Program, display device, and display method

Abstract

To reduce the amount of data when a plurality of documents are stored.SOLUTION: A program causes a computer to function as: a display processing section that displays a plurality of pages included in a document in a first state on a display section on the basis of original image data, and displays the plurality of pages included in the document in a second state on the display section on the basis of reduced image data of each page; and a data management section that, when a document present in a storage section shifts from the first state to the second state, deletes original image data of the shifted document from the storage section while leaving reduced image data of each page of the shifted document, and when the document present in the storage section shifts from the second state to the first state, acquires the original image data of the shifted document from an external device.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a program, a display device, and a display method. [Background technology]

[0002] Conventionally, there are known techniques for displaying image data of a document. Patent Document 1 discloses a technique in which thumbnail images of each of a plurality of pages included in a document are displayed in the lower part of a display unit, and when one of the thumbnail images is selected, the page corresponding to the selected thumbnail image is identified and the page image of the identified page is displayed in the upper part of the display unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-018734 Summary of the Invention [Problem to be solved by the invention]

[0004] When storing a plurality of documents in a device in order to display the data of the documents, there has been a demand for reducing the amount of data. [Means for solving the problem]

[0005] In view of the above problems, the present invention is a program that causes a computer to function as a display processing unit that displays multiple pages contained in a document in a first state on a display unit based on original image data, and displays multiple pages contained in a document in a second state on the display unit based on reduced image data for each page, and a data management unit that, when a document residing in a memory unit transitions from the first state to the second state, deletes the original image data of the transitioned document from the memory unit while leaving the reduced image data for each page of the transitioned document, and, when a document residing in the memory unit transitions from the second state to the first state, acquires the original image data of the transitioned document from an external device.

[0006] Another aspect of the present invention is a display device comprising: a processor that causes a display unit to display multiple pages included in a document in a first state based on original image data, and causes the display unit to display multiple pages included in a document in a second state based on reduced image data; a communication unit that acquires the original image data of the document that has been transitioned from an external device in response to the document transitioning from the second state to the first state; and a memory unit that stores the original image data of the document in the first state and reduced image data of each page of the document in the second state, but does not store the original image data of the document in the second state, wherein the memory unit stores the original image data of the document that has been transitioned when the document transitions from the second state to the first state, and deletes the original image data of the document that has been transitioned when the document transitions from the first state to the second state.

[0007] Another aspect of the present invention is a display method, which displays multiple pages included in a document in a first state on a display unit based on original image data, and displays multiple pages included in a document in a second state on the display unit based on reduced image data for each page, and when the document transitions from the first state to the second state, deletes the original image data of the transitioned document from a memory unit while leaving the reduced image data for each page of the transitioned document, and when the document transitions from the second state to the first state, stores the original image data of the transitioned document in the memory unit. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram of a display system. [Figure 2] FIG. 1 is a diagram illustrating the configuration of a display device. [Figure 3] FIG. 10 is a diagram showing an example of a display displayed on a display unit. [Figure 4] FIG. 2 is a diagram illustrating an example of the data structure of a document. [Figure 5] 10 is a flowchart showing a display process. [Figure 6] 10 is a flowchart showing detailed processing in an enlarged display process. [Figure 7] FIG. 10 is an explanatory diagram of estimation conditions. [Figure 8] FIG. 10 is a diagram showing a display example of an enlarged display. [Figure 9] FIG. 10 is a diagram showing the data structure of a data set of a document including drawing image data. [Figure 10] FIG. 10 is a diagram showing a display example according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] 1 is a schematic diagram of a display system 1 according to this embodiment. In the display system 1, a user transfers data that the user wishes to view from a user PC 10 owned by the user to a display device 30. The data is transferred via a display management server 20. The user PC 10, display management server 20, and display device 30 are connected via a network.

[0010] The user PC 10 is an information processing device used by the user. The display device 30 is a portable information processing device used by the user. Examples of the display device 30 include a smartphone and a tablet terminal. The display device 30 receives data from the user PC 10 via the display management server 20 and displays the data. The display management server 20 manages the data sent to the display device 30.

[0011] FIG. 2 is a configuration diagram of the display device 30. The display device 30 includes a processor 300, a nonvolatile memory 320, a display unit 330, an operation unit 340, and a communication unit 350. The processor 300 includes a CPU, a ROM, and a RAM, and can execute programs stored in the ROM or nonvolatile memory 320 to control each unit of the display device 30. The processor 300 may be configured as a single chip or multiple chips. Furthermore, for example, an ASIC may be used instead of the CPU, or a configuration in which the CPU and the ASIC work together may be used. The nonvolatile memory 320 stores programs, data, etc. executed by the processor 300.

[0012] The display unit 330 displays various types of information. The operation unit 340 accepts user operations. The operation unit 340 may be integrated with the display unit 330 as a touch panel. The communication unit 350 is one or more antennas that perform wireless communication with an external device. The communication unit 150 may also be a cable connector that performs wired communication with an external device. The antenna and the cable connector are also called communication interfaces.

[0013] As described above, the display device 30 of this embodiment receives data from the display management server 20 and displays it on the display unit 330. However, if the amount of such data becomes large, memory capacity will become insufficient. Therefore, the display device 30 performs processing to reduce the amount of data. As a functional configuration for this purpose, the processor 300 includes a display processing unit 311 and a data management unit 312.

[0014] The functions of the display processing unit 311 and the data management unit 312 are realized by the processor 300 reading and executing programs stored in the nonvolatile memory 320. In other words, hereinafter, the processes described as being executed by the display processing unit 311 and the data management unit 312 are actually processes executed by the processor 300.

[0015] The display processing unit 311 performs processing related to displaying data on the display unit 330. The data management unit 312 performs processing related to data management, such as storing and deleting data to be displayed.

[0016] 3 is a diagram showing an example of a display displayed on the display unit 330 by the display processing unit 311. In this way, the display unit 330 displays a list of multiple documents stored on the display device 30. The documents include text, images, and the like. Each document has multiple pages, and each page is displayed. In this way, the multiple pages of each document are displayed side by side on one screen at the same time.

[0017] More specifically, the first page is displayed in its entirety, and the second page is displayed to the right of the first page as a continuation of the first page. Similarly, the third and subsequent pages are displayed to the right of the previous page. Furthermore, each page is displayed with a partial overlap depending on the total number of pages included in the document. At this time, the later the page, the larger the overlapping area. Also, a reduced version of each page is displayed as a page image while maintaining its shape. For example, assume that the first page of the "DE" document is a portrait-oriented page and the second page is a landscape-oriented page. In this case, as shown in Figure 3, the first page is displayed portrait-oriented and the second page is displayed landscape-oriented. Also, if the number of documents that can be displayed on one screen is, for example, four, and five or more documents are stored, all of the documents are displayed by scrolling.

[0018] FIG. 4 is a diagram showing the data structure of a document displayed on the display unit 330 by the display processing unit 311. One data set 400 corresponding to one document is stored. Identification information is assigned to the data set 400. The data set 400 includes original image data 410 of the document transmitted from the user PC 10, a thumbnail data group 420, and metadata 430. The thumbnail data group 420 includes multiple thumbnail data 421-424 corresponding to each page included in the original image data 410. In the example of FIG. 4, the original image data 410 consists of four pages, and the thumbnail data group 420 includes four thumbnail data 421-424 corresponding to the four pages. The thumbnail data is an example of reduced image data. It is assumed that the thumbnail data group 420 is generated in the display management server 20 based on the original image data 410. As another example, the thumbnail data group 420 may be generated in the user PC 10.

[0019] The metadata 430 is information that indicates the characteristics of a document, and includes, for example, information about the shape of each page, such as the aspect ratio, and the total number of pages. The metadata 430 also includes secondary information related to user operations, such as the page to which a sticky note is attached, the last page opened, the last page viewed (displayed in the default double-page spread position), the page pulled up, and whether the page is read from right to left or left to right. This information can be reflected in the display of the page. For example, sticky note images can be superimposed on pages based on original image data or pages based on thumbnail data in accordance with the metadata. Also, for example, the position of some pages can be shifted and displayed as if they were pulled up in accordance with the metadata.

[0020] The document data set 400 is stored in a document memory provided in, for example, a RAM. Then, the display processing unit 311 displays the document data stored in the document memory on the display unit 330. Here, the document memory is an example of a storage unit.

[0021] FIG. 5 is a flowchart showing the display processing by the display device 30. FIG. 6 is a flowchart showing detailed processing in the enlarged display processing. As shown in FIG. 5, when the data management unit 312 of the display device 30 receives a document (data set) to be displayed from the user PC 10 via the display management server 20 (Y in step S100), it registers the received document in the document memory (step S102). In this way, the data management unit 312 registers the document by storing the original image data and thumbnail data of the document in the storage unit. Note that a similar data set is also registered in the display management server 20.

[0022] Multiple documents can be registered in the document memory. If an unlimited number of documents are registered, the data volume will become so large that it will be impossible to store them all in the document memory. Therefore, in this embodiment, for documents that are likely to be viewed by users, the display device 30 deletes the original image data, which has a relatively large amount of data, from the data contained in the data set, and leaves only the thumbnail data set and metadata. This prevents the data volume in the document memory from becoming too large. Details of this process will be explained with reference to a flowchart. If the data management unit 312 has not received a document (N in S100), the process proceeds to S110.

[0023] After the process of step S102, the data management unit 312 identifies the states of all documents registered in the document memory (step S104). In this embodiment, the document states include a first state and a second state. A document selected by a user is in the first state. In addition, a document that is estimated to have a higher possibility of being selected by a user than a document in the second state is also in the first state. In this embodiment, an estimation condition for the possibility of being selected by a user is set, and if the estimation condition is met, the document is identified as being in the first state, and if the estimation condition is not met, the document is identified as being in the second state. Note that a document selected by a user is configured to satisfy the estimation condition. The estimation condition is, for example, a condition that the document is included in the top eight documents selected alternately from documents recently registered in the document memory and documents recently selected by the user.

[0024] Fig. 7 is an explanatory diagram of the estimation conditions. For example, suppose that 13 documents A to M are registered in the document memory, and the order of most recent registration (registration order) and most recent selection (selection order) are as shown in Fig. 7.

[0025] In this case, the data management unit 312 first selects document A, which is first in the registration order, and then selects document J, which is first in the selection order. Next, document B, which is second in the registration order, is selected. Next, document A, which is second in the selection order, has already been selected, so the third document E, which follows it, is selected. Next, document C, which is third in the registration order, is selected. Next, document C, which is fourth in the selection order, has already been selected, so the fifth document K, which follows it, is selected. Next, document D, which is fourth in the registration order, is selected. Next, document D, which is sixth in the selection order, has already been selected, so the seventh document I, which follows it, is selected. In this way, a total of eight documents are selected, and the state of these documents is identified as the first state. Then, the remaining five documents are identified as the second state.

[0026] Returning to FIG. 5, after the processing of step S104, the data management unit 312 deletes the original image data of each document that has transitioned to the second state (step S106). Documents in the second state are considered less likely to be viewed by users than documents in the first state. Therefore, in this way, the data management unit 312 deletes the original image data of documents in the second state that are less likely to be viewed. Note that even in this case, the data management unit 312 leaves the thumbnails and metadata in the document memory for use when displaying the documents.

[0027] Next, for the document that has transitioned to the first state, the data management unit 312 acquires the original image data from the display management server 20 via the communication unit 350 and registers it in the document memory (step S108). Note that data reception with the display management server 20 may be performed on a data set basis. In this case, the data management unit 312 receives the data set that has transitioned to the first state and updates the target data set to the received data set, i.e., the data set that includes the original image data.

[0028] In this way, when a document in the document memory transitions from the first state to the second state, the data management unit 312 deletes the original image data, leaving behind thumbnail data for each page of the transitioned document. Also, when a document in the document memory transitions from the second state to the first state, the data management unit 312 obtains the original image data of the transitioned document from the display management server 20.

[0029] Next, display processing unit 311 checks whether a document list display instruction has been received in response to a user operation on operation unit 340. If display processing unit 311 has not received a list display instruction (N in step S110), it proceeds to step S100. If display processing unit 311 has received a list display instruction (Y in step S110), it displays a list of all documents stored in the document memory on display unit 330 (step S112). If all documents cannot be displayed on one screen, the list is displayed so that all documents are displayed in response to scrolling.

[0030] At this time, for a document in a first state in which original image data is stored in the document memory, the display processing unit 311 displays each page of the document by rendering an image of each page included in the document based on the original image data. On the other hand, for a data set in a second state in which original image data is not stored in the document memory, the display processing unit 311 displays each page of the document by rendering thumbnail data of each page. As a result, the page displayed based on the thumbnail data has a lower resolution than the page displayed based on the original image data.

[0031] In this way, the display processing unit 311 displays the multiple pages included in the document in the first state on the display unit 330 based on the original image data, and displays the multiple pages included in the document in the second state on the display unit based on the thumbnail data of each page. Since thumbnail data is also stored for the document in the second state, it can be displayed on the display unit 330 together with the document in the first state. This makes it easy for the user to understand the content of the document in the second state as well.

[0032] As another example, the display processing unit 311 may first display each page based on thumbnail data, even for a document whose original image data is stored in the document memory. In this case, the display processing unit 311 then renders the original image data, and when the rendering is complete, changes the image to be displayed from an image based on the thumbnail data to an image based on the original image data. This allows the timing of the start of display to be accelerated.

[0033] Next, if a document is selected in response to a user operation (Y in step S114), display processing unit 311 enlarges and displays the selected document (step S116), and then proceeds to step S100. For example, if the document in the first row shown in Fig. 3 is selected, the document in the first row is enlarged and displayed, as shown in Fig. 8. If a document is not selected (N in step S114), display processing unit 311 proceeds to step S100.

[0034] 6, in the document enlargement process, first, the data management unit 312 checks the state of the selected document. If the selected document is in the second state (Y in step S200), the display processing unit 311 enlarges and displays each page of the selected document based on the thumbnail data of the selected document stored in the document memory (step S202).

[0035] Next, the data management unit 312 transitions the state of the selected document from the second state to the first state (step S204). Specifically, the data management unit 312 updates the states of all documents registered in the document memory in accordance with the estimation conditions described with reference to Fig. 7. As a result, the state of the selected document transitions from the second state to the first state.

[0036] Next, the data management unit 312 obtains the original image data of the selected document from the display management server 20 and registers it in the document memory (step S206). This process is similar to the process in step S108. At this time, if there are documents other than the selected document that have transitioned from the second state to the first state, the data management unit 312 also obtains the original image data of these documents from the display management server 20. Furthermore, if there are documents that have transitioned from the first state to the second state, the data management unit 312 deletes the thumbnail data of these documents from the document memory.

[0037] Next, the display processing unit 311 renders the original image data of the selected document, and when the rendering is complete (Y in step S208), it displays the rendered image as an enlarged view of the document (step S210). In this way, when a document in the second state is selected by the user, the display processing unit 311 displays each page of the document based on the thumbnail data until the original image data of the selected document is acquired from the display management server 20. Then, after acquiring the original image data from the display management server 20, the display processing unit 311 displays each page of the document based on the original image data.

[0038] Furthermore, if the selected document is in the first state (N in step S200), the data management unit 312 enlarges and displays each page of the selected document based on the original image data of the selected document stored in the document memory (step S212).

[0039] Next, a case where a handwritten image is drawn on a document by a user will be described. In this case, handwritten image data representing the handwritten image drawn by the user is generated as an image to be superimposed on the original image, and the handwritten image data is added to the document dataset. FIG. 9 is a diagram showing the data structure of a document dataset including handwritten image data. In addition to original image data 410, dataset 400 includes handwritten image data 510. Furthermore, dataset 400 includes a plurality of handwritten thumbnail data 521-522 corresponding to each page included in handwritten image data 510. Each of handwritten thumbnail data 521-522 is assigned a page number that identifies the corresponding page.

[0040] When the drawing image data is added to the data set, the data set including the drawing image data is transmitted to the display management server 4020. As a result, the drawing image data is also stored in the display management server 4020.

[0041] In this case, in the display process, when the state of the document including the drawing image data transitions from the first state to the second state, the data management unit 312 deletes the drawing image data from the document memory, leaving the drawing thumbnail data. Also, when the state transitions from the second state to the first state, the data management unit 312 acquires the drawing image data from the display management server 20.

[0042] Furthermore, when displaying a document in the first state, the display processing unit 311 displays a drawing added by the user to a page included in the document in the first state by superimposing it on the original image data based on the drawing image data. Furthermore, when displaying a document in the second state, the display processing unit 311 displays a drawing added by the user to a page included in the document in the second state by superimposing it on the thumbnail data based on the drawing thumbnail data.

[0043] Furthermore, the display processing unit 311 prohibits the drawing of a new handwritten image while the handwritten image is being displayed based on the drawing thumbnail data, and enables the drawing of a new handwritten image after the handwritten image is displayed based on the drawing image data.When a new handwritten image is drawn, the data management unit 312 registers the new handwritten image superimposed on the previously drawn handwritten image as new handwritten image data in a data set.In other words, the data management unit 312 updates the handwritten image data.Furthermore, the data management unit 312 also updates the handwritten thumbnail data in accordance with the update of the drawing image data.

[0044] As described above, in the display system 1 of this embodiment, the display device 30 can reduce the amount of data for documents in the second state by deleting the original image data. This allows multiple documents to be stored. Furthermore, when a document in the second state is selected, the display device 30 can obtain the original image data of the selected document and display the document based on the original image data.

[0045] The above-described embodiment is an example for carrying out the present invention, and various other embodiments can be adopted.

[0046] In such a first variant, the inference condition for determining the state of a document may be a condition that classifies a document that is likely to be viewed by a user into the first state, and the specific condition is not limited to the embodiment. For example, the inference condition may be determined according to at least one of the timing of registration in the document memory and the timing of selection by the user, and the specific condition is not limited to the embodiment. As another example, the inference condition may be that the document is included in the five documents most recently selected and the three documents most recently registered.

[0047] As another example, the inferred condition may be a condition such that a document that was displayed on the screen when scrolling was stopped in a list display is preferentially selected as the first state over a document that was not displayed on the screen when scrolling was stopped. Also, the inferred condition may be a condition such that, when a list display is performed by scrolling, a document that was displayed on the screen is preferentially selected as the first state over a document that was not displayed on the screen.

[0048] As a second variation, when deleting the original image data of a document in the second state, the data management unit 312 may leave the original image data of some pages of the document, such as the first page of the document, in the document memory. In this case, when displaying the document in the second state, the display processing unit 311 displays the pages whose original image data is stored in the document memory based on the original image data. Then, the display processing unit 311 displays the pages whose original image data is not stored in the document memory based on thumbnail data. This allows specific pages, such as the first page, which are likely to be viewed by the user, to be displayed at a higher resolution.

[0049] A third modified example will now be described. In this embodiment, the display device 30 receives a document as a data set including thumbnail data. However, it is also possible that only the original image data of the document is acquired, and the data set does not include thumbnail data. In this case, when the document transitions from the first state to the second state, the data management unit 312 generates thumbnail data for each page of the transitioned document and stores this in the document memory. The data management unit 312 then deletes the original image data of the document from the document memory. This makes it possible to similarly manage documents for which thumbnail data has not been acquired with reduced data volume.

[0050] As a fourth modification, in addition to the first and second states, a third state may be managed as the document state. In this case, a first estimation condition defining the first state and a second estimation condition defining the second state are assumed to be set in advance. Here, the first estimation condition is the same as the estimation condition described in the embodiment. The second estimation condition is assumed to be a condition under which a document having the second highest probability of being viewed by a user, after a document in the first state, is classified into the second state. For example, the second estimation condition is a condition under which a document does not satisfy the first estimation condition among the top 30 documents selected alternately from documents recently registered in the document memory and documents recently selected by the user. When a document in the third state is selected by a user, the selected document transitions from the third state to the first state.

[0051] For documents in the third state, the data management unit 312 deletes the original image data and thumbnail data, leaving the metadata. This allows for further reduction in the amount of data in the display device 30. For documents in the third state, the display processing unit 311 then displays multiple pages based on metadata that indicates the characteristics of the multiple pages of the document. Since the metadata includes the shape of each page, blank pages are displayed in the list display in the shape indicated by the metadata. In the example shown in FIG. 10, documents in the third state, i.e., documents corresponding to the metadata, are displayed in the first row.

[0052] When a document in the third state is selected by a user, the display processing unit 311 first enlarges and displays a blank page based on the page shape and number indicated in the metadata of the selected document. The display processing unit 311 then acquires thumbnail data and original image data of the selected document from the display management server 20. Once rendering of the thumbnail data is complete, the display processing unit 311 enlarges and displays the document page based on the thumbnail data, and then once rendering of the original image data is complete, the display processing unit 311 enlarges and displays the document page based on the original image. In this way, even if the document is blank, the page shape and number of pages are displayed, allowing the user to grasp the outline of the document.

[0053] As another example, the display processing unit 311 may display a blank page without displaying based on thumbnail data, and when rendering of the original image data is complete, display an enlarged view of each page based on the original image.

[0054] The above-described embodiment is an example of how the present invention can be implemented, and various other embodiments are possible. For example, various modifications and changes are possible within the scope of the gist of the present invention as defined in the claims, such as applying a modified version of one embodiment to another embodiment.

[0055] Thumbnail data may be image data with a reduced amount of data compared to general original image data. The number of pixels in the thumbnail data may be fixed and fewer than the number of pixels in the original image, or may be dynamically determined based on the screen size of the display device, etc. Thumbnail data may also be image data with a reduced amount of data due to reduced gradation.

[0056] In this application, document selection refers to at least an operation for enlarging and displaying a document, and operations for other purposes may not be included in document selection in this application. For example, if an operation is performed to delete a document in the second state, the operation is not considered to be document selection, and the document may be deleted in the second state without transitioning to the first state.

[0057] Furthermore, the present invention can also be applied as a program or method executed by a computer. It can be realized as a single device as described above, or it can be realized using components included in multiple devices, and it encompasses various aspects. It can also be modified as appropriate, such as being partly software and partly hardware. Furthermore, the invention can also be implemented as a recording medium for a program that controls a system. Of course, the recording medium for the program can be a magnetic recording medium or a semiconductor memory, and any recording medium developed in the future can be considered in exactly the same way. It is also conceivable to apply the present invention as a printer driver or application that executes part or all of the above-described flowchart. [Explanation of symbols]

[0058] 1...display system, 10...user PC, 20...display management server, 30...display device, 300...processor, 311...display processing unit, 312...data management unit, 320...non-volatile memory, 330...display unit, 340...operation unit, 350...communication unit

Claims

1. Computer, a display processing unit that displays a plurality of pages included in the document in the first state on a display unit based on original image data, and displays a plurality of pages included in the document in the second state on the display unit based on reduced image data of each page; a data management unit that, when a document existing in a storage unit is transitioned from the first state to the second state, deletes original image data of the transitioned document from the storage unit while leaving reduced image data of each page of the transitioned document, and, when a document existing in the storage unit is transitioned from the second state to the first state, acquires original image data of the transitioned document from an external device. A program to function as a

2. The program according to claim 1 , wherein the display processing unit displays a plurality of pages included in the document in the first state and a plurality of pages included in the document in the second state side by side.

3. the display processing unit enlarges and displays a document selected by a user; 2. The program of claim 1, wherein when the document in the second state is selected by a user, the selected document transitions from the second state to the first state.

4. The program of claim 3, wherein when a document in the second state is selected by a user, the display processing unit displays the page of the selected document based on reduced image data until the original image data of the selected document is obtained from the external device, and after the original image data of the selected document is obtained from the external device, the program displays the page of the selected document based on the obtained original image data.

5. The program according to claim 1, wherein the data management unit, when a document transitions from the first state to the second state, generates reduced image data of the transitioned document and then deletes the original image data of the transitioned document from the storage unit.

6. The program according to claim 1 , wherein the data management unit registers the document by storing original image data and reduced image data of the document in the storage unit.

7. When deleting the original image data of the document that has transitioned to the second state, the data management unit leaves the original image data of some pages of the document in the storage unit, The program of claim 1, wherein when displaying a document in the second state, the display processing unit displays pages whose original image data is stored in the memory unit based on the original image data, and displays pages whose original image data is not stored in the memory unit based on reduced image data.

8. the display processing unit displays the plurality of pages included in the document in the third state based on metadata indicating characteristics of the plurality of pages included in the document in the third state; 2. The program according to claim 1, wherein the data management unit stores the metadata of the document in the third state in the storage unit, but does not store original image data and reduced image data of the document in the third state in the storage unit.

9. 9. The program of claim 8, wherein when the document in the third state is selected by a user, the selected document transitions from the third state to the first state.

10. The program of claim 8, wherein the display processing unit, when a document in the third state is selected by a user, displays a blank page of the selected document until reduced image data is obtained from the external device, displays a page of the selected document based on the reduced image data after obtaining the reduced image data from the external device, and displays a page of the selected document based on the original image data after obtaining original image data from the external device.

11. 2. The program according to claim 1, wherein the display processing unit displays a page specified by the metadata of the document in the second state on the display unit by superimposing an image indicated by original image data and a sticky note image, and displays a page specified by the metadata of the document in the second state on the display unit by superimposing an image indicated by reduced image data and a sticky note image.

12. The program of claim 1, wherein the display processing unit displays an image indicated by original image data on the display unit at a position shifted from images of other pages for a page specified by metadata of the document in the second state, and displays an image indicated by reduced image data on the display unit at a position shifted from images of other pages for a page specified by metadata of the document in the second state.

13. 2. The program according to claim 1, wherein the display processing unit displays drawings added by the user to pages included in the document in the first state based on drawing image data, and displays drawings added by the user to pages included in the document in the second state based on reduced drawing image data.

14. a processor that displays a plurality of pages included in a document in a first state on a display unit based on original image data, and that displays a plurality of pages included in a document in a second state on the display unit based on reduced image data; a communication unit that acquires original image data of the document that has transitioned from the second state to the first state from an external device in response to the document transitioning from the second state to the first state; a storage unit that stores original image data of the document in the first state and reduced image data of each page of the document in the second state, but does not store the original image data of the document in the second state; Equipped with A display device wherein the storage unit stores the original image data of the document when the document transitions from the second state to the first state, and deletes the reduced image data of the document when the document transitions from the first state to the second state.

15. displaying a plurality of pages included in the document in the first state on a display unit based on the original image data; displaying a plurality of pages included in the document in the second state on the display unit based on reduced image data of each page; When the document is transferred from the first state to the second state, the original image data of the transferred document is deleted from the storage unit while the reduced image data of each page of the transferred document is left; When the document transitions from the second state to the first state, the original image data of the transitioned document is stored in the storage unit.

Images