An information processing device includes a storage storing handwritten data generated according to handwritten input to a sheet-like recording medium, in a first file corresponding to a first page and a second file corresponding to a second page, and a controller which determines whether or not to couple (combine) the first and second files based on a first identification result identifying a region of the first page in which the handwritten data has been written or a region of the first page in which the handwritten data has not been written and a second identification result identifying a region of the second page in which the handwritten data has been written or a region of the second page in which the handwritten data has not been written. In response to a determination to couple the first and second files, the controller controls coupling of the first and second files.

BACKGROUND

Technical Field

The present disclosure relates to an information processing device and an information processing method.

Description of the Related Art

There has been known a handwritten data drawing/input device which, when a user writes text or draws pictures on a paper medium such as a writing paper, can electronically capture the handwritten text or the hand-drawn pictures as handwritten data. This kind of device is generally configured to include a position detection device such as a digitizer, and a stylus configured to function both as an indicator and as a ballpoint pen. The paper medium is arranged on a touch surface of the position detection device. According to this configuration, when a user writes text or draws pictures on the surface of a paper medium by using the ballpoint pen functionality of the stylus, the position detection device can acquire a series of coordinate data indicating a movement track of the stylus on the touch surface. The series of coordinate data thus acquired becomes handwritten data indicating the handwriting of the electronic pen.

Incidentally, the paper medium used in the handwritten data drawing/input device has a plurality of pages in some cases. In this case, the handwritten data drawing/input device needs to create handwritten data separately for each page. Otherwise, the handwriting written on each of the plurality of pages of the paper medium is superimposed on each other onto one page on a screen. In this regard, Japanese Patent No. 6005880 discloses a technique in which an operation button is provided in a position detection device for switching to a new file to accumulate coordinate data, so as to create a file of handwritten data for each page.

BRIEF SUMMARY

Incidentally, in order to save power, the position detection device is designed to automatically enter a stand-by mode in some cases in the case where a non-operation state continues for a predetermined period of time (for example, 15 minutes). In this case, some devices are designed so that the file for accumulating the coordinate data is temporarily closed at the time of entering the stand-by mode, and after returning (or waking up) from the stand-by mode, the coordinate data is accumulated in a new file.

However, according to such a stand-by process, even if the user writes on the same page of the paper medium before and after the stand-by mode, the coordinate data after returning from the stand-by mode is accumulated in a file different from the file used before entering into the stand-by mode. In this case, the handwritten text may be recorded in a divided state into a plurality of files although the handwritten text is written on the same page of a paper medium. Then, the handwritten text may be misunderstood as being written on a plurality of pages. A need exists for improvement in this regard.

In addition, according to the technique disclosed in Japanese Patent No. 6005880, when the user forgets to press the operation button, the handwritten data written on each of the plurality of pages of the paper medium is accumulated in one file. This results in that the pages of the paper medium do not have a one-to-one correspondence with the files. A need exists for improvement in this regard.

According to one aspect of the present disclosure, an information processing device and an information processing method are provided which are capable of associating pages of a paper medium with files for accumulating handwritten data in a one-to-one correspondence.

An information processing device according to the present disclosure includes a storage unit configured to store handwritten data generated according to handwritten input to a sheet-like recording medium, in the form of a first file corresponding to a first page and a second file corresponding to a second page. The information processing device includes a control unit configured to determine whether or not to couple (or combine) the first file and the second file on the basis of a first identification result identifying a region of the first page in which the handwritten data has been written or a region of the first page in which the handwriting not been written, the first identification result being based on the handwritten data stored in the first file, and a second identification result identifying a region of the second page in which the handwritten data has been written or a region of the second page in which the handwriting data has not been written, the second identification result being based on the handwritten data stored in the second file. In response to a determination that the first file and the second file are to be coupled, the control unit controls coupling of the first file and the second file.

An information processing method according to the present disclosure is executed by an information processing device having a storage unit that stores handwritten data generated according to handwritten input to a sheet-like recording medium in the form of a first file corresponding to a first page and a second file corresponding to a second page. The method includes determining whether or not to couple (or combine) the first file and the second file on the basis of a first identification result identifying a region of the first page in which the handwritten data has been written or a region of the first page in which the handwriting data has not been written, the first identification result being based on the handwritten data stored in the first file, and a second identification result identifying a region of the second page in which the handwritten data has been written or a region of the second page in which the handwriting data has not been written, the second identification result being based on the handwritten data stored in the second file. The method includes controlling coupling of the first file and the second file in response to a determination that the first file and the second file are to be coupled.

According to the present disclosure, it is possible to prevent handwritten information written on the same page of a paper medium from being inadvertently recorded in a plurality of files.

DETAILED DESCRIPTION

FIG.1is a diagram for depicting a position detection device10and a tablet terminal30according to an embodiment of the present disclosure. The position detection device10is a device that incorporates a capacitance touch panel and detects, based on the touch panel, a position of a stylus S on a touch surface10a. Instead of the capacitance touch panel, the position detection device10may incorporate an electromagnetic induction touch panel, for example.

The stylus S is configured to support an active capacitive system, and functions as an indicator for indicating a position on the touch surface10a, and also functions as a writing tool (for example, as a ballpoint pen) for visually leaving handwriting on a surface of a sheet-like recording medium such as paper. The tablet terminal30is an information processing device having a touch screen31configured to receive touch input. The position detection device10and the tablet terminal30are mutually connected by wireless communication such as via a Bluetooth (registered trademark) technology, or by wired communication such as via a universal serial bus (USB).

An X direction and a Y direction depicted inFIG.1are directions corresponding to a lateral direction and a depth direction, respectively, when viewed from the user of the position detection device10. The position detection device10has a rectangular shape in which one side in the Y direction is longer than one side in the X direction, and is used, as depicted inFIG.1, in a state where a rectangular note pad NP as a sheet-like recording medium slightly smaller than the position detection device10is mounted on the touch surface10a. As will be described in detail later, when the user writes text letters or draws pictures on the surface of the note pad NP by using the stylus S as a writing tool, a track (trace) of the stylus S is detected as a series of coordinate data by the position detection device10. The tablet terminal30acquires the series of coordinate data from the position detection device10to generate stroke data and displays the generated stroke data on the touch screen31.FIG.1depicts a state in which a letter string “MAKING IDEAS” written on the note pad NP by the user is displayed on the touch screen31of the tablet terminal30according to these processes. It should be noted that the sheet-like recording medium is generally made of paper material but may be a material made of a resin or the like.

As depicted inFIG.1, the position detection device10is configured to have a power supply/operation button11, a power supply lamp12, a paper storage section13, and a stylus storage section14. Of these, the power supply/operation button11is a switch for turning on/off the power supply of the position detection device10, and is also a switch for receiving a page break instruction from the user. In the case where the power supply/operation button11is continuously depressed for a predetermined period of time or more (that is, in the case where it is depressed for a long time), the position detection device10turns on or off the power supply of the position detection device10. On the other hand, in the case where the power supply/operation button11is depressed but the depressed state is eliminated before reaching the predetermined period of time (that is, in the case where it is depressed for a short time), the position detection device10receives a page break instruction from the user. In addition, the power supply lamp12is a lamp that is turned on when the power supply of the position detection device10is on and is turned off when the power supply of the position detection device10is off.

Here, the page is a concept corresponding to a block of handwritten data generated according to handwritten input, or to a file including the block of handwritten data. Therefore, the handwritten data or the file including the handwritten data generated by handwritten input to each page of the sheet-like recording medium formed of a plurality of pages is associated with each page. Furthermore, in the case where the handwritten data generated by handwritten input on the same page of the sheet-like recording medium is divided into a plurality of pieces of handwritten data or files based on the stand-by mode operation, discussed in the background section above, or based on an operation by the user, each of the divided handwritten data or files is associated with a corresponding page.

The paper storage section13is an opening configured to receive a backboard of the note pad NP. The user places the note pad NP on the position detection device10by inserting the backboard of the note pad NP into the paper storage section13. The stylus storage section14is a recess for securely receiving the stylus S. When the user does not use the stylus S, the stylus S may be fixed to the position detection device10by inserting a clip of the stylus S into the opening of the paper storage section13and fitting a top end portion of the stylus S in the recess of the stylus storage section14.

As a basic operation, the position detection device10is configured to accumulate a series of sequentially-detected coordinate data in one file. Therefore, if the user writes on a plurality of pages while turning pages of the note pad NP, the coordinate data related to the handwriting of different pages is included in one file. When the series of coordinate data thus accumulated is displayed on the touch screen31of the tablet terminal30, the handwriting related to a plurality of pages is superimposed on each other and displayed together.

Since this would hinder practical utility, the position detection device10is configured so that the user can instruct a page break. Specifically, when the user depresses the power supply/operation button11for a short time, the position detection device10receives the page break instruction as described above, and switches to a new file as the accumulation destination of the coordinate data. Since a file of handwritten data is created for each page by this operation, the handwriting related to a plurality of pages is prevented from being superimposed on each other to be displayed together on the touch screen31as described above.

However, in practice, the user may sometimes forget to depress the power supply/operation button11for a short time. As a result, the handwriting related to a plurality of pages may be superimposed and displayed together on the touch screen31. Thus, the tablet terminal30has a configuration for dividing the file after the file has been created, as will be described in detail later as a second aspect of the present disclosure.

In the case where a non-operation state continues for a predetermined period of time (for example, 15 minutes), in order to save power, the position detection device10is designed to automatically enter the stand-by mode. The non-operation state in this case includes non-detection of the coordinate data of the stylus S. The position detection device10having entered the stand-by mode is configured to save power consumption by not performing any operation other than, for example, detection of the depression of the power supply/operation button11. The position detection device10having detected the depression (long or short depression) of the power supply/operation button11while in the stand-by mode is configured to return from the stand-by mode to start any stopped operation other than the detection of a depression of the power supply/operation button11.

Here, in order to prevent destruction or loss of a file, the position detection device10is configured, when entering the stand-by mode, to temporarily close the file in which the coordinate data is being accumulated. In addition, after returning from the stand-by mode, a new file is generated, and the coordinate data is stored in the new file. According to such a configuration of the position detection device10, while the destruction or loss of a file can be prevented, even if the user writes on the same page of the paper medium before and after the stand-by mode, the coordinate data after returning from the stand-by mode is accumulated in a new file different from the file used before entering the stand-by mode. As a result, the handwritten data written on the same page is treated as data written on another page. Thus, the tablet terminal30has a configuration for consolidating (combining) the handwritten data written on the same page into one file after multiple files have been created. This point will be described in detail later as a first aspect of the present disclosure.

FIG.2is a diagram for depicting internal configurations of the position detection device10and the tablet terminal30. As depicted in the drawing, the position detection device10is configured to further include a touch panel15, a sensor controller16, a memory17, and a wireless communication unit18. In addition, the tablet terminal30is configured to include, in addition to the touch screen31depicted inFIG.1, a wireless communication unit32, a control unit33, and a memory34.

The touch panel15is a projected capacitive touch panel (PCAP) which supports the position detection of the stylus S based on an active electrostatic system and the position detection of a finger based on a capacitance system.

FIG.3is a diagram for depicting a detailed configuration of the touch panel15. As depicted in the drawing, the touch panel15is configured to have a plurality of linear electrodes15xand15yarranged so as to cover the entire touch surface10a. The plurality of linear electrodes15xeach extending in the Y direction are arranged at equal intervals in the X direction orthogonal to the Y direction. The plurality of linear electrodes15yeach extending in the X direction are arranged at equal intervals in the Y direction. Each of the plurality of linear electrodes15xand15yis connected to the sensor controller16.

The explanation will continue by referring back toFIG.2. The sensor controller16is an integrated circuit that detects the position of the stylus S by using the touch panel15and also receives data transmitted by the stylus S. The sensor controller16also performs a process of detecting the position of a finger within the touch surface10aby using the touch panel15. The position of the stylus S is detected by an active electrostatic system, and the position of a finger is detected by a capacitance system.

The detection of the stylus S by the sensor controller16will be described while referring back toFIG.3. The sensor controller16is configured so as to periodically transmit an uplink signal by using all of the plurality of linear electrodes15x(or the plurality of linear electrodes15y) depicted inFIG.3. The uplink signal plays a role of informing the stylus S of the transmission timing of a downlink signal and a role of transmitting a command to the stylus S.

The stylus S having received the uplink signal transmits the downlink signal at the timing indicated by the uplink signal. In the case where the stylus S is not yet paired with the sensor controller16, the downlink signal is configured using an unmodulated burst signal having a predetermined time length. Hereinafter, the burst signal will be referred to as a “position signal.” On the other hand, in the case where the stylus S is paired with the sensor controller16, the downlink signal is configured to include the position signal having a shorter time length and a data signal. The data signal is a signal modulated by data requested (instructed) by a command included in the uplink signal. Examples of data transmitted by the data signal include a pen pressure value indicating a pressure applied to a tip end of the stylus S, switch information indicating an on/off state of a button provided on the stylus S, a pen identification (ID) pre-stored in the stylus S, and the like.

In the case where the sensor controller16is not yet paired with the stylus S, the sensor controller16attempts to detect the downlink signal transmitted by the stylus S throughout the touch surface10aby scanning all of the plurality of linear electrodes15xand15yafter transmitting the uplink signal (global scan). In the case where the downlink signal is detected by this detection, the sensor controller16detects the position of the stylus S on the basis of the reception intensity of the downlink signal at each of the plurality of linear electrodes15xand15y, and performs a predetermined pairing operation with the stylus S. Upon completion of this operation, the sensor controller16and the stylus S are paired with each other.

After transmitting the uplink signal, the sensor controller16paired with the stylus S attempts to detect the position signal transmitted by the stylus S with only a part (portion) of the touch surface10aby scanning only a predetermined number of linear electrodes15xand15yin the vicinity of the last detected position of the stylus S among the plurality of linear electrodes15xand15y(local scan). Then, the position of the stylus S is newly acquired on the basis of the reception intensity of the downlink signal at each of the linear electrodes15xand15y. Subsequently, the sensor controller16receives the data signal transmitted by the stylus S by scanning only one of the plurality of linear electrodes15xand15yin the vicinity of the last detected position of the stylus S. Then, the data transmitted by the stylus S is acquired by demodulating the received data signal.

The explanation will continue by referring back toFIG.2. The memory17is a storage unit configured to manage data in units of files. The sensor controller16is configured to write coordinate data indicating the position of the stylus S detected by the active capacitive system and data received from the stylus S (hereinafter collectively referred to as “handwritten data”) to a file in the memory17. Accordingly, a series of handwritten data depicting the handwriting of the user is accumulated in the file. The respective files are stored in the memory17in an ordered state such as #1, #2, in the order of generation.

FIG.4is a diagram for depicting handwritten data output from the sensor controller16and files for storing the handwritten data. The sensor controller16according to this example is configured to generate handwritten data including coordinate data (X, Y) indicating the position of the stylus S, a pen pressure value P and switch information SW1and SW2received from the stylus S, and time stamp information indicating time T at which the position is detected, and output the generated handwritten data to the memory17. Hereinafter, the explanation will be continued on the premise of this example.

The sensor controller16is configured to generate a new file in the memory17in the case where the position detection device10is turned on, in the case where the position detection device10returns from the stand-by mode, and in the case where the short depression of the power supply/operation button11is detected. InFIG.4, a file #1 is a file generated according to the power-on of the position detection device10, a file #2 is a file generated according to the returning from the stand-by mode, and a file #3 is a file generated according to the detection of the short depression of the power supply/operation button11. When a new file is generated, the sensor controller16changes the output destination of the handwritten data to the new file.

The explanation will continue by referring back toFIG.2. The wireless communication unit18is a functional unit that extracts the file accumulated in the memory17and transmits the extracted file to the tablet terminal30. The extraction and transmission of the file by the wireless communication unit18may be executed according to a transmission instruction from the tablet terminal30, or may be executed according to the user activation of an operation element on the position detection device10. In addition, in the case where the position detection device10and the tablet terminal30come close to a communicable distance, transmission may be automatically executed. In addition, the wireless communication unit18may transmit the accumulated handwritten data, not in units of files, but together with information specifying a page on which the handwritten data is written each time the handwritten data for one coordinate is accumulated (written) in the memory17by the sensor controller16. In this manner, the handwritten data can be displayed in real time on the touch screen31of the tablet terminal30. In this case, the file management is performed by the tablet terminal30.

Moving to the tablet terminal30, the wireless communication unit32receives the handwritten data from the position detection device10and supplies the handwritten data to the control unit33. The control unit33generates stroke data as drawing vector data on the basis of a series of handwritten data supplied from the wireless communication unit32, and stores the stroke data in the memory34.

FIG.4also depicts the stroke data stored in the memory34by the control unit33. As depicted in the drawing, the stroke data is data including one or more pieces of handwritten data, and the control unit33is configured to collectively store the one or more pieces of stroke data in the memory34per file. Here, the memory34is a storage unit configured to manage data in units of files, as similar to the memory17. The order of the files in the memory17is also maintained in the memory34.

A method of generating the stroke data by the control unit33will be described in detail. In order to generate the stroke data from a series of handwritten data, the control unit33first determines delimiters (breaks) between the strokes by referring to the pen pressure value P in each handwritten data. That is, since the unit handwritten data in which the corresponding pen pressure value P is zero is acquired by the pen in a hover state, the data does not contribute to handwriting. Therefore, the control unit33excludes such handwritten data from the generation target of the stroke data, and determines the portion including the excluded handwritten data as a stroke delimiter. Then, one stroke data is generated by a set of one or more pieces of handwritten data delineated by the delimiter.

When generating the stroke data, the control unit33refers to the time stamp information of each handwritten data to assign order information to each of a series of generated stroke data. Accordingly, each stroke data in the file stored in the memory34is ordered in the handwriting order. In the example ofFIG.4, the data written as “order n” (n is a natural number) is the order information, and the natural number n indicates the handwriting order.

The control unit33is also configured to have a function of extracting a file stored in the memory34, rendering each stroke data included in the file, and displaying the result on the touch screen31, and a function of recognizing a touch operation of the user on the touch screen31and performing a process according to the content of the touch operation.

In addition to the above functions, the control unit33is configured to perform a function of coupling (combining) files and/or dividing a file stored in the memory34. Of these, the function of coupling files corresponds to the above-described first aspect of the present disclosure, and the function of dividing a file corresponds to the above-described second aspect of the present disclosure. Hereinafter, the processes performed by the control unit33will be described in detail in the order of the first aspect of the present disclosure and the second aspect of the present disclosure. It should be noted that although the embodiments will be described by taking, as an example, a case where the file storing the stroke data (the file stored in the memory34) is coupled or divided, the control unit33may also couple or divide the file storing the handwritten data (the file stored in the memory17). In this case, it may be preferable that the control unit33temporarily copies or creates a file storing the handwritten data in the memory34, and then performs the coupling or dividing processing of the copied or created file.

FIGS.5A and5Bare diagrams each depicting an example of the written state of pages #1 and #2 according to the first aspect of the present disclosure. Pages #1 and #2 are pages corresponding to two files #n and #n+1, respectively, among the plurality of files stored in order in the memory34. The English sentences written on pages #1 and #2 are written by the user in order from the top on one page of a paper medium. However, when the user interrupts the handwriting for a while in the middle of the writing and the position detection device10enters the stand-by mode, the file is divided into two files in the memories17and34as depicted inFIGS.5A and5B.

Here, in the case where sentences are written on one page of the paper medium, the user proceeds to write, line by line, from one end of the page in the Y direction (a writing start end) toward the other end in the Y direction (a writing termination end), and proceeds to write, per line, from one end in the X direction toward the other end in the X direction. It should be noted that the “one end in the Y direction” as the writing start end is the “upper end” in the case where the user writes horizontally on the paper medium. The “one end in the X direction” as the writing start end may be the “left end” in the case where the user writes vertically. Hereinafter, the explanation will be continued on the premise of horizontal writing, but the present disclosure is also applicable to support vertical writing.

Since the user proceeds to write as described above, in the case where the file is changed in the middle of one page of the paper medium, as shown inFIGS.5A and5B, in page #2 corresponding to the second file #n+1, a region having a predetermined length from the upper end becomes a blank region EA and, furthermore, the lower end F2y (terminal end) of the blank region EA is positioned substantively below (toward the writing termination end side) the lower end E1y (terminal end) of the written region FA in page #1 corresponding to the first file #n (or “E1y+10” in the illustrated example ofFIG.5A, as will be more fully described below). The relative positions of F2yand E1ymay be referred to as a positional relation. It should be noted that “substantively” is used here to consider a case where each line is written upward to the right, or a case where switching of the file occurs in the middle of a line, as in the examples ofFIGS.5A and5B. The control unit33according to the first aspect of the present disclosure is configured to determine whether or not to couple (combine) files #n and #n+1 by determining the positional relation, and to execute the coupling process of files #n and #n+1 according to the determination result. Using the coupling process, each handwritten input divided into a plurality of files can be connected (combined) again as a series of handwritten input.

FIG.6is a flowchart for depicting a file coupling process according to the first aspect of the present disclosure. Hereinafter, the process of the control unit33according to the first aspect of the present disclosure will be specifically described with reference to this flowchart.

The control unit33first assigns 1 to a variable n (step S1). Subsequently, the control unit33attempts to select two files #n and #n+1 stored in the memory34(step S2), and determines whether the two files #n and #n+1 have been successfully selected (step S3). If files #n and #n+1 have not been selected (N to step S3), the control unit33terminates the file coupling process.

Next, the control unit33sets effective regions EZ in pages #1 and #2 corresponding to files #n and #n+1, respectively (step S4). As depicted inFIGS.5A and5B, the effective region EZ is a region within a page sandwiched between safe zones SZ provided at the upper end and lower end of each page. In general, the safe zone SZ is a region in which the user does not perform a writing action. The specific size of each safe zone SZ may be set by the user.

Next, on the basis of the handwritten data stored in file #n, the control unit33acquires a first identification result identifying a region of page #1 in which the handwritten data has been written or a region of page #1 in which the handwritten data has not been written (step S5). It may be preferable that the first identification result is generated on the basis of the terminal end information (the lower end E1y depicted inFIG.5A) of the handwritten data stored in file #n, which corresponds to the written region FA described above. In this case, it may be preferable that the written region FA is a region including all the stroke data corresponding to file #n. Specifically, the maximum value and minimum value are acquired from the y coordinates (coordinate information) included in the coordinates forming each stroke data stored in file #n, and a region sandwiched between a straight line extending in the X direction at a position corresponding to the acquired maximum value and a straight line extending in the X direction at a position corresponding to the acquired minimum value is detected as the written region FA. It should be noted that, in the example ofFIG.5A, the upper end of the written region FA coincides with the upper end of the effective region EZ, but it is not necessary for the upper end of the written region FA to coincide with the upper end of the effective region EZ.

Next, on the basis of the handwritten data stored in file #n+1, the control unit33acquires a second identification result identifying a region of page #2 in which the handwritten data has been written or a region of page #2 in which the handwritten data has not been written (step S6). It may be preferable that the second identification result is generated on the basis of the start end information (the lower end F2y depicted inFIG.5B) of the handwritten data stored in file #n+1, which corresponds to the blank region EA which, among one or more blank regions included in page #2, is positioned on the upper side (the writing start end side) when viewed from the written region in page #2. Specifically, the written region of page #2 is detected similarly to step S6, and the region on the upper side (the writing start end side) of the written region in which no stroke data exists is detected as the blank region EA.

Subsequently, the control unit33determines whether or not the blank region EA has been detected in step S6(step S7), and in the case where it is determined that the blank region EA has not been detected, n is incremented by 1 (step S12), and the process returns to step S2. In the case where there is no blank region above the written region of page #2, file #n+1 cannot be coupled to file #n. Therefore, by performing step S7, the processing to not couple multiple files can be accelerated.

The control unit33having determined the blank region EA has been detected in step S7executes steps S8to S11described below to determine whether or not to couple files #n and #n+1 on the basis of the positional relation of the regions in which the handwritten data has been written or the regions in which the handwritten data has not been written in pages #1 and #2, that is, on the basis of the first identification result and the second identification result.

Specifically, the control unit33first acquires the lower end E1y of the written region FA detected in step S5(step S8), and acquires the lower end F2y of the blank region EA detected in step S6(step S9). Then, the control unit33determines whether or not to couple files #n and #n+1 on the basis of the acquired lower ends E1y and F2y (step S10). Specifically, the determination in step S10is made by determining whether or not F2y is smaller than E1y+10 (F2y<E1y+10) in the Y direction (seeFIGS.5A and5B). It should be noted that the number “10” used in the determination is merely an example, and, for example, a predetermined value set by the user may be used.

That F2y is smaller than E1y+10 means that the lower end of the blank region EA detected in step S6is positioned substantively below the lower end of the written region FA detected in step S5. This means that there is a high possibility that the written region FA detected in step S5can be placed in the blank region EA detected in step S6, and thus the control unit33performs a process of coupling file #n+1 to file #n in the case where F2yis determined to be smaller in step S10(step S11). Specifically, the coupling may be performed by moving all the stroke data in file #n+1 to the end of file #n. In step S11, additionally, the numbers of files #n+2 and later (#n+3, #n+4, etc.) are respectively increased (up) by 1 to be #n+1, #n+2, #n+3, etc. (because file #n+1 has been combined into file #n and no longer exists). On the other hand, in the case where F2yis determined to be not smaller in step S10, the control unit33increments n by 1 (n+1) (step S12) without coupling the files and returns the process to step S2.

After executing step S11, the control unit33returns the process to step S2without incrementing n. Accordingly, it is possible to appropriately couple the files even in the case where the entry to the stand-by mode is performed a plurality of times during writing on one page of the paper medium.

As described above, according to the function of the tablet terminal30according to the first aspect of the present disclosure, since a plurality of files storing the results of writing on the same page of the paper medium can be coupled and combined into one file, it is possible to correctly associate the pages of the paper medium with the files for storing the handwritten data in a one-to-one correspondence even in the case where the entry of the position detection device10to the stand-by mode disrupts a one-to-one correspondence between pages of the paper medium and files.

Next,FIG.7is a diagram depicting a sample result of drawing one or more pieces of stroke data stored in file #n on the touch screen31, which can be resolved according to the second aspect of the present disclosure. The user writes the English sentences depicted inFIG.5Aon one page of the paper medium and then turns over the page to write the English sentences depicted inFIG.5Bon another page of the paper medium, but as a result of forgetting to perform the short depression of the power supply/operation button11when turning over the page, the stroke data corresponding to each of the two pages is accumulated in one file #n. As a result, the text handwritten over the two pages of the paper medium is superimposed and displayed together in one page #1 on the touch screen31, as shown inFIG.7.

FIG.8andFIG.9are diagrams for depicting point numbers and page coordinates, respectively. The control unit33is configured to use the point numbers and the page coordinates to execute the process according to the second aspect of the present disclosure.

The point number is attribute information based on the number of strokes corresponding to handwritten input, and is herein a number indicating a serial number of each point within one or more pieces of stroke data included in one file.FIG.8depicts an example in which the point numbers are assigned to end points of the stroke data as well as to points on curves having a predetermined curvature value or more of the stroke data. However, the points to which the point numbers are assigned are not limited to the illustrated examples, and may be, for example, control points used when drawing the stroke data (e.g., control points of a Catmull-Rom curve), or points included in each of one or more pieces of handwritten data used by the control unit33to generate the stroke data (e.g., coordinate data).

The page coordinate is a number indicating a serial number of each cell obtained by dividing one page into a lattice shape, and is assigned to each cell so that the number increases along the direction in which the letter string is written as depicted inFIG.9.FIG.9depicts an example in which one page is divided into 425 cells.

FIG.10is a diagram in which only the letters corresponding to the point numbers 1 to 899 among the plurality of letters depicted inFIG.7are superimposed and written on the page coordinates depicted inFIG.9. In addition,FIG.11is a diagram in which only the letters corresponding to the point number 900 and later among the plurality of letters depicted inFIG.7are superimposed and written on the page coordinates depicted inFIG.9. As can be understood from these drawings, assuming that the user writes sentences on a page in the above-described writing style (that is, the writing style in which the sentences are written from one end of the page in the Y direction toward the other end in the Y direction, line by line, and the sentences are written from one end in the X direction toward the other end in the X direction, per line), in the case where data handwritten over two pages is superimposed and displayed together on the touch screen31, a number of the corresponding page coordinates is significantly reduced (e.g., halved) due to switching of pages.

FIG.12is a diagram for schematically depicting the relation between the point numbers and the page coordinates with respect to one file including data handwritten over two pages. As depicted in the drawing, while the point numbers (1 to 902 inFIG.12) corresponding to the handwriting on the first page can be approximated to a straight line, the point numbers (903 and later inFIG.12) corresponding to the handwriting on the second page are plotted at positions significantly deviated from the approximated straight line. Therefore, the control unit33according to the second aspect of the present disclosure is configured to obtain a correlation coefficient between the point number and the page coordinate, to determine the presence or absence of page turning on the basis of the obtained correlation coefficient, and to execute a file dividing process according to the determination result. That is, in order to prevent the handwritten input, which should be divided into plural pieces of handwritten data corresponding to plural pages and recorded in plural files respectively, from being recorded instead in one file, the above-described attribute information indicative of page turning, for example, may be used to execute the file dividing process according to the second aspect of the present disclosure.

FIG.13andFIG.14are flowcharts for depicting the file dividing process according to the second aspect of the present disclosure. Hereinafter, the process of the control unit33according to the second aspect of the present disclosure will be specifically described with reference to these flowcharts.

The control unit33first acquires file #n to be processed (step S20). Subsequently, the control unit33determines total N points Pi(i=1 to N) on the basis of one or more pieces of stroke data included in the acquired file #n (step S21). The variable i is the above-described point number. The control unit33then assigns 1 to the variable i and 0 to a variable MPC (step S22). The variable MPC is a variable for storing a number of points Piwhich are candidate points to be moved to another file in the process to be described below.

Next, the control unit33acquires the page coordinate Ciof the point Pi(step S23), and derives the correlation coefficient r of the point P1by the following Equation (1) (step S24). Note that in Equation (1), SPPis the deviation square sum obtained by Equation (2), SCCis the deviation square sum obtained by Equation (3), and SPCis the deviation product sum obtained by Equation (4). In addition, <P> in Equations (2) and (4) is the average value of the points P1to Pi, and <C> in Equations (3) and (4) is the average value of the page coordinates C1to Ci.

Next, the control unit33determines whether or not the number of points P1to Pi(=i) exceeds 20% of the total number of points N (i/N>0.2) (step S25). If not, it is determined whether or not the correlation coefficient r derived in step S14is smaller than 0.9 (step S26), and if it is determined to be smaller, the file dividing process is terminated. According to this processing, in the case where the relation between the point number and the page coordinate clearly does not satisfy the relation depicted inFIG.12and therefore it is not appropriate to apply the second aspect of the present disclosure, such as in the case where what is written on the page is not a sentence but a drawing, the file dividing process can be terminated. It should be noted that in the case where the variable i is too small (for example, i/N<0.1), it is conceivable that the value of the correlation coefficient r derived in step S14is not stable, and thus the determination result in step S26may be forcibly set to “N” (negative).

In the case where it is determined in step S26that the correlation coefficient r is not smaller than 0.9, the control unit33increments the variable i by 1 (i+1) (step S29), and determines whether or not the variable i is larger than N (step S30). Here, if the variable i is larger than N, the control unit33terminates the file dividing process. In this case, the file is not divided. On the other hand, if the variable i is not larger than N, the process continues by returning to step S23.

The control unit33having determined that i/N is larger than 0.2 in step S25then determines whether or not the correlation coefficient r derived in step S14is smaller than 0.9 (step S26), and in the case where it is determined to be not smaller, the control unit33clears a movement candidate collection and assigns 0 to the variable MPC (step S28). The movement candidate collection is a table for temporarily storing the point Pithat has become the movement candidate to be moved to another file. As will be described later, the condition for storing the points Piin the movement candidate collection is that the correlation coefficient r is smaller than 0.9, but if the correlation coefficient r becomes 0.9 or more at the points Pithereafter, it is highly likely that the points Piheretofore stored in the movement candidate collection are outliers that should be ignored. According to the process in step S28, it is possible to exclude the points Pithat are such outliers from the movement candidates. After executing step S28, the control unit33moves to step S29to continue the process.

In the case where it is determined in step26that the correlation coefficient r is smaller than 0.9, the control unit33enters the point Piin the movement candidate collection as depicted inFIG.14(step S31), and increments the variable MPC by 1 (MPC+1) (step S32). Then, it is determined whether or not the number of points Pistored in the movement candidate collection (=MPC) is smaller than 10% of the total number of points N (MPC/N<0.1) (step S33). If MPC is determined to be smaller than 10%, the control unit33moves to step S29inFIG.13to continue the process.

On the other hand, if MPC is determined to be not smaller than 10% in step S33, the control unit33enters all of the point Pi+1and subsequent points (Pi+2, Pi+3, etc.) in the movement candidate collection (step S34), and displays a user confirmation screen (step S35). The user confirmation screen allows the user to confirm whether or not the file may be divided. In the user confirmation screen, it may be preferable to arrange information to allow the user to identify any stroke data related to one or more points Pistored in the movement candidate collection. The control unit33having displayed the user confirmation screen determines the confirmation result entered on the screen by the user (step S36).

In the case where it is determined in step S36that the user has approved the file division, the control unit33moves the stroke data related to one or more points Piin the movement candidate collection to a new file (step S37), and terminates the file dividing process. Accordingly, the file is divided into a portion before the user has turned the page and a portion after the user has turned the page. In the case where it is determined in step S36that the user has disapproved the file division, the control unit33terminates the file dividing process without executing step S37.

As described above, according to the function of the tablet terminal30according to the second aspect of the present disclosure, since one file storing the results of writing on a plurality of pages of the paper medium can be divided to multiple pages, it is possible to associate the pages of the paper medium with the files storing the handwritten data in a one-to-one correspondence even in the case when the user forgets to press the power supply/operation button11to thereby disrupt a one-to-one correspondence between pages of the paper medium and files.

In addition, since the user confirmation is requested in steps S35and S36, it is possible to prevent the tablet terminal30from automatically executing an inappropriate file division process. This is particularly effective in the case where text sentences and figures (drawings) are mixed in the handwriting of the user.

Although the preferred embodiments of the present disclosure have been described above, it is obvious that the present disclosure is not limited to the particular embodiments, and further various embodiments are possible based on the present disclosure.

For example, in the above embodiments, the tablet terminal30embodying both the first aspect and the second aspect of the present disclosure has been described, but the tablet terminal30may embody only one of the aspects.

In addition, in connection with the first aspect of the present disclosure, the control unit33may store predetermined tag information in the memory17when entering a sleep mode. By referring to the tag information when returning from the sleep mode, the control unit33can recognize that an entry to the sleep mode has occurred in the middle of the writing, to ensure the continuity of a series of handwritten data written in one page of the paper medium.

In addition, the tablet terminal30may be configured to always transit from step S24to step S27without executing steps S25and S26among the processes depicted inFIG.13. Similarly, the tablet terminal30may be configured to always transit from step S34to step S37without executing steps S35and S36among the processes depicted inFIG.14.

In addition, the user confirmation process similar to that in steps S35and S36ofFIG.14may be executed before step S11ofFIG.6. Accordingly, it is possible to prevent the tablet terminal30from automatically executing an inappropriate file coupling (combining) process.