JP5029962B2 - Terminal device and program thereof - Google Patents

Description

  The present invention relates to a terminal device, and more particularly to a terminal device that informs the user of the area by voice or the like when an arbitrary area such as a map is enclosed with an electronic pen.

  In recent years, pen-type input devices called electronic pens and digital pens have appeared. A typical example is "Anoto pen" developed by Swedish company Anoto. Anotopen is used together with a dedicated paper (anoto paper) on which a predetermined dot pattern is printed. In addition to the normal ink-type pen tip, the Anoto pen is equipped with a small camera for reading the dot pattern on the dedicated paper and a data communication unit.

  When the user writes characters on the special paper with an anotopen or puts a check mark on the image designed on the special paper, the dot pattern printed on the special paper by the small camera as the pen moves , And entry information such as characters and images written by the user is acquired. This entry information is transmitted from the Anotopen by the data communication unit to a terminal device such as a nearby personal computer or mobile phone.

  The system using this anotopen can be used as an input device instead of a keyboard, and is very easy to use for a user who has resistance to using a personal computer or a keyboard. Therefore, a system using an electronic pen is becoming widespread as a technique for digitizing data entered in various business documents, application forms, contracts, and the like.

  By the way, as a method for obtaining the area of a map, there is a method for obtaining an area using a map scale for an area surrounded by a plurality of coordinate values by using a coordinate input device such as a digitizer. In addition, there is an area calculation system that uses an electronic pen to calculate the area inside a closed curve when a user draws a closed curve with the electronic pen on a dedicated paper on which a map is printed. As a method of calculating the area, a method of calculating the area of a polygon obtained by connecting lattice points with a straight line, a method of calculating the number of unit cells in the closed region, and a method of calculating the area by dividing the closed region into triangles and so on. Below are some examples of prior art related to this.

  The “coordinate input processing device” disclosed in Patent Document 1 is an input device such as a digitizer for calculating an area, a volume, and the like on a drawing. When coordinate values are input from the menu sheet, key information corresponding to the contents shown on the menu sheet is recognized and processed. About the area | region enclosed with a several coordinate value, the coordinate value of an area | region is input from on the drawing mounted on the panel, and the length and area in the building etc. of drawing are calculated | required. The volume and the like can be obtained by inputting and calculating the height and width with the numeric keypad. Find the area using the scale of the map.

  The “handwriting data curve approximation method” disclosed in Patent Document 2 is a method for accurately approximating handwritten data input online with a small amount of data using a spline curve. The end points and the turning points are extracted as feature points from the handwritten data ordered according to the stroke. Let this feature point sequence be a node. By perturbing the auxiliary variable at this node, the curve passing through this node is deformed, and the maximum distance between the input data and the spline curve is obtained. When the maximum distance is equal to or smaller than a predetermined value, the auxiliary variable sequence at the node corresponding to the auxiliary variable is stored. That is, the sampling data of the handwritten data is approximated by a spline curve so that the maximum separation distance from the data does not exceed a certain threshold. If the maximum distance between the spline-interpolated curve and the data is equal to or greater than the threshold value, the data giving the distance is newly added as a node and spline interpolation is performed.

  The “encoding sheet for optical reading” disclosed in Patent Document 3 is a sheet having an encoding pattern having a plurality of marks. Each of the marks represents one of at least two different values. The encoding pattern has a plurality of reference positions. Each of the plurality of marks is associated with one reference position, and the value of each mark is determined by the position with respect to the reference position. The basic technique is described about the coordinate calculation of an Anoto dot pattern.

  The “terminal device” disclosed in Patent Document 4 draws a stroke with an electronic pen on a map on which an Anoto dot pattern is printed, and obtains the area of the region. The user designates the target graphic with the electronic pen. The stroke entered on the form is acquired by the terminal device as entry information. The terminal device extracts a stroke from the entry information. The target graphic is specified based on the extracted stroke. Based on the position of the unit graphic included in the definition information, the number of unit graphics included in the target graphic is calculated. The area of the target graphic is calculated based on the number of unit graphics included in the target graphic and the area of the unit graphic included in the definition information. The area of a handwritten figure can be calculated immediately using the electronic pen and the electronic pen form.

Japanese Examined Patent Publication No. 03-050283 Japanese Patent Laid-Open No. 07-121698 Japanese translation of PCT publication No. 2003-511761 JP 2006-309505 A

  However, the conventional area calculation method has the following problems. An accurate area cannot be calculated by the method of calculating the area inside the closed curve by decomposing into unit graphics defined in advance. Actually, the inside of the closed curve drawn by the user cannot always be divided into an integral number of unit graphics, and an error area less than one unit graphic occurs. For this reason, although the obtained area can be used as an approximate value, it cannot be applied to a field where high-accuracy area calculation is required. In the approximation in which a figure is surrounded by a broken line, the area of the arc portion cannot be obtained with high accuracy. Even if interpolation is performed with a smooth function, optimal interpolation cannot always be performed with one type of interpolation function.

  An object of the present invention is to solve the above-described conventional problems and obtain an area of an arbitrary region such as a map with high accuracy using an electronic pen.

  In order to solve the above-described problems, a terminal device according to the present invention receives position coordinate data from an electronic pen or a scanner that calculates the position coordinates of a contact position with respect to a medium, and has a closed region defined by the coordinate data. A terminal device for calculating an area, wherein a receiving unit that receives coordinate data and a plurality of coordinate data received by the receiving unit are sections such that a monotonous increase or a monotonic decrease of the X coordinate continues at least in time series order. The section dividing means to divide, and for each section divided by the section dividing means, interpolation is performed with a plurality of types of interpolation functions, and the position coordinates of each coordinate data are obtained by line segments and various interpolation functions. An interpolation means for calculating an area surrounded by a curve and selecting an interpolation function having the smallest area among the areas; and dividing the closed region into small sections in the X-axis direction, and performing the interpolation Area calculating means for calculating the area of the closed region by calculating the area of the small region in the small region of the closed region using the interpolation function selected by the stage, and integrating the areas of the small regions It is characterized by that.

  According to this configuration, the discrete coordinate data calculated by reading the coded pattern printed on the medium by the electronic pen or the scanner is received by the receiving unit. Then, the section dividing unit divides the plurality of coordinate data received by the receiving unit into sections such that the X coordinate monotonically increases or decreases continuously in time series order so that the coordinate data can be interpolated by the interpolation function. The interpolating means interpolates with a plurality of types of interpolation functions for each section divided by the section dividing means, and is surrounded by a line segment connecting position coordinates of each coordinate data with straight lines and curves obtained by various interpolation functions. The area to be calculated is calculated, and the interpolation function of the smallest area among those areas is selected. Then, the area calculating means divides the closed area into small sections in the X-axis direction, obtains the small section area of the area in the small section of the closed area using the interpolation function interpolated by the interpolation means, To calculate the area of the closed region. As a result, an optimal interpolation function with high reproducibility is selected from a plurality of types of interpolation functions for discrete coordinate data, and the area calculation means integrates the area in the small section using the selected interpolation function. Thus, the area of the area arbitrarily specified by the electronic pen or the scanner can be obtained with high accuracy.

In the terminal device, it is preferable to divide the sections at positions where the included angle formed by three consecutive points is less than the threshold value. With this configuration, the trajectory is divided into sections that are steeper and narrower than the threshold angle, so that the included angle does not fall below the threshold in the interpolated section, and the interpolation by the interpolation function can be smoothed. Can be reproduced more accurately, and the area of the closed region can be obtained with higher accuracy.

  In the terminal device, it is preferable that the interpolation unit is configured to interpolate an end point of the locus when the locus by the electronic pen or the scanner does not form a closed region. The locus by the electronic pen or the scanner does not necessarily form a closed region depending on the user's operation, but even in such a case, the area can be obtained by the area calculating means.

  Further, in the above terminal device, the area calculation means is configured to obtain the area of the closed region by using the intersection as the end point of the trajectory when the end point of the trajectory by the electronic pen or the scanner is separated from each other. Good. Depending on the user's operation, the locus of the electronic pen or the scanner may form a closed region and the end points of the locus may be separated. In such a case, the area can be obtained by the area calculation means. it can.

  The medium has a map printed thereon, and the area calculation means of the terminal device is based on a scale value of the map, on the ground surface in an area drawn on the map by the electronic pen or the scanner. It is good to comprise so that the area of may be calculated. With this configuration, the terminal device can calculate the area of the region on the ground surface corresponding to the specified region by the user specifying an arbitrary region on the map with the electronic pen or the scanner.

  The program according to the present invention is executed by a terminal device that receives position coordinate data from an electronic pen or a scanner that calculates the position coordinates of the contact position on the medium and calculates the area of the closed region defined by the coordinate data. Section for receiving coordinate data and dividing the plurality of coordinate data received by the receiving means so that the X coordinate monotonically increases or decreases continuously in at least chronological order Means, each section divided by the section dividing means is interpolated with a plurality of types of interpolation functions, and is surrounded by a line segment connecting the position coordinates of each coordinate data with straight lines and curves obtained by various interpolation functions. An interpolation means for calculating an area and selecting an interpolation function having the smallest area among the areas; dividing the closed region into small sections in the X-axis direction; The terminal as an area calculating means for calculating the area of the closed region by calculating a small section area of the region in the small section of the closed region using the interpolation function selected by the means and integrating the small section areas The apparatus is made to function.

In such a program, the section dividing means may be configured to divide the section at a position where the included angle formed by three consecutive points is less than a threshold value.

  In the above program, the interpolation means is preferably configured to interpolate an end point of the locus when the locus by the electronic pen or the scanner does not form a closed region.

  Further, in the above program, the area calculating means is configured to obtain the area of the closed region by using the intersection as the end point of the trajectory when the end point of the trajectory by the electronic pen or the scanner is spaced apart from each other. Good.

  Further, the medium is printed with a map, and in the program, the area calculating means is configured to determine a ground surface in an area drawn on the map by the electronic pen or the scanner based on a scale value of the map. It may be configured to calculate the upper area.

  By causing the terminal device to execute the program, the above-described terminal device can be configured.

  With the above configuration, the area of an arbitrary region in a medium such as a map can be obtained with high accuracy using an electronic pen.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to FIGS.

  In the present embodiment, when a user traces and surrounds an arbitrary area of a map drawn on the Anoto paper 3 with the electronic pen 1, the terminal device 2 receives the position coordinates of the contour point to obtain the locus, and obtains the X coordinate. Divides the trajectory into sections that change monotonously and smoothly, interpolates with multiple smooth interpolation functions for each section, selects the optimal interpolation function, and calculates the area of the entire closed region using the optimal interpolation function Then, it is an area calculation system that converts the actual area on the ground surface and informs the user by voice or the like.

  FIG. 1 is a conceptual diagram of an area calculation system in the present embodiment. In FIG. 1, the electronic pen 1 is a device that calculates the position coordinates of the contour point from the Anoto pattern printed on the Anoto paper 3 and transmits data of the position coordinate of the contour point to the terminal device 2. The contour point is a point representing a point on the contour by discrete position coordinates. The contour point position coordinate data includes time information, dot pattern addresses, and the like. The terminal device 2 is a device that receives the position coordinates of the contour point from the electronic pen 1, calculates the area of the closed region surrounded by the trajectory connecting the contour points, converts the area into an area on the ground surface, and notifies it. Anoto pattern and a map are printed on the Anoto paper 3.

  FIG. 2 is a diagram schematically showing how the electronic pen 1 is used. In FIG. 2, a map 4 is a map printed on the Anoto paper 3. An outline 5 is an outline of a map area (“XX island”) traced by the electronic pen 1. The transmission instruction unit 6 is a transmission instruction area printed on the anoto sheet 3.

  FIG. 3 is a conceptual diagram showing the configuration of the electronic pen 1. In FIG. 3, a housing 101 is a case of the electronic pen 1. The opening 102 is a space for illumination and shooting. The ink cartridge 104 contains the ink of the electronic pen 1. The pen point portion 103 is a tip portion for writing characters and tracing the contour 5. The pressure sensor 107 is a means for measuring writing pressure. The CMOS camera 106 is an ultra-small video camera. The LED 105 is an infrared illumination means. The processor 108 is a data processing device that operates according to a program. The memory 109 is a ROM and a RAM that store programs and data. The real time clock 110 is a clock device that generates time information. The communication unit 111 is a short-range wireless transmission unit using a Bluetooth (registered trademark) communication system. The battery 112 is a primary battery or a secondary battery that is a power source of the electronic pen 1.

  FIG. 4 is a diagram for explaining the relationship between the dots of the dot pattern printed on the Anoto paper 3 and the values to which the dots are converted. FIG. 5 is a diagram showing an example of the dot pattern arrangement and the result of the encoding.

  FIG. 6 is a conceptual diagram of the terminal device 2. In FIG. 6, receiving means 21 is means for receiving data on the position coordinates of contour points from the electronic pen 1. The information storage means 22 is a memory for storing data of position coordinates of contour points. The locus determination means 23 is a means for obtaining a locus from the position coordinates of the contour points. The section dividing means 24 is a means for dividing the locus into sections in which the X coordinate value of the contour point changes monotonously and smoothly. The interpolation means 25 is means for selecting an optimal interpolation function by interpolating with a plurality of smooth interpolation functions for each segment of the trajectory. The area calculation means 26 is a means for calculating the area of the entire closed region using an optimal interpolation function for each section of the trajectory and converting it into an actual area on the ground surface. The speaker 27 is an output means for notifying the real area value by voice. The display device 28 is output means for displaying the actual area value in characters.

  FIG. 7 is a diagram illustrating an example of a trajectory. FIG. 8 is a diagram for explaining a method of dividing a trajectory into sections based on the displacement of the X coordinate value of the contour point. FIG. 9 is a diagram for explaining a method of dividing the trajectory into sections based on the angle at which the trajectory is bent. FIG. 10 is a flow showing the processing procedure of section division. FIG. 11 is a diagram illustrating a method of connecting the end points with a straight line to form a closed curve when the end points of the trajectory are separated from each other and are not a closed curve. FIG. 12 is a diagram illustrating a method of forming a closed curve at the intersection when the trajectories intersect. FIG. 13 is a diagram for explaining a method of performing interpolation by dividing a trajectory into sections. FIG. 14 is a diagram illustrating a method for selecting an interpolation function. 15, FIG. 16, and FIG. 17 are diagrams for explaining an area calculation method. FIG. 18 is a flowchart showing a processing procedure for calculating an area.

  The function and operation of the area calculation system configured as described above will be described. First, an overview of the functions of the area calculation system will be described with reference to FIGS. 1 and 2. FIG. 1 shows a relationship among the Anoto paper 3, the electronic pen 1, and the terminal device 2. FIG. 2 shows a state in which the outline 5 of the island of the Anoto paper 3 on which the map 4 is printed is traced with the electronic pen 1. The map 4 is drawn on the Anoto paper 3 on which a dot pattern is printed. In addition to the map 4, the Anoto paper 3 also has a transmission instruction unit 6. The dot pattern is printed on almost the entire surface of the Anoto paper 3. On the dot pattern, characters such as symbols and place names on the map 4 are printed with ink that does not absorb infrared rays. When the user traces the outline 5 of “OO island” on the map 4 with the electronic pen 1, the terminal device 2 obtains the actual area of the island on the ground surface. The user can know the actual area of the area by surrounding the arbitrary area on the map 4 with a closed curve using the electronic pen 1 without being conscious of the dot pattern.

  First, the user brings the pen point portion 103 of the electronic pen 1 into contact with one point of the outline 5 of “XX island”. The electronic pen 1 detects contact with the map (pen down) by changing the writing pressure. The user traces the outline 5 of “XX island” with the electronic pen 1. The electronic pen 1 calculates the position coordinates of the contact position of the pen tip portion 103 about 50 to 100 times per second, for example, 75 times. When the user finishes tracing the outline 5 of “XX island” with the electronic pen 1, the electronic pen 1 is lifted from the map 4 (pen up). The electronic pen 1 detects non-contact (pen-up) by a change in writing pressure. When the user touches the transmission instruction unit 6 of the anoto sheet 3 with the electronic pen 1, the position coordinate data stored in the memory 109 of the electronic pen 1 until then is transmitted to the terminal device 2. Note that the position coordinate data of the contour point may be sequentially transmitted from the electronic pen 1 to the terminal device 2 from pen down to pen up.

  When the electronic pen 1 transmits the entry information including the position coordinate data of the contour point to the terminal device 2, the terminal device 2 receives the entry information from the electronic pen 1 and closes the trajectory connecting the contour points. Find the area of the region. This is converted into an actual area on the surface of the earth and notified by voice. Since the scale information is stored in the terminal device 2 so as to correspond to the address of the dot pattern, the scale information is acquired based on the address of the dot pattern. The scale information may be the actual surface length per unit length on the map, such that 1 cm on the map corresponds to 5 km on the surface, or 1: 25000 or 1/25000. Such a scale ratio may be used.

  Next, the electronic pen 1 will be described with reference to FIG. As shown in FIG. 3, the electronic pen 1 includes a processor 108 configured by a CPU, a memory 109 such as a ROM and a RAM, a communication unit configured by an antenna, a transmission circuit, and the like inside a housing 101. 111, a battery 112, an LED 105, a CMOS camera 106, a real-time clock 110, a pressure sensor 107, and an ink cartridge 104. The tip of the ink cartridge 104 is a pen tip portion 103.

  The battery 112 is for supplying power to each component in the electronic pen 1. For example, the power supply of the electronic pen 1 itself is turned on / off by detaching the cap (not shown) of the electronic pen 1. The real time clock 110 transmits time information indicating the current time (time stamp) and supplies the time information to the processor 108. The pressure sensor 107 detects the pressure applied through the ink cartridge 104 from the pen tip portion 103 when the user writes a locus on the anoto paper 3 with the electronic pen 1, that is, the writing pressure, and sends the value to the processor 108. .

  The processor 108 switches on / off the switches of the LED 105 and the CMOS camera 106 based on the writing pressure data supplied from the pressure sensor 107. That is, when the user writes a locus on the Anoto paper 3 with the electronic pen 1, the pen tip 103 is applied with a writing pressure, and when the pressure sensor 107 detects a writing pressure exceeding a predetermined value, the processor 108 Then, it is determined that the user has started entry, and the LED 105 and the CMOS camera 106 are operated.

  The LED 105 and the CMOS camera 106 are attached in the vicinity of the pen tip portion 103 of the electronic pen 1. An opening 102 is formed in a portion of the housing 101 facing the LED 105 and the CMOS camera 106. The LED 105 irradiates infrared rays toward the vicinity of the pen tip portion 103 on the Anoto paper 3. The area is slightly deviated from the position where the pen tip 103 contacts the Anoto 3 paper. The CMOS camera 106 captures a dot pattern in the area illuminated by the LED 105 and supplies image data of the dot pattern to the processor 108. An imaging region by the CMOS camera 106 is a range including a size of about 2 mm × about 2 mm as shown in FIG. Imaging by the CMOS camera 106 is performed about 50 to 100 times per second.

  Since carbon absorbs infrared rays, the infrared rays irradiated by the LED 105 are absorbed by the carbon contained in the dots. Therefore, the dot portion has a small amount of infrared reflection, and the portion other than the dot has a large amount of infrared reflection. By discriminating the photographing result of the CMOS camera 106 with a threshold value, it is possible to distinguish the dot area containing carbon from the other area by the difference in the amount of reflected infrared light. Since the ink on which the map 4 is printed does not contain carbon, the dot pattern can be easily recognized. It should be noted that a dot pattern printed with fluorescent ink may be used, and another coding pattern such as a two-dimensional code pattern may be used instead of the dot pattern.

  While the user is tracing the contour, the processor 108 continuously calculates the XY coordinates on the Anoto paper 3 of the point traced by the user from the dot pattern of the image data supplied by the CMOS camera 106. Go. That is, the processor 108 converts the dot pattern image data supplied by the CMOS camera 106 into a data array. Further, it is converted into an X coordinate bit value and a Y coordinate bit value. The XY coordinates and the dot pattern address are calculated from the data array by a predetermined calculation method. Then, the processor 108 associates the current time transmitted from the real-time clock 110, the writing pressure data, the dot pattern address, and the XY coordinates. Since the 6 × 6 dot pattern on the Anoto paper 3 does not overlap within the Anoto paper 3, when the user traces the outline with the electronic pen 1, the traced position corresponds to any position on the Anoto paper 3. This can be specified by coordinate calculation by the processor 108. The communication unit 111 transmits the XY coordinates to the terminal device 2. Transmission by the communication unit 111 is performed by wireless transmission of Bluetooth (registered trademark).

  Next, a dot pattern (coded pattern) will be described with reference to FIGS. 4 and 5. A dot pattern is printed on the Anoto paper 3. The electronic pen 1 has a pen tip portion 103 similar to a normal ink pen. When the user writes a closed curve or the like on the Anoto paper 3 by the pen tip portion 103 in the same manner as a normal ink pen, the electronic pen 1 The dot pattern printed on the Anoto paper 3 is read locally and continuously along the handwriting of the leading portion 103, the coordinates of the local position on the Anoto paper 3 are calculated, and the coordinate data and the like are transmitted to the terminal device 2. To do. The electronic pen 1 is used in the vicinity of the terminal device 2 so that data can be reliably transmitted to the terminal device 2. The terminal device 2 calculates the area of the closed region surrounded by the handwriting of the electronic pen 1 based on the received coordinate data and the like.

  As shown in FIG. 4, each dot of the dot pattern is associated with a predetermined value depending on its position. In other words, each dot is associated with a value of 0 to 3 depending on which direction the top, bottom, left, or right is shifted from the reference position of the grid (intersection of the vertical line and horizontal line). The value of each dot can be further converted into a first bit value for the X coordinate and a second bit value for the Y coordinate. The position coordinates on the Anoto paper 3 are determined by the combination of the information thus associated.

  As shown in FIG. 5 (a), 6 × 6 dots are arranged within a range of about 2 mm in length and width so that a unique pattern can be obtained no matter where 6 × 6 dots are taken from Anoto paper 3 Has been. The dot pattern formed by these 36 dots holds position coordinates (a position of the dot pattern on the anoto sheet 3) and a dot pattern address (coded pattern address). Accordingly, the position can be detected in units of about 1/3 mm in the vertical direction and the horizontal direction. FIG. 5B is a diagram in which each dot shown in FIG. 5A is converted into a corresponding value based on the regularity shown in FIG. 4 according to the shift direction from the reference position of the lattice. This conversion is performed by the electronic pen 1 that captures an image of a dot pattern.

  Next, the terminal device 2 will be described with reference to FIG. The terminal device 2 is a personal computer, a mobile phone, or a mobile terminal. As hardware, a communication circuit capable of data communication with the electronic pen 1, a processor such as a CPU, a memory such as a ROM, a RAM, and a hard disk, a speaker, and a display are provided. The terminal device 2 processes the XY coordinate data received from the electronic pen 1 with a dedicated program, and calculates the area of the closed region.

  FIG. 6 is a functional block diagram of the terminal device 2. As shown in FIG. 6, the terminal device 2 includes a receiving unit 21, an information storage unit 22, a trajectory determining unit 23, a section dividing unit 24, an interpolation unit 25, an area calculating unit 26, a speaker 27, And a display device 28. Physically, the information storage means 22 is constituted by a memory such as a ROM, a RAM, or a hard disk. The receiving means 21 is composed of a data communication unit, a processor, and the like. The display device 28 is a liquid crystal display or the like. The trajectory determining means 23, the section dividing means 24, the interpolation means 25, and the area calculating means 26 are functionally realized by a dedicated program.

  The receiving unit 21 is a unit that receives position coordinate data transmitted by the communication unit 111 of the electronic pen 1 and includes an antenna, a wireless circuit, and the like. The information storage means 22 is a memory for storing the position coordinate data acquired from the electronic pen 1 and the area of the closed region calculated by the area calculation means 26 and the area on the ground surface. Further, the information storage means 22 stores the scale value of the map drawn in the map area 4 in correspondence with the dot pattern address in the map area 4 of the Anoto paper 3.

  The trajectory determining unit 23 obtains a trajectory from the position coordinates of a plurality of contour points received by the receiving unit 21 and stored in the information storage unit 22. A trajectory is a set of contour points arranged in chronological order of handwriting, and it is assumed that the contour points are connected by straight lines in that order. The section dividing means 24 divides the locus into sections in which the X coordinate of the position coordinates of the contour point changes monotonously and smoothly. The smooth change of the position coordinates means that the angle at which the trajectory is bent is equal to or smaller than a predetermined threshold value. The interpolation means 25 interpolates the trajectory with a plurality of smooth interpolation functions for each section, and selects an optimal interpolation function among them. Here, the interpolation function is a differentiable function. The area calculation means 26 calculates the area of the entire closed region using an optimal interpolation function for each section, and converts the area on the map into the actual area on the ground surface with reference to the scale value. The speaker 27 notifies the value of the real area by voice. The display device 28 displays the actual area value in characters. A processing method from locus determination to area calculation will be described in detail below.

  First, the trajectory determination process by the trajectory determination means 23 of the terminal device 2 will be described. The entry information received by the receiving means 21 from the electronic pen 1 is stored in the information storage means 22, and the locus determining means 23 is a time-series locus based on the position coordinates of the contour points and the time information included in the entry information. Create data. Here, in the state where the user hardly moves the electronic pen 1, many of the same position coordinates are acquired, so that the overlapping position coordinates are represented by the first one position coordinates, and the position coordinates of the contour points are represented. It is desirable to have the function adopted as The example shown in FIG. 7 is schematically shown, and the coordinate data is calculated about 75 times per second by the electronic pen 1, so that the coordinate data is actually more precisely defined.

Next, with reference to FIGS. 7 and 8, a method will be described in which the segment is divided by the segment dividing unit 24 so that the locus is continuously increased or decreased monotonously in the X coordinate. Includes cases where there is no change in monotonic increase / decrease. _Let (X _n , Y _n ) be the coordinates of the contour points obtained when tracing the map 4 with the electronic pen 1. Each contour point has an X coordinate and a Y coordinate. First, (X _s , Y _s ) and the end point (X _e , Y _e ) are extracted with reference to time information. As described above, the contour points are t (0), t (1),. The section dividing means 24 divides each section so that the X coordinate of the trajectory is continuously increased or decreased monotonously. In the example shown in FIG. 7, the X coordinate monotonously increases from t (0) to t (5), the X coordinate monotonously decreases from t (5) to t (11), and t (11) to t (15). The X coordinate increases monotonically at t (15) to t (19), the X coordinate decreases monotonically, the t coordinate increases from t (19) to t (23), and t (23) to t (27 ), The X coordinate monotonously decreases, so the contour points t (5), t (11), t (15), t (19), t (23) Let it be a point.

Next, a method in which the section dividing unit 24 further divides the locus into sections based on the included angle will be described with reference to FIG. The section dividing means 24 applies to contour points t (0), t (1),..., T (k-2), t (k-1), t (k), t (k + 1),. , The angle θ (0),..., Θ (k-1), θ (k), θ (k + 1), θ, which is the included angle formed by the line segment connecting the three consecutive contour points and smaller than 180 degrees Find (k + 2), ... Of these included angles, θ (0),..., Θ (k-1), θ (k), θ (k + 1), θ (k + 2),. The threshold angle may be changed as appropriate. As a result, by dividing the trajectory into sections where the curve is narrower and steeper than the threshold angle, interpolation using the interpolation function can be made smooth. In the example of FIG. 9, t (5), t (11), t (15), t (19), and t (23) are extracted. It is. Therefore, t (0) to t (5), t (5) to t (11), t (11) to t (15), t (15) to t (19), t (19) to t (23 ), T (23) to t (27). In this way, the contour points are divided into sections so that the X coordinate is monotonously increased or monotonously decreased, and further, a point where the angle between the three consecutive contour points is less than the threshold is obtained, and that point is also divided into sections. Therefore, boundaries other than the monotonically increasing / monotonically decreasing boundary points may be used as the boundaries depending on the included angle. When the contour points are continuous in parallel to the Y axis, the start point and end point may be set as the boundary points of the section.

  Next, another processing procedure of section division by the section dividing means 24 will be described with reference to FIG. In this procedure, whether or not three consecutive contour points should be divided into sections is determined simultaneously from the viewpoints of monotonic increase / monotonic decrease in X-coordinate and included angle. The section dividing unit 24 sets an initial value 0 to the contour point number n (step 21), and checks whether the X coordinate values of three consecutive contour points are monotonously increasing or monotonically decreasing (step 22). If the displacement of the X coordinate is neither monotonously increasing nor monotonously decreasing (step 22: No), the section dividing unit 24 selects the center contour point among the three contour points as the boundary point t (n + 1) of the section. (Step 25). On the other hand, if it is monotonously increasing or monotonically decreasing (step 22: Yes), the section dividing means 24 obtains the included angles of the three contour points (step 23). Then, the section dividing unit 24 checks whether the included angle is less than the threshold (step 24). If the included angle is less than the threshold (step 24: Yes), the center contour point t (n + 1) among the three contour points. ) As the boundary point of the section (step 25). After that, or when it is determined that the included angle is not less than the threshold value (step 24: No), the section dividing unit 24 examines all the contour points to check whether or not the end point is reached (step 26). Otherwise (step 26: Yes), the section dividing means 24 adds (increments) 1 to the contour point number n (step 27), returns to step 22 and repeats the process. If it is an end point (step 26: Yes), the section dividing means 24 ends the process.

  Next, trajectory end point processing by the interpolation means 25 will be described with reference to FIGS. 11 and 12. The handwriting drawn by a person with the electronic pen 1 is not necessarily a closed curve. Therefore, if there is an intersection point in the trajectory, the intersection point is set as a boundary point of the section, the curve data from the start point to the intersection point and the curve data from the intersection point to the end point are discarded, and are not considered as the trajectory for obtaining the area. If there is no intersection in the locus, the start point and end point are connected by a straight line to form one section, and a linear function representing the straight line is set as an interpolation function. There are the following two types of cases that can occur specifically. As shown in FIG. 11, when the start point Sp and the end point Ep are separated from each other and the locus is not a closed curve, the start point Sp and the end point Ep are connected by a straight line. Unless drawn intentionally, the distance between the start point Sp and the end point Ep is very short, and the other sections are not affected. In addition, as shown in FIG. 12, when the start point Sp and the end point Ep are separated from each other and the locus is a closed curve, the intersection on the way to the start point Sp and the end point Ep is set as the boundary of the section. Treat as a point. A point A in FIG. 12 is an intersection obtained by the end point processing. If the intersection of the trajectories is not a lattice point, the closest lattice point is taken as the intersection. Point B and point C are boundary points of the section when the trajectory is divided into sections based on the monotonic increase / monotonic decrease reference of the X coordinate.

Next, the interpolation processing by the interpolation means 25 will be described with reference to FIG. The electronic pen 1 captures a dot pattern 75 times per second and obtains position coordinates (X _n , Y _n ). The obtained position coordinates are continuous along the traced path. When the moving speed of the electronic pen 1 is fast, the distance between sample points (acquired contour points) becomes long. In this case, it is possible to reproduce the trajectory of the electronic pen 1 in a natural shape by interpolating with a smooth curve rather than performing linear interpolation between sample points, and an accurate area can be obtained.

As shown in FIG. 13, the interpolation means 25 divides each section into D ₀ = [t (0) to t (5)], D ₁ = [t (5) to t (11)], D ₂ = [ t (11) to t (15)], D ₃ = [t (15) to t (19)], D ₄ = [t (19) to t (23)], D ₅ = [t (23) to t (27)]. Spline interpolation or Lagrangian interpolation is performed for each of the obtained sections D _{0 to} D ₅ . In the case of spline interpolation, an interpolation function is obtained so as to smoothly connect between contour points. In the case of Lagrangian interpolation, interpolation is performed by a high-order function that passes through all contour points in a section unit. A curve in which contour points are connected by an interpolation function is called an interpolation locus.

Lagrangian interpolation is a method of interpolating (N + 1) data of contour points (X _n , Y _n ) (n = 0, 1, 2,..., N) with an Nth order polynomial. Higher orders may vibrate (Runge phenomenon). Spline interpolation is a method of interpolating contour points (X _n , Y _n ) (n = 0, 1, 2,..., N) with an n-order function (for example, a cubic function). In this method, an interpolation function S _j (X) (j = 0, 1, 2,..., N−1) is obtained for the interval [X _j , X _{j + 1} ]. The more sample points, the better the accuracy of approximation. The interpolation function Y = S (X) is defined in each section [X _j , X _{j + 1} ] (j = 0, 1, 2,..., N−1). Therefore, S (X) = S _j (X) in the section of X _j ≦ X ≦ X _{j + 1} . [X _j , X _{j + 1} ] is not a small interval of integration but an interval in which points at both ends of the interval are sample points. In practice, cubic spline interpolation is often used. Other suitable known interpolation methods such as spline interpolation or Lagrangian interpolation may be used.

  Next, a method for determining the optimum interpolation function by the interpolation means 25 will be described with reference to FIG. The interpolation unit 25 selects an appropriate interpolation curve based on the size relationship between the linearly interpolated locus and the interpolation curve. However, when there are a large number of sample points in one section, the interpolating means 25 uses splines rather than Lagrange interpolation. By selecting the interpolation, problems with Lagrange interpolation such as “Runge phenomenon (vibration)” can be avoided. If the number of sample points is small, a more accurate interpolation function can be selected by selecting Lagrange interpolation or spline interpolation.

As shown in FIG. 14A, the interpolation means 25 interpolates each sample point with various interpolation functions (spline interpolation and Lagrange interpolation in the example of FIG. 14) in each section D _j to obtain an interpolation curve. . Here, an interpolation function by spline interpolation in the section D _j is D _j _spline (x), and an interpolation function by Lagrange interpolation is D _j _Lagrange (x). Next, as shown in FIG. 14 (b), the interpolation means 25, the line segment connecting each contour point and the area surrounded by the curve of D _j _spline (x), the line segment connecting each contour point, and D _The area surrounded by the curve of j_Lagrange (x) is obtained, and the values of the areas are G _pj _spline and G _pj _Lagrange. Then, as shown in FIG. 4C, the interpolation unit 25 obtains the minimum value of G _pj _spline and G _pj _Lagrange, and sets the interpolation function forming the area of the minimum value as G _fj (x). . This G _fj (x) is selected as the optimum interpolation function.

Next, an area calculation process by the area calculation unit 26 will be described with reference to FIGS. After performing the segmentation process by the segmentation unit 24, the interpolation process by the interpolation unit 25, and the end point process, the area calculation unit 26 calculates the area by using the optimum interpolation function G _fj (x) for each segment. An interpolation function in each section is G _fj (x) (j = 0, 1,..., 5). The section D _j corresponds to the optimum interpolation function G _fj (x). When integration is performed in a small section having an interval in the X direction of dx, interpolation functions G _fj (x) constituting the closed region of the small section are expressed in order from f ₀ (x), f ₁ ( x), and so on. Therefore, even for the same interpolation function in the same interpolation interval, different f _i (x) may be defined depending on the small interval.

_{i in} f _i (x) is numbered for each small section. Even for the same interpolation function, the number assigned to i can vary depending on how many curves in the Y direction are present. This is a function defined for the sake of convenience for integral calculations. f _i (x) is an interpolation function in a sampling interval (between contour points) including a small interval. If the small interval is larger than the sampling interval, the integral calculation becomes difficult. Therefore, as shown in FIG. 16, the small interval is made smaller than the sampling interval. j is the number of the small section. When the spline interpolation function is adopted as the interpolation function in the section D _j , the function is defined for each sampling section, and therefore, when the small section is moved in the X direction, a different function is obtained.

As shown in FIG. 17, when a contour point enters the small section dx, the distance between the contour point and both ends of the small section dx is compared, and the spline interpolation function with the larger distance is defined as f _i (x). adopt. If the distance is the same, the smaller k (contour point number) is adopted. In this method, the width dx of the small section can be arbitrarily set, but the calculation is complicated. In order to avoid this, the width dx of the small section may be selected so as to be the minimum value of the contour point interval.

Here, the area calculating means 26 obtains the minimum value Xmin and the maximum value Xmax of the X coordinate among the coordinates forming the closed curve, and divides it into a plurality of small sections whose length in the X direction is dx. And introduce variable k,
When Xmin, k = 0,
When Xmin + dx, k = 1,
When Xmin + 2dx, k = 2,
When Xmin + 3dx, k = 3,
......
When Xmax, k = kmax
Let k be the rank of the small section existing in the closed region in the closed curve.

a0 = Xmin, bmax = bkmax = Xmax,
If the small section dx in the rank k is defined by the X coordinates aj and bj such that the general formula of the area M _j in the closed curve in the small section dx between the jth X coordinate aj and bj is expressed by the following expression: The However, N = (number of interpolation functions defined in the Y direction in the small section dx) / 2.

Therefore, for example, in FIG. 15, M _j in the small section dx between aj and bj is composed of one region M _j and is as follows.

Further, for example, in FIG. 15, M _j in the small section dx between aj ′ and bj ′ is composed of three regions m ₁ , m ₂ , and m ₃ and is as follows.

The area calculating means 26 obtains the area M _j for each of the plurality of small sections dx defined between the minimum value Xmin and the maximum value Xmax of the X coordinate in this way, and the sum of these is calculated for the closed region in the closed curve. Calculated as area.

Furthermore, the area calculation unit 26 refers to the scale information stored in the information storage unit 22 and acquires a scale value corresponding to the dot pattern address included in the entry information. Then, if the position coordinates are based on the actual size of the Anoto paper 3, the area calculating means 26 corresponds to the closed region in the closed curve from the area on the map and the scale value calculated as described above. The area S on the ground surface to be calculated is calculated as follows. Here, c is a scale value.

When calculating the area S on the ground surface, the area calculating means 26 causes the speaker 27 to notify the value of the area S by voice or by the display device 28 by characters. For example, a notification such as “the area is OO km ² ” is given.

Summarizing the area calculations as described above, a flow shown in FIG. 18 is obtained. That is, the terminal device 2 receives the entry information including the position coordinate data transmitted from the electronic pen 1 by the receiving means 21 and stores the entry information by the information storage means 22 (step 1). Subsequently, the trajectory determining means 23 obtains the trajectory from the position coordinate data, and obtains the maximum value and the minimum value of the X coordinate (step 2). The section dividing means 24 divides the trajectory into sections so that the X coordinate monotonously increases or decreases monotonically and the included angle does not become less than the threshold in each section (step 3). Then, the interpolation means 25 performs end point processing (refer to FIGS. 11 and 12) such as linear interpolation between the end points when the trajectories do not have intersections and the end points are separated (step 4). Further, the interpolation means 25 performs spline interpolation and Lagrangian interpolation for each section, compares the area surrounded by the line segment of the contour point and the interpolation curve, and obtains the optimum interpolation function that forms the minimum area (step 5). ). After that, the area calculating means 26 takes out the interpolation function in the first small section (d = 0 of k = 0) (step 6), and obtains the area in the small section by integration using the optimal interpolation function that forms the closed curve in the small section. (Step 7). Subsequently, the area calculating means 26 performs calculation while checking whether there is an uncalculated small section (step 8). If there is an uncalculated small section (step 8: Yes), the area calculating means 26 calculates the next small section. An interpolation function is extracted (step 9), and the processing from step 7 is repeated. If there are no uncalculated subsections (step 8: No), the area calculation means 26 integrates the areas of the respective subsections and converts the area on the map into the actual area on the ground surface using the scale factor (step). 10). Finally, the area calculating means 26 informs the actual area S by voice or screen through the speaker 27 or the display device 28 (step 11).

  As described above, when the user traces and surrounds an arbitrary area of the map 4 drawn on the Anoto paper 3 with the electronic pen 1, the terminal device 2 receives the position coordinates of the contour point to obtain the locus, Divide the trajectory into sections where the X coordinate changes monotonously and smoothly, interpolate with multiple smooth interpolation functions for each section, select the optimal interpolation function, and integrate the area of the closed region by integration using the optimal interpolation function Since the calculation is made so that the actual area on the ground surface is notified to the user by voice or the like, the area of an arbitrary area on the map 4 can be obtained with high accuracy.

  The present invention is not limited to the above embodiment.

  In the above-described embodiment, the electronic pen 1 with an ink cartridge is used as a device for obtaining the position coordinates. Instead, an ink cartridge is not attached, and pen down and pen up can be recognized by detecting pen pressure. A pen-type scanner may be used.

Further, in the above-described embodiment, the section dividing unit 24 divides the time-series position coordinates into sections that are continuously increased or decreased monotonically in the X coordinate, and the included angle formed by the three consecutive points is a threshold value. The sections are divided so as not to be less than this, but the present invention is not limited to this, and the section dividing means 24 may only divide the time-series position coordinates so as to be continuously monotonically increasing or decreasing in the X coordinate. If the X coordinate is monotonously increasing or monotonically decreasing, spline interpolation or Lagrangian interpolation is possible in each section. Also, instead of dividing the sections by comparing three consecutive included angles and thresholds, the sections may be divided by another method so that the discrete coordinate data in the sections change smoothly.

  In the above embodiment, the interpolation unit 25 uses the two functions of the spline function and the Lagrangian function to obtain the optimum interpolation function by comparing the area of the region surrounded by the line segment of the contour point and the interpolation curve. For example, the same interpolation function may be compared using a plurality of interpolation functions with different orders, or may be compared using a function other than a spline function or a Lagrangian function.

  In the above embodiment, the horizontal direction of the Anoto paper 3 is the X axis and the vertical direction is the Y axis. However, the present invention is not limited thereto, and the vertical direction may be set as the X axis and the horizontal direction as the Y axis. The XY axes may be tilted with respect to the Anoto paper 3 in accordance with features such as topography appearing on the map.

  The terminal device of the present invention is most suitable as a system for obtaining an area on a map. It can also be used as a system for obtaining areas other than maps. Moreover, it can also be used to obtain an area of an arbitrary closed region in the object by superimposing semi-transparent Anoto paper on the object. Since the area of a three-dimensional object can be determined approximately, it can be used to determine the partial area of the head for wig preparation and the like.

It is a conceptual diagram of the area calculation system in one Embodiment of this invention. It is a figure which shows a mode that a closed curve is drawn on the map of Anoto paper with an electronic pen. It is a conceptual diagram which shows the structure of an electronic pen. It is a figure explaining the relationship between the dot of the dot pattern printed on Anoto paper, and the value into which the dot is converted. It is a figure which shows an example of the arrangement | sequence of a dot pattern, and the result of the encoding. It is a functional block diagram of a terminal device. It is a figure which shows the example of the locus | trajectory by the time-sequential position coordinate data calculated with the electronic pen. It is a figure explaining the method of dividing a locus | trajectory into a section based on the monotone increase of the X coordinate value of a locus | trajectory shown in FIG. It is a figure explaining the method of dividing a locus into sections based on a included angle in the locus shown in FIG. It is a flow which shows the process sequence of division. It is a figure which shows the method of connecting an end point with a straight line and making it a closed curve, when the end points of a locus | trajectory are mutually separated and are not a closed curve. It is a figure which shows the method of making a closed curve at an intersection when a locus | trajectory cross | intersects. It is a figure explaining the method of dividing the locus | trajectory shown in FIG. It is a figure explaining the selection method of the optimal interpolation function. It is a figure explaining the method to divide | segment into the small area dx to a X-axis direction, and to calculate an area by integration using an optimal interpolation function. It is a figure explaining application of the interpolation function by the positional relationship of the interpolation area and small area of an interpolation function. It is a figure explaining application of the interpolation function by the positional relationship of the interpolation area and small area of an interpolation function. It is a flow which shows the area calculation process in a terminal device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Electronic pen, 2 ... Terminal device, 3 ... Anoto paper, 4 ... Map, 5 ... Contour, 6 ... Transmission instruction | indication part, 7 ... Interpolation locus | trajectory, 21 ... Reception means, 22 ... Information storage means, 23 ... Trajectory determination means , 24 ... section dividing means, 25 ... interpolation means, 26 ... area calculating means, 27 ... speaker, 28 ... display device, 101 ... housing, 102 ... opening, 103 ... pen tip part, 104 ... ink cartridge, 105 ... LED, 106 ... CMOS camera, 107 ... pressure sensor, 108 ... processor, 109 ... memory, 110 ... real time clock, 111 ... communication unit, 112 ... battery.

Claims (10)

A terminal device that receives position coordinate data from an electronic pen or a scanner that calculates position coordinates of a contact position on a medium, and calculates an area of a closed region defined by the coordinate data,
Receiving means for receiving coordinate data;
Section dividing means for dividing the plurality of coordinate data received by the receiving means into sections so that the monotonous increase or the monotonic decrease of the X coordinate continues in at least chronological order;
For each section divided by the section dividing means, interpolation is performed with a plurality of types of interpolation functions, and the area surrounded by the line segment connecting the position coordinates of each coordinate data with straight lines and the curves obtained by various interpolation functions An interpolation means for calculating and selecting an interpolation function of the smallest of these areas;
Dividing the closed region into small sections in the X-axis direction, using the interpolation function selected by the interpolation means, obtaining a small section area of the region in the small section of the closed region, and integrating the small section areas And a terminal area calculating means for calculating the area of the closed region. The terminal device according to claim 1, wherein the section dividing unit further divides the section at a position where an included angle formed by three consecutive points is less than a threshold value.   The terminal device according to claim 1, wherein the interpolation unit interpolates an end point of the trajectory when the trajectory by the electronic pen or the scanner does not form a closed region.   The end point of the trajectory by the electronic pen or the scanner is separated from the end point of the trajectory by the electronic pen or the scanner, but when there is an intersection, the area of the closed region is obtained using the intersection as the end point of the trajectory. 4. The terminal device according to claim 1. The medium has a printed map,
The area calculation means calculates an area on the ground surface in an area drawn on the map by the electronic pen or the scanner based on a scale value of the map. The terminal device as described in any one. A program that is executed by a terminal device that receives position coordinate data from an electronic pen or scanner that calculates the position coordinates of a contact position on a medium and calculates the area of a closed region defined by the coordinate data,
Receiving means for receiving coordinate data;
Section dividing means for dividing the plurality of coordinate data received by the receiving means into sections so that the monotonous increase or the monotonic decrease of the X coordinate is continuous at least in chronological order;
For each section divided by the section dividing means, interpolation is performed with a plurality of types of interpolation functions, and the area surrounded by the line segment connecting the position coordinates of each coordinate data with straight lines and the curves obtained by various interpolation functions An interpolation means for calculating and selecting the interpolation function of the smallest of these areas,
Dividing the closed region into small sections in the X-axis direction, using the interpolation function selected by the interpolation means, obtaining a small section area of the region in the small section of the closed region, and integrating the small section areas The program causes the terminal device to function as area calculation means for calculating the area of the closed region. The program according to claim 6, wherein the section dividing unit further divides the section at a position where an included angle formed by three consecutive points is less than a threshold value.   The program according to claim 6 or 7, wherein the interpolation means interpolates an end point of the locus when the locus by the electronic pen or the scanner does not form a closed region.   The area calculation means obtains the area of the closed region by using the intersection point as an end point of the trajectory when the end points of the trajectory by the electronic pen or the scanner are spaced apart from each other. The program according to claim 1. The medium has a printed map,
The area calculation means calculates an area on the ground surface in an area drawn on the map by the electronic pen or the scanner based on a scale value of the map. The program as described in any one.

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