JP2007135078A - Data communication apparatus, data communication method, and data communication program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a data communication apparatus, a data communication method, and a data communication program which enable metadata to be buried in an arbitrary position of video. <P>SOLUTION: Metadata and coordinate data associated with each other are input to a flashing signal generation part 20. A pattern setting part 22 sets a flashing pattern relating to light emitting elements 111 or the like flashed in order to display metadata in an area on the display screen 110 of an image display device 100, which is specified by coordinate data, and a flashing speed. An output part 25 inputs a flashing signal including the flashing pattern to the image display device 100. The flashing pattern based on the flashing signal is displayed on the image display device 100 together with a video based on a video signal generated by a video signal generation part 10. This video is read by a camera or a photodetector, and when the flashing pattern of each area included in the image is decoded, metadata of each area can be extracted from the image. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a data communication device, a data communication method, and a data communication program for embedding metadata together with video in an image display device.

  Digital watermarking is a technology that embeds information in images or sound such as still images and moving images. When digital data is acquired by capturing or collecting digital watermarked images or sound, images and sound are captured from this digital data. The metadata embedded in the voice can be extracted (see, for example, Patent Document 1, Non-Patent Documents 1 and 2). Here, the metadata is information related to video displayed on an image display device or the like. In recent years, techniques for providing various functions and services based on metadata extracted from images and sounds have been proposed.

  For example, an image information providing service that embeds bibliographic information of an image or information related to the image as metadata in the image, connection to an image related Internet site that embeds URL (Uniform Resource Locators) related to the image as metadata An image identification service or an image information providing service (for example, see Patent Document 2) by embedding an image identifier such as a service or content ID has been proposed. These services are mainly targeted at papers such as magazines and posters. Since the image can be stably read by a digital camera, a digital video camera, a scanner, a copier, or the like on the paper surface, the metadata embedded in the image can be easily taken out. However, on paper, it has little impact on physical limitations and human vision, so its appeal is weak as a medium for providing information to many people. Therefore, it is desired to display an image in which an electronic watermark is embedded in an information providing medium (for example, see Non-Patent Document 3) that has a high appealing power to a large number of people, such as a large image display device on the street. A conventional large screen image display device and a data communication device for inputting a video signal to the image display device are shown in FIGS.

  As shown in FIG. 10, the large-sized image display device 100 includes a display screen 110 in which light emitting elements 111 such as LEDs that emit light in any one of red, blue, and green are arranged in a matrix. Such a large-sized image display device 100 performs advertisement display and image information provision similar to a poster indoors and outdoors such as a building wall surface, and can display not only still images but also moving images.

  As shown in FIG. 11, the data communication apparatus 200 includes a decoder 120 including a decoder 121 and a video memory 122, and a DA converter 130. In such a signal processing device 200, image data composed of digital data displayed on the display screen 110 of the image display device 100 is decoded by the decoder 120, converted into a video signal by the DA converter 130, and then the image display device. 100 is input. The image display apparatus 100 displays an image on the display screen 110 by causing the light emitting element 111 to emit light in accordance with the input video signal.

  By displaying an image with a digital watermark on such a large image display device, it becomes possible to provide various services with high appeal. However, with the conventional digital watermark technology, the resolution of the screen display device and Due to display and reading environment problems such as contrast and the distance between the screen display device and the observer, it has been difficult to stably read an image from the image display device. Thus, in recent years, a technique has been proposed that enables stable image reading regardless of the display and reading environment (see, for example, Patent Document 3 and Non-Patent Document 4). This is an application technology of optical communication using visible light, in which metadata to be embedded in an image is encoded as blinking light, and the display element of the image display device blinks in a pattern in which metadata is encoded during image display. Thus, metadata is displayed simultaneously with the image. Such a data communication apparatus is shown in FIG.

  As illustrated in FIG. 12, the data communication apparatus 300 includes a video signal generation unit 310, a blinking signal generation unit 320, and a synthesis unit 330. The video signal generation unit 310 has a configuration equivalent to that of the data communication apparatus 200 described with reference to FIG. 11 and generates a video signal based on image data displayed on the image display apparatus 100. The blinking signal generation unit 320 generates a blinking signal based on the metadata displayed on the image display device 100. The combining unit 330 combines the video signal generated by the video signal generation unit 310 and the blinking signal generated by the blinking signal generation unit 320 to generate a combined signal, and inputs the combined signal to the screen display device 100. As an example, assuming that the luminance change of the video signal corresponding to an arbitrary light emitting element 111 is FIG. 13A and the luminance change of the blinking signal is FIG. 13B, the combining unit 330 combines them to generate FIG. A composite signal of luminance change as shown in c) is generated. By inputting such a composite signal to the image display device 100, a video in which metadata is embedded is displayed on the display screen 110. By reading the video displayed on the display screen 110 with a camera or a light receiver and decoding the blinking signal included in the video, metadata can be extracted from the video.

  In general, the frame rate of a large image display device is, for example, about 1/30 seconds, and lighting control of the light emitting element 111 is performed at a relatively low speed. On the other hand, in optical communication such as IrDA (Infrared Data Association), lighting control of the light emitting element 111 is performed at a frequency much higher than a frame rate of, for example, about several MHz. Therefore, in the image display apparatus 100, blinking display for optical communication different from the video can be performed within the time for displaying the video for one frame. As a result, it is possible to display an image and metadata simultaneously and independently on one image display device 100.

Japanese Patent No. 3354880 Japanese Patent No. 3383793 JP 2004-72365 A Irie, Fujii, Sakamoto, “Application of Content ID Using Digital Watermark”, Information Processing Society of Japan, Electronic Intellectual Property Office / Social Infrastructure Research Group, 2000-EIP-109, p. 7-14 Nakamura, Katayama, Miyaji, Yamashita, Yamamuro, “Digital watermark detection method for service mediation system using mobile phone with camera”, Information Processing Society of Japan, Information Science and Technology Forum 2003, p. 409-410 Mitsubishi Electric Corporation, “Aurora Vision”, [online], [October 27, 2005 search], Internet, <URL: http://www.mitsubishielectric.co.jp/visual/aurora/index_b.html> Ohmae, Kazaura, Matsumoto, Sato, et al., “A Study on Circuit Design for Full Optical Access Wireless System”, Proceedings of the 33rd Annual Conference of the Institute of Image Electronics Engineers of Japan, p. 191,192

  However, in the conventional method, metadata is embedded in the entire video, and it has not been possible to embed metadata only in a predetermined area of the video.

  Accordingly, the present invention has been made to solve the above-described problems, and provides a data communication device, a data communication method, and a data communication program capable of embedding metadata in an arbitrary place of a video. With the goal.

  In order to solve the above-described problems, a data communication apparatus according to the present invention is a data communication apparatus that transmits communication data from a specific area of a display screen, and is associated with the communication data and the communication data. An acquisition means for acquiring a plurality of area information and a transmission means for transmitting communication data from the area on the display screen specified by the area information are provided.

  In the data communication apparatus, the transmission means may transmit the communication data in order.

  In the data communication apparatus, the grouping means for grouping the communication data for each communication data in which the areas are not adjacent to each other based on the area information, and the transmitting means are configured to transmit the communication data for each group at a predetermined time interval. It may be. Here, the grouping means may perform grouping every time the area information changes.

  The data communication apparatus may further include duration setting means for setting a duration for continuously transmitting the communication data according to the data amount of the communication data. Moreover, you may make it further provide the continuous time setting means which sets continuous time based on communication data with the largest data amount among the communication data contained in a group.

  The data communication apparatus may further include image display means for displaying an image on the display screen, and the transmitting means may transmit the communication data superimposed on the image by a blinking pattern using visible light.

  The data communication method according to the present invention is a data communication method for transmitting communication data from a specific area of a display screen, and obtains a plurality of communication data and area information associated with the communication data. And a transmission step for transmitting the communication data from the area on the display screen specified by the area information.

  A data communication program according to the present invention is a data communication program of a data communication apparatus for transmitting communication data from a specific area of a display screen, and the computer transmits communication data and area information associated with the communication data. And a transmission step for transmitting communication data from an area on the display screen specified by the area information.

  According to the present invention, a plurality of communication data can be specified by the area information and transmitted from the area on the display screen, respectively, so that the plurality of communication data can be transmitted without interfering with each other.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the data communication apparatus 1 according to the present embodiment. In the present embodiment, components equivalent to those described in the background art column are given the same names and reference numerals, and description thereof will be omitted as appropriate.

  The data communication apparatus 1 includes a video signal generation unit 10 and a blinking signal generation unit 20. Such a data communication device 1 detects an input of information from the outside such as an arithmetic device such as a CPU, a storage device such as a memory or an HDD (Hard Disc Drive), and a keyboard, a mouse, a pointing device, a button, or a touch panel. An input device, an I / F device that transmits and receives various information via a communication line such as the Internet, LAN (Local Area Network), WAN (Wide Area Network), etc., CRT (Cathode Ray Tube), LCD (Liquid Crystal Display) ) Or FED (Field Emission Display), etc., and a program installed in the computer. That is, the hardware device and software cooperate to control the above hardware resources by a program, thereby realizing the video signal generation unit 10 and the blinking signal generation unit 20 described above. Note that the program may be provided in a state of being recorded on a recording medium such as a flexible disk, a CD-ROM, a DVD-ROM, or a memory card.

  The video signal generation unit 10 has a configuration equivalent to that of the data communication apparatus 200 described with reference to FIG. 11, decodes image data input from the outside to generate a video signal, and generates the video signal. An arithmetic processing unit that inputs a signal to the image display apparatus 100. Thereby, a video based on the image data is displayed on the image display device 100. Here, the image data means moving image data or still image data encoded by a known encoding method such as MPEG (Moving Picture Experts Group) or JPEG (Joint Photographic Expert Group). The image data may be an analog signal of a television broadcast such as NTSC (National Television System Committee). In this case, the video signal generation unit 10 may be a known analog device that generates a video signal based on the analog signal.

  The blinking signal generation unit 20 is an arithmetic processing unit that generates a blinking signal from metadata and coordinate data input from the outside and inputs them to the image display device 100. Such a blinking signal generation unit 20 includes a reception unit 21, a pattern setting unit 22, an order setting unit 23, a duration setting unit 24, and an output unit 25. Here, the metadata is composed of digital data embedded in a video displayed on the image display device 100. The coordinate data is information regarding the position on the image display device 100 in which metadata is embedded, and designates an area on the display screen 110 of the image display device 100 as shown in FIG. In the example of FIG. 2, the area on the display screen 110 is divided into four areas 1 to 4, and each area is specified by coordinate data. The coordinate data is represented by a coordinate value representing a position on the display screen 110, a vector expression, or the like. Different areas on the display screen 110 specified by such coordinate data are associated with different metadata.

  The receiving unit 21 is an interface unit that receives metadata and coordinate data from a known communication line such as the Internet, WAN, or LAN, or a known recording medium such as a CD, DVD, or video tape. The metadata and coordinate data received by the receiving unit 21 are sent to the pattern setting unit 22, the order setting unit 23, and the continuation signal setting unit 24. The receiving unit 21 may include storage means such as a buffer memory and store the received metadata and coordinate data. As a result, when metadata and coordinate data are received via a communication line such as the Internet, it is possible to cope with communication failures such as congestion.

  The pattern setting unit 22 receives the input metadata in a region on the display screen 110 of the image display device 100 specified by the coordinate data, a camera that reads the metadata from the video displayed on the image display device 100, or a light receiving device. This is an arithmetic processing unit that performs an operation for setting a flashing pattern related to a flashing light emitting element 111 and a flashing speed in order to display a readable display on a device. Note that in this embodiment mode, blinking not only means turning on or off the light-emitting element 111 but also increasing or decreasing the luminance of the light-emitting element 111, or includes the light-emitting element 111 or a plurality of light-emitting elements 111. It also means that the wavelength of the pixel to be changed is changed.

  The order setting unit 23 is an arithmetic processing unit that generates an order signal related to the order of blinking the metadata of each region.

  The duration setting unit 24 is an arithmetic processing unit that generates a continuation signal relating to a time for continuously displaying metadata.

  The output unit 25 generates a blinking signal based on the blinking pattern generated by the pattern setting unit 22, the order signal generated by the order setting unit 23, and the continuation signal generated by the duration setting unit 24. An arithmetic processing unit that outputs to the display device 100.

  When the video signal and the flashing signal generated by the data communication device 1 described above are input to the image display device 100, the image display device 100 displays a video based on the video signal and displays a flashing pattern based on the flashing signal. The corresponding light emitting element 111 of the image display device 100 is blinked. By reading the video of the image display device 100 displayed in this way with a camera or a light receiver and decoding the blinking pattern of each area included in the video, the metadata of each area can be extracted from the video. . The decoding of the blinking pattern can be performed according to an algorithm reverse to that in which the metadata is converted into the blinking pattern by the pattern setting unit 22.

  Next, the blinking signal generation operation by the blinking signal generation unit 20 will be described in detail with reference to FIG. FIG. 3 is a flowchart showing the flashing signal generation operation. In the following, a case where image data is composed of still images will be described as an example.

[Blinking pattern generation operation]
First, when metadata and coordinate data are input, the pattern setting unit 22 generates a blinking pattern for each region (step S301). Here, as shown in FIG. 4, a plurality of metadata and coordinate data are input for each combination of metadata and coordinate data corresponding to the metadata.

  An example of the configuration of the coordinate data is shown in FIG. When FIG. 5 is viewed from the front, the left to right direction on the display screen 110 of the image display device 100 is the X axis, and the top to bottom direction is the Y axis. At this time, the coordinate data of the rectangular area A is represented by the coordinates of the upper left and lower right points, that is, {(x1, y1), (x2, y2)}.

  The pattern setting unit 22 displays the metadata associated with the coordinate data in an area on the display screen 110 of the image display device 100 specified by the coordinate data in order to display the blinking time indicating the metadata. A blinking pattern that specifies the order, that is, the timing of turning on and off is generated. This blinking pattern is generated for all input metadata. At this time, the speed at which the light emitting element 111 blinks is also set. This speed can be set to about several MHz, for example. In addition, you may make it thin out the light emitting element 111 made to blink, without making all the light emitting elements contained in the area | region specified by coordinate data blink. The setting of the light emitting element 111 to be blinked is performed by the pattern setting unit 22.

[Sequence signal generation operation]
Further, the order setting unit 23 generates an order signal based on the ordering algorithm (step S302). The order signal can be generated based on various algorithms, and two typical ordering algorithms among them will be described below. Note that the order signal may be generated based on other algorithms as well as the ordering algorithm described below.

(First ordering algorithm)
The first ordering algorithm simply performs ordering based on the magnitude relation of the coordinates of each region. When embedding metadata in a plurality of areas on the display screen 110 of the screen display device 100, when reading blinking of visible light with a camera or a light receiver, the light emitting element 111 showing the metadata of the area to be read blinks. In some cases, the light emitting element 111 blinking interference indicating different metadata in the neighborhood causes noise when reading the metadata in each region, and as a result, it is difficult to read the metadata accurately. For this reason, in the first ordering algorithm, each region is simply ordered, and the metadata is not displayed in a plurality of regions at the same time, thereby preventing noise at the time of reading the metadata.

  For example, as shown in FIG. 5, when the area on the display screen 110 of the image display device 100 specified by the coordinate data has a rectangular shape, the order setting unit 23 sets the upper left coordinates as the representative points of the areas. The ordering is performed in order from the smallest coordinate value of the representative point. In the present embodiment, ordering is performed in ascending order of coordinate values in the Y direction. Note that when the values of the coordinates in the Y direction are the same, the ordering is performed in ascending order of the values of the coordinates in the X direction.

  As an example, when the coordinates of the representative points of the two regions r1, r2 are (x1, y1), (x2, y2), when y1 <y2, (x1, y1) <(x2, y2). Ordering is performed in the order of r1 and r2. When y1 = y2 and x1 <x2, (x1, y1) <(x2, y2), and the ordering is performed in the order of r1 and r2.

  Therefore, if the set of the nth region in the order is Rn (n = 1, 2,...) And the region having the kth smallest representative point is r′k (k = 1, 2,...), Rn = {R′k}.

(Second ordering algorithm)
The second ordering algorithm groups each region according to its position and performs ordering for each group. Even when metadata is embedded in multiple areas on the screen display device, areas that are not close to each other are less susceptible to blinking interference that represents the metadata of other areas. The metadata can be read at the same time. In this way, more metadata can be output per unit time by blinking metadata simultaneously in a plurality of areas. Such a second ordering algorithm will be described with reference to FIG.

  First, the order setting unit 23 sets a set of all regions set on the display screen 110 of the image display device 100 as RA and a set of arbitrary regions as R (step S601). Here, an arbitrary value is set in the set R.

  When RA and R are set, in order to set the i-th set R, first, i = 1 is set (step S602). Also, R is set as an empty set (step S603).

  When i and R are set, the order setting unit 23 adds an area having the smallest coordinate value of the representative point from among RA as an element of R (step S604). Thereby, a region serving as a reference for the region to be included in the i-th set R is set. For example, if the region having the smallest coordinate value included in RA is r′11, this r′11 is added as an element of R, that is, R = {r′11}.

  When an area is added from R to R, the order setting unit 23 adds an area having the smallest representative point coordinate from Q (R) to R (step S605). Here, Q (R) means a set of regions that are not close to the region included in R. Therefore, a region not adjacent to each other is added to R. For example, in the case of R = {r′11} described above, assuming that the region having the smallest coordinate value included in Q (R) is r′12, the order setting unit 23 adds the r′12 to R. That is, R = {r′11, r′12}.

  When a region is added to R from Q (R), the order setting unit 23 recalculates Q (R) (step S606), and checks whether Q (R) is an empty set (step S606). Step S607). If Q (R) is not an empty set (step S607: NO), the process returns to step S606. That Q (R) is not an empty set means that there is still a region in Q (R) that is not close to the region included in R. Therefore, the order setting unit 23 repeats steps S605 to 607 until there are no more regions in Q (R) that are not close to the region included in R.

  On the other hand, when Q (R) is an empty set (step S607: YES), the order setting unit 23 orders R, that is, sets R as Ri, which is the i-th set (step S608). For example, in the case of R = {r′11, r′12} described above, R1 that has been ordered is set as the first.

  When the arbitrary set R is ordered, the order setting unit 23 sets a new RA (step S609). Specifically, RA-Ri obtained by subtracting the ordered Ri from RA is set as a new RA.

  When a new RA is set, the order setting unit 23 checks whether or not the RA is an empty set (step S610). When RA is not an empty set (step S610: NO), the order setting unit 23 changes the order of the next set, that is, sets i = i + 1 (step S611), and returns to the process of step S603. That RA is not an empty set means that there is an area that is not included in any set R yet. Therefore, the order setting unit 23 repeats steps S603 to S611 described above until there is no region that is not included in any R, that is, until there is no RA element.

  On the other hand, when RA is an empty set (step S610: YES), the order setting unit 23 ends the calculation of the ordering algorithm. As a result, a sequence R1, R2, R3... Of a set of regions that are ordered and are not adjacent to each other is generated.

  In such a second ordering algorithm, various determination methods can be used to determine whether or not each region is adjacent when calculating Q (R). One method is shown below. Note that the method for determining whether or not regions are adjacent to each other is not limited to the method described below, and may be determined by another determination method.

(1) A region sharing a side or region with the reference region r is determined to be adjacent to the region r. (2) When the distance from the center of gravity of the reference region r to the center of gravity of the arbitrary region r ′ is smaller than a predetermined value c, it is determined that the region r ′ is adjacent to the region r. (3) When the minimum distance between the point on the side of the reference region r and the point on the side of the arbitrary region r is smaller than the predetermined value c, the region r ′ is adjacent to the region r Is determined. In the present embodiment, “adjacent” means that one region is closer to another region than a predetermined value. Therefore, when it is in contact with another region or overlaps with another region, it is determined as “adjacent”.

  The first and second ordering algorithms described above can perform ordering even when the regions overlap. For example, as shown in FIG. 7, even when there are four areas A to D on the display screen 110, the ordering can be performed based on the coordinates of the representative points. In FIG. 7, the coordinates of the representative points of the area A and the area D are the same. In such a case, the order of regions having the same representative point may be determined randomly. Further, for example, the coordinates of the representative point such as the lower left coordinate may be changed, and the determination may be made based on this coordinate. By doing in this way, it becomes possible to order also to the area | region where the coordinate of a representative point is the same.

[Continuous signal generation operation]
In addition, the duration setting unit 24 sets a continuation signal related to a duration for which the blinking pattern display is continued (hereinafter referred to as a display duration) (step S303). For example, the continuation signal may be set so that the blinking patterns of all the regions blink for the same time. In this case, if the time for blinking the blink pattern is t, the blink pattern display duration Dk in the set of the kth region is expressed by the following equation (1).

Dk = t (1)

  Further, the continuation signal may be set so that the blinking time becomes longer in the area having the blinking pattern with a large data amount. For example, if the data amount of the blinking pattern having the maximum data amount among the blinking patterns transmitted from the area included in the k-th set Rk is Bk, a time proportional to this Bk is allocated to the display duration Dk. That is, it is represented by the following formula (2). In the following formula (2), t ′ means an arbitrary unit time, and can be set freely as appropriate.

Dk = Bk × t ′ (2)

[Flashing signal generation operation]
When the blinking pattern, sequence signal, and continuation signal for each area are generated, the output unit 25 generates a blinking signal based on them (step S304). This blinking signal specifies the display start time and display end time of the blinking pattern in each area. An operation for generating such a blinking signal will be described below.

  As an example, a case where n regions r1, r2,..., Rn exist on the display screen 110 will be described. First, the output unit 25 classifies these regions so as to belong to any of the m sets R1, R2,..., Rm based on the order signal. At this time, when the order signal is generated by the first ordering algorithm, the quantity of the region is equal to the quantity of the set, that is, the region rn is classified into one of the n sets Rn.

  Further, the output unit 25 detects the display continuation time Dk (D1, D2, D3,..., Dm) of the set Rk of the kth region in the order based on the continuation signal.

  When the order of the set of areas and the display duration time are detected, the output unit 25 generates a blinking signal for blinking the blinking pattern of each area as follows. First, all the areas belonging to the set R1 are blinked with respective blinking patterns during the display duration D1. Next, all the regions belonging to the set R2 are blinked with respective blinking patterns during the display duration D2. In this way, the blinking pattern is sequentially blinked in the area of each set r, and when the blinking of the blinking pattern in the area belonging to the set Rm is completed, the blinking pattern in the area belonging to the set R1 is blinked again.

  At this time, the display start time and display end time of the blink pattern of each set are determined as follows. For example, the display start time of the blinking pattern by the image display device 100 is t0, the display duration of the area belonging to the first set R1 is D1, the display duration of the area belonging to the area R2 belonging to the second set R2 is D2, ..., the display duration time of the region Rm belonging to the m-th set Rm is Dm. At this time, the display start time of the region belonging to the first set R1 is t0, and the display end time is t0 + D1. In addition, the display start time of the region belonging to the second set R2 is t0 + D1, and the display end time is t0 + D1 + D2. Further, the display start time of the area belonging to the mth set Rm is t0 + D1 + D2 +... + D (m−1), and the display end time is t0 + D1 + D2 +.

  As a result, a blinking signal that specifies the blinking pattern, the area where the blinking pattern blinks, the display start time and the display end time of each area or each set of areas is generated.

  As described above, according to the present embodiment, the blinking pattern based on the metadata is displayed in the area on the display screen 110 of the image display device 100 specified by the coordinate data, so that the display is performed on the display screen 110. Metadata can be embedded anywhere in the video.

  Further, according to the present embodiment, when a plurality of metadata is embedded in a video, each region is grouped into regions that are not adjacent or adjacent to each other, and a blinking pattern is displayed for each grouped set. Thus, when the blink pattern is read by the camera or the light receiver, it is possible to prevent the blinking of the light emitting element showing the metadata of the area to be read from receiving the interference of the blinking showing the different metadata nearby. As a result, the metadata can be read accurately regardless of the size of the region and the distance from the region.

  In addition, according to the present embodiment, by using a device that outputs visible light, such as the image display device 100, the characteristics such as straightness and directivity of light are advantageously utilized, and a wireless LAN or the like is used for receiving metadata. Compared with the case where a base station is installed in the vicinity of a display device using radio waves, metadata can be received without interference. Further, since metadata can be received without interference from a plurality of adjacent light emitting elements, it is possible to provide separate metadata from a plurality of areas on the display screen.

  Further, according to the present embodiment, in order to control the timing of displaying the blinking pattern and eliminate the interference of the blinking pattern in the adjacent area, for example, as shown in FIG. You can also assign metadata. As described above, in this embodiment, an area for setting metadata can be freely set as appropriate.

  For this reason, for example, when metadata is set for an object on the display screen and an area to be transmitted from the light emitting element on the screen is set, even if the shape is complicated and the area setting is complicated, the shape of the area And the size can be set so that the receiving side can easily read without worrying about the area corresponding to another object, or the area can be easily defined. It is also possible to embed metadata for the entire screen and metadata for areas and objects in the screen.

  The communication of metadata by blinking light from a plurality of areas requires a very small amount of calculation for extracting metadata, compared to the case of watermark reading. Therefore, a larger amount of data than the watermark can be transmitted in a short time. As a result, for example, audio data corresponding to a person or object existing in the area can be transmitted as metadata simultaneously with the image. In addition to bibliographic data, copyright data, and related information addresses, additional data such as caption data and audio data can be provided in a blinking manner together with images. These can also be regarded as broad metadata.

  Note that when the image data is composed of a moving image, unlike the above-described case of a still image, there is a scene change or the like, so the area for displaying metadata changes from moment to moment. For this reason, in order to appropriately blink the blinking pattern, it is necessary to change the setting of the area and the metadata embedded in this area according to the situation of the moving image. Such a case can be dealt with by adding blinking start and end times of the blinking pattern to the coordinate data. That is, in addition to data representing a rectangular area on the image display device 100, data representing a period is added, and data including two spatial coordinates and two times is used as coordinate data. Here, the two spatial coordinates represent an area on the display screen 110 of the image display apparatus 100. The two times represent the elapsed time from the display start time of the moving image, and represent the existence start time and end time of the area as relative times, respectively. For example, as shown in FIG. 8, the spatial coordinates of the rectangular area B on the display screen 110 of the image display device 100 are ((x1, y1), (x2, y2)), and the area B changes from time t1 to time t2. Coordinate data is represented by ((x1, y1), (x2, y2), (t1, t2)).

  Each area can be dealt with by setting the coordinate data as described above, but for all areas, as in the case of a still image, the adjacent areas do not display a blinking pattern at the same time. The display start time and display duration of the blinking pattern must be determined. In this case, for example, a period in which the combination of the same areas continues on the display screen 110 of the image display device 100 can be handled by using a method equivalent to that for a still image.

  For example, a period in which the area on the display screen 110 starting from the relative time 0 from the moving image start time does not change is T0 (start time 0 = t0, end time t1), and the area on the display screen 110 starting from the relative time t1 does not change. Let T1 (start time t1, end time t2),..., And Tk (start time tk, end time t (k + 1)) be the maximum period during which the region division method on the screen starting from relative time tk does not change. At this time, in each period Tk, a blinking pattern, an order signal, and a continuation signal are generated in the same manner as in the case of the above-described still image, and a blinking signal is generated based on these, so that the image data is a moving image. Even if it exists, metadata can be displayed.

  In this embodiment, the area on the display screen 110 is represented by two coordinates. However, the form representing the area is not limited to two coordinates. For example, the area can be represented by a larger number of coordinates or a vector. It can be set freely as appropriate. Similarly, regarding the existence period of the region, not only two times but also a start time and a duration can be set as appropriate.

  In the present embodiment, as shown in FIG. 1, the video signal generated by the video signal generation unit 10 and the blinking signal generated by the blinking signal generation unit 20 are separately input to the image display device 100. However, as shown in FIG. 9, a combination of the video signal and the blinking signal may be input to the image display device 100. In the case of the data communication apparatus 2 shown in FIG. 9, the video signal generated by the video signal generation unit 10 and the blinking signal generated by the blinking signal generation unit 20 are synthesized by the synthesis unit 30 and are combined into an image as a synthesized signal. Input to the display device 100. At this time, the synthesizing unit 30 may make the frame rate of the video signal higher than the conventional one and synthesize the blinking signal therewith. As a result, the image display device 100 receives a composite signal in which a blinking signal is combined with a video signal having a high frame rate. Therefore, when the image display device 100 can output a video signal having a high frame rate, A high-quality image is output.

  The present invention can be applied to a display device that displays video.

It is a block diagram which shows the structure of the data communication apparatus concerning this invention. It is a figure for demonstrating the area | region specified by coordinate data. It is a flowchart explaining the production | generation operation | movement of a blink signal. It is a figure which shows typically the data structure of metadata and coordinate data. It is a figure which shows one structural example of coordinate data. It is a flowchart which shows operation | movement of an order setting part. It is a figure explaining the area | region which overlaps. It is a figure explaining the coordinate data when image data is comprised from a moving image. It is a block diagram which shows the other structure of the data communication apparatus concerning this invention. It is a figure which shows the structure of an image display apparatus typically. It is a block diagram which shows the structure of the conventional data communication apparatus. It is a block diagram which shows the other structure of the conventional data communication apparatus. It is a figure which shows the luminance change of (a) video signal, (b) blinking signal, and (c) synthetic | combination signal.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1, 2 ... Data communication apparatus, 10 ... Video signal generation part, 20 ... Flashing signal generation part, 21 ... Reception part, 22 ... Pattern setting part, 23 ... Order setting part, 24 ... Duration setting part, 25 ... Output part , 100 ... an image processing apparatus, 110 ... a display screen, 111 ... a light emitting element.

Claims (9)

A data communication device for transmitting communication data from a specific area of a display screen,
An acquisition means for acquiring a plurality of the communication data and area information associated with the communication data;
Transmitting means for transmitting the communication data from the area on the display screen specified by the area information, respectively. The data communication apparatus according to claim 1, wherein the transmission unit transmits the communication data in order. Grouping means for grouping the communication data for each communication data that is not adjacent to the area, based on the area information;
The data communication apparatus according to claim 1, wherein the transmission unit transmits the communication data for each group at a predetermined time interval. The data communication apparatus according to claim 3, wherein the grouping means performs grouping every time the area information changes. The data communication according to any one of claims 1 to 4, further comprising duration setting means for setting a duration for continuously transmitting the communication data according to a data amount of the communication data. apparatus. The data communication apparatus according to claim 4, further comprising a duration setting unit configured to set the duration based on communication data having a maximum data amount among communication data included in the group. Image display means for displaying an image on the display screen;
The data communication apparatus according to any one of claims 1 to 6, wherein the transmission unit transmits the communication data by superimposing the communication data on the image by a blinking pattern using visible light. A data communication method for transmitting communication data from a specific area of a display screen,
An acquisition step of acquiring a plurality of the communication data and area information associated with the communication data;
A data communication method, comprising: a transmission step of transmitting the communication data from an area on the display screen specified by the area information. A data communication program for a data communication device for transmitting communication data from a specific area of a display screen,
On the computer,
An acquisition step of acquiring a plurality of the communication data and area information associated with the communication data;
A data communication program, comprising: a transmission step of transmitting each of the communication data from an area on the display screen specified by the area information.

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