JP6768279B2 - Printing equipment and programs - Google Patents

Description

The present invention relates to a printing device and a program that execute printing based on print target data.

As a method for printing the print data received from the outside by a printing device such as an inkjet printer, there are a direct printing method in which the received print data is directly transferred to the print processing unit and printed, and a hard disk drive (the received print data is once transferred to the hard disk drive ( A spool method is widely known in which printing is performed after storing in a storage device such as HDD). Hereinafter, printing by the direct printing method is referred to as direct printing. Printing by the spool method is called spool printing.

If the direct printing method is used when the data reception speed is slow, the data reception may not catch up during printing, and printing may be stopped due to waiting for reception. Unexpected print stop affects transport control and print control, and may cause deterioration of the image quality of printed matter. For example, if an unexpected wait occurs between scanning and transfer in the printing process of the ink ejection method, the ink may not be properly overlapped due to drying of the ink, and color development failure may occur. In addition, the paper may warp due to the stop of transportation. The spool method is an effective printing method in such a case. In the spool method, the printing device first stores all the received print data in a storage device such as an HDD having a sufficient data transfer rate. After that, the printing device transfers the print data stored in the HDD to the print processing unit. As a result, printing stop due to waiting for reception is avoided. However, since the spool printing method starts printing after receiving the print data, the printing completion is delayed as compared with the direct printing method. Therefore, when the data reception speed is sufficiently high, it is desirable to select the direct printing method. In this way, when printing print data received from the outside, it is desirable to determine the data reception speed and select the printing method according to the determination result.

Patent Document 1 describes a technique for switching the print data to be transmitted based on the communication speed of the communication interface used for transmitting the print data in the device for transmitting the print data. Further, Patent Document 1 describes a method of determining the communication speed of the communication interface based on whether or not the communication interface to be used is a high-speed communication interface.

However, even if the communication interface used is a high-speed communication interface, the data reception speed may decrease depending on the communication content. For example, in a communication in which communication data is encrypted, such as secure communication (for example, communication by TLS (Transport Layer Security)), it is necessary to decrypt the encrypted communication data, so that the data is substantially printed. The data reception speed in the device decreases. Therefore, even if the direct printing method is selected in an environment that uses a high-speed communication interface, data reception waiting occurs depending on the communication content and the printing operation is interrupted, resulting in deterioration of image quality as in the case of using a low-speed communication interface. There is a risk of inviting.

Japanese Patent No. 3907484

Therefore, an object of the present invention is to provide a printing device and a program capable of preventing deterioration of image quality due to waiting for reception of print data.

The printing apparatus according to the present invention is a printing apparatus that executes printing based on print target data, and is a receiving means for receiving the print target data and a communication method used for receiving the print target data by the receiving means. The printing means is provided with a printing means for executing printing of the print target data based on the security conditions of the above, and the communication method used for receiving the print target data is a predetermined secure communication method . When the length of the public key in the predetermined secure communication method is equal to or longer than the predetermined length , the first printing method of printing the print target data after the print target data is received by the receiving means is executed. When the communication method is not the predetermined secure communication method, the reception is after the reception of a part of the print target data by the receiving means and before the reception of the other part of the print target data. It is characterized by executing a second printing method of printing a part of the printed material.

According to the present invention, it is possible to prevent deterioration of image quality due to waiting for reception of print data.

It is a block diagram which shows an example of the structure of the printing system including the printing apparatus by this invention. It is a block diagram which shows the hardware structure of the printing apparatus according to this invention. It is a block diagram which shows the software structure of the printing apparatus by this invention. It is explanatory drawing which shows typically the process from the start of a reception process to the completion of a print process. It is a flowchart which shows the process at the time of receiving a print job in the printing apparatus of 1st Example. It is a flowchart which shows the process at the time of receiving a print job in the printing apparatus of 2nd Example. It is explanatory drawing which shows the mode that the received data is processed in the printing apparatus of 3rd Example. It is a flowchart which shows the process at the time of receiving a print job in the printing apparatus of 3rd Example.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The configuration shown in the following examples is only an example, and the present invention is not limited to the illustrated configuration.

[Example 1]
FIG. 1 is a block diagram showing an example of the configuration of a printing system including the printing apparatus according to the present invention. The printing system shown in FIG. 1 includes a printing device 1 according to the present invention and printing job input devices 2 and 3. The printing device 1 and the printing job input devices 2 and 3 are connected via a local area network (LAN) 4. Although one printing device is illustrated in FIG. 1, the printing system may include any number of printing devices. Further, although FIG. 1 illustrates two print job input devices, the print system may include any number of print job input devices.

The printing device 1 has a plurality of types of LAN interfaces. The printing device 1 communicates with the printing job input devices 2 and 3 on the LAN 4 via a plurality of types of LAN interfaces.

The print job input devices 2 and 3 instruct the desired printing device on the LAN 4 to print.

FIG. 2 is a block diagram showing a hardware configuration of a printing apparatus according to the present invention.

As shown in FIG. 2, the printing device 1 according to the present invention includes a RAM 10, a ROM 11, a CPU 12, a LAN controller 13, an HDD 14, a cryptographic processing unit 15, a print processing unit 18, and a wired LAN interface (wired LAN). The I / F) 16 and the wireless LAN interface (wireless LAN I / F) 17 are included. The RAM 10, ROM 11, CPU 12, LAN controller 13, HDD 14, encryption processing unit 15, and print processing unit 18 are connected to each other via the system bus 19.

The CPU 12 comprehensively controls various devices connected to the system bus 19 based on the control program on the ROM 11.

The ROM 11 stores a control program or the like that can be executed by the CPU 12.

The RAM 10 mainly functions as a main memory, a work area, and the like of the CPU 12.

The LAN controller 13 controls the wired LAN interface 16 and the wireless LAN interface 17 of the printing device 1 to connect to the LAN 4 and communicate with an external device via the LAN 4. In this embodiment, the printing device 1 communicates with an external device on the LAN 4 via the LAN controller 13. For example, the printing device 1 receives a print job from the print job input devices 2 and 3 via the LAN controller 13.

The encryption processing unit 15 decrypts the encrypted data among the data received from the external device by the LAN controller 13. The encryption processing unit 15 may be realized by a circuit mounted on the substrate of the printing device 1, or may be realized by an encryption processing program developed on the ROM 11 or the RAM 10 instead of the hardware. In this embodiment, the TLS / SSL (Transport Layer Security / Security Sockets Layer) protocol is used for data encryption. The TLS / SSL protocol may be implemented on the LAN interface or control program of the printing device 1 based on TLS1.2 defined in RFC5246, or may be implemented based on TLS1.2 or a later version. .. A protocol other than the TLS / SSL protocol may be used for data encryption.

In order to identify whether or not the communication content is encrypted by the TLS / SSL protocol, a method of storing information about the TLS / SSL protocol in the RAM 10 and referring to the information at the time of communication may be used. Alternatively, a method of determining whether or not the LAN port is a port assigned to communication by the TLS / SSL protocol (hereinafter referred to as TLS / SSL communication) may be used from the number of the LAN port used for communication. ..

The print processing unit 18 executes the print process based on the received print job. The print processing unit 18 forms an image by ejecting ink while moving an ink ejection unit (recording head) (not shown) perpendicularly to the paper transport direction. The ink ejection pattern is formed by the image processing task 29 described later. Specifically, the image processing task 29 analyzes the print target data (image data in this embodiment) included in the received print job, and forms an ink ejection pattern based on the analysis result. Further, in this embodiment, the discharge pattern is formed in units of one head movement (one scan). The RAM 10 is used as a buffer during image data processing and ejection pattern formation.

Access to the HDD 14 is controlled by an HDD control program stored on the ROM 11. The HDD 14 is used as a job storage area for temporarily spooling the received print job. The spooled print job can be controlled from the outside of the printing device 1. A storage device other than the HDD may be used as the job storage area.

FIG. 3 is a block diagram showing a software configuration of the printing apparatus according to the present invention. In this embodiment, a program for controlling each domain shown in FIG. 3 is stored in the ROM 11 or RAM 10, and when the CPU 12 loads and executes the program, each domain shown in FIG. 3 functions. To do. In this embodiment, the tasks included in each domain are operated by an OS (Operating System) 28 conforming to the μItron standard.

The system control domain 20 is in charge of the state transition of the entire device.

The print control domain 21 includes a job control task 22, a print engine control task 23, and an image processing task 29. The print control domain 21 performs job processing and hardware control of the print processing unit 18 by these tasks.

The communication control domain 24 includes a network control task 25 and a communication data control task 26. The communication control domain 24 controls the communication between the printing device 1 and the external device by these control tasks. The communication control domain 24 also includes a software cryptographic library 27.

The network control task 25 connects to the LAN 4 and communicates via the LAN 4. The network control task 25 has a function of identifying the LAN interface currently communicating. As a method of identifying the LAN interface, for example, when each LAN interface is operated exclusively, information indicating a single LAN interface currently being operated is stored in the RAM 10 and the information is statically referred to. There are methods and so on. Further, for example, when each LAN interface can communicate at the same time, the LAN controller 13 sets an identifier, for example, an IP address for each LAN interface individually, and determines the LAN interface currently communicating from the destination of the communication packet. There is. The network control task 25 may be realized by the CPU included in the LAN controller 13.

The communication data control task 26 cooperates with the network control task 25 to receive data sent from the external device to the printing device 1. When it is necessary to decode the received data, the communication data control task 26 decodes the received data by hardware or software. In this embodiment, the communication data control task 26 uses the cryptographic processing unit 15 or the software cryptographic library 27 to multiplex the received data. Further, in the present embodiment, the communication data control task 26 determines whether or not to use the secure communication method as the communication method in the communication with the external device based on the request from the external device in accordance with TLS 1.2. To do.

The software encryption library 27 is a software library that mainly encrypts and decrypts communication data. The software cryptographic library 27 decrypts a cipher that the cryptographic processing unit 15 cannot decrypt. In this embodiment, the printing device 1 performs encryption processing by hardware and encryption processing by software, but either encryption processing may be performed.

FIG. 4 is an explanatory diagram schematically showing the process from the start of the reception process to the completion of the print process. FIG. 4 shows how the received image data is processed sequentially (in numerical order shown in FIG. 4) for each block. In FIG. 4, the horizontal direction (t direction) represents the time lapse of each process (reception process, decoding process, image process, and print process) since the print job was submitted.

Normally, the image processing task 29 forms an ejection pattern from the image data faster than the printing processing unit 18 actually moves the head under the control of the printing engine control task 23 to eject ink. Therefore, as shown in FIG. 4A, the print processing unit 18 can continuously execute the head movement and the ink ejection. However, as shown in FIG. 4B, when the data reception, which is the first stage of the image data processing, is slow, the image processing such as the ejection pattern formation in the image processing task 29 is awaited due to the delay in the data reception. As a result, the print processing unit 18 cannot start the print process until the next ejection pattern is formed. In the ink ejection method printing process, it is not desirable that an unexpected wait occurs between scanning and conveying. The reason is that, as described above, the waiting time between scanning and conveying causes deterioration of the image quality of the printed image.

FIG. 4C shows an example in which the image data of the print job is spooled to the HDD 14 and printed when the reception speed is slow as in FIG. 4B. In the example shown in FIG. 4C, the printing device 1 first stores the image data of the print job received from the LAN controller 13 in the HDD 14, and starts printing after all the image data of the print job is stored. .. At the time of printing, the printing device 1 transfers the image data of the print job from the HDD 14 to the RAM area used by the image processing task 29. The data transfer from the HDD 14 to the RAM 10 is faster than the processing speed of the image processing task 29 and the print processing unit 18, so that the image processing task 29 and the print processing unit 18 do not have to wait. Therefore, the printing process in the printing processing unit 18 is not interrupted until all printing is completed. However, comparing FIGS. 4 (c) and 4 (b), the spool printing method takes more time from the start of job reception to the end of printing than the direct printing. If all printing is to be performed by the spool printing method, it takes a long time to perform all printing, so it is desirable that spool printing is executed only when necessary.

FIG. 5 is a flowchart showing a process at the time of receiving a print job in the printing apparatus of the first embodiment.

First, when the communication data control task 26 detects the reception of the print job, the decode flag is initialized (step S100). The decode flag is used to determine whether or not to decrypt the encrypted received data. The decode flag is managed by the communication control domain 24 and stored in the RAM 10. The initial value of the decode flag is OFF. Next, the communication data control task 26 inquires the network control task 25 which communication interface is the communication interface that received the print job (step S101).

When the reception path of the print job is a wireless LAN, that is, when the communication interface that received the print job is the wireless LAN interface 17 (YES in step S101), the communication data control task 26 is the communication interface. It is determined that the communication speed is equal to or lower than the predetermined speed. Then, the communication data control task 26 determines that the data reception processing capacity is lower than the print processing capacity, and determines that spool printing is performed. When the data reception processing capacity is lower than the print processing capacity, for example, the sum of the data reception time (when the received data is encrypted, the data reception time and the time required for the decryption processing of the received data). ) Exceeds the print processing time. When the communication data control task 26 determines that spool printing is to be performed, the image data of the print job is stored in the HDD 14 as a predetermined spool process. When all the image data of the print job is stored in the HDD 14, the communication data control task 26 requests the print control domain 21 to start processing the print job. Then, the communication data control task 26 sequentially transfers the image data from the HDD 14 to the print control domain 21 waiting for the transfer of the image data. As a result, the job process and the print process are executed in the print control domain 21 (step S104).

If the communication interface that received the print job is not the wireless LAN interface 17 (NO in step S101), the communication data control task 26 confirms the communication method (step S102). In this embodiment, when TLS authentication is used for communication with the external device in the process of step S102, the communication data control task 26 determines that TLS is effective, and the communication method in the communication is secure. Judge that it is a communication method.

When the communication method is a secure communication method (YES in step S102), the communication data control task 26 determines that it is necessary to decode the received data in the subsequent processing, and sets the decoding flag to ON (step). S103). At this time, the communication data control task 26 determines that the data reception processing capacity is lower than the print processing capacity, and determines that spool printing is performed. Then, the communication data control task 26 decrypts the encrypted received data by using the software encryption library 27 or the encryption processing unit 15, and stores the decrypted data in the HDD 14. Then, in the process of step S104, spool printing is performed. As shown in FIG. 4D, when decoding the received data, the time from the start of data reception to the start of image processing becomes longer due to the time required for the decoding process, and the print processing unit 18 waits. In order to avoid the occurrence of such a wait, as described above, in this embodiment, when the communication method is the secure communication method, spool printing is performed. As shown in FIG. 4D, when each process is performed in block units, the communication data control task 26 confirms the decode flag at the start of the reception process of the next block, and the decode flag. When is ON, the next block is decrypted.

If the communication method is not the secure communication method (NO in step S102), the communication data control task 26 determines that printing is to be performed directly, and requests the print control domain 21 to start processing the print job. When the print control domain 21 receives the request to start processing, it controls the job control task 22 and the print engine control task 23, and transitions to a state in which the transfer of image data of the print job can be accepted. The print control domain 21 executes job processing and printing processing when the transfer of image data from the communication control domain 24 is started (step S105).

As described above, in the present embodiment, spool printing is performed not only when the communication path is low speed but also when the data reception speed is substantially slowed down by encryption even if the communication path is high speed. Apply. As a result, it is possible to prevent an unexpected print stop. Therefore, according to the present embodiment, in a printing apparatus that prints print data received from the outside, it is possible to prevent deterioration of image quality due to waiting for reception of the print data. Further, in the present embodiment, when the communication path is high speed and the print data is not encrypted, direct printing is applied, so that the printing speed is not lowered more than necessary.

[Second Example]
Since the configuration of the printing apparatus in the second embodiment is the same as the configuration of the printing apparatus in the first embodiment, the description thereof will be omitted. The operation of the printing apparatus in this embodiment will be described below.

FIG. 6 is a flowchart showing a process at the time of receiving a print job in the printing apparatus of the second embodiment. Since the processes of steps S200 to S205 shown in FIG. 6 are the same as the processes of steps S100 to S105 shown in FIG. 5, the description thereof will be omitted. In this embodiment, the communication data control task 26 determines the encryption strength of secure communication after setting the decoding flag in the process of step S203 (step S206).

When the encryption strength of the secure communication is higher than the predetermined strength (YES in step S206), the communication data control task 26 determines that the time required for the decryption process becomes longer and the data reception processing capacity becomes lower than the print processing capacity. Then, it is determined that spool printing is performed. Then, the spool printing process is performed in the process of step S204. The reason is that when the encryption strength of secure communication is higher than a predetermined strength, the sum of the data reception time and the time required for the decryption processing by the software encryption library 27 or the encryption processing unit 15 is the processing of the printing processing unit 18. This is because it may exceed the time. In this embodiment, the communication data control task 26 determines that the encryption strength is equal to or greater than a predetermined strength when the length of the public key in the TLS / SSL communication is 2048 bits or more. The communication data control task 26 may determine that the encryption strength is equal to or higher than a predetermined strength when any one of ECDHE, AES, GCM, and SHA386 is used as the communication encryption algorithm, and other determination methods. May be used.

When the encryption strength of the secure communication is equal to or less than a predetermined strength (NO in step S206), the communication data control task 26 determines that printing is to be performed directly, and requests the print control domain 21 to start processing the print job. .. Then, direct printing is performed in the process of step S205.

According to this embodiment, it is possible to determine in more detail whether or not the print job needs to be spooled, and it is possible to more reliably prevent deterioration of image quality due to waiting for reception of print data.

[Third Example]
Since the configuration of the printing apparatus in the third embodiment is the same as the configuration of the printing apparatus in the first embodiment, the description thereof will be omitted. However, in this embodiment, the cryptographic processing unit 15 has a hardware cryptographic accelerator. A hardware cryptographic accelerator is hardware that performs cryptographic processing at high speed.

Here, the flow of received data in the printing apparatus will be described. FIG. 7 is an explanatory diagram showing how the received data is processed in the printing apparatus of the third embodiment. The arrow shown in FIG. 7 indicates the direction in which the data flows. The receive buffer 71, the intermediate buffer 72, and the print buffer 76 correspond to the RAM 10. Further, the HDD 75 corresponds to the HDD 14. The software cryptographic library 74 corresponds to the software cryptographic library 27. Further, the hardware cryptographic accelerator 73 corresponds to the hardware cryptographic accelerator included in the cryptographic processing unit 15.

As shown in FIG. 7, the received data stored in the receive buffer 71 is transferred to the intermediate buffer 72. When the received data stored in the intermediate buffer 72 is encrypted, in this embodiment, the printing device 1 decrypts the received data by the hardware cryptographic accelerator 73 or the software cryptographic library 74. Since the cryptographic processing using the hardware cryptographic accelerator 73 is sufficiently fast, it does not cause the printing apparatus 1 to wait for printing. The reason is that the sum of the data reception time and the time required for the decryption process by the hardware cryptographic accelerator 73 may not exceed the processing time of the print processing unit 18. Therefore, the received data decrypted by the hardware cryptographic accelerator 73 is directly transferred to the print buffer 76. On the other hand, the received data decrypted by the software encryption library 74 is spooled to the HDD 75 and then transferred to the print buffer 76. The hardware cryptographic accelerator 73 can decrypt data encrypted by a predetermined cryptographic algorithm. Therefore, the received data encrypted by a predetermined encryption algorithm is decrypted by the hardware encryption accelerator 73, and the received data encrypted by other encryption algorithms is decrypted by the software encryption library 27.

FIG. 8 is a flowchart showing a process at the time of receiving a print job in the printing apparatus of the third embodiment. Since the processes of steps S300 to S305 shown in FIG. 8 are the same as the processes of steps S200 to S205 shown in FIG. 6, the description thereof will be omitted. In this embodiment, the communication data control task 26 uses the hardware cryptographic accelerator of the cryptographic processing unit 15 or the software cryptographic library 27 based on the type of cryptographic algorithm after setting the decoding flag in the process of step S303. (Step S306).

If it is determined to use the software cryptographic library 27 for the cryptographic process (YES in step S306), the spool print process is performed in the process of step S304. If it is determined to use the hardware cryptographic accelerator of the cryptographic processing unit 15 (NO in step S306), the communication data control task 26 determines that printing is to be performed directly, and starts processing the print job in the print control domain 21. Request. Then, direct printing is performed in the processing of Tep S305.

According to this embodiment, in addition to determining the communication interface and communication method of the received print job, it is determined whether or not the print job needs to be spooled based on the cryptographic processing module to be operated. As a result, it becomes possible to determine the necessity of spooling the print job in more detail, and the same effect as that of the second embodiment can be obtained.

(Other Examples)
The present invention supplies a program that realizes one or more functions of the above-described embodiment to a system or device via a network or storage medium, and one or more processors in the computer of the system or device reads and executes the program. It can also be realized by the processing to be performed. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

21 Print control domain 24 Communication control domain

Claims (10)

A printing device that performs printing based on print target data.
A receiving means for receiving the print target data and
A printing means for executing printing of the printing target data based on the security conditions of the communication method used for receiving the printing target data by the receiving means is provided.
The printing means
When the communication method used for receiving the print target data is a predetermined secure communication method and the length of the public key in the predetermined secure communication method is a predetermined length or more , the printing by the receiving means is performed. After receiving the target data, the first printing method of printing the print target data is executed, and when the communication method is not the predetermined secure communication method, the receiving means receives a part of the print target data. A printing apparatus characterized in that a second printing method of printing the received portion is executed later, before the reception of the other portion of the print target data. A printing device that performs printing based on print target data.
A receiving means for receiving the print target data and
A printing means that executes printing of the printing target data based on the security conditions of the communication method used for receiving the printing target data by the receiving means, and
It is provided with a decryption processing means for decrypting received data encrypted by a secure communication method using a hardware cryptographic accelerator or a software cryptographic library.
The printing means
When the communication method used for receiving the print target data is a predetermined secure communication method and the decryption process is performed using the software encryption library, the print target data is received by the receiving means and then the print target data is received. Execute the first printing method to print the data to be printed,
When the communication method is not the predetermined secure communication method, or when the communication method is the predetermined secure communication method and the decryption process is performed using the hardware cryptographic accelerator, the print target by the receiving means. A printing apparatus characterized in that a second printing method of printing the received part is executed after the reception of a part of the data and before the reception of the other part of the data to be printed. .. The printing means is based on the conditions relating to the communication interface used for reception by the receiving means, regardless of whether or not the communication method used for receiving the print target data is the predetermined secure communication method. The printing apparatus according to claim 1 or 2 , wherein the first printing method is performed. The printing apparatus according to claim 3 , wherein the condition relating to the communication interface is a condition relating to a reception speed in receiving the print target data by the receiving means. The receiving means includes a first communication interface and a second communication interface.
The printing apparatus according to claim 3 or 4 , wherein the condition relating to the communication interface includes that the communication interface used for reception by the receiving means is not the first communication interface. The printing apparatus according to claim 5 , wherein the first communication interface is a wireless interface, and the second communication interface is a wired interface. The printing apparatus according to claim 6 , wherein the first communication interface is a wireless LAN interface, and the second communication interface is a wired LAN interface. Even if the communication method used for receiving the print target data is the predetermined secure communication method, the printing means is described in the case where the encryption strength in the predetermined secure communication method is lower than the predetermined strength. The printing apparatus according to any one of claims 1 to 7 , wherein the printing method of 2 is executed. In the first printing process, the printing unit, the print data spooled in the storage device included in the printing apparatus, according to claim 1 to 8, wherein the printing the print target data the spool The printing apparatus according to any one of the above items. A program that causes a computer to function as each means of the printing apparatus according to any one of claims 1 to 9 .

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