file segmentation tool 232 is configured to recombine the layout file into a plurality of segmented files according to the printer available memory safety value. The size of each segmented file does not exceed the printer available memory safety value. The segmented files are renamed according to page numbers, packaged, and sent to the printer in sequence according to the page number order.

[0072] Further, the forwarding module 223 is further configured to:

[0073] modify the source port of the TCP header of each network message to a local port of the printer, modify the destination port to a service port of the cloud server, recalculate and update the checksum of the TCP header,

[0074] modify the source IP address of the IP header of each network message to an IP address of the printer, modify the destination IP address to an IP address of the cloud server, recalculate and update the checksum of the IP header,

[0075] send the reconstructed network messages to the cloud server, and delete the network messages that have been processed and successfully sent,

[0076] Further, the layout file splitting tool 232 is further configured to:

[0077] analyzing a file structure of the layout file, and generating a folder framework of the split file according to the file structure, the folder framework comprising a page folder, a resource folder and a document information description file;

[0078] extracting contents from the layout file except the page folder, and copying the extracted contents into folders of the split file except the page folder;

[0079] extracting partial page contents from the layout file in page number order, and copying the extracted partial page contents into the page folder;

[0080] checking whether a size of the split file exceeds a safe value of available memory of the printer, and if so, reducing a number of pages contained in the split file until the size of the split file does not exceed the safe value of available memory of the printer;

[0081] modifying the document information description file of the split file according to page contents of the split file.

[0082] Further, the layout file splitting tool 232 is further configured to:

[0083] removing public resources irrelevant to the partial page contents according to public resource IDs referenced by the partial page contents.

[0084] It should be noted that the printing system provided in the embodiment corresponds to a technical solution that can be used to execute the method embodiments, and has similar implementation principles and technical effects, which will not be described here.

[0085] The above description is merely preferred embodiments of the present application. It should be understood by those skilled in the art that the disclosed scope of the present application is not limited to the technical solutions formed by the specific combinations of the above technical features, and should also cover other technical solutions formed by any combinations of the above technical features or equivalent features without departing from the disclosed concept. For example, the above features can be replaced with other features disclosed in the present application (but not limited to) having similar functions to form technical solutions.

Claims

1. A cloud service-based method of printing a large-format file, characterized by, The printer receives the print message data sent by the print client, the print message data being divided into multiple network messages, obtains the size of a print format file to be printed from the network messages according to a print protocol, and if the size of the print format file exceeds a preset printer available memory safety value, the printer obtains print job information from the network messages, reconstructs the network messages and sends the reconstructed network messages to a cloud server, and sends the printer available memory safety value to the cloud server. The cloud server receives the reconstructed network messages and the printer available memory safety value sent by the printer, recombines all the network messages into a print message, separates a print format file from the print message, and recombines the print format file into a plurality of split files according to the printer available memory safety value, including: analyzing a file structure of the print format file, generating a folder framework of the split file according to the file structure, the folder framework including a page folder, a resource folder and a document information description file, extracting contents other than the page folder from the print format file, copying and placing the contents into folders other than the page folder of the split file, extracting partial page contents from the print format file in page number order, copying and placing the partial page contents into the page folder, checking whether the size of the split file exceeds the printer available memory safety value, and if so, reducing the number of pages included in the split file until the size of the split file does not exceed the printer available memory safety value, modifying the document information description file of the split file according to the page contents of the split file, and renaming the split file according to page numbers, packaging the split file and sending the split file to the printer in page number order, wherein the cloud server does not check a host attribute value of an HTTP header of the network message when receiving the network message. The printer receives the split file sent by the cloud server and constructs a print task for each split file according to the print job information. The step of reconstructing the network message and sending the reconstructed network message to the cloud server includes:

2. The cloud service-based printing method of a super large format file according to claim 1, characterized in that, modifying a source port of a TCP header of each network message to a local port of the printer, modifying a destination port to a service port of the cloud server, recalculating and updating a checksum of the TCP header, modifying a source IP address of an IP header of each network message to an IP address of the printer, modifying a destination IP address to an IP address of the cloud server, recalculating and updating a checksum of the IP header, sending the reconstructed network message to the cloud server, and deleting the network message that has been processed and successfully sent. Further including removing public resources irrelevant to the partial page contents according to a public resource ID referenced by the partial page contents. 3.The cloud service-based printing method of a super large format file according to claim 1, wherein, The public resources include fonts, graphics and images.

4. The cloud service-based printing method of a super large format file according to claim 3, characterized in that, Further including:

5. The cloud service based printing method of a super large format file according to claim 1, wherein, The cloud server analyzes characters of the print format file using a font library stored by the cloud server, and adds font data of the fonts to the split file of the print format file. The print client sends print message data divided into multiple network messages to the printer.

6. A cloud service-based printing system for large format files, characterized by, The printer includes a print service interface, an analysis module, a forwarding module and a print processing module. ​ ​ The print service interface is configured to receive print message data sent by a print client, the print message data being split into a plurality of network messages; the analysis module is configured to obtain the size of a layout file to be printed from the network messages according to a print protocol, and obtain print job information from the network messages if the size of the layout file exceeds a preset printer available memory safety value; and the forwarding module is configured to establish a connection with a cloud server, send the network messages after reconstruction to the cloud server, and send the printer available memory safety value to the cloud server. The print processing module is configured to receive segmented files sent by the cloud server, and construct a print task for each of the segmented files according to the print job information. The cloud server comprises a large file processing service interface and a layout file segmentation tool. The large file processing service interface is configured to receive the network messages after reconstruction and the printer available memory safety value sent by the printer, recombine all the network messages into a print message, separate a layout file from the print message, and not check a host attribute value of an HTTP packet header in the network messages when receiving the network messages. The layout file segmentation tool is configured to recombine the layout file into a plurality of segmented files according to the printer available memory safety value, comprising: analyzing a file structure of the layout file, generating a folder framework of the segmented files according to the file structure, the folder framework comprising a page folder, a resource folder and a document information description file; extracting contents other than the page folder from the layout file, copying and placing the contents into folders other than the page folder of the segmented files; extracting partial page contents from the layout file in page number order, copying and placing the partial page contents into the page folder; checking whether the size of the segmented files exceeds the printer available memory safety value, and if so, reducing the number of pages contained in the segmented files until the size of the segmented files does not exceed the printer available memory safety value; modifying the document information description file of the segmented files according to the page contents of the segmented files; and renaming the segmented files according to page numbers, packaging the segmented files and sending the segmented files to the printer in page number order, wherein the size of the segmented files does not exceed the printer available memory safety value.

7. The cloud service based printing system of very large format files as claimed in claim 6 wherein, The forwarding module is further configured to: modify a source port of a TCP header of each network message to a local port of the printer, modify a destination port to a service port of the cloud server, recalculate and update a checksum of the TCP header; modify a source IP address of an IP header of each network message to an IP address of the printer, modify a destination IP address to an IP address of the cloud server, recalculate and update a checksum of the IP header; send the network messages after reconstruction to the cloud server, and delete the network messages that have been processed and successfully sent. 8.The cloud service-based printing system of a super large format file according to claim 6, wherein, The layout file segmentation tool is further configured to remove public resources irrelevant to the partial page contents according to public resource IDs referenced by the partial page contents.

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