Display method and display device

Abstract

To reduce the labor of switching a display mode when displaying page images of a document.SOLUTION: A display method includes: a detection step of causing a display device 1 to detect a display size when multiple page images PG are displayed in a document display area 201 arranged on a display screen 141; and a selection step of selecting a display mode in the document display area 201. The detection step includes detecting a difference length BD. The selection step includes causing to select, when the difference length BD is equal to or greater than a display setting value, a multiple page display mode for displaying a plurality of page images PG side by side, or when the difference length BD is less than the display setting value, a single page display mode for displaying one of the page images PG.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] Conventionally, there is known a technology for displaying document pages on a display device such as a smartphone. The display device described in Patent Document 1 displays thumbnail images of each page of an electronic book or an electronic photograph. In addition, in response to a user's operation to select a thumbnail image, two pages of images of the page corresponding to the selected thumbnail image are displayed side by side. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-71500 A Summary of the Invention [Problem to be solved by the invention]

[0004] As described in Patent Document 1, a display mode in which images of multiple pages are displayed side by side is useful because it allows a large amount of information to be viewed simultaneously. It is also conceivable to display an image of a single page as a display mode for displaying document pages. This display mode has the advantage of displaying the page large. Thus, there are multiple document display modes, each with its own advantages, but switching between these display modes requires time and effort. Therefore, there is a need to reduce the time and effort required to switch between display modes. [Means for solving the problem]

[0005] One aspect of the present invention for solving the above problem is a display method for displaying a document on a display device having a display screen, the display method including: a detection step for detecting a display size when multiple page images, which are images of pages that make up the document, are displayed in a document display area arranged on the display screen; and a selection step for selecting a display mode in the document display area based on the detection result of the detection step; in the detection step, a differential length, which is the difference in the direction along a first axis of the document display area between the length of an entire image formed by arranging multiple page images, and the length of the document display area, is detected; and in the selection step, if the differential length is equal to or greater than a display setting value, a multiple page display mode is selected in which multiple page images are displayed side by side; and if the differential length is smaller than the display setting value, a single page display mode is selected in which one page image is displayed.

[0006] Another aspect for solving the above problem is a display device comprising: a display unit having a display screen; a detection unit that detects a display size when multiple page images, which are images of pages that make up a document, are displayed in a document display area arranged on the display screen; a selection unit that selects a display mode in the document display area based on the detection result of the detection unit; and a display control unit that causes the display unit to display the page images in the document display area in the display mode selected by the selection unit, wherein the detection unit detects a differential length, which is the difference in the direction along a first axis of the document display area, between the length of an entire image formed by arranging multiple page images side by side, and the length of the document display area, and the selection unit selects a multiple page display mode in which multiple page images are displayed side by side if the differential length is equal to or greater than a display setting value, and selects a single page display mode in which one page image is displayed if the differential length is smaller than the display setting value. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating the configuration of a printing system according to an embodiment. [Figure 2] FIG. 10 is a screen diagram showing an example of a preview screen when a one-page display mode is executed. [Figure 3] FIG. 10 is a screen diagram showing an example of a preview screen when a two-page display mode is executed. [Figure 4] FIG. 10 is a screen diagram showing an example of a preview screen when a two-page display mode is executed. [Figure 5] 10 is a flowchart showing the processing of a control unit of the smartphone. [Figure 6] 10 is a flowchart showing the processing of a control unit of the smartphone. [Figure 7] 10 is a flowchart showing the processing of a control unit of the smartphone. [Figure 8] FIG. 10 is a screen diagram showing an example of a preview screen when a two-page display mode is executed. [Figure 9] FIG. 10 is an external view of a display device as another application example. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, this embodiment will be described with reference to the drawings.

[0009] A printing system 100 according to this embodiment will be described. FIG. 1 is a diagram illustrating an example of the configuration of a printing system 100 and a smartphone 1. As shown in FIG.

[0010] The printing system 100 includes a smartphone 1 and a printer 2. The smartphone 1 and printer 2 are connected to each other so that they can communicate with each other via short-range wireless communication, such as Bluetooth (registered trademark) or NFC (Near Field Communication). The smartphone 1 and printer 2 are also connected to each other so that they can communicate with each other via wireless communication, such as Wi-Fi (registered trademark). Wireless communication using Wi-Fi allows for faster communication than short-range wireless communication such as NFC.

[0011] The smartphone 1 selects a print target based on a user operation and transmits print instruction information CM instructing the printer 2 to print the selected print target. The smartphone 1 may transmit the print instruction information CM directly to the printer 2, or may transmit it to the printer 2 via a server device or the like. The printer 2 prints the print target on a print medium such as printing paper based on the print instruction information CM from the smartphone 1.

[0012] The smartphone 1 is communicably connected to a personal computer or a server device (not shown) via wireless communication such as Wi-Fi, etc. The smartphone 1 acquires document information DC from the personal computer or the server device.

[0013] The smartphone 1 includes a control unit 11, a touch panel 14, a position sensor 15, and a communication interface 16. The control unit 11 controls each unit of the smartphone 1. The touch panel 14 receives operations from a user and displays various images. The touch panel includes a display 141 such as an LCD (Liquid Crystal Display) and a touch sensor 142.

[0014] The display 141 displays various images in accordance with instructions from the control unit 11. The touch sensor 142 is formed integrally with the display surface of the display 141 and receives touch operations from the user. The touch sensor 142 is configured, for example, with a capacitance sensor or a pressure-sensitive sensor. A touch operation is an operation in which a user brings a pointer, such as a finger or a touch input pen, into contact with the surface of the display 141. When a touch operation is performed, the touch sensor 142 generates an operation signal including the contact position. The touch sensor 142 outputs the operation signal to the control unit 11. The touch sensor 142 may be configured to detect a multi-touch operation in which multiple positions on the touch sensor 142 are touched simultaneously. The display 141 corresponds to an example of a "display screen." The touch sensor 142 can be called an "input unit." The touch panel 14 corresponds to an example of a "display unit."

[0015] Examples of user operations on the touch sensor 142 include a touch operation in which an indicator touches the surface of the display 141, as well as a long touch operation, a swipe operation, and a pinch operation. A long touch operation is an operation in which an indicator that has been touched to the display 141 is maintained in contact with the touch sensor 142 for a predetermined period of time or longer without being removed. A swipe operation is also called a flick operation. A swipe operation is an operation in which an indicator is brought into contact with the display 141 and moved while maintaining contact. A pinch operation is an operation in which multiple indicators are brought into contact with the touch sensor 142 and the distance between the indicators is changed while the indicators are kept in contact with the touch sensor 142. The touch sensor 142 may be configured to determine the type of operation and output an operation signal indicating the type of operation to the control unit 11. Alternatively, the touch sensor 142 may be configured to generate an operation signal indicating the contact position at a preset sampling period. In this case, the control unit 11 may be configured to determine the type of operation performed by the user based on the operation signal input from the touch sensor 142.

[0016] The attitude sensor 15 is a sensor that detects the attitude of the smartphone 1. The attitude sensor 15 is configured by an acceleration sensor, a gyro sensor, a magnetic sensor, or a combination of these. These sensors may be triaxial sensors. The attitude sensor 15 may also be a sensor unit that integrates multiple sensors. Specifically, the attitude sensor 15 may be an inertial measurement unit (IMU) that has a triaxial acceleration sensor and a triaxial gyro sensor.

[0017] The communication interface 16 includes a wireless communication interface circuit including an antenna, an RF (Radio Frequency) circuit, an encoder, a decoder, and the like. The communication interface 16 communicates with the printer 2 via short-range wireless communication such as Bluetooth or NFC in accordance with instructions from the control unit 11. The communication interface 16 communicates with a server device (not shown) and the printer 2 via wireless communication such as Wi-Fi. The smartphone 1 corresponds to an example of a "display device."

[0018] In this embodiment, the communication interface 16 communicates with the printer 2 via short-range wireless communication such as Bluetooth or NFC, but is not limited to this. The communication interface 16 may also communicate with the printer 2 via other wireless communication such as Wi-Fi. The communication interface 16 may also communicate with the printer 2 via a wired connection in accordance with the Ethernet (registered trademark) standard or the like.

[0019] The control unit 11 is a controller including a processor 12 and a memory 13 . The memory 13 is a storage device that non-volatilely stores programs and data executed by the processor 12. The memory 13 is configured by a magnetic storage device such as a hard disk drive (HDD), a semiconductor storage device such as a solid state drive (SSD), a semiconductor storage element such as a flash read only memory (ROM), or other types of non-volatile storage devices. The memory 13 may include a random access memory (RAM) that configures the work area of ​​the processor 12. The memory 13 stores data processed by the control unit 11 and programs executed by the processor 12.

[0020] The memory 13 stores an OS (operating system) 131 and an APP (application program) 132 as programs executed by the processor 12. The OS 131 is a control program that realizes the basic functions of the smartphone 1 and provides a platform for the APP 132. The OS 131 is, for example, Android (registered trademark) OS, Windows (registered trademark) OS, or iOS (registered trademark), but may be another OS.

[0021] APP132 is a program that realizes a specific function of the smartphone 1. In this embodiment, APP132 has a function of displaying an image based on document data. When the smartphone 1 is powered on, it loads and executes OS131 and transitions to a state in which APP132 can be executed. The smartphone 1 starts APP132 in accordance with a user operation or the like. Here, the smartphone 1 may be configured to be able to execute multiple application programs, not just APP132. In other words, the memory 13 may be configured to store multiple application programs, but a description of such a configuration will be omitted.

[0022] The memory 13 stores setting values ​​135. The setting values ​​135 include reference values ​​and setting values ​​that are referenced in the processing executed by the processor 12.

[0023] The processor 12 may be configured as a single processor, or may be configured such that multiple processors function as the processor 12. The processor 12 executes programs stored in the memory 13 to control each part of the smartphone 1.

[0024] In this embodiment, the processor 12 controls each part of the smartphone 1 by executing the OS 131 and the APP 132, but the control unit 11 may be an ASIC (Application Specific Integrated Circuit). The ASIC may execute processing based on implemented functions. The control unit 11 may be a signal processing circuit. The signal processing circuit may execute processing by performing signal processing.

[0025] The control unit 11 includes, as functional blocks, a display control unit 121, a detection unit 122, a selection unit 123, and a reception unit 124.

[0026] When the processor 12 executes the APP 132, the processor 12 functions as a display control unit 121, a detection unit 122, a selection unit 123, and a reception unit 124. When the processor 12 executes the APP 132, the processor 12 causes the memory 13 to function as a document information storage unit 133 and an image information storage unit 134.

[0027] The document information storage unit 133 stores document information DC. The document information DC is data in a document format such as PDF (Portable Document Format) or JPEG (Joint Photographic Experts Group). The document information storage unit 133 stores at least one piece of document information DC for one document. The document information DC includes various information about the page numbers, order, size, and shape of the pages that make up the document. The document information storage unit 133 may be capable of storing multiple pieces of document information DC. The smartphone 1, for example, obtains the document information DC from a personal computer or a server device via the communication interface 16 and stores it in the document information storage unit 133.

[0028] The image information storage unit 134 stores various images and screens to be displayed on the display 141. The image information storage unit 134 stores a print image PP, a thumbnail image PS, and a button image BT. The print image PP constitutes a page image PG to be displayed on the display 141. That is, the smartphone 1 displays the page image PG based on the print image PP. The thumbnail image PS and the button image BT constitute a preview screen 200. The button image BT is an image for operation to switch the display mode, which will be described later, by a user performing a touch operation. The page image PG, the thumbnail image PS, and the button image BT will be further described with reference to FIG. 2.

[0029] The display control unit 121 controls the display 141 to display a screen including information about the operating state of the smartphone 1 and the execution of the APP 132 on the display 141. For example, the display control unit 121 generates display data for displaying a preview screen 200. The display control unit 121 outputs the display data to the display 141, thereby causing the display 141 to display the preview screen 200.

[0030] The preview screen 200 is a screen that allows the user to visually check the state of the printed matter that the smartphone 1 will cause the printer 2 to print before printing. The preview screen 200 is displayed when the APP 132 is started by a user operation. Therefore, even if the user does not want the printer 2 to execute printing, the user can display the preview screen 200 for the purpose of viewing the document. For this reason, the preview screen 200 can be called a viewing screen intended for viewing the document.

[0031] The detection unit 122 detects the display size of a document to be displayed when it is displayed on the preview screen 200. The document to be displayed is selected from documents stored in the document information storage unit 133. For example, when the APP 132 is started, the document that was displayed when the APP 132 was last started may be selected as the document to be displayed. Alternatively, the document to be displayed may be selected in accordance with a user operation after the APP 132 is started. The detection unit 122 detects the display size when page images PG of pages constituting the document to be displayed are displayed on the preview screen 200. Details of the detection performed by the detection unit 122 will be described later.

[0032] The selection unit 123 selects the display mode of the preview screen 200. The display mode of the preview screen 200 is selected from one of a one-page display mode in which a page image PG of one page is displayed, and a multi-page display mode in which a plurality of page images PG are displayed side by side on the preview screen 200. In this embodiment, a two-page display mode will be described as an example of the multi-page display mode. The two-page display mode is a display mode in which two page images PG are displayed side by side on the preview screen 200. When the two-page display mode is executed, the contents of two pages of the document are displayed side by side on the preview screen 200.

[0033] The reception unit 124 receives operations on the smartphone 1 performed by the user. The reception unit 124 receives operations performed by the user based on operation signals input from the touch sensor 142. The reception unit 124 has a function of receiving at least a touch operation. The reception unit 124 may have a function of identifying, for example, the above-mentioned long touch operation, swipe operation, and pinch operation. The reception unit 124 identifies the content of the operation performed by the user based on the operation position on the display 141. For example, the reception unit 124 identifies an operation on a button image BT, an operation on a thumbnail image PS, etc.

[0034] FIG. 2 is a screen diagram showing an example of a preview screen 200 when the one-page display mode is executed. 2 shows the main body 10 of the smartphone 1. The smartphone 1 has a display 141 disposed on the front surface of the main body 10. Of the portion of the display 141 exposed on the front surface of the main body 10, almost the entire portion is the display area of ​​the display 141.

[0035] The preview screen 200 includes a document display area 201 and a thumbnail display area 202. FIG. 2 and FIGS. 3, 4, and 8, which will be described later, show examples in which the preview screen 200 is displayed over the entire display area of ​​the display 141, but the preview screen 200 may be displayed over only a portion of the display area of ​​the display 141. These figures show examples in which the document display area 201 is arranged at the top of the preview screen 200 and the thumbnail display area 202 is arranged at the bottom of the preview screen 200, so that the document display area 201 and the thumbnail display area 202 do not overlap each other. Note that in each figure, a gap is shown between the document display area 201 and the thumbnail display area 202, but this is a modification to make the figures easier to understand. The document display area 201 and the thumbnail display area 202 may also be arranged without a gap on the preview screen 200. Furthermore, the display area of ​​the display 141 and the preview screen 200 may completely coincide with each other.

[0036] 2, and FIGS. 3, 4, and 8, which will be described later, illustrate an X-axis and a Y-axis as directional references on the preview screen 200. The X-axis is an axis parallel to the horizontal direction of the preview screen 200. The Y-axis is an axis perpendicular to the X-axis and parallel to the vertical direction of the preview screen 200. The X-axis corresponds to an example of the first axis, and the Y-axis corresponds to an example of the second axis.

[0037] Also shown in the figure are directions R and L along the X-axis direction. Direction R corresponds to the right direction on the preview screen 200. Direction L corresponds to the left direction on the preview screen 200. Similarly, directions UP and DW along the Y-axis are shown in the figure. Direction UP corresponds to the upward direction on the preview screen 200. Direction DW corresponds to the downward direction on the preview screen 200. In the following explanation, these directions will be referred to as right direction R, left direction L, upward direction UP, and downward direction DW.

[0038] In each figure, the size of the document display area 201 in the direction along the X axis is referred to as the display area width WD, and the size of the document display area 201 in the direction along the Y axis is referred to as the display area height LD. The display area width WD can be called the horizontal size of the document display area 201, and the display area height LD can be called the vertical size of the document display area 201.

[0039] A page image PG is arranged in the document display area 201. The page image PG is an image of a page that constitutes a document, and is an image generated from the print image PP as described above.

[0040] In the one-page display mode, one page image PG is positioned at the center of the document display area 201. The display control unit 121 adjusts the display size of the page image PG to match the size of the document display area 201. In a typical example, the size of the page image PG is enlarged so that it is maximized within a range in which the size of the page image PG in the direction along the X-axis is equal to or less than the display area width WD and the size of the page image PG in the direction along the Y-axis is equal to or less than the display area height LD. Here, the display control unit 121 performs enlargement while maintaining the aspect ratio of the page image PG. Therefore, if the page image PG is a portrait-oriented image that is long in the up-down direction, the page image PG is displayed so that the size of the page image PG in the direction along the Y-axis matches the display area height LD, as shown in FIG. 2. In contrast, if the page image PG is a landscape-oriented image that is long in the left-right direction, the page image PG is displayed so that the size of the page image PG in the direction along the X-axis matches the display area width WD.

[0041] 2, in the document display area 201, margin areas B are generated in the left direction L and right direction R of the page image PG. The margin area B located in the left direction L of the page image PG is referred to as margin area B1, and the margin area B located in the right direction R of the page image PG is referred to as margin area B2. When there is no need to distinguish between margin areas B1 and B2, they are referred to as margin areas B. The sizes of margin areas B1 and B2 in the direction along the X axis are referred to as margin sizes BD1 and BD2, respectively.

[0042] The thumbnail display area 202 displays a thumbnail image group SG, including thumbnail images PS of each page included in the document to be displayed. The thumbnail image group SG includes thumbnail images PS corresponding to at least some of the pages included in the document to be displayed, and may include thumbnail images PS of all pages. In the thumbnail display area 202, the thumbnail images PS are tilted to show the contents of the document pages. In the center of the thumbnail display area 202 along the X axis, the thumbnail image PS is enlarged to an extent that its contents can be discerned, and multiple thumbnail images PS are displayed overlapping each other at both ends. The display control unit 121 moves the thumbnail image PS in the thumbnail display area 202 in response to a user operation. When the receiving unit 124 receives a swipe operation to move the thumbnail image PS in the left direction L or the right direction R, the display control unit 121 moves the thumbnail image PS in the direction of the swipe operation. This allows the user to move the thumbnail image PS of the desired page to the center of the thumbnail display area 202.

[0043] When the receiving unit 124 receives an operation to select one of the thumbnail images PS in the thumbnail display area 202, the display control unit 121 identifies the page corresponding to the touched thumbnail image PS. The display control unit 121 displays the page image PG of the identified page in the document display area 201. This operation is, for example, a touch operation on one of the thumbnail images PS or an operation of swiping the thumbnail image PS in the upward direction (UP).

[0044] In this way, with the preview screen 200 displayed, the user can select a page of the document while looking at the thumbnail image PS in the thumbnail display area 202, and the page image PG of the selected page is displayed enlarged in the document display area 201.

[0045] A button image BT is displayed on the preview screen 200. The button image BT is arranged in the document display area 201. The button image BT is a so-called floating button. Therefore, the display control unit 121 can arrange the button image BT either in a position where it overlaps the page image PG or in a position where it does not overlap the page image PG. For example, the display control unit 121 moves the display position of the button image BT in accordance with a flick operation by the user. The button image BT corresponds to an example of a "switch button."

[0046] The button image BT is a button for instructing switching of the display mode of the preview screen 200, and when the accepting unit 124 accepts a touch operation on the button image BT, the display control unit 121 switches between the one-page display mode and the two-page display mode.

[0047] FIG. 3 is a screen diagram showing an example of a preview screen 200 when the two-page display mode is executed. In FIG. 3, two page images PG are designated page images PG1 and PG2. Page images PG1 and PG2 are images of different pages. For example, page image PG2 is an image of a page adjacent to page image PG1 in a document to be displayed. When there is no need to distinguish between them, they are referred to as page images PG. Page images PG1 and PG2 are collectively referred to as an entire image TG. The size of the entire image TG in the direction along the X-axis is referred to as an entire image width WP. In the entire image TG, page images PG1 and PG2 do not overlap each other but are arranged side by side with no gaps. The arrangement direction of page images PG1 and PG2 is determined based on document information DC. More specifically, the display control unit 121 determines the arrangement direction of page images PG1 and PG2 according to the arrangement of pages in the document to be displayed. For example, if the document to be displayed is a document in which pages are arranged horizontally, page images PG1 and PG2 are arranged horizontally.

[0048] 3, the size of the entire image TG in the direction along the Y axis is the same as the display area height LD. In other words, the entire image TG is enlarged to its maximum in the document display area 201. In this example, because the page images PG1 and PG2 are images of vertically long pages, a margin area B1 is generated to the left of the entire image TG in the direction L, and a margin area B2 is generated to the right of the entire image TG in the direction R.

[0049] The display control unit 121 may enlarge the entire image TG larger than the state shown in FIG. 3. In this case, the display control unit 121 can enlarge the entire image TG to a degree that the main text MC of the page images PG1 and PG2 does not protrude beyond the display area width WD of the document display area 201. The main text MC is the characters and images contained in the document to be displayed. In the page images PG1 and PG2, the area outside the main text MC indicates the margins contained in the document pages. The display control unit 121 enlarges the entire image TG so that the size of the main text MC is equal to or smaller than the display area height LD and the display area width WD. The margins of the page images PG1 and PG2 that protrude beyond the document display area 201 are not displayed.

[0050] FIG. 4 is a screen diagram showing an example of a preview screen 200 when the two-page display mode is executed, and particularly shows an example in which the pages included in the document to be displayed are landscape-oriented. In the example of Figure 4, page images PG1 and PG2 are images of landscape-oriented pages. Therefore, the overall image TG is elongated in the left-right direction as a whole. By enlarging the overall image TG to fit the size of the document display area 201, the overall image width WP matches the display area width WD, and the vertical size of the overall image TG is smaller than the display area height LD.

[0051] As shown in Figures 2 and 3, when a document to be displayed includes portrait-oriented pages, the display size of page image PG in single-page display mode and the display size of page image PG1 in two-page display mode do not change significantly. The same is true for page image PG2. Therefore, whether in single-page display mode or two-page display mode, the user can clearly view the contents of page image PG. Furthermore, the two-page display mode shown in Figure 3 is convenient because it allows the user to simultaneously view the contents of multiple page images PG1 and PG2. Therefore, when displaying the document illustrated in Figures 2 and 3, the two-page display mode is suitable.

[0052] In contrast, as shown in Figure 4, when the document to be displayed contains landscape pages, the single-page display mode allows page image PG1 to be displayed at a larger magnification than the two-page display mode. The same is true for page image PG2. Therefore, the single-page display mode is preferable when displaying the document shown in Figure 4.

[0053] When the smartphone 1 executes the APP 132 to display the preview screen 200, the smartphone 1 has a function of selecting a one-page display mode or a two-page display mode as the display mode of the preview screen 200 according to the document to be displayed. When this function is executed, the detection unit 122 detects the margin size BD when the two-page display mode is executed.

[0054] For example, when displaying the document illustrated in Fig. 3, the detection unit 122 detects the sizes of the margins BD1 and BD2. The detection unit 122 determines the display size of the entire image TG based on the aspect ratio of the print image PP and the display area width WD and display area height LD of the document display area 201.

[0055] In this case, as described above, the detection unit 122 determines the display size of the entire image TG so that the vertical size of the entire image TG is equal to the display area height LD. Therefore, the display size of the entire image TG in the direction along the Y axis of the display 141 is equal to the display area height LD. The entire image width WP may exceed the display area width WD. In other words, this includes a state in which the entire image TG extends beyond the left and right sides of the document display area 201.

[0056] The detection unit 122 detects the margin size BD, which is the difference between the overall image width WP and the display area width WD, by subtracting the overall image width WP from the display area width WD, as shown in the following equation (1). The margin size BD is the sum of the margin size BD1 and the margin size BD2. In the example described here, the margin size BD may be a negative value. BD=WD-WP (1)

[0057] The selection unit 123 compares the value of the margin size BD calculated by the detection unit 122 with a preset value. This value is set as the display setting value. The display setting value is included in the setting value 135 and stored in the memory 13. The value of the margin size BD and the display setting value are values ​​in units of, for example, one dot or one pixel of the display resolution of the display 141. The value of the margin size BD and the display setting value may be values ​​obtained by converting the display size into millimeters.

[0058] The selection unit 123 selects the two-page display mode when the margin size BD is equal to or greater than the display setting value. The selection unit 123 selects the one-page display mode when the margin size BD is smaller than the display setting value. The display setting value may be zero. In this case, the selection unit 123 selects the two-page display mode when the entire image width WP matches the display area width WD.

[0059] The display setting value may be a negative value. In this case, in the two-page display mode, the entire image TG is displayed in the document display area 201 with part of the entire image TG extending beyond the document display area 201. In this case, it is preferable that the display setting value is a value that prevents the main text MC of the page images PG1 and PG2 from extending beyond the document display area 201.

[0060] If the margin size BD is equal to or greater than the display setting value, the display size of the page images PG1 and PG2 in the two-page display mode is the same as or similar to that in the one-page display mode. In this case, the visibility of the contents of the page images PG1 and PG2 in the two-page display mode is not inferior to that in the one-page display mode. Therefore, it is preferable to display in the two-page display mode.

[0061] In the above process, the detection unit 122 may detect the size of the margins based on the body text MC of the page images PG1 and PG2. That is, the detection unit 122 may calculate a content margin width ND instead of the margin size BD. The content margin width ND is the difference between the width of the main text MC included in the entire image TG and the display area width WD. The width of the main text MC is the size of the area including the main text MC in the entire image TG in the direction along the X axis, and is the main text width WMC shown in the figure. The size of the main text MC and the main text width WMC are included in the document information DC, for example, as a ratio to the page size.

[0062] The detection unit 122 determines the display size of the entire image TG so that the vertical size of the main text MC is equal to the display area height LD. In other words, the detection unit 122 determines the display size of the entire image TG so that the main text MC is expanded vertically to fill the entire document display area 201. Therefore, the display size of the main text MC in the direction along the Y axis of the display 141 is equal to the display area height LD.

[0063] The detection unit 122 detects the content margin width ND by subtracting the body width WMC from the display area width WD, as shown in the following formula (2). The content margin width ND is the sum of the content margin width ND1 in the left direction L of the body MC and the content margin width ND2 in the right direction R of the body MC. The selection unit 123 compares the content margin width ND with the display setting value, and selects the two-page display mode if the content margin width ND is equal to or greater than the display setting value. When the detection unit 122 detects the content margin width ND, the display setting value is set so as not to include negative values. In other words, the display setting value is a value that belongs to a range that includes 0 and positive values. ND=WD-WMC (2)

[0064] 5, 6, and 7 are flowcharts showing the processing of the control unit 11 of the smartphone 1. Fig. 6 and Fig. 7 show a part of the processing shown in Fig. 5 in detail. In step S1, the control unit 11 loads the APP 132 in accordance with a user's operation and starts the APP 132.

[0065] In step S2, the control unit 11 executes a detection process using the detection unit 122. Details of the detection process executed in step S2 are shown in FIG.

[0066] In step S21, the detection unit 122 identifies the size of the document display area 201. Specifically, the detection unit 122 identifies the display area width WD and the display area height LD. In step S22, the detection unit 122 identifies the shape of a page included in the document to be displayed. The page shape is, specifically, the aspect ratio of the page, which is the ratio between the length of the page in the direction along the X axis and the length of the page in the direction along the Y axis. The page shape may be whether the page is vertically or horizontally oriented. Furthermore, in step S22, the detection unit 122 may identify a standard size and orientation of the page. For example, the detection unit 122 identifies that the page is a standard A6 size, portrait orientation. The page shape defines the shape of the page image PG.

[0067] In step S22, if the document to be displayed contains a mixture of pages with different shapes, the detection unit 122 identifies the shape of any of the pages. In a first method, the detection unit 122 identifies the shape of the page located at the beginning of a document and sets the identified shape of the page as the shape of the page of the document to be displayed. The document to be displayed has a configuration in which multiple pages are arranged in order. According to the first method, the detection unit 122 can identify the shape of the page of the document to be displayed by identifying the shape of the first page, without determining the shapes of the pages from the second page onwards.

[0068] As a second method, the detection unit 122 may identify the shapes of all pages of the document to be displayed, and use the shape that corresponds to the most pages as the shape of the page of the document to be displayed. According to the second method, processing is performed according to the shapes of the most pages among the pages included in the document to be displayed. In other words, processing is performed according to the shapes that occupy a large proportion of the document to be displayed.

[0069] In step S23, the detection unit 122 calculates the aspect ratio of the entire image TG when the page image PG having the shape identified in step S22 is displayed in the two-page display mode. In step S24, the detection unit 122 calculates the size of the entire image TG based on the display area width WD, the display area height LD, and the aspect ratio of the entire image TG calculated in step S23. When the detection unit 122 performs processing based on the entire image TG, the size of the entire image TG calculated in step S24 is the entire image width WP. When the detection unit 122 performs processing based on the main text MC, the size of the entire image TG calculated in step S24 is the main text width WMC.

[0070] In step S25, the detection unit 122 performs the process shown in the above formula (1) or formula (2) to calculate the difference length. The difference length is the margin size BD or the content margin width ND.

[0071] 5, in step S3, the control unit 11 executes a selection process using the selection unit 123. Details of the selection process executed in step S3 are shown in FIG.

[0072] In step S31, the selection unit 123 compares the difference length calculated in step S25 with the display setting value. In step S32, the selection unit 123 determines whether the difference length is equal to or greater than the display setting value.

[0073] If the selection unit 123 determines that the difference length is equal to or greater than the display setting value (step S32; YES), the process proceeds to step S33, where the two-page display mode is selected. If the selection unit 123 determines that the difference length is not equal to or greater than the display setting value (step S32; NO), that is, if the selection unit 123 determines that the difference length is smaller than the display setting value, the process proceeds to step S34, where the one-page display mode is selected.

[0074] Returning to FIG. 5, in step S4, the control unit 11 causes the display control unit 121 to display the preview screen 200 in accordance with the display mode selected by the selection unit 123.

[0075] By the processing of steps S1 to S4, the display mode of the page image PG displayed on the display 141 when the APP 132 is started is automatically selected from the one-page display mode and the two-page display mode.

[0076] In step S5, the control unit 11 determines whether the display control unit 121 has changed the display area of ​​the preview screen 200 or not. There are several examples of cases in which the display area of ​​the preview screen 200 is changed. The first example is when the user starts executing an application program different from the APP 132, causing the OS 131 to change the shape or size of the display area used by the APP 132. The first example is triggered by the user operating the smartphone 1 to instruct execution of an application program, or by the start of an application program that has been scheduled for execution.

[0077] The second example is when the control unit 11 detects a change in the attitude of the main body 10 using the attitude sensor 15, and the function of the OS 131 changes the display size of the preview screen 200 to match the attitude of the main body 10. The second example occurs, for example, when the main body 10 is rotated in the direction indicated by the symbol R in FIG. 2.

[0078] If it is determined that the display area has been changed (step S5; YES), the control unit 11 returns to step S2.

[0079] If it is determined that the display area has not been changed (step S5; NO), the control unit 11 proceeds to step S6. In step S6, the control unit 11 determines whether or not the button image BT has been operated by the reception unit 124. If it is determined that the button image BT has been operated (step S6; YES), the control unit 11 proceeds to step S7.

[0080] In step S7, the control unit 11 selects a display mode different from the currently selected display mode by the selection unit 123. For example, if the button image BT is operated while displaying in the one-page display mode, the selection unit 123 selects the two-page display mode in step S7.

[0081] In step S8, the control unit 11 causes the display control unit 121 to update the display of the preview screen 200 in the display mode selected in step S7. Thereafter, the control unit 11 returns to step S5.

[0082] In step S6, if it is determined that the button image BT has not been operated (step S6; NO), the control unit 11 proceeds to step S9. In step S9, the control unit 11 determines whether or not an operation to select a thumbnail image PS has been performed in the thumbnail display area 202 by the reception unit 124.

[0083] If it is determined that a user operation to select a thumbnail image PS has been performed (step S9; YES), the control unit 11 proceeds to step S10. In step S10, the control unit 11 identifies a page image PG corresponding to the thumbnail image PS selected by the user operation. In step S11, the control unit 11 causes the display control unit 121 to display the page image PG identified in step S10 on the preview screen 200 in one-page display mode. Thereafter, the control unit 11 returns to step S5.

[0084] If it is determined that the user has not performed an operation to select a thumbnail image PS (step S9; NO), the control unit 11 proceeds to step S12. In step S12, the control unit 11 determines whether or not to end the display of the preview screen 200. If it is determined not to end the display (step S12; NO), the control unit 11 returns to step S5. If it is determined to end the display (step S12; YES), the control unit 11 ends the display of the preview screen 200 and stops the execution of the APP 132.

[0085] In the above process, step S2 corresponds to an example of a "detection step," step S3 corresponds to an example of a "selection step," step S4 corresponds to an example of a "display step," and step S11 corresponds to an example of a "selection page display step."

[0086] In the above process, a display mode may be selected based on the result of determining the shape of the pages included in the document to be displayed in step S22. For example, if the shape of the first page among the pages constituting the document is landscape in step S22, steps S23-S25 may not be executed, and the single-page display mode may be selected in step S3. Also, for example, if the proportion of portrait-oriented pages among all pages constituting the document is less than a determination criterion, steps S23-S25 may not be executed, and the single-page display mode may be selected in step S3.

[0087] In these cases, the display mode can be determined without executing steps S23-S25. When the page shape of the document to be displayed is landscape, this means that the width of the page is longer than the height of the page. In this case, the difference length calculated in steps S23-S25 is likely to be smaller than the display setting value. Therefore, there is an advantage that the display mode can be appropriately selected with less processing.

[0088] In the above configuration, when the page image PG is displayed in the two-page display mode, the document display area 201 may be enlarged. Fig. 8 is a screen diagram showing yet another example of the two-page display mode.

[0089] In the example shown in FIG. 8, the display area height LD is enlarged by a length AD compared to the example shown in FIG. 3. For example, when starting display in two-page display mode in step S4, the display control unit 121 enlarges the document display area 201 as shown in FIG. 8. This improves the visibility of the page image PG when executing the two-page display mode. In the two-page display mode, the overall image width WP or the body width WMC is often smaller than the display area width WD. Therefore, by enlarging the display area height LD, the overall image width WP and the body width WMC can be enlarged, and the overall image TG can be enlarged. In this case, when displaying the page image PG in one-page display mode, the display control unit 121 does not enlarge the document display area 201, but instead sets the document display area 201 to its initial size, as shown in, for example, FIG. 2 or FIG. 3.

[0090] In the example shown in FIG. 8, the thumbnail display area 202 is reduced in order to expand the document display area 201. Specifically, the size of the thumbnail display area 202 is reduced in the direction along the Y axis. In the thumbnail display area 202, the display size of the thumbnail image PS does not change when the thumbnail display area 202 is reduced, so the lower part of the thumbnail image PS is outside the thumbnail display area 202 and is hidden. However, because the upper part of the thumbnail image PS is visible in the thumbnail display area 202, the user can determine the content of the pages that make up the document based on part of the thumbnail image PS. In other words, the thumbnail image PS is still functioning even if part of the thumbnail image PS is hidden. Therefore, the display mode in the two-page display mode shown in FIG. 8 is useful.

[0091] 9 is an external view of a display device 6 as another application example. The display device 6 is an electronic device configured by connecting two housings 61 and 62 so that they can be opened and closed. The display device 6 has the configuration of the smartphone 1 shown in FIG.

[0092] Furthermore, a display screen 63 is disposed on the housing 61, and a display screen 64 is disposed on the housing 62. The display screens 63 and 64 may have the same configuration as the touch panel 14, for example.

[0093] The display device 6 can be opened and closed by moving the housings 61 and 62 in the direction indicated by the symbol FL and in the opposite direction. By opening the housings 61 and 62, the display device 6 displays an image on a single large display area formed by connecting the display screens 63 and 64.

[0094] When the display method executed by the smartphone 1 is applied to the display device 6, the operation of opening the housings 61 and 62 corresponds to the operation of changing the display area in step S5.

[0095] In this way, the display method described in this embodiment is not limited to the smartphone 1, but can be applied to various devices that have a display screen and a function for changing the display area.

[0096] As described above, the display method according to the embodiment displays a document on the smartphone 1 having the display 141. This display method includes a detection step of detecting a display size when multiple page images PG, which are images of pages constituting a document, are displayed in the document display area 201 arranged on the display screen. This display method also includes a selection step of causing the smartphone 1 to select a display mode for the document display area 201 based on the detection result of the detection step. In the detection step, the smartphone 1 detects a difference in length along the X-axis of the document display area 201 between the overall image width WP, which is the length of the overall image TG formed by arranging multiple page images PG, and the display area width WD, which is the length of the document display area 201. In the selection step, if the difference is equal to or greater than a display setting value, the smartphone 1 selects a two-page display mode in which multiple page images PG are displayed side by side. In the selection step, if the difference is smaller than the display setting value, the smartphone 1 selects a one-page display mode in which one page image PG is displayed. Here, the difference in length corresponds to the margin size BD or the content margin width ND.

[0097] The smartphone 1 includes a touch panel 14 having a display 141. The smartphone 1 includes a detection unit 122 that detects a display size when a plurality of page images PG, which are images of pages constituting a document, are displayed in a document display area 201 arranged on the display 141. The smartphone 1 includes a selection unit 123 that selects a display mode for the document display area 201 based on the detection result of the detection unit 122. The smartphone 1 includes a display control unit 121 that displays the page images PG in the document display area 201 using the touch panel 14 in the display mode selected by the selection unit 123. The detection unit 122 detects a differential length that is the difference along the X axis between an entire image width WP, which is the length of an entire image TG formed by arranging a plurality of page images PG, and a display area width WD, which is the length of the document display area 201. If the differential length is equal to or greater than a display setting value, the selection unit 123 selects a two-page display mode in which a plurality of page images PG are displayed side by side. If the differential length is smaller than the display setting value, the selection unit 123 selects a one-page display mode in which a single page image PG is displayed.

[0098] According to the above display method and the smartphone 1 that executes the above display method, when page images PG of multiple pages of a document are displayed side by side, a display mode can be selected based on the difference in length between the entire image TG and the display area width WD. As a result, when displaying page images of a document, a display mode that matches the shape of the document page is selected, reducing the effort required for the user to switch display modes.

[0099] In the detection step, the display method detects the difference in length when the length of the entire image TG in the direction along the Y axis is made to coincide with the display area height LD, which is the length of the document display area 201. This makes it possible to determine the difference in length in the direction along the X axis when the entire image TG is arranged in as large a size as possible in the document display area 201. Therefore, it is possible to appropriately select the display mode on the premise that the visibility of the page image PG is maximized in the two-page display mode.

[0100] In the detection step, the display method detects the content margin width ND, which is the difference along the X axis between the body width WMC, which is the length of the entire image TG excluding the page margins, and the display area width WD, which is the length of the document display area 201, as a differential length. This allows an appropriate display mode to be selected, assuming that visibility of the body MC is prioritized in two-page display mode. This is particularly useful for users who want to prioritize recognizing the body MC contained in the document.

[0101] The display setting value corresponds to the case where a margin area B occurs between the document display area 201 and the entire image TG, and indicates that the margin size BD, which is the length of the margin area B in the direction along the X axis, is a predetermined length. In this case, the display mode is selected based on the margin size BD, which is the size of the margin area B, so that the display mode can be appropriately selected on the premise that the entire image TG does not protrude from the document display area 201.

[0102] The display setting value corresponds to the case where the display area width WD, which is the length of the document display area 201, and the overall image width WP, which is the length of the entire image TG, are the same, and where a margin area B of a predetermined length or more occurs between the document display area 201 and the entire image TG. In this case, the display mode is selected based on the margin size BD, which is the size of the margin area B. This allows the display mode to be appropriately selected on the premise that the entire image TG does not extend beyond the document display area 201 and that the entire image TG is displayed as large as possible in the document display area 201. This ensures the visibility of the page image PG in the two-page display mode. For example, this prevents the page image PG from being difficult to view when the two-page display mode is selected.

[0103] The display method includes a display step of displaying the page image PG in the document display area 201 in the display mode selected in the selection step. If the two-page display mode is selected in the selection step, a switch button for instructing switching between the two-page display mode and the one-page display mode is displayed in the document display area 201 in the display step. This allows the user to switch the display mode selected in the detection step and the selection step by operating the switch. This improves user convenience regarding switching of the display mode.

[0104] In the above display method, in the selection step, if the shape of the first page among the pages constituting the document is portrait-oriented and the difference length is equal to or greater than the display setting value, the two-page display mode is selected. If the shape of the first page is landscape-oriented, the one-page display mode is selected even if the difference length is equal to or greater than the display setting value. In this case, the shapes of the pages included in the document can be easily identified. Furthermore, since the display mode is selected based on the shape of the page, a display mode suitable for the document can be quickly selected.

[0105] In the above display method, in the selection step, if the proportion of portrait-oriented pages among all pages constituting the document is equal to or greater than a criterion and the difference length is equal to or greater than a display setting value, the two-page display mode is selected. If the proportion of portrait-oriented pages among all pages constituting the document is less than the criterion, the one-page display mode is selected even if the difference length is equal to or greater than a display setting value. In this case, the shapes of the pages included in the document can be more accurately identified. Furthermore, since the display mode is selected based on the shape of the pages, a display mode suitable for the document can be quickly selected.

[0106] In the above display method, a thumbnail display area 202, in which thumbnail images PS of multiple pages are displayed side by side, and a document display area 201 are arranged on the display 141. As a result, thumbnail images PS corresponding to pages of a document and page images PG showing the contents of the pages are arranged on the preview screen 200. Therefore, the user can check the contents of the entire document in the thumbnail display area 202, and can also view the contents of individual pages in the document display area 201.

[0107] The display method includes a selected page display step, which, when an operation to select one of the thumbnail images displayed in the thumbnail display area 202 is received, displays a page image PG of the page corresponding to the selected thumbnail image PS in the document display area 201 in single-page display mode. Thus, the user can select a page in the thumbnail display area 202 and view the contents of the selected page using the page image PG.

[0108] This embodiment shows one mode, and any modifications and applications are possible without departing from the spirit and scope of the present invention.

[0109] In this embodiment, the case where the "display device" is a smartphone 1 will be described, but the present invention is not limited to this. The "display device" may include a processor 12, a memory 13, and a touch panel 14. The "display device" may also be configured as a tablet terminal.

[0110] In this embodiment, a two-page display mode including two page images PG is shown as an example of the multi-page display mode, but the multi-page display mode may be a display mode in which three or more page images PG are arranged side by side. For example, the multi-page display mode may be a display mode in which three page images PG are arranged side by side in the direction along the X-axis.

[0111] The shapes of the button image BT, document display area 201, and thumbnail display area 202 shown in this embodiment can be changed as appropriate. For example, the button image BT may be rectangular or elliptical. The document display area 201 and thumbnail display area 202 may be vertically long, extending in the direction along the Y axis.

[0112] In the present embodiment, an example has been shown in which preview screen 200 is displayed over the entire display 141, but this is not limiting. Preview screen 200 and a screen displayed by another application program may be arranged side by side on display 141. Alternatively, preview screen 200 may be arranged as part of a home screen displayed by OS 131.

[0113] This embodiment describes a display method implemented by the processor 12 of the smartphone 1 executing the OS 131 and APP 132 stored in the memory 13. However, this is merely an example. The program executed by the processor 12 to implement this display method may be configured as a computer-readable recording medium or a transmission medium for transmitting the program. The recording medium may be a magnetic or optical recording medium or a semiconductor memory device. Examples of the recording medium include portable or fixed recording media such as flexible disks, HDDs, CD-ROMs (Compact Disk Read Only Memory), DVDs (Digital Versatile Disks), Blu-ray (registered trademark) discs, magneto-optical disks, flash memories, and card-type recording media. The recording medium may also be a non-volatile storage device such as RAM, ROM, or HDD, which is an internal storage device of a server device configured to communicate with the smartphone 1. In this case, the smartphone 1 downloads the program from the server device.

[0114] The functions of the control unit 11 may be realized by one or more processors or semiconductor chips. The control unit 11 may further include a co-processor such as an SoC (System-on-a-Chip), an MCU (Micro Control Unit), or an FPGA (Field-Programmable Gate Array). The control unit 11 may perform various controls by using both the CPU and the co-processor in cooperation with each other, or by selectively using one of the two.

[0115] The processing units in the flowcharts shown in Figures 5, 6, and 7 are divided according to the main processing content in order to make the processing of the control unit 11 easier to understand, and are not limited by the way in which the processing units are divided or the names of the processing units. The processing units in the flowcharts may be divided into more processing units according to the processing content. One processing unit may also be divided so that it includes more processing. The order of the processing may be changed as appropriate within the scope that does not impair the intent.

[0116] Each functional unit shown in FIG. 1 indicates a functional configuration, and the specific implementation form is not particularly limited. It is not necessary to implement hardware corresponding to each functional unit individually; a configuration in which a single processor executes a program to realize the functions of multiple functional units is also possible. Some of the functions realized by software in the above-described embodiment may be implemented by hardware, or some of the functions realized by hardware may be implemented by software. The specific detailed configurations of the other units of the smartphone 1 may also be changed as desired without departing from the spirit of the invention. [Explanation of symbols]

[0117] 1...smartphone (display device), 2...printer, 6...display device, 10...main body, 11...control unit, 12...processor, 13...memory, 14...touch panel (display unit), 15...orientation sensor, 16...communication interface, 61, 62...housing, 100...printing system, 121...display control unit, 122...detection unit, 123...selection unit, 124...reception unit, 131...operating system, 132...application program, 133...document information storage unit, 134...image information storage unit, 135...setting value, 141...display (display image surface), 142...touch sensor, 200...preview screen, 201...document display area, 202...thumbnail display area, B, B1, B2...margin area, BD, BD1, BD2...margin size (differential length), BT...button image (switch button), DC...document information, LD...display area height, MC...main text, ND, ND1, ND2...content margin width (differential length), PG, PG1, PG2...page image, PP...print image, PS...thumbnail image, SG...thumbnail image group, TG...entire image, WD...display area width, WMC...main text width, WP...entire image width.

Claims

1. A display method for displaying a document on a display device having a display screen, comprising: a detection step of detecting a display size when a plurality of page images, which are images of pages constituting the document, are displayed in a document display area arranged on the display screen; a selection step of selecting a display mode in the document display area based on the detection result of the detection step, In the detecting step, a differential length is detected, which is a difference between a length of an entire image formed by arranging the plurality of page images and a length of the document display area in a direction along a first axis of the document display area; In the selection step, if the difference length is equal to or greater than a display setting value, a multi-page display mode is selected in which a plurality of the page images are displayed side by side, and if the difference length is smaller than the display setting value, a single-page display mode is selected in which one of the page images is displayed; In the detecting step, the difference in length along the first axis between the length of the entire image excluding the margins of the page and the length of the document display area is detected as the differential length.

2. A display method for displaying a document on a display device having a display screen, comprising: a detection step of detecting a display size when a plurality of page images, which are images of pages constituting the document, are displayed in a document display area arranged on the display screen; a selection step of selecting a display mode in the document display area based on the detection result of the detection step, In the detecting step, a differential length is detected, which is a difference between a length of an entire image formed by arranging the plurality of page images and a length of the document display area in a direction along a first axis of the document display area; In the selection step, if the difference length is equal to or greater than a display setting value, a multi-page display mode is selected in which a plurality of the page images are displayed side by side, and if the difference length is smaller than the display setting value, a single-page display mode is selected in which one of the page images is displayed; a display step of displaying the page image in the document display area in the display mode selected in the selection step, a display step of displaying a switch button in the document display area for instructing switching between the multiple page display mode and the single page display mode when the multiple page display mode is selected in the selection step;

3. A display method for displaying a document on a display device having a display screen, comprising: a detection step of detecting a display size when a plurality of page images, which are images of pages constituting the document, are displayed in a document display area arranged on the display screen; a selection step of selecting a display mode in the document display area based on the detection result of the detection step, In the detecting step, a differential length is detected, which is a difference between a length of an entire image formed by arranging the plurality of page images and a length of the document display area in a direction along a first axis of the document display area; In the selection step, if the difference length is equal to or greater than a display setting value, a multi-page display mode is selected in which a plurality of the page images are displayed side by side, and if the difference length is smaller than the display setting value, a single-page display mode is selected in which one of the page images is displayed; In the selection step, selecting the multi-page display mode when the ratio of portrait pages to all the pages constituting the document is equal to or greater than a criterion and the difference length is equal to or greater than the display setting value; When the ratio of portrait pages to all the pages constituting the document is less than a criterion, the one-page display mode is selected even if the difference length is equal to or greater than the display setting value.

4. 4. The method according to claim 1, wherein the detecting step detects the difference length when the length of the entire image in a direction along a second axis perpendicular to the first axis is made to coincide with the length of the document display area. The display method described in.

5. 5. The display method according to claim 1, wherein a thumbnail display area in which thumbnail images of a plurality of the pages are displayed side by side and the document display area are arranged on the display screen.

6. a selected page display step of, when receiving an operation to select one of the thumbnail images displayed in the thumbnail display area, displaying the page image of the page corresponding to the selected thumbnail image in the document display area in the one-page display mode; The display method of claim 5 , comprising:

7. a display unit having a display screen; a detection unit that detects a display size when a plurality of page images, which are images of pages constituting a document, are displayed in a document display area arranged on the display screen; a selection unit that selects a display mode in the document display area based on the detection result of the detection unit; a display control unit that causes the display unit to display the page image in the document display area in the display mode selected by the selection unit, the detection unit detects a differential length that is a difference between a length of an entire image formed by arranging the plurality of page images and a length of the document display area in a direction along a first axis of the document display area; the selection unit selects a multiple page display mode in which a plurality of the page images are displayed side by side when the difference length is equal to or greater than a display setting value, and selects a single page display mode in which a single page image is displayed when the difference length is smaller than the display setting value; The display device, wherein the detection unit detects, as the differential length, the difference in the direction along the first axis between the length of the entire image excluding the margins of the page and the length of the document display area.

8. A display unit having a display screen; a detection unit that detects a display size when a plurality of page images, which are images of pages constituting a document, are displayed in a document display area arranged on the display screen; a selection unit that selects a display mode in the document display area based on the detection result of the detection unit; a display control unit that causes the display unit to display the page image in the document display area in the display mode selected by the selection unit, the detection unit detects a differential length that is a difference between a length of an entire image formed by arranging the plurality of page images and a length of the document display area in a direction along a first axis of the document display area; the selection unit selects a multiple page display mode in which a plurality of the page images are displayed side by side when the difference length is equal to or greater than a display setting value, and selects a single page display mode in which a single page image is displayed when the difference length is smaller than the display setting value; the selection unit displays the page image in the document display area in the selected display mode; a display device that, when the multiple page display mode is selected in the selection section, displays a switch button in the document display area for instructing switching between the multiple page display mode and the single page display mode;

9. A display unit having a display screen; a detection unit that detects a display size when a plurality of page images, which are images of pages constituting a document, are displayed in a document display area arranged on the display screen; a selection unit that selects a display mode in the document display area based on the detection result of the detection unit; a display control unit that causes the display unit to display the page image in the document display area in the display mode selected by the selection unit, the detection unit detects a differential length that is a difference between a length of an entire image formed by arranging the plurality of page images and a length of the document display area in a direction along a first axis of the document display area; the selection unit selects a multiple page display mode in which a plurality of the page images are displayed side by side when the difference length is equal to or greater than a display setting value, and selects a single page display mode in which a single page image is displayed when the difference length is smaller than the display setting value; The selection unit selecting the multi-page display mode when the ratio of portrait pages to all the pages constituting the document is equal to or greater than a criterion and the difference length is equal to or greater than the display setting value; When the proportion of portrait pages among all the pages constituting the document is less than a determination criterion, the display device selects the one-page display mode even if the difference length is equal to or greater than the display setting value.

Images