JP2011180711A - Image display device, image display method, and screen display program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain an increase in information amount of display data displayed, together with an existing map image. <P>SOLUTION: An image display device includes a correspondence relation acquiring unit for acquiring from information encoded in a first area of a map image, a correspondence relation between a first coordinate system on the map image and a second coordinate system for defining a display position of display data to be placed on the map image; a coordinate transformation unit for acquiring area information indicative of a presence range, on the second coordinate system of a second area including the first area, according to the correspondence relation; and a display data acquiring unit for acquiring the display data corresponding to the area information. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a print image reading technique.

  Various services using map information are provided to users through a network, for example. For example, a user accesses a server on a network using various information devices such as a mobile phone, a portable information terminal, and a personal computer. Then, the user can download the map information from the server on the network and display it on the information device. Moreover, the user can acquire various information related to the area indicated by the map together with the displayed map information. For example, the user can designate the type of facility to be displayed, and the facility corresponding to the designated type can be displayed superimposed on the map.

JP 2008-234684 A JP 2006-163992 A JP 2002-23734 A

  When obtaining information on a map using the information device as described above, the user desires depending on hardware limitations such as screen size, communication speed, processor processing capacity, memory capacity, etc. There are cases where information cannot be obtained accurately.

  On the other hand, when a conventional paper medium, print medium, or the like is used, the hardware limitation of the information device is unlikely to occur as when the information device is used. However, there is a problem that the user can acquire only information printed on paper. For example, the user cannot acquire information on a store or facility installed after map information is printed on paper, information on a building constructed after map information is printed on paper, and the like from printed paper. In addition, the user cannot acquire information about facilities provided after the signboard including the map is produced from the produced signboard.

  According to one aspect of the invention, the second coordinate system defines a display position of display data to be arranged in the first coordinate system on the map image and the map image from the information encoded in the first area of the map image. A correspondence acquisition unit that acquires a correspondence relationship with the coordinate system, and a coordinate conversion unit that acquires region information indicating the existence range in the second coordinate system of the second region including the first region according to the correspondence relationship; There is provided an information display device comprising a display data acquisition unit that acquires display data according to region information.

  According to another aspect of the invention, from the information encoded in the first region of the map image, the first coordinate system on the map image and the display position of the display data arranged in the map image are defined. Correspondence acquisition step for acquiring a correspondence relationship with the second coordinate system, and coordinates for acquiring region information indicating the existence range of the second region including the first region in the second coordinate system according to the correspondence relationship An information display method including a conversion step and a display data acquisition step of acquiring display data according to region information is provided.

ADVANTAGE OF THE INVENTION According to this invention, the increase in the information content of the display data displayed with the image of the existing map can be aimed at.

It is a figure which illustrates the paper map in which the code was embedded. It is a figure which shows the example of the square area | region where the code was embedded. It is a figure which illustrates the outline | summary of a code embedding technique. It is a figure which illustrates the hardware constitutions of information equipment. It is a figure which shows the example of a data table. It is a figure which shows the data example of the database of display data. It is a figure which illustrates the flowchart of the process which image | photographs the map with which the code was embedded, and superimposes and displays the display data on the image of the photographed map. It is a figure which illustrates the detailed flowchart of a decoding process. It is a figure which shows the example of a response | compatibility of the rectangular corner coordinates and the latitude longitude information acquired through a network. It is a figure which shows the example of a response | compatibility of the four corner coordinates of a rectangle, and the four corner latitude and longitude acquired through a network. It is a figure which shows the example which displayed and superimposed the display data converted into the coordinate system of the picked-up image on the picked-up image. It is a figure which displays on the coordinate which converted the coordinate whose converted coordinate is in the range of a picked-up image among the icons for a display. It is a figure which illustrates the process outline | summary of the modification which determines an upper side. It is a figure which illustrates the positional information corresponding to the map image in which the latitude longitude information was embedded. It is a figure which illustrates the outline | summary of the procedure which embeds position information in a map image. It is a figure which illustrates the procedure which converts the detected binary code into the latitude / longitude information of the four corners of the rectangular area. It is a figure which illustrates the flowchart of the process which image | photographs the paper map with which data was embedded with the imaging device of information equipment, and superimposes additional information on a picked-up image, and displays it. It is a figure which illustrates the detailed flowchart of a decoding process.

  Hereinafter, an information device according to an embodiment will be described with reference to the drawings. The configuration of the following embodiment is an exemplification, and the present apparatus is not limited to the configuration of the embodiment.

  An information processing technique using an information device including a photographing device, such as a camera-equipped mobile phone, will be described as the information device of the first embodiment. In the first embodiment, the information device captures a map printed on a paper medium, a print medium, or the like printed on a paper medium, a printing medium, or the like by a photographing device, and acquires a map image. Here, the paper medium refers to a medium on which information is drawn so as to be readable on a paper surface. The paper medium includes, for example, a newspaper, a magazine, a book, an advertisement flyer, a poster, and the like printed on paper with ink, paint, or the like. A paper medium is also called a print medium. In addition to the advertisement flyer, the advertising medium includes an outdoor advertising billboard, an outdoor large display display, a television image advertisement, an image advertisement on the Internet web, and the like. In the case of a medium drawn on a billboard for outdoor advertising, it is desirable to draw the map with a drawing device that draws a paint on a flat medium and draws the map. Other media include broadcast media, information media provided by services on the Internet, and the like.

Furthermore, a code is embedded in the map image in the map of the first embodiment. The code embedded in the map image is information that uniquely identifies the area indicated by the map. The information device extracts a code from the map image by image processing of the captured map image. Then, the information device presents the code to a server connected through a network, for example. Then, the information device requests information to be added to the map from the server based on the presented code. The information added to the map is information related to the area identified by the code. For example, based on the code, the information device displays an icon indicating “a restaurant named A” as information to be added to the map superimposed on the captured image on the display.

  FIG. 1 is a diagram illustrating a paper map in which codes are embedded. In Example 1, it is assumed that the paper map is rectangular. The rectangular paper map is divided by a plurality of ruled lines L in the vertical and horizontal directions. The ruled line L corresponds to a ruled line pattern. A unique code is embedded in a rectangular area surrounded by vertical and horizontal ruled lines L. The unique code refers to a code that can distinguish between a rectangular area to which a code is attached and a rectangular area to which another code on the map is attached.

  FIG. 2 shows an example of a rectangular area SQ in which a code is embedded. As a data embedding method, for example, the technology described in Japanese Patent No. 3784781 can be used. FIG. 3 exemplifies an outline of the code embedding technique described in Japanese Patent No. 3784781. In the code embedding technique shown in FIG. 3, an image is divided into quadrangular areas called even blocks in the vertical and horizontal directions. Then, one direction is selected for the image. For example, consider the horizontal direction from left to right in FIG. Then, the image is divided into horizontal rows, and a set of two adjacent blocks is formed in the row of blocks in one row. For example, in FIG. 3, two blocks A and B in the upper right corner are illustrated. Such two adjacent blocks will be referred to as a pair block.

  Then, a bit of 0 or 1 is assigned to the pair block by making a difference between the feature amounts of adjacent pair blocks. The feature amount is, for example, an average density or gradation level of pixels included in the block, or a specific color of the pixels included in the block, for example, an average density of yellow. For example, when the feature amount of the block A is smaller than that of the block B, the bit of the pair block is defined as 0. Further, when the feature amount of the block A is larger than that of the block B, the bit of the pair block may be defined as 1.

  In the example of FIG. 3, since eight pair blocks (16 blocks) are included in one row, one row can represent a code for 8 bits. Therefore, 128 bits of code can be expressed in all lines (16 lines). However, the first embodiment is not limited to the 128-bit code. For example, the same 16-bit code may be repeated 8 times and embedded in the image of FIG. By embedding the same code a plurality of times, so-called error correction can be performed by majority vote. Of course, the number of blocks is not limited to 16 × 16. Also, an error detection code can be embedded in the information indicating the code.

  The direction in which the code is embedded can be, for example, the direction from the upper left to the lower right. That is, in the row direction from the left to the right in FIG. 3, the uppermost row may be defined as the first row and the lowermost row may be defined as the 16th row. Then, a bit may be defined for each pair block arranged from left to right for each row. Furthermore, the first line may be the start line and the 16th line may be the end line.

  The embedding direction may be a vertical direction from the upper right to the lower left. The rightmost column may be the first column and the leftmost column may be the sixteenth column. That is, the code may be embedded from the upper right to the lower left.

  The embedding direction may be a horizontal direction from the lower right to the upper left. The lowermost row may be the first row and the uppermost column may be the 16th row. That is, the code may be embedded from the lower right to the upper left.

  The embedding direction may be a vertical direction from the lower left to the upper right. The leftmost column may be the first column and the rightmost column may be the sixteenth column. That is, the code may be embedded from the lower left to the upper right.

The embedding direction can be defined by, for example, four values of dir = {0,1,2,3} for the parameter dir. dir = 0 means that the code is embedded so that it starts from the upper left of the rectangular area SQ delimited by the ruled lines in the captured image, and ends at the lower right by a group of pair blocks in the row direction from left to right Is the case.

dir = 1 specifies the code embedding direction obtained by rotating the code embedding direction of dir = 0 clockwise by 90 degrees. That is, dir = 1 starts from the upper right of the rectangular area SQ delimited by the ruled lines in the photographed image, and the code is embedded so as to end at the lower left by a pair of block blocks in the column direction from top to bottom. This is the case.

dir = 2 specifies the code embedding direction obtained by rotating the code embedding direction of dir = 0 clockwise by 180 degrees. That is, dir = 2 is a rectangular area S delimited by ruled lines in the captured image.
This is a case where a code is embedded so as to start from the lower right side of Q and end in the upper left side by a group in a pair block column in the row direction from right to left.

dir = 3 designates the code embedding direction obtained by rotating the code embedding direction of dir = 0 clockwise by 270 degrees. That is, dir = 3 is a quadrangular area SQ delimited by ruled lines in the captured image.
This is a case where the code is embedded so as to start at the upper right by the pair block group in the column direction from the lower left to the upper end. However, the information embedding direction is not limited to the above case. For example, dir = {0,1,2,3} may be defined in a direction that rotates counterclockwise as opposed to the above definition. dir = 0 does not have to start from the upper left.

  By the above method, the information device captures the paper map in which the code is embedded with the image capturing device of the information device and decodes the code. Furthermore, the information device acquires the latitude and longitude of the four corners of the quadrangular area SQ via the network based on the code. Hereinafter, the latitude and longitude of the four corners of the rectangular area SQ acquired via the network are referred to as latitude / longitude information. Furthermore, by determining the embedding direction, the information device associates the acquired latitude / longitude information with the four corner coordinates of the rectangular area. Here, the four corner coordinates of the quadrangular area are coordinates on the coordinate axes on the image captured by the information device.

For example, the embedding code on the map is an image in which the upper direction of the map is north with respect to east, west, north, and south on the map, and is embedded in the embedding direction of dir = 0. Furthermore, the latitude and longitude information acquired via the network is the image of the top left, the top right, the bottom right, and the bottom left when dir = 0 in the direction of embedding in the image with north as the reference on the map. Assume that latitude and longitude can be acquired.

Assuming such a definition, if the information device detects, for example, the embedding direction dir = 0, the information device uses the latitude and longitude acquired through the network as the upper left point, upper right point, lower right point, and lower left point. What is necessary is just to use as a latitude and a longitude. Whether or not the embedding direction dir = 0 has been detected can be determined by the information device attempting to decode the captured image in the embedding direction dir = 0 and succeeding in decoding. Whether or not the decoding has succeeded can be determined, for example, by whether or not an error has been detected and the decoding has been normally performed in the error detection of the information indicating the code. In addition to the code itself, a specific symbol, for example, a command or keyword such as “code =” may be embedded in the embedded information. Then, the information device may determine whether or not the information device has been successfully decoded by detecting a command or a keyword together with the code.

In addition, when the information device detects, for example, the embedding direction dir = 1, the information device rotates the latitude and longitude acquired through the network 90 counterclockwise to obtain an upper left point, an upper right point, a lower right point, and a lower left point. May be used as the latitude and longitude. The same applies to dir = 2 and dir = 3. In this sense, the embedding direction dir can also be called designation of a rotation angle.

FIG. 9 and FIG. 10 show examples of correspondence between the four corner coordinates of the quadrangular area and the latitude / longitude information acquired through the network based on the detection result of the embedding direction dir. The map on the right side of FIG. 9 indicates the position of latitude / longitude information registered in the server with numbers (1) to (4). The square area indicated by the numbers (1) to (4) can be said to be a coordinate system before conversion. The server on the network has latitude and longitude information corresponding to each position (1)-(4) in the coordinate system before conversion.

On the other hand, the map on the right side of FIG. 9 illustrates a captured map image. The information device detects a ruled line on the map image, and detects the vertices (1) to (4) of the quadrangular area surrounded by the four ruled lines. However, the square area detected on the map image includes distortion or rotation as compared with the position of the latitude / longitude information registered in the server. Therefore, the information device performs coordinate conversion between the latitude and longitude information acquired from the server on the network and the coordinates of the vertices of the rectangular area detected on the map image. Therefore, the coordinate system on the map image can also be referred to as a transformed coordinate system.

For example, if it is determined in the decoding process that the embedding direction dir = 0, (1 in FIG.
) To (4). In the case of the embedding direction dir = 1, (1) in FIG.
It becomes correspondence shown in (4).

  FIG. 4 illustrates a hardware configuration of the information device 10 as an image display device. The information device 10 includes a CPU 11, a first storage device 12, a second storage device 13, a display 14, an operation unit 15, a communication unit 16, a media access device 17, and a photographing device 18.

  The CPU 11 executes a computer program that is executed on the first storage device 12 and provides the functions of the information device 10. The CPU 11 is not limited to one and may include a plurality of cores.

  The first storage device 12 stores a computer program executed by the CPU 11, data processed by the CPU 11, and the like. As the first storage device 12, for example, a volatile memory such as a nonvolatile ROM (Read Only Memory) or a RAM (Random Access Memory) can be used. The RAM is, for example, DRAM (Dynamic RAM), SRAM (Static RAM), FeRAM (Ferroelectric RAM), MRAM (Magnetoresistive RAM) or the like. In addition, for example, DRAM and SRAM can be used together, and SRAM can be used as a cache memory.

  The second storage device 13 is, for example, a solid state drive (SSD) using a flash memory or the like. However, the second storage device 13 may be, for example, a hard disk driven by a hard disk drive. The second storage device 13 is nonvolatile and may be called an external storage device, for example. However, the second storage device 13 may be integrated with the first storage device 12. Further, the second storage device 13 and the first storage device 12 may be arranged in the same physical address space.

  The display 14 is, for example, a liquid crystal display or an electroluminescence panel. The display 14 is connected to the CPU 11 through the interface 14A. The interface 14A is, for example, a graphics module such as VGA (Video Graphics Array) or an interface such as DVI (Digital Visual Interface).

  The operation unit 15 is an input device such as a key layout, a mouse, a touch panel, and an electrostatic pad. The key layout is a sequence of push buttons. However, a keyboard may be connected as a key layout. The electrostatic pad is a device used to detect a user operation of tracing a flat pad with a finger or the like, and to control the position and movement state of the cursor on the display in accordance with the user operation. For example, the movement of the user's finger is detected by a change in the capacitance of the electrode under the flat pad.

The communication interface 16 is, for example, a wireless LAN (Local Area Network) interface. However, the communication interface 16 may be a communication unit with a mobile phone base station or a communication unit with a PHS (Personal Handy Phone System) base station. The communication interface 16 may be a connection interface to the LAN, that is, a network interface card (NIC). The information device 10 communicates with the server 20 on the network through the communication interface 16 to acquire various information.

  The media access device 17 is an input / output device such as a flash memory card, for example. However, the media access device 17 may be an interface to a CD (Compact Disc), DVD (Digital Versatile Disk), or Blu-ray Disc input / output device.

  The imaging device 18 is, for example, a CCD (Charge Coupled Device), a MOS (Metal Oxide Semiconductor) device, or the like. The imaging device 18 is connected to the information device 10 via the camera interface 18A. The camera interface 18A may be an external interface such as a USB (Universal Serial Bus). The camera interface 18A may be an interface unique to the manufacturer of the photographing apparatus 18. Further, when the photographing apparatus 18 is built in the information device 10, the camera interface 18 </ b> A may be any interface that can communicate with the CPU 10.

  Hereinafter, an example of data managed by the server 20 on the network will be described. FIG. 5 shows an example of a data table on the server 20. The data table stores latitude and longitude information at the four corners corresponding to the codes embedded in the map. Here, the four corners refer to the four corners of the quadrangular area SQ divided by the ruled lines shown in FIG. 2, that is, the quadrangular area SQ in which the code shown in FIG. 3 is embedded.

  In the first embodiment, the information device 10 detects the embedded code from the photographed image and transmits the code to the server 20. For example, when the detected code is 10001, latitude and longitude information (37.25, 137.25), (37.25, 138.5), (36.5, 137.25), (36.5, 138.5) are acquired. The server 20 returns the latitude / longitude information acquired based on the received code to the information device 10.

When the information device 10 receives the latitude / longitude information from the server 20, the information device 10 calculates the latitude and longitude of predetermined four vertices in the display area of the captured map image based on the latitude / longitude information. The display area refers to an area of an image displayed on the display. That is, the information device 10 calculates a conversion formula for converting the coordinate system of the captured map image into latitude and longitude from the relationship between the four corner coordinates of the quadrangular area SQ and the latitude and longitude information received from the server 20. Then, the information device 10 calculates the latitude and longitude corresponding to the four vertex coordinates of the display area of the captured map image, for example, the entire effective pixel area of the captured image. However, the display area of the map image is not limited to the rectangular area. For example, the display area of the map image may be a curved area with rounded corners. Further, it may be a circle, an ellipse, or a region including a curve. In short, the information device 10 acquires a conversion formula for converting the coordinate system of the captured map image into latitude and longitude, so that even if the display area of the map image before conversion has a shape other than a square, the captured map is displayed. The image coordinate system can be converted into latitude and longitude. Therefore, however, even when the display area of the map image is other than a quadrangle, four vertices included in the display area of the map image can be assumed. Therefore, hereinafter, the term “predetermined four vertices of the display area of the map image” is used. The “predetermined four vertices of the map image display area” may be considered, for example, as the four vertices set in advance by the information device 10 included in the map image display area.

  The information device 10 acquires data to be displayed in the display area (hereinafter, display data) from the server 20. Therefore, the information device 10 transmits the latitude and longitude corresponding to the four vertex coordinates of the display area to the server 20. The server 20 returns the display data included in the received latitude and longitude ranges to the information device 10.

  In the first embodiment, it is assumed that the server that acquires the display data is the same as the server 20 that acquired the latitude / longitude information of the rectangular area. However, the server that acquires the display data may be a server other than the server 20 that acquired the latitude / longitude information of the rectangular area. In the first embodiment, data indicating facilities on a map is assumed as display data.

  FIG. 6 shows a data example of the display data database. The display data database is, for example, in a table format. Each row of the table is one display data. In FIG. 6, reference numerals of data 101 to data 114 are given. Each of the data 101 to data 114 includes fields of business type, store name, latitude, longitude, and display icon.

  The industry type is the industry type of the facility represented by each display data. The store name is a unique name of the facility, for example, the name of the store. The latitude and longitude are positions on the map of the facility indicated by the display data. The display icon is a file name including data such as a picture or a character pattern when the facility is displayed on the map.

  FIG. 7 illustrates a flowchart of a process of photographing a map in which a code is embedded and displaying display data superimposed on the photographed map image. The CPU 11 of the information device 10 executes the process of FIG. 7 using a computer program that is developed on the memory so as to be executable. In the process of FIG. 7, the user instructs the start of the map reading process through the operation unit 15. When receiving the instruction to start the map reading process, the information device 10 acquires a photographed image photographed by the photographing device 18 via the camera interface 18A (S1). The information device 10 performs a decoding process on the acquired captured image (S2). Details of the decoding process will be described later with reference to FIG.

  Next, the information device 10 determines whether the decoding has succeeded (S3). If the decoding is successful, the information device 10 can detect three types of information: the four corner coordinates of the rectangular area in the captured image, the code embedded in the rectangular area, and the embedding direction. Note that the determination in S3 is a determination as to whether or not the decoding process in S2 has succeeded.

  If the decoding is successful, the information device 10 inquires of the server 20 about latitude and longitude information of the four corners of the quadrangular area from the detected code (S4). The CPU 11 of the information device 10 executes the process of S4 as a second acquisition unit. The latitude and longitude information at the four corners of the rectangular area corresponds to the second coordinate information indicating the reference position in the second coordinate system. The reference position can be considered as a coordinate serving as a reference for coordinate conversion. In the first embodiment, the correspondence for coordinate conversion is determined from the relationship between the four reference positions based on the latitude and longitude information and the four reference positions in the coordinate system of the captured image.

Next, the latitude and longitude of predetermined four corners of the photographed image are calculated based on the four corner coordinates of the rectangular area in the photographed image, the longitude and latitude information of the four corners, and the embedding direction (S5). The CPU 11 of the information device 10 performs the processes of S4 and S5 as a latitude / longitude information acquisition unit. The calculation of S5 is obtained by coordinate transformation by projective transformation. In the projective transformation of the first embodiment, the latitude / longitude information and the rectangular area are converted into the coordinates of the four points after the conversion, the four corner coordinates of the rectangular area detected by the decoding process are the coordinates of the four points before the conversion. Match the four corner coordinates. At this time, the correspondence of the four points is determined from the embedding direction obtained by the decoding process. The CPU 11 of the information device 10 performs the processing of S1-S4 as a correspondence acquisition unit.

  Now, the coordinates of the four points before conversion are (X1, Y1) (X2, Y2) (X3, Y3) (X4, Y4), and the coordinates after conversion are (x1, y1) (x2, y2) (x3, y3 ) (x4, y4), the simultaneous equations of the projective transformation are expressed as follows, and the transformation coefficients A to H can be obtained.

X1 * A + Y1 * B + C-x1 * X1 * G-x1 * Y1 * H = x1
X1 * D + Y1 * E + F-y1 * X1 * G-y1 * Y1 * H = y1
X2 * A + Y2 * B + C-x2 * X2 * G-x2 * Y2 * H = x2
X2 * D + Y2 * E + F-y2 * X2 * G-y2 * Y2 * H = y2
X3 * A + Y3 * B + C-x3 * X3 * G-x3 * Y3 * H = x3
X3 * D + Y3 * E + F-y3 * X3 * G-y3 * Y3 * H = y3
X4 * A + Y4 * B + C-x4 * X4 * G-x4 * Y4 * H = x4
X4 * D + Y4 * E + F-y4 * X4 * G-y4 * Y4 * H = y4
The information device 10 creates the following coordinate conversion formula using the values A to H obtained from the above. Then, the information device 10 converts the coordinates of the four corners of the display area in the captured image into latitude and longitude using the following coordinate conversion formula. Here, X and Y are the coordinate system of the captured image, and x and y are the latitude and longitude. The coordinate system of the captured image corresponds to the first coordinate system, and the latitude and longitude correspond to the second coordinate system.

x = (A * X + B * Y + C) / (G * X + H * Y + 1)
y = (D * X + E * Y + F) / (G * X + H * Y + 1)
For example, assume the following data: Four corner coordinates of the rectangular area in the captured image:
(X1, Y1) = (36, 61), (X2, Y2) = (220, 86), (X3, Y3) = (13, 191), (X4, Y4) = (201, 215);
Latitude and longitude of the four corner coordinates:
(x1, y1) = (37.25,137.25), (x2, y2) = (37.25,138.5), (x3, y3) = (36.5,137.25), (x4,
y4) = (36.5,138.5);
In this case, conversion coefficients A to H for converting the coordinate system of the photographed image into latitude and longitude are obtained as follows using the above simultaneous equations.

A = -0.0022589372, B = -0.00040533077, C = 37.5744860305, D = -0.0046212872, E = 0.0209821614, F = 136.9413073490, G = -0.0000817367, H = 0.0001443715
Further, the conversion formulas from the latitude / longitude (x, y) to the coordinate system (X, Y) of the captured image, and the conversion coefficients A ′ to H ′ are as follows.

X = (A '* x + B' * y + C ') / (G' * x + H '* y + 1)
Y = (D '* x + E' * y + F ') / (G' * x + H '* y + 1)
A '=-24.5936503114, B' =-118.3265988151, C '= 17127.8929059696, D' = 133.3829560990, E '=-16.4861005621, F' =-2754.1678566003, G '=-0.0212668996, H' =-0.0072915084
Using the conversion coefficients A to H, the latitude and longitude of predetermined four corner coordinates (0, 0), (240, 0), (0, 320), (240, 320) of the captured image are calculated as (37.57 , 136.94), (37.77, 138.55), (35.79, 137.31), (35.95, 138.86).

After obtaining the latitude and longitude of the predetermined four corners of the captured image, the information processing apparatus 10 acquires display data of a predetermined condition having latitude and longitude within the range of the four corners from the server (S6). The CPU 11 of the information device 10 performs the process of S6 as a display data acquisition unit. As described above, the server that acquires the display data may be the same as the server 20 that acquired the latitude / longitude information of the rectangular area, or may be another server.

  When the search condition for the display data is “A restaurant named A”, the search condition for the database in FIG. 6 is as follows.

“Industry = Restaurant” and “Store Name = A” and “Minimum Latitude at Four Corners 35.79 <= Latitude of Stores <= Maximum Latitude at Four Corners 37.77”
And “Minimum longitude of the four corners 136.94 <= Latitude of the store <= Maximum longitude of the four corners 138.86”;
There are four data 102, data 109, data 110, and data 112 in FIG. Therefore, the information device 10 acquires the latitude, longitude, and display icon data from the server.

  Next, the information device 10 determines whether display data has been acquired (S7).

  When the display data can be acquired, the information device 10 converts the latitude and the latitude into the coordinates of the captured image using the conversion formula and the conversion coefficients A ′ to H ′ (S8).

  The coordinates (X, Y) of the captured image obtained for the above four data are shown below. In the first embodiment, for example, the upper left point of the display area of the captured image is set as the origin.

Data 102 (X, Y) = (28, 188),
Data 109 (X, Y) = (-11, 130),
Data 110 (X, Y) = (197, 115),
Data 112 (X, Y) = (152, 284);
Since the latitude and longitude of the predetermined four corner coordinates of these captured images are all different, the retrieved data may include data outside the range of the captured image. When data outside the range of the photographed image is included, when the coordinates of the photographed image are converted to the coordinates of the photographed image, either X or Y becomes negative or X> 240, Y> 320. Applicable data is excluded from the display data. In this example, the X value of the data 109 is −11, which is outside the range of the photographed image, so the data 109 is excluded, and three pieces of data 102, 110, and 112 become display data. FIG. 11 shows an example in which the data 102, 110, and 112 converted into the coordinate system of the captured image are displayed superimposed on the captured image.

  Finally, as shown in FIG. 12, the information device 10 superimposes the captured image on the display 14 and displays the display icons on the converted coordinates that are within the range of the captured image. (S9). In FIG. 12, a camera-equipped mobile phone is assumed as the information device 10. That is, a map printed on paper is photographed, a code is obtained from the obtained map image, and an icon indicating a restaurant is superimposed on the photographed map image based on the obtained code.

  On the other hand, when the display data cannot be acquired, that is, when the display data does not exist in the display area in the captured image, the information device 10 displays the captured image without the display data.

FIG. 8 illustrates a detailed flow of the decoding process. The CPU 11 of the information device 10 executes the process shown in FIG. 8 using a computer program that is executed on the memory. The CPU 11 performs the process of FIG. 8 as a decoding unit.

  First, the four corner coordinates of the rectangular area surrounded by the ruled line in the photographed image are detected (S20). As a method for detecting the four corner coordinates, the Hough transform, which is a general ruled line detection method, is used to detect the four sides and obtain their intersections. The CPU 11 of the information device 10 executes the process of S20 as a ruled line recognition unit and a first acquisition unit. That is, the CPU 11 of the information device 10 detects four sides as a ruled line recognition unit. Furthermore, the CPU 11 of the information device 10 calculates the coordinates of the four corners that are the intersections of the four sides as the first acquisition unit. The coordinates of the four corners that are the intersections of the four sides correspond to the first coordinate information indicating the reference position in the first coordinate system.

  The Hough transform is known as a method for obtaining a straight line LM that passes through the most points among the N points of the XY coordinate system. For example, assume that the equation of the straight line LM is y = a * x + b. Here, * is a multiplication symbol. At this time, a plurality of relational expressions yi = ai * xi + bi passing through N points (xi, yi) i = 1, N of the XY coordinate system can be created. The relational expression yi = ai * xi + bi constitutes a plurality of straight line trajectories in the coordinate system (a, b). If N points (xi, yi) i = 1, N in the XY coordinate system are on a straight line (slope a0, Y intercept b0), the relational expression yi = ai * xi + bi is one point. A group of straight lines passing through (a0, b0). Therefore, by obtaining the point (a0, b0) through which the most straight lines pass in the (a, b) coordinate system, the largest number of N points (xi, yi) i = 1, N in the XY coordinate system. A straight line passing through can be obtained.

  Next, the information device 10 determines whether or not the four sides of the quadrangular region can be specified by the Hough transform and all the four corner coordinates are detected (S21). When all the four corner coordinates are detected, the information device 10 performs a decoding process when the four sides of the quadrangular region are set as the upper side of the embedded region in the order of the upper side, the right side, the lower side, and the left side (S22-S26). The CPU 11 of the information device 10 executes the processing of S22-26 as a bit acquisition unit.

  The decoding process is a process of determining whether the bit block is a bit 0 or a bit 1 based on the image feature amount for the paired blocks arranged in the upper side direction. In other words, the sequence of pair blocks adjacent to the upper side is traced in the same direction as the bit embedding, and the feature values may be compared between the blocks in the pair block. An array of pair blocks adjacent to the upper side corresponds to the first block group. Then, bit = 0 or bit = 1 may be determined according to the same definition as when the bit is embedded. For example, in the case of the image block shown in FIG. 3, 8-bit information is obtained for one row. Further, when the same code is repeatedly embedded several times, error correction may be performed by majority processing.

That is, the information device 10 first sets the initial value dir = 0 (S22). The information device 10 executes the following process until dir reaches 4 (S23-26). That is, when dir = 0, the decoding process is executed in the row direction from the upper left to the lower right and from the left to the right with reference to the image coordinate system. That is, in this case, the upper side in the captured image is set as the upper side of the image in which the code is embedded.

When dir = 1, the decoding process is executed in the direction rotated clockwise by 90 degrees. That is, the information device 10 executes the decoding process in the column direction from the top to the bottom, from the upper right to the lower left with reference to the image coordinate system. That is, in this case, the right side in the captured image is the upper side of the image in which the code is embedded.

When dir = 2, the decoding process is executed in the direction rotated clockwise by 180 degrees. In other words, the information device 10 executes the decoding process in the column direction from the lower right to the upper left with respect to the image coordinate system and from the right to the left. That is, in this case, the lower side in the captured image is
The top side of the image with the code embedded.

When dir = 3, the decoding process is executed in the direction rotated clockwise by 270 degrees. That is, the information device 10 executes the decoding process in the column direction from the lower left to the upper right with reference to the image coordinate system, from the lower to the upper. That is, in this case, the left side in the captured image is the upper side of the image in which the code is embedded.

Then, the information device 10 determines whether or not the decoding is successful (S25). Whether decoding has succeeded or not is, for example, that no error was detected by the error detection code of the decoded information, that the decoded information contained a predetermined command or keyword, or that The latitude and longitude can be determined based on a specific range, for example, the latitude and longitude range of Japan, or a range of 0 to 360 degrees. If the decoding is not successful, the information device 10 returns the control to S23. If the decoding is successful, the information device 10 records the detected code, four corner coordinates, and the embedding direction (S27). If the four corner coordinates cannot be detected (NO in S21), or if the decoding is not successful from any direction (NO in S23), the decoding is failed (S28). And the information equipment 10 advances control to determination of S3 of FIG. That is, if the decoding is successful in the trial in the embedding direction of dir = {0,1,2,3} by repeating the processing of S23 to S26, the decoding is successful in S3 of FIG. . On the other hand, if the decoding is not successful in any embedding direction of dir = {0, 1, 2, 3} by repeating the processing of S23 to S26, the decoding fails in S3 of FIG.

  As described above, the information device 10 according to the first embodiment acquires the code embedded in the map image captured by the imaging device 18 and acquires the latitude / longitude information corresponding to the code from the server 20 on the network. Then, the information device 10 creates a conversion formula between the coordinate system of the map image, the latitude, and the longitude from the relationship between the four corner coordinates of the rectangular area in which the code is embedded and the latitude / longitude information. Then, the information device 10 acquires facility display data included in the display area of the map image from the server 20 on the network, and displays it superimposed on the captured map image.

  Therefore, the information device 10 does not have to download map data from the server 20 on the network, and the amount of communication data can be reduced. In addition, since the information device 10 captures an image of a map given as paper data, even when the display size of the display 14 is small, the information device 10 can be combined with a map whose paper size is larger than the display size of the display 14 to Usability can be improved. For example, when a large range map is displayed in a magazine, a pamphlet, a signboard, etc., and a part of the map is photographed by the photographing device 18, it indicates which range of the whole map the part of the photographed map is. It becomes easier for the user to recognize.

  Further, since the display data acquired from the server 20 on the network is superimposed on the map image obtained by photographing the existing map, the possibility that the latest data can be acquired as the display data is increased. For example, the user can superimpose and display information on facilities installed after the map is printed, buildings constructed, and the like.

  Furthermore, by projecting the coordinates for the captured image and displaying the data, the camera was tilted when shooting the map with the camera, and the vertical and horizontal directions of the image and the ruled line direction on the map were tilted. Even in this case, the display position can be corrected.

Further, in the first embodiment, the information device 10 recognizes the ruled line of the map image, and extracts a quadrangular region surrounded by four ruled lines. Therefore, even when the user is not aware of a specific area and takes a map roughly, the information device 10 can acquire additional information to be superimposed on the taken map, which is convenient for the user. Further, in the process of FIG. 8 described above, the decoding process is repeated for each of dir = {0, 1, 2, 3} sequentially until the decoding is successful. Therefore, even when the image by the imaging device 18 is rotated in units of 90 degrees, the information device 10 can increase the possibility of acquiring latitude / longitude information.

  Further, when a plurality of quadrangular areas are included on the photographed map, the decoding process may be executed for each quadrangular area. Then, when decoding is successful for the first time, the decoding process in the remaining rectangular area may be stopped. However, the projective transformation coefficient may be determined based on the vertex coordinates of a plurality of rectangular regions. By reflecting the vertex coordinates of a plurality of quadrangular regions, it is possible to improve the conversion accuracy of the projective transformation.

  Furthermore, in the first embodiment, a code is embedded in a map, and the information device 10 inquires the server 20 about latitude / longitude information based on the decoded code. Therefore, information embedded in the map itself can be simplified. For example, a rectangular area on a map in which a code is embedded and a code that can be uniquely identified are determined, and a map in which the code is embedded may be created. And how to use the code | cord | chord should just be determined by the application program of the information equipment 10 and the server 20 in the step after a map is produced. That is, with the configuration of the first embodiment, it is possible to create a map in which a code is embedded very easily and at an early stage, and gradually improve and enhance the service.

<Modification>
In the first embodiment, the processing has been described assuming that dir = {0,1,2,3}. For example, when the ruled line detected in the image coordinate system is tilted, the upper side is determined from the distance between the four vertices of the rectangle having sides in the coordinate axis direction including the four vertices of the quadrangular area divided by the ruled line. do it.

FIG. 13 illustrates an outline of processing for determining the upper side. For example, it is assumed that the ruled line obtained by the Hough transform is inclined like L1, L2, L3, and L4 in the coordinate system of the captured image. In this case, the information device 10 creates rectangles PUL, PUR, PDR, and PDL (dotted rectangles) that include a rectangular region surrounded by the ruled lines L1-L4. Then, the division device 10 sets the vertex P1 closest to the upper left point PUL of the rectangle that includes the quadrangular area surrounded by the ruled lines L1-L4 as the upper left point of the quadrangular area surrounded by the ruled lines L1-L4. When dir = 0, the information device 10 determines the vertex P1 and the next vertex P2 in the clockwise direction with respect to the vertex P1. And the information apparatus 10 should just perform a decoding process by making the edge | side L2 which has the vertices P1 and P2 into both ends into the upper side of the image where the code was embedded.

When dir = 1, the information device 10 determines the vertex P2 and the next vertex P3. And the information apparatus 10 should just perform a decoding process by making the edge | side L3 which uses the vertices P2 and P3 as both ends into the upper side of the image in which the code was embedded. When dir = 2, the information device 10 determines the vertex P3 and the next vertex P4. And the information apparatus 10 should just perform a decoding process by making the edge | side L3 which makes the vertex P3 and P4 both ends into the upper side of the image in which the code was embedded. When dir = 3, the information device 10 determines the vertex P4 and the next vertex P1. The information device 10 may perform the decoding process with the side L1 having the vertices P4 and P1 at both ends as the upper side of the image in which the code is embedded.

  Note that before the decoding process, the coordinate transformation may be performed once so that L1 to L4 are parallel to the coordinate axis of the captured image (or the rectangular side of the dotted line in FIG. 13). For example, the decoding process may be performed after coordinate conversion so that the side L2 is parallel to the upper side LU of the dotted rectangle. Then, after the embedded code is determined, a conversion formula between the coordinates of the apexes P1-P4 of the inclined quadrangular area L1-L4 and the latitude / longitude information may be created.

  A second embodiment will be described with reference to FIGS. In the first embodiment, the information device 10 acquires the latitude / longitude information from the server 20 after obtaining the code embedded in the map image. In the second embodiment, processing using a map in which latitude and longitude information is embedded will be described. That is, the information device 10 captures a map with the imaging device 18 and generates a map image. Then, the information device 10 reads latitude / longitude information from the generated map image. The information device 10 acquires display data from the server 20 on the network based on the read latitude / longitude information. Then, for example, the information device 10 acquires an icon indicating “a restaurant named A” as additional information. The information device 10 then superimposes the captured image on the display 14 and displays additional information.

FIG. 14 is a diagram illustrating position information corresponding to a map image in which latitude / longitude information is embedded. If the map image is latitude x and longitude y,
Upper left corner (x1, y1) = (37.25,137.25),
Upper right corner (x2, y2) = (37.25,138.5),
Lower left corner (x3, y3) = (36.5,137.25),
Lower right corner (x4, y4) = (36.5,138.5);
It is. Therefore, the information device 10 is a map in a range of latitude -0.75 and longitude +1.25 with the upper left corner of the four corners as a reference.

  FIG. 15 illustrates an outline of a procedure for embedding position information in a map image. As shown in FIG. 15, the information device 10 converts the latitude and longitude corresponding to the four corner coordinates into a binary embedded code.

  The information device 10 first converts the latitude and longitude at the upper left corner of the four corners into a 5-digit decimal number, and further converts the 5-digit decimal number obtained by the conversion into a 17-digit binary number. The information device 10 converts the latitude range from the upper left corner of the four corners to the lower left corner of the four corners into signed three-digit decimal data. Further, the information device 10 converts the converted decimal data into binary data having a code part of 1 digit and a data part of 11 digits.

  Furthermore, the information device 10 converts the longitude range from the upper left corner of the four corners to the upper right corner of the four corners into signed 3-digit decimal data. Then, the information device 10 converts the converted decimal number into binary data having a code part of 1 digit and a data part of 11 digits. By the above procedure, the upper left latitude part of the four corners. An embedding code of binary 56 digits having a four corner upper left longitude part, a latitude range part, and a longitude range part is created. In order to perform error correction by majority processing for 56 binary digits, the number of embedded bits in an image is 168 bits. Therefore, for example, a block configuration in which data of 20 × 20 blocks and 200 bits can be embedded may be employed. Further, the number of blocks may be increased so that error correction by majority vote can be executed with more information.

  The created embedding code is embedded in an image, for example, by the method described in Japanese Patent No. 3784781 shown in FIG. That is, the information device 10 embeds the image in the image by assigning 0 or 1 bits to the pair blocks by dividing the image into blocks and making a difference in the feature values of the adjacent pair blocks as shown in FIG. For example, as described in Japanese Patent No. 3784781, there is a feature that even if the yellow density is changed from the yellow density in the original image, it is difficult for human eyes to feel. Therefore, for example, the code is embedded in the map image by changing the yellow shade of the pair block corresponding to the bit pattern.

  FIG. 16 illustrates a procedure for converting the detected binary code into latitude and longitude information at the four corners of the quadrangular area. The information device 10 first converts the upper 17 digits of the binary code into a 5-digit decimal number. Then, the information device 10 obtains the latitude of the upper left corner of the quadrangular area by lowering the decimal point of the obtained decimal number by two digits.

  Similarly, the information device 10 converts the next 17 digits of the binary code into a 5-digit decimal number. Then, the information device 10 obtains the longitude at the upper left corner of the four corners of the quadrangular area by lowering the decimal point by two digits.

  Further, the information device 10 divides the next 12 digits of the binary code into 1 digit code portion +11 digits, and converts the code portion to 0 if the code portion is 0 and to + if it is 1. The information device 10 converts the 11-digit portion into a 3-digit decimal number. Further, the information device 10 obtains a latitude range from the upper left corner of the quadrangular area to the lower left corner of the quadrangular area by lowering the decimal point of the obtained decimal number by two digits.

Similarly, the information device 10 divides the next 12 digits of the binary code into a code of 1 digit +11 digits, converts the code part to 0 if the code part is 0, and converts it to + if the code part is 1, and 3 digits for the 11 digit part. Is converted to a decimal number. The information device 10 obtains a longitude range from the upper left corner of the quadrangular area to the lower right corner of the quadrangular area by lowering the decimal point of the obtained decimal number by two digits. With the above processing, if the upper left latitude and longitude of the four corners are x1 and y1, (x1, y1) = (37.25, 137.25), the latitude range -0.75 and the longitude range +1.25 are acquired. Based on this, the remaining latitude and longitude of the four corners of the quadrangular area are obtained by the following equation.
Four corners upper right latitude and longitude (x2, y2) = (x1, y1 + longitude range) = (37.25,138.5);
Four corners lower left latitude longitude (x3, y3) = (x1 + latitude range, y1) = (36.5,137.25);
Four corners lower right latitude and longitude (x4, y4) = (x1 + latitude range, y1 + longitude range) = (36.5,138.5);
When dir = 0, the upper left corner of the detected area in the captured image is assigned to the upper left corner of the rectangular area. When dir = 1, the upper right corners of the detected areas in the captured image are assigned to the upper left corners of the quadrangular areas. When dir = 2, the lower right corner of the detected area in the captured image is assigned to the upper left corner of the quadrangular area. In the case of dir = 3, the lower left corner of the detected area in the captured image is assigned to the upper left corner of the rectangular area.

  FIG. 17 illustrates a flowchart in which a paper map in which data is embedded is photographed by the photographing device 18 of the information device 10 and additional information is superimposed on the photographed image and displayed. In the process of FIG. 17, the same processes as those in FIG.

  First, the information device 10 starts reading a map in response to a user instruction, as in the first embodiment. By the map reading process, a camera photographed image obtained by photographing a paper map is acquired via the camera interface 18A (S1). A decoding process is executed on the acquired captured image (S2A). The CPU 11 of the information device 10 performs the processing of S1-S2A as a correspondence acquisition unit.

  If the decoding is successful (YES in S3), the CPU 11 of the information device 10 calculates the latitude and longitude information of the four corners of the captured image as in the first embodiment ( S5A). That is, in the embodiment, the latitude and longitude are obtained from the information embedded in the map image, and projective transformation is executed. Therefore, in the second embodiment, the information device 10 does not have to acquire the latitude / longitude information of the four corners of the quadrangular area from the server 20. The CPU 11 of the information device 10 performs the process of S5A as a coordinate conversion unit. Since the processes after S6 are the same as those in FIG. 8, the description thereof is omitted.

FIG. 18 illustrates a detailed flowchart of the decoding process (S2A in FIG. 17). Note that the processing of S20 to S26 is a process of decoding embedded information from an image, and the basic procedure is the same as in the case of FIG. However, in the case of FIG. 8, the embedded information in the image is a code for identifying the region, whereas in FIG. 18, the embedded information in the image is latitude / longitude information (FIG. 15, The difference is that (see FIG. 16). The CPU 11 of the information device 10
The processing shown in FIG. 18 is executed by a computer program that is executably expanded on the memory. The CPU 11 performs the process of FIG. 18 as a decoding unit.

First, the information device 10 detects the four corner coordinates of the quadrangular region surrounded by the ruled line in the captured image (S20). The four corner coordinates of the rectangular area correspond to first coordinate information indicating a reference position in the first coordinate system. When all the four corner coordinates are detected (YES in S21), the decoding process is performed by the method of Japanese Patent No. 3784781 for the case where the four sides of the quadrangular region are the upper side, the right side, the lower side, and the left side in this order. It performs (S23-S26).

  If the decoding is successful (YES in S26), the detected binary code is converted into latitude / longitude information of the four corners of the rectangular area (S27A). Whether or not the decoding is successful is determined in the same manner as in the case of FIG. If the four corner coordinates cannot be detected, or if the decoding cannot be successful from any direction, the information device 10 determines that the decoding has failed. Note that the latitude and longitude information at the four corners of the quadrangular region corresponds to the second coordinate information indicating the reference position in the second coordinate system.

  If the decoding is successful (YES in S3 of FIG. 17), the information device 10 advances the control to S5A of FIG. 17, and obtains the four corner coordinates of the rectangular area in the captured image, the latitude and longitude information of the four corners, and the rotation angle. In addition, the latitude and longitude of the four corners of the captured image are calculated.

  As described above, according to the processing of the second embodiment, since the latitude and longitude of the four corners of the quadrangular area are embedded in the captured image, the information device 10 does not need to query the server 20 for the latitude and longitude. The latitude and longitude of the display area of the captured map image can be calculated.

  As described above, one aspect of the disclosed technology relates to an image display technology related to a map. That is, the information device 10 determines whether the coordinate system of the image and the latitude and longitude are based on the correspondence between the coordinates of the rectangular area surrounded by the ruled line corresponding to the coordinate information of the first area of the map and the latitude and longitude information. Create a coordinate transformation formula. Then, the information device 10 acquires latitude and longitude information of the display area of the map image corresponding to the second area including the first area. Further, the information device 10 acquires display data to be displayed superimposed on the map image from the latitude / longitude information of the acquired display area of the map image, and increases the amount of information about the information displayed on the captured map. Plan.

<< Other modifications >>
In Example 1 and Example 2, latitude and longitude were used as the second coordinate system. However, the second coordinate system may be defined by a coordinate system other than latitude and longitude. That is, in the display data database (see FIG. 6), the location of the facility corresponding to each display data may be represented by another coordinate system instead of the latitude and longitude. In short, when the information device 10 accesses the display data database, it is only necessary to be able to recognize in which coordinate system the position of the facility indicated by the display data is defined. Therefore, a common coordinate system may be used as the second coordinate system between the computer program for executing the processing of FIG. 7 or FIG. 17 and the display data database in the information device 10. For this purpose, the coordinate system of the display data database may be determined in advance. Then, the coordinates of the four vertices of the quadrangle in the coordinate system of the display data may be acquired by the procedure of the first embodiment or the procedure of the second embodiment. In that case, the maximum value or the minimum value in the coordinate system of the display data may be transferred from the server 20 to the information device 10 and used for determining whether or not the decoding result is correct. However, in the system in which the information device 10 acquires display data from a plurality of servers by using the latitude and longitude, there is an advantage that display data can be created for general use.

The processing described above applies to various types of maps such as paper media, print media, maps on signboards made of paint outdoors, maps displayed on large displays, and maps displayed on websites on the Internet. Can be applied.

<Computer-readable recording medium>
A program for causing a computer or other machine or device (hereinafter, a computer or the like) to realize any of the above functions can be recorded on a recording medium that can be read by the computer or the like. The function can be provided by causing a computer or the like to read and execute the program of the recording medium.

  Here, a computer-readable recording medium is a recording medium that stores information such as data and programs by electrical, magnetic, optical, mechanical, or chemical action and can be read from a computer or the like. Say. Examples of such a recording medium that can be removed from a computer or the like include a flexible disk, a magneto-optical disk, a CD-ROM, a CD-R / W, a DVD, a Blu-ray disk, a DAT, an 8 mm tape, a flash memory, and the like. There are cards. In addition, as a recording medium fixed to a computer or the like, there are a hard disk, a ROM (read only memory), and the like.

10 Information equipment
11 CPU
12 First Storage Device 13 Second Storage Device 14 Display 15 Operation Unit 16 Communication Interface 17 Media Access Device 18 Imaging Device 20 Server

Claims (8)

Correspondence between a first coordinate system on the map image and a second coordinate system that defines a display position of display data to be arranged on the map image from information encoded in the first area of the map image A correspondence acquisition unit for acquiring
In accordance with the correspondence relationship, a coordinate conversion unit that acquires area information indicating the existence range of the second area including the first area in the second coordinate system;
An image display device comprising: a display data acquisition unit that acquires display data according to the region information. The correspondence acquisition unit acquires a code embedded in the first area from the encoded information;
A first acquisition unit that acquires first coordinate information indicating a reference position of the first region in the first coordinate system;
The image display apparatus according to claim 1, further comprising: a second acquisition unit that acquires second coordinate information indicating a reference position of the first region in the second coordinate system according to the code. The correspondence acquisition unit includes a first acquisition unit configured to acquire first coordinate information indicating a reference position of the first region in the first coordinate system;
The image display apparatus according to claim 1, further comprising: a decoding unit that acquires second coordinate information indicating a reference position of the first region in the second coordinate system from the encoded information. The decoding unit
A ruled line recognition unit that recognizes a ruled line pattern in the image information of the map;
A bit acquisition unit that acquires a bit pattern embedded in accordance with a relationship of image feature amounts between blocks obtained by dividing a quadrangular region surrounded by four ruled lines recognized by the ruled line recognition unit. Item 4. The image display device according to Item 2 or 3.   The bit acquisition unit is a first block group that is an array of blocks adjacent to the selected side when any side of the quadrangular area is selected from among the blocks included in the quadrangular area. From the block group parallel to the first block group by repeating the process of processing the second block group adjacent to the first block group after the processing of the first block group. Trying to obtain the embedded bit pattern, ending the process if the trial is successful, and selecting an unselected side of the sides of the rectangular area if the trial is not successful The image display device according to claim 4, wherein the trial is repeated, and when the trial is not successful with any side of the quadrangular region as a reference, it is determined that the processing is impossible.   The image display device according to claim 2, wherein the second acquisition unit accesses a server on a network based on the code and acquires second coordinate information of the first region corresponding to the code. A first coordinate system on the map image and a second coordinate system for defining a display position of display data to be arranged on the map image from information encoded in the first region of the map image; A correspondence acquisition step for acquiring the correspondence of
In accordance with the correspondence relationship, a coordinate conversion step of acquiring area information indicating an existence range of the second area including the first area in the second coordinate system;
A display data acquisition step of acquiring display data according to the region information. A first coordinate system on the map image and a second coordinate system defining a display position of display data to be arranged on the map image from information encoded in the first area of the map image; A correspondence acquisition step for acquiring the correspondence of
In accordance with the correspondence relationship, a coordinate conversion step of acquiring area information indicating an existence range of the second area including the first area in the second coordinate system;
An image display program for executing a display data acquisition step of acquiring display data according to the region information.

Images