JP2021132340A - Image forming apparatus - Google Patents

Abstract

To obtain an image forming apparatus that can easily detect alteration of a document.SOLUTION: An image output unit 22 generates image data for image output of a document image, acquires a time stamp corresponding to the image data for image output, generates a hash value of the image data for image output to which the time stamp is added, processes the image data for image output in a processing mode corresponding to the hash value, and executes image output (printing, transmission of image data file, and the like) for the image data for image output after the processing by using a printer device 11 and a communication device.SELECTED DRAWING: Figure 1

Description

The present invention relates to an image forming apparatus.

A certain image processing apparatus generates a time stamp based on the image data of a document, embeds the time stamp in the image data, and generates the image data with the time stamp (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2008-141692

However, if the time stamp of the image data of the falsified document is generated after the falsification of the document and the time stamp is embedded in the image data to generate the image data with the time stamp, the falsification of the document is difficult to detect. turn into.

The present invention has been made in view of the above problems, and an object of the present invention is to obtain an image forming apparatus that can easily detect falsification of a document.

The image forming apparatus according to the present invention generates image data for image output of a document image with a printing device, a communication device, prints an image with the printing device based on the image output image data, and outputs a print product. It also includes an image output unit that transmits the image data for image output as an image data file using the communication device and executes image output. Then, the image output unit (a) acquires a time stamp corresponding to the image output image data, and (b) generates a hash value of the image output image data to which the time stamp is added, and (c) ) The image data for image output is processed in a processing mode corresponding to the hash value, and (d) the image output is executed for the image data for image output after processing.

According to the present invention, an image forming apparatus capable of easily detecting falsification of a document can be obtained.

The above or other objects, features and advantages of the present invention will be further clarified from the following detailed description along with the accompanying drawings.

FIG. 1 is a block diagram showing a configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a diagram showing an example of a processing mode used in the image forming apparatus 1 shown in FIG. FIG. 3 describes the operation of the image forming apparatus 1 shown in FIG. 1 at the time of image output. FIG. 4 describes the operation of the image forming apparatus 1 shown in FIG. 1 at the time of output image verification.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a configuration of an image forming apparatus according to an embodiment of the present invention. The image forming apparatus 1 shown in FIG. 1 is a multifunction device and includes a printing apparatus 11, an image reading apparatus 12, an operation panel 13, a storage apparatus 14, a communication apparatus 15, and a controller 16.

The printing device 11 is an internal device that prints an image page by page on printing paper by an electrophotographic method or the like based on the printed image data. The image reading device 12 is an internal device that optically reads an image of a document such as a print product page by page and generates image data of each page image.

Further, the operation panel 13 is arranged on the surface of the housing of the image forming apparatus 1 and includes a display device for displaying various information to the user and an input device for detecting the user operation. As the display device, for example, a liquid crystal display is used. As an input device, a touch panel for hard keys and soft keys is used.

Further, the storage device 14 is a non-volatile storage device capable of storing various data and programs.

Further, the communication device 15 is a circuit that is connected to the computer network 2 and performs data communication with another device (time stamp server 3 or the like) connected to the computer network 2.

Further, the controller 16 has a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like, loads a program from the ROM, the storage device 14, and the like into the RAM, and loads the program into the RAM by the CPU. By executing it, it operates as various processing units. Here, the controller 16 operates as a control unit 21, an image output unit 22, and an output document image verification unit 23.

The control unit 21 receives a job request based on a user operation or the like, and executes the job specified by the job request by using an internal device such as a printing device 11 or an image reading device 12.

The image output unit 22 generates image data for image output of a document image, prints an image on the printing device 11 based on the image data for image output, and outputs a print product, or uses a communication device 15 to output an image. The image data for output is transmitted as an image data file and the image output is executed.

The image output unit 22 stores the image output image data and the time stamp in the storage device 14 for verification.

Further, the image output unit 22 (a) acquires a time stamp corresponding to the image output image data, (b) generates a hash value of the image output image data to which the time stamp is added, and (c) The image output image data (that is, the output document image) is processed in the processing mode corresponding to the hash value, and (d) the image output is executed for the processed image output image data.

In this embodiment, the image output unit 22 generates a hash value of the original image data for image output, and uses the communication device 15 to transmit the hash value to the time stamp server 3 to the time stamp server 3. Is issued a time stamp, and the time stamp is received from the time stamp server 3.

FIG. 2 is a diagram showing an example of a processing mode used in the image forming apparatus 1 shown in FIG. In this embodiment, for example, as shown in FIG. 2, the above-mentioned processing modes are (a) changing the character color of the document image according to the predetermined rule, and (b) changing the font size of the document image according to the predetermined rule. Change, (c) change the font time of the document image according to the predetermined rule, (d) insert the space between characters, the line spacing, or the space between paragraphs of the document image according to the predetermined rule, and (e) to the predetermined rule. It is one or a combination of one or more of the character orientation inversions of the following document images.

For example, for each type of processing mode, a plurality of change patterns and the number of inserted spaces are associated with a plurality of ranges of hash values in advance, and a time stamp is obtained based on data (table, etc.) indicating the correspondence. The number of insertions of change patterns and spaces corresponding to the hash value of the image data for image output to which is added is specified.

Further, the image output unit 22 specifies a character position corresponding to the hash value of the image output image data to which the above-mentioned time stamp is added in the text of the document image, and the above-mentioned processing mode is applied to the specified character position. May be processed.

As described above, in the above-mentioned processing mode, for example, as shown in FIG. 2, the text in the output document image is readable even after being processed in the processing mode.

The output document image verification unit 23 acquires (a) an output document image based on the print product or image data file obtained in the above-mentioned image output, and (b) saves the image data for image output and the time stamp. Based on, a reference image as a regular output document image is generated, and (c) the output document image and the output document image are verified based on the reference image.

For example, the output document image verification unit 23 acquires an output document image by reading the image of the print product obtained by the above-mentioned image output with the image reading device 12, or from a host device (not shown by the communication device 15). Receive the above-mentioned image data file and acquire the output document image.

Further, for example, the output document image verification unit 23 determines whether or not the image of the portion changed from the original document image matches each other in the output document image and the reference image based on the processing mode used. By doing so, the output document image is verified.

Next, the operation of the image forming apparatus 1 will be described.

(A) Operation at the time of image output

FIG. 3 describes the operation of the image forming apparatus 1 shown in FIG. 1 at the time of image output.

The image output unit 22 generates image data for image output according to the type of job (copy job, scan to send job, etc.) specified by the user from the image data of the document image specified by the user (step S1). ).

The image output unit 22 acquires the time stamp of the generated image output image data (step S2), and generates a hash value of the image output image data with the time stamp added by a predetermined hash function (step S3).

The image output unit 22 specifies a processing mode corresponding to the hash value of the image output image data to which a time stamp is added, and processes the image output image data in the specified processing mode (step S4). The image data for image output processed in the processing mode may or may not have a time stamp added.

Further, the image output unit 22 stores the original image data for image output and the time stamp thereof in the storage device 14 (step S5).

Then, the image output unit 22 performs image output (printing or transmission of an image data file) based on the image output image data processed in the processing mode corresponding to the above-mentioned hash value (step S6).

In this way, an image output product (print product or image data file) processed in a processing mode corresponding to the hash value can be obtained.

(B) Operation during output image verification

The output document image verification unit 23 verifies the image (output document image) of the image output product obtained as described above (that is, the verification of the image output product).

FIG. 4 describes the operation of the image forming apparatus 1 shown in FIG. 1 at the time of output image verification.

First, the output document image verification unit 23 acquires the output document image (step S11). Next, the output document image verification unit 23 identifies the image output image data and the time stamp stored in the storage device 14 corresponding to the output document image based on the user operation or the like (step S12).

Then, the output document image verification unit 23 reads out the specified image output image data and time stamp, generates a reference image based on the image output image data and time stamp (step S13), and together with the generated reference image. The output document image is verified by comparing it with the output document image (step S14). Then, the output document image verification unit 23 notifies the user of the verification result (whether or not the output document image has been tampered with) by displaying it on the operation panel 13 or transmitting it to a predetermined destination, for example.

As described above, according to the above embodiment, the image output unit 22 generates image data for image output of the document image, acquires a time stamp corresponding to the image data for image output, and sets the time stamp. A hash value of the added image output image data is generated, the image data for image output is processed in a processing mode corresponding to the hash value, and the image data for image output after processing is output (print, image data file). Send, etc.).

This makes it difficult to guess because the processing mode used for image processing is selected by the hash value, and when the output document is tampered with, the tampering is easily detected.

It should be noted that various changes and modifications to the above-described embodiments will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the intent and scope of the subject and without diminishing the intended benefits. That is, such changes and amendments are intended to be included in the claims.

For example, in the above embodiment, the above-mentioned processing mode may include the addition of spots at predetermined positions in a document image. In that case, the inversion corresponding to the above-mentioned hash value is added to a predetermined position (or a position corresponding to the hash value).

The present invention is applicable to, for example, an image forming apparatus such as a multifunction device.

1 Image forming device 11 Printing device 15 Communication device 22 Image output unit 23 Output document image verification unit

Claims (4)

With a printing device
With communication equipment
The image data for image output of the document image is generated, the image is printed by the printing device based on the image data for image output, and the print product is output, or the image data for image output is imaged using the communication device. It is equipped with an image output unit that sends as a data file and executes image output.
The image output unit (a) acquires a time stamp corresponding to the image output image data, (b) generates a hash value of the image output image data to which the time stamp is added, and (c) the said. Processing the image data for image output in a processing mode corresponding to the hash value, and (d) executing the image output for the image data for image output after processing.
An image forming apparatus characterized by. The processing modes include (a) changing the character color of the document image according to a predetermined rule, (b) changing the font size of the document image according to a predetermined rule, and (c) changing the document image according to a predetermined rule. Of changing the font time of (d) inserting a space between characters, a space between lines, or a space between paragraphs of the document image according to a predetermined rule, and (e) reversing the character orientation of the document image according to a predetermined rule. The image forming apparatus according to claim 1, wherein the image forming apparatus is one or a combination of two or more of the above. The image output unit is characterized in that, in the text of the document image, the character position corresponding to the hash value is specified, and the processing of the processing mode is performed on the specified character position. The image forming apparatus according to claim 2. Equipped with an output document image verification unit
The image output unit stores the image data for image output and the time stamp in a predetermined storage device.
The output document image verification unit (a) acquires an output document image based on the print product or the image data file obtained in the image output, and (b) the stored image data for image output and the image data. To generate a reference image as a regular output document image based on the time stamp, and (c) verify the output document image based on the output document image and the reference image.
The image forming apparatus according to any one of claims 1 to 3, wherein the image forming apparatus is characterized.

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