JP2016146613A - Information transmission system, symbol string generation device, symbol string decoding device, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information transmission system which allows for easy decoding of a symbol string on the receiving side, and to provide a symbol string generation device, a symbol string decoding device, and program.SOLUTION: A transmitter 100 selects a substitution rule according to the continuous aspect of the same symbol value, and generates a transmission symbol string including a non-continuous symbol string where three or more same symbol values do not continue and a substitution rule symbol, based on the substitution rule. Meanwhile, a receiver 200 discriminates the substitution rule based on the substitution rule symbol included in the transmission symbol string, and by performing inverse conversion of a symbol in the non-continuous symbol string based on that substitution rule, acquires a symbol string of one block of transmission object information, i.e., the symbol string before conversion.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an information transmission system, a symbol string generation device, a symbol string decoding device, and a program that use visible light as a transmission medium.

  There is an information transmission system in which a transmitting side emits light by changing a color (wavelength) according to information to be transmitted, and a receiving side receives light and decodes the information (for example, see Patent Document 1). In such an information transmission system, for example, red (R), green (G), and blue (B), which are base colors, are changed and output in accordance with each symbol value constituting a symbol string on the transmission side. To do. On the other hand, on the receiving side, a portion where the color change included in the image obtained by imaging is abrupt is specified as a candidate for the signal source on the transmitting side, and the symbol string is decoded into information based on the changing color.

JP 2014-168137 A

  However, when the same symbol value continues in the symbol string, the light of the same color is continuously output on the transmission side. For this reason, it is difficult to acquire a signal source on the receiving side, which hinders decoding of a symbol string.

  The present invention has been made in view of the background as described above, and is an information transmission system, a symbol string generation device, a symbol string decoding device, and a program capable of easily decoding a symbol string on the receiving side. The purpose is to provide.

In order to achieve the above object, an information transmission system according to the present invention includes:
An information transmission system including a transmission device and a reception device using visible light as a transmission medium,
The transmitter is
Generating means for generating a multi-level symbol sequence using visible light as a transmission medium;
In the multi-value symbol sequence generated by the generating means, if there is a continuous symbol sequence that is a symbol sequence in which the same symbol value continues for a predetermined number or more, this continuous symbol sequence is assigned a predetermined number of symbol values. First control means for controlling the generating means to replace with a discontinuous symbol string that is not a continuous symbol string and add replacement rule information;
With
The receiving device is:
Obtaining means for obtaining a symbol string;
When the replacement rule information is included in the symbol sequence acquired by the acquisition unit, the acquisition unit performs control to replace a non-consecutive symbol sequence included in the symbol sequence with the continuous symbol sequence. Control means,
It is characterized by providing.

In order to achieve the above object, a symbol string generation device according to the present invention includes:
Generating means for generating a multi-level symbol sequence transmitted using visible light as a transmission medium;
Control means for controlling the generating means to replace the multi-valued symbol string generated by the generating means with a non-consecutive symbol string that is a symbol string in which the same symbol value does not continue for a predetermined number or more;
It is characterized by providing.

  According to the present invention, it is possible to easily decode a symbol string on the receiving side.

It is a figure which shows the structure of an information transmission system. It is a figure which shows the structure of the transmitter shown in FIG. It is a figure which shows the structure of the receiver shown in FIG. It is a flowchart which shows the operation | movement of the transmission process by a transmitter. It is a figure which shows an example of the production | generation process of a transmission symbol. It is a figure which shows an example of a replacement rule table. It is a figure which shows an example of the arrangement | sequence of the symbol used as the application object of a replacement rule. It is a figure which shows an example of the content of the replacement rule. It is a flowchart which shows the operation | movement of the reception process by a receiver. It is a figure which shows an example of a symbol sequence conversion table. It is a figure which shows an example of the format of a transmission symbol, and a light emission aspect.

  The information transmission system according to the first embodiment of the present invention will be described below. As illustrated in FIG. 1, the information transmission system 1 according to the first embodiment includes a transmission device 100 and a reception device 200.

  In the information transmission system 1, the transmission device 100 and the reception device 200 can communicate from the transmission device 100 to the reception device 200 using light as a transmission medium.

  The transmitting apparatus 100 generates a symbol string in which each digit is composed of ternary symbols of 0, 1, and 2 in the ternary system from information to be transmitted, and further, with visible light corresponding to the symbol value by modulation. It is converted into an optical signal that changes in time series of a certain red (R), green (G), and blue (B) and output. In the first embodiment, symbol value 0 is converted to red (R), symbol value 1 is converted to green (G), and symbol value 2 is converted to blue (B).

  The receiving device 200 is an information device having an imaging (light reception) function such as a smartphone, and receives an optical signal from the transmission device 100 by imaging the transmission device 100 included in the imaging range. In addition, the receiving device 200 displays an image obtained by imaging. The receiving apparatus 200 decodes the symbol sequence from the received optical signal, and further displays information indicated by the symbol sequence.

  Next, the transmission device 100 will be described. As illustrated in FIG. 2, the transmission device 100 includes a control unit 102, a memory 104, and a transmission unit 114.

  The control unit 102 includes a CPU (Central Processing Unit), and executes software processing according to a program stored in the memory 104, and functions to realize various functions included in the transmission device 100.

  The memory 104 is, for example, a RAM (Random Access Memory) serving as a work area and a ROM (Read Only Memory) storing a basic operation program. The memory 104 stores various information (programs and the like) used for control and the like in the transmission device 100.

  The encoding unit 110 in the control unit 102 corresponds to a generation unit, a first determination unit, and a first control unit. The encoding unit 110 divides information to be transmitted into one block unit, and for each block, a 6-digit symbol string (transmission) in which each digit is composed of ternary symbols of 0, 1, and 2 according to the ternary system. A symbol string for one block of target information) is generated.

  Furthermore, encoding section 110 includes a pattern (AAA pattern) in which three or more identical symbol values continue in a symbol string for one block of information to be transmitted (a symbol string for one block of information to be transmitted is continuous). In the case of a symbol string), based on a predetermined replacement rule, the AAA pattern symbol is converted into a symbol having a pattern in which three or more identical symbol values are not consecutive, and a six-digit non-consecutive symbol string is generated. . In addition, encoding section 110 includes a pattern (AABB pattern) in which two identical symbol values are consecutive in a symbol string for one block of information to be transmitted and two or more consecutive patterns are consecutive. In this case (when the 6-digit symbol string is a continuous symbol string), the AABB pattern symbol is converted to a symbol other than the AABB pattern based on a predetermined replacement rule, and a 6-digit non-consecutive symbol is converted. Generate a column. Further, encoding section 110 generates a transmission symbol sequence by adding a replacement rule symbol that is a symbol indicating a replacement rule, a non-continuation guarantee symbol for guaranteeing non-continuity of the symbol sequence, and a header. Details of generation of the transmission symbol sequence will be described later.

  Modulation section 111 performs modulation based on the transmission symbol sequence, and associates symbol value 0 with light of red (R), symbol value 1 of green (G), and symbol value 2 of blue (B). The drive unit 112 performs control to temporally change red (R), green (G), and blue (B) light associated with the symbol value.

  The transmission unit 114 is, for example, a light emitting diode (LED), and outputs red (R), green (G), and blue (B) light while temporally changing under the control of the driving unit 112. .

  Next, the receiving apparatus 200 will be described. The receiving device 200 displays a captured image and functions as a communication device for receiving information from the transmitting device 100. As illustrated in FIG. 3, the reception device 200 includes a control unit 202, a memory 204, an operation unit 206, a display unit 207, a wireless communication unit 208, an antenna 210, and an imaging unit 214.

  The control unit 202 is configured by a CPU. The control unit 202 functions to realize various functions included in the reception device 200 by executing software processing according to a program stored in the memory 204.

  The memory 204 is, for example, a RAM or a ROM. The memory 204 stores various information (programs and the like) used for control and the like in the receiving device 200.

  The operation unit 206 is a touch panel disposed on the upper surface of the display area of the display unit 207, and is an interface used for inputting user operation details. The display unit 207 includes, for example, an LCD (Liquid Crystal Display), a PDP (Plasma Display Panel), an EL (Electro-Luminescence) display, and the like, and displays an image.

  The wireless communication unit 208 is configured using, for example, a radio frequency (RF) circuit, a base band (BB) circuit, or the like. The wireless communication unit 208 transmits and receives wireless signals via the antenna 210. The wireless communication unit 208 also modulates the transmission signal and demodulates the reception signal.

  The imaging unit 214 is disposed on the surface of the housing of the receiving device 200 opposite to the surface on which the display unit 207 is installed. The imaging unit 214 includes a lens and a light receiving element. The lens is composed of a zoom lens or the like, and moves by zoom control and focus control by the control unit 202. The imaging angle of view and optical image of the imaging unit 214 are controlled by movement of the lens. The light receiving element is composed of a plurality of light receiving elements regularly arranged two-dimensionally on the light receiving surface. The light receiving element is, for example, an imaging device such as a photodiode, a CCD (Charge Coupled Device), or a CMOS (Complementary Metal Oxide Semiconductor). The imaging unit 214 performs imaging, captures (receives) an incident optical image with an imaging field angle within a predetermined range based on a control signal from the control unit 202, and sequentially outputs image signals within the imaging field angle. And output to the control unit 202.

  Each time the image signal from the imaging unit 214 is input, the image generation unit 232 in the control unit 202 converts the image signal into digital data to generate a frame.

  The decoding unit 234 in the control unit 202 corresponds to an acquisition unit, a second determination unit, and a second control unit. The decoding unit 234 searches for a location (change region) where a hue change occurs in frames input continuously in time series. Specifically, the decoding unit 234 determines the brightness of each pixel in the image data of the frame. Furthermore, the decoding unit 234 is a candidate (candidate region) for a portion (change region) in which a hue change is caused by receiving light from the transmission unit 114 in the transmission device 100 for a pixel whose brightness is a predetermined value or more. Is considered. Furthermore, the decoding unit 234 determines the hue at the same coordinates in the candidate area in each of the predetermined number of frames acquired most recently. As a result of the determination, if the frame has a hue value at the coordinates in the candidate area, it is the first predetermined value and the other frame has the second predetermined value. The decoding unit 234 regards the candidate area as a change area. The change area is an area that is a candidate for a transmission unit 114 in the transmission apparatus 100, that is, a signal source.

  If there is a change area, the decoding unit 234 then obtains the hue value of the change area in the frame for each imaging, and changes the color of the change area corresponding to the hue value to red (R), green ( G) or blue (B). Further, the decoding unit 234 generates symbols corresponding to the determined red (R), green (G), and blue (B), and further generates a transmission symbol sequence that is a set of these symbols.

  Next, the decoding unit 234 determines a replacement rule based on the replacement rule symbol included in the transmission symbol sequence. Further, the decoding unit 234 determines whether or not the symbol is replaced based on the determined replacement rule, and if so, reversely converts the symbol based on the determined replacement rule, and transmits the symbol. A 6-digit symbol string (symbol string for one block of information to be transmitted) before being converted in apparatus 100 is acquired. Details of acquisition of a 6-digit symbol string will be described later.

  Further, the decoding unit 234 acquires transmission target information for one block from a symbol string for one block of transmission target information. The image generation unit 232 generates an image of information to be transmitted acquired by the decoding unit 234. A display control unit 236 in the control unit 202 performs control to display an image of information to be transmitted on the display unit 207.

  Next, the operation of the information transmission system 1 in the first embodiment will be described. In the information transmission system 1, transmission processing by the transmission device 100 and reception processing by the reception device 200 are performed.

  FIG. 4 is a flowchart illustrating the operation of the transmission process performed by the transmission apparatus 100. The encoding unit 110 in the control unit 102 divides information to be transmitted into one block unit, and each block has 6 digits each consisting of a ternary symbol of 0, 1, 2 in ternary system. Symbol sequence (symbol sequence for one block of information to be transmitted) is generated (step S101). By the process of step S101, for example, as shown in FIG. 5A, a symbol string for one block of information to be transmitted, which is a 6-digit symbol string of digits 0 to 5, is generated.

  Next, the encoding unit 110 includes a pattern (AAA pattern) in which three or more identical symbol values are continuous in a symbol string for one block of information to be transmitted, or two identical symbol values, and the 2 It is determined whether or not two or more consecutive patterns (AABB pattern) are included (step S102). Specifically, the encoding unit 110 adds “000”, “111”, “222” as AAA patterns to symbol strings for one block of information to be transmitted, and “0011”, “0022”, “ABB” as AAA patterns. It is determined whether or not the patterns “1100”, “1122”, “2200”, and “2211” are included. For example, when the symbol string for one block of information to be transmitted is “0000011”, “001111”, “111111”, etc., a pattern in which three or more identical symbol values continue (AAA pattern) and the same symbol value Both two consecutive patterns and two or more consecutive patterns (AABB pattern) are included. In this case, in the first embodiment, priority is given to a pattern (AAA pattern) in which three or more identical symbol values are continued, and it is determined that a pattern (AAA pattern) in which three or more identical symbol values are continued is included.

  A pattern (AAA pattern) in which three or more identical symbol values are continuous in a symbol sequence for one block of information to be transmitted, or two identical symbol values are continuous and two or more consecutive patterns are consecutive. When the pattern to be performed (AABB pattern) is included (step S102; YES), the encoding unit 110 selects a replacement rule according to the continuous form of the same symbol value (step S103).

  FIG. 6 is a diagram illustrating an example of a replacement rule table including a plurality of replacement rules. FIG. 7 is a diagram illustrating an example of a sequence of symbols to which the replacement rule is applied. Also, the information on the replacement table shown in FIG. 6 and the information on the arrangement of symbols to which the replacement rule is applied in FIG. 7 are stored in the memory in the transmission device 100 and the memory 204 in the reception device 200.

  As shown in FIG. 6, there are nine types of replacement rules with indices 0 to 8, each of which is a two-digit replacement rule in which each digit is composed of ternary symbols 0, 1, and 2 in ternary system. Symbols (replacement rule information) are associated. The replacement table is stored in the memory in the transmission device 100 and the memory 204 in the reception device 200.

  As shown in FIGS. 6 and 7, the replacement rule for index 0 is that when the same symbol value is included in digits 0 to 2 of the symbol string for one block of information to be transmitted, This is a replacement rule applied when replacing a symbol value, and the corresponding replacement rule symbol is “00”.

  The replacement rule of index 1 is a replacement rule applied when replacing the symbol values of the digits 1 to 3 when the same symbol value is included in the digits 1 to 3 of the symbol string for one block of information to be transmitted. And the corresponding replacement rule symbol is “01”.

  The replacement rule of index 2 is a replacement rule applied when replacing the symbol values of the digits 2 to 4 when the same symbol values are included in the digits 2 to 4 of the symbol string for one block of information to be transmitted. And the corresponding replacement rule symbol is “02”.

  The replacement rule of index 3 is a replacement rule applied when replacing the symbol values of the digits 3 to 5 when the same symbol values are included in the digits 3 to 5 of the symbol string for one block of information to be transmitted. And the corresponding replacement rule symbol is “10”.

  When the same symbol value is included in both digits 0 to 2 and digits 3 to 5 of the symbol string for one block of information to be transmitted, the replacement rule of index 4 is that digits 0 to 2 and digits 3 to 5 This is a replacement rule applied when replacing a symbol value, and the corresponding replacement rule symbol is “11”.

  The replacement rule of index 5 is applied when replacing the symbol values of the digits 0 to 3 when the symbol values of the AABB pattern are included in the digits 0 to 3 of the symbol string for one block of information to be transmitted. This is a replacement rule, and the corresponding replacement rule symbol is “12”.

  The replacement rule of index 6 is applied when replacing the symbol values of the digits 1 to 4 when the symbol values of the AABB pattern are included in the digits 1 to 4 of the symbol string for one block of information to be transmitted. This is a replacement rule, and the corresponding replacement rule symbol is “20”.

  The replacement rule of index 7 is applied when replacing the symbol values of the digits 2 to 5 when the symbol values of the AABB pattern are included in the digits 2 to 5 of the symbol string for one block of transmission target information. This is a replacement rule, and the corresponding replacement rule symbol is “21”.

  The replacement rule of index 8 is a replacement rule that no replacement is performed, and the corresponding replacement rule symbol is “22”.

  In step S103, the encoding unit 110 includes a pattern (AAA pattern) in which three or more identical symbol values are included in a symbol string for one block of information to be transmitted, or two identical symbol values in succession, In addition, it is determined which pattern of two or more consecutive patterns (AABB pattern) corresponds to one of the symbol arrangements shown in FIG. 7, and the corresponding replacement rule index of the symbol is selected. To do.

  Again, referring back to FIG. On the other hand, a pattern (AAA pattern) in which three or more identical symbol values are continuous in a symbol string for one block of information to be transmitted, two consecutive identical symbol values, and two consecutive patterns. When none of the above-described continuous patterns (AABB patterns) is included (step S102; NO), the encoding unit 110 selects the “no replacement” replacement rule (the index 8 replacement rule).

  Again, referring back to FIG. After step S103 or step S104, the encoding unit 110 converts the symbol based on the selected replacement rule (step S105).

  FIG. 8 is a diagram illustrating an example of the contents of the replacement rule. Information on the contents of the replacement rule shown in FIG. 8 is stored in the memory 104 in the transmission device 100 and the memory 204 in the reception device 200. As shown in FIG. 8, the replacement rules of indexes 0 to 4 convert a pattern in which three or more identical symbol values are continuous (AAA pattern) into a pattern in which three or more identical symbol values are not consecutive (ABC pattern). It is. For example, “000” is converted into “012”, “111” is converted into “120”, and “222” is converted into “201”. The replacement rules of indexes 5 to 7 are such that a pattern (AABB pattern) in which two identical symbol values are continuous and two or more consecutive patterns are continuous (AABB pattern) is changed to another pattern (ABCB or ACBC). To convert. For example, “0011” is “0121”, “0022” is “0212”, “1100” is “1202”, “1122” is “1020”, “2200” is “2010”, and “2211” is “2101”. Each is converted.

  When step S105 is executed after step S103, the encoding unit 110 performs transmission based on the content of the replacement rule shown in FIG. 8 corresponding to the indexes 0 to 7 of the replacement rule selected in step S103. A pattern of three or more consecutive identical symbol values (AAA pattern), or two consecutive identical symbol values and two or more consecutive patterns included in a symbol string for one block of information A continuous pattern (AABB pattern) is converted. As a result of the processing in step S105, for example, as shown in FIG. 5B, a symbol sequence (non-consecutive symbol sequence) in which three or more identical symbol values are not consecutive is generated for one block of information to be transmitted. Is done.

  On the other hand, when step S105 is executed after step S104, the encoding unit 110 does not perform symbol conversion because the index of the replacement rule selected in step S104 is 8.

  Next, the encoding unit 110 generates a transmission symbol sequence by adding a replacement rule symbol, a non-consecutive guarantee symbol, a parity, and a header to the non-consecutive symbol sequence (step S106).

  Specifically, encoding section 110 adds a replacement rule symbol corresponding to the replacement rule selected in step S103 or step S104 to the discontinuous symbol string. Thereby, a symbol string as shown in FIG. 5B is generated. Next, encoding section 110 adds a non-continuous guarantee symbol between the non-continuous symbol sequence and the replacement rule symbol. Here, a symbol value different from the symbol value of the last digit of the non-consecutive symbol string and the symbol value of the first digit of the replacement rule symbol is added to the non-continuous guarantee symbol as a non-continuous guarantee symbol. As a result, a symbol string as shown in FIG. 5C is generated. Next, the encoding unit 110 adds a parity symbol after the replacement rule symbol. The parity symbol is, for example, the value of the first digit obtained by adding the symbol values of the non-consecutive symbol string, the replacement rule symbol, and the non-continuous guarantee symbol. Thereby, a symbol string as shown in FIG. 5D is generated. Furthermore, the encoding unit 110 adds a header (BK) for two symbols before the non-consecutive symbol string. As a result, finally, a transmission symbol sequence in which a header (BK) for two symbols is added to a 10-digit symbol sequence as shown in FIG. 5E is generated.

  Next, modulation section 111 performs modulation based on the transmission symbol sequence, and associates symbol value 0 with light of red (R), symbol value 1 of green (G), and symbol value 2 of blue (B). The drive unit 112 performs control to temporally change red (R), green (G), and blue (B) light associated with the symbol value. The transmission unit 114 outputs red (R), green (G), and blue (B) light while temporally changing under the control of the driving unit 112 (step S107). For example, as shown in FIG. 6F, light of red (R) corresponding to symbol value 0, green (G) corresponding to symbol value 1, and blue (B) corresponding to symbol value 2 are output. At the same time, the lights corresponding to the header are turned off.

  FIG. 9 is a flowchart illustrating an operation of reception processing by the reception device 200 according to the first embodiment. Note that it is assumed that the receiving apparatus 200 recognizes the configuration of the transmission symbol sequence generated by the transmitting apparatus 100 and the replacement rule in advance by executing an application program for acquiring information to be transmitted. When the user of the receiving apparatus 200 recognizes that the light hue of the transmitting unit 114 in the transmitting apparatus 100 has changed, an operation for performing imaging by starting an application program for acquiring information to be transmitted I do. The imaging unit 214 in the reception device 200 receives an optical signal by imaging an imaging range including the transmission unit 114 of the transmission device 100 in accordance with a user operation (step S201).

  Next, the decoding unit 234 in the control unit 202 generates a transmission symbol sequence based on the received optical signal (step S202). Specifically, every time an image signal from the imaging unit 214 is input, the image generation unit 232 converts the image signal into digital data and generates a frame. Further, the decoding unit 234 in the control unit 202 searches for a change area in the frame, and based on the hue value in the change area, the red (R) light has a symbol value of 0 and the green (G) light has a symbol value of 1. The transmission symbol string is generated by associating with the light symbol value 2 of blue (B) and associating the header “BK” with the extinction. Furthermore, the decoding unit 234 performs a parity check based on the parity symbol included in the transmission symbol sequence, and determines the presence or absence of a signal error. If there is no signal error, the operation after step S203 described later is performed.

  Next, the decoding unit 234 extracts a replacement rule symbol included in the transmission symbol sequence, and determines a replacement rule corresponding to the replacement rule symbol (step S203). Furthermore, the decoding unit 234 determines whether or not symbol substitution has been performed in the transmission apparatus 100 (step S204). Specifically, the decoding unit 234 determines that symbol replacement has been performed if the replacement rule index is any of 0 to 7, and if the replacement rule index is 8, It is determined that no replacement has been performed.

  When symbol replacement is performed in the transmission apparatus 100 (step S204; YES), the decoding unit 234 performs inverse conversion of the symbol based on the replacement rule determined in step S203 (step S205). Specifically, the decoding unit 234 specifies the position of the symbol that has undergone the replacement as shown in FIG. 7 based on the replacement rule determined in step S203. Furthermore, the decoding unit 234 performs conversion opposite to the content of the replacement rule as shown in FIG. 8 for the replaced symbol. For example, according to the replacement rule of the index 0 to 1, “000” is used when the replaced symbol is “012”, and “111” when the replaced symbol is “120”. When the replaced symbol is “201”, it is inversely converted to “222”. Further, according to the replacement rules of the indexes 5 to 7, when the replaced symbol is “0121”, “0011”, and when the replaced symbol is “0212”, “0022” "1100" when the symbol that has been replaced is "1202", "1122" when the replaced symbol is "1020", and "2010" when the replaced symbol is Is converted back to “2200”, and when the replaced symbol is “2101”, it is inversely converted to “2211”.

  After a negative determination in step S204 (step S204; NO) or after step S205, the decoding unit 234 acquires a symbol sequence for one block of information to be transmitted from the transmission symbol sequence after inverse transformation (step S206). . Next, the decoding unit 234 acquires transmission target information for one block from a symbol string for one block of transmission target information (step S207).

  As described above, in the information transmission system 1 according to the first embodiment, the encoding unit 110 in the transmission apparatus 100 has a pattern in which three or more identical symbol values are consecutive in a symbol string for one block of information to be transmitted. (AAA pattern) or when two identical symbol values are continuous and a pattern in which two or more consecutive patterns are continuous (AAABB pattern) is included, encoding section 110 has the same symbol value. A replacement rule is selected in accordance with the continuous mode, and the AAA pattern or AABB pattern is converted based on the replacement rule to generate a symbol sequence (non-consecutive symbol sequence) in which three or more identical symbol values are not continuous. Furthermore, the encoding unit 110 generates a transmission symbol sequence by adding a replacement rule symbol for specifying a replacement symbol, a non-continuation guarantee symbol for guaranteeing non-continuity of symbol values, etc. to the non-continuous symbol sequence. To do.

  On the other hand, decoding section 234 in receiving apparatus 200 determines a replacement rule based on the replacement rule symbol included in the transmission symbol sequence, and inversely converts the symbols in the discontinuous symbol sequence based on the replacement rule. Then, a symbol sequence for one block of information to be transmitted, which is a symbol sequence before being converted in the transmission apparatus 100, is acquired.

  As described above, the transmitter 100 converts the symbol based on the replacement rule, thereby preventing three or more lights of the same color from being output in succession, resulting in a drastic color change. This makes it easier to identify candidate change areas. Further, since the transmission device 100 notifies the reception device 200 of the replacement rule, the reception device 200 can reverse-convert symbols based on the replacement rule, and obtain a symbol string for one block of information.

  In the first embodiment, the number of replacement rules is as small as eight types, and it is not necessary to store a huge amount of information at the time of replacement, reducing the necessary storage capacity in the memories 104 and 204, the control unit 102, The processing load in 202 can be reduced.

  Next, an information transmission system according to the second embodiment of the present invention will be described. As in the first embodiment, the information transmission system 1 according to the second embodiment includes a transmission device 100 and a reception device 200 as shown in FIG. Further, since the transmission device 100 is the same as the configuration shown in FIG. 2 and the reception device 200 is the same as the configuration shown in FIG. 3, portions different from the first embodiment will be described below.

  The encoding unit 110 in the control unit 102 of the transmission device 100 uses an 8B6T encoding method to add 8-bit information “00” to 6-bit information that is one block of information to be transmitted. From this information, a 6-digit symbol string is generated in which each digit is composed of ternary symbols of 0, 1, 2 in ternary system. At this time, the encoding unit 110 generates a 6-digit symbol string such that two consecutive symbols with the same value are allowed but not more than three, that is, three or more equivalent symbols are not consecutive. .

  FIG. 10 is a diagram illustrating an example of a symbol string conversion table used for 8B6T encoding. The information of the symbol string conversion table shown in FIG. 10 is stored in the memory 104, for example, and is obtained by converting 8-bit information (left column) expressed in hexadecimal and the 8-bit information in the right column. The correspondence with a digit symbol string (right column) is shown. The encoding unit 110 uses the symbol string conversion table shown in FIG. 10 to calculate each digit from 8-bit information obtained by adding 2-bit information “00” to 6-bit information corresponding to one block of information to be transmitted. Generates a 6-digit symbol string composed of ternary symbols of 0, 1, and 2 in the ternary system, thereby converting 64-bit information of 00 to 3F into different 6-digit symbol strings. A 6-digit symbol string can be generated so that three or more symbols having the same value do not continue.

  Further, the encoding unit 110 generates a transmission symbol sequence including a plurality of 6-digit symbol sequences. FIG. 11A shows an example of a transmission symbol string. Encoding section 110 includes a plurality of 6-digit symbol strings, and adds non-continuous guarantee symbols for guaranteeing non-continuity of three or more equivalent symbols between two consecutive six-digit symbol strings. Generated payload. Further, the encoding unit 110 adds a header, a data type and data length symbol sequence, and a non-continuous guarantee symbol to the beginning of the payload, and adds a non-continuous guarantee symbol and a frame check sequence (FCS) to the last part of the payload. Is added to generate a transmission symbol sequence. If two consecutive 6-digit symbol sequences are simply connected, it is possible that up to four consecutive symbols with the same value may occur. However, by adding a non-consecutive guarantee symbol, three symbols with the same value are added. It is guaranteed that it will not continue.

  Modulation section 111 performs modulation based on the transmission symbol sequence, and associates symbol value 0 with light of red (R), symbol value 1 of green (G), and symbol value 2 of blue (B). The drive unit 112 performs control to temporally change red (R), green (G), and blue (B) light associated with the symbol value. The transmission unit 114 is, for example, a light emitting diode (LED), and outputs red (R), green (G), and blue (B) light while temporally changing under the control of the driving unit 112. . For example, the transmission symbol sequence in FIG. 11A is emitted in the form of FIG.

  On the other hand, the decoding unit 234 in the control unit 202 of the receiving apparatus 200 searches for a location (change region) where a hue change occurs in frames that are continuously input in time series. If there is a change area, the decoding unit 234 then obtains the hue value of the change area in the frame for each imaging, and changes the color of the change area corresponding to the hue value to red (R), green ( G) or blue (B). Further, the decoding unit 234 generates symbols corresponding to the determined red (R), green (G), and blue (B), and further generates a transmission symbol sequence that is a set of these symbols. The memory 204 stores information on the symbol string conversion table and information on the format of the transmission symbol string. The decoding unit 234 extracts a 6-digit symbol sequence in the transmission symbol sequence based on the transmission symbol sequence format information. Further, the decoding unit 234 performs inverse conversion on the 6-digit symbol string based on the information in the symbol string conversion table, and acquires 6-bit information corresponding to one block of information to be transmitted.

  As described above, in the information transmission system 1 according to the second embodiment, the encoding unit 110 in the transmission device 100 adds the 2-bit information “00” to the 6-bit information that is one block of information to be transmitted. From the 8-bit information to which is added, each digit is composed of ternary symbols of 0, 1, and 2 in the ternary system, and a 6-digit symbol string in which three or more equivalent symbols are not consecutive is generated. Further, the encoding unit 110 generates a transmission symbol sequence including a plurality of 6-digit symbol sequences. At this time, a non-continuous guarantee symbol is added between two consecutive 6-digit symbol strings. As a result, a transmission symbol string including a plurality of six-digit symbol strings can be transmitted, and by adding a non-continuous guarantee symbol, it is ensured that three or more symbols having the same value do not continue.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation and application are possible. For example, in the first embodiment described above, the replacement rules shown in FIGS. 6 to 8 are used. However, the present invention is not limited to this, and it is possible to perform inverse symbol conversion in the receiving device in accordance with symbol conversion in the transmitting device 100. Any replacement rule that guarantees the uniqueness and reversibility of the conversion process is acceptable.

  In the second embodiment described above, two consecutive symbols having the same value are allowed, but may not be allowed. In this case, a symbol string conversion table that satisfies the condition that two symbols having the same value are not consecutive is prepared.

  The receiving device 200 may be any communication device as long as it can capture and communicate. For example, a PHS (Personal Handy-phone System), a PDA (Personal Digital Assistant or Personal Data Assistance), a tablet PC (Personal Computer), a game device, a portable music player, and the like may be used.

  Alternatively, a device having both the function of the receiving device 200 and the function of the transmitting device 100 may be prepared so that both functions can be used properly according to the situation.

  In each of the above embodiments, the program to be executed is a computer-readable recording such as a flexible disk, a CD-ROM (Compact Disc Read-Only Memory), a DVD (Digital Versatile Disc), and an MO (Magneto-Optical disc). A system that executes the above-described processing may be configured by storing and distributing the program on a medium and installing the program.

  Alternatively, the program may be stored in a disk device or the like of a predetermined server on a network NW such as the Internet, and may be downloaded, for example, superimposed on a carrier wave.

  Note that when the above functions are realized by sharing an OS (Operating System) or when the functions are realized by cooperation between the OS and an application, only the part other than the OS may be stored in a medium and distributed. You may also download it.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to the specific embodiment which concerns, This invention includes the invention described in the claim, and its equivalent range It is. Hereinafter, the invention described in the scope of claims of the present application will be appended.

(Appendix 1)
An information transmission system including a transmission device and a reception device using visible light as a transmission medium,
The transmitter is
Generating means for generating a multi-level symbol sequence using visible light as a transmission medium;
In the multi-value symbol sequence generated by the generating means, if there is a continuous symbol sequence that is a symbol sequence in which the same symbol value continues for a predetermined number or more, this continuous symbol sequence is assigned a predetermined number of symbol values. First control means for controlling the generating means to replace with a discontinuous symbol string that is not a continuous symbol string and add replacement rule information;
With
The receiving device is:
Obtaining means for obtaining a symbol string;
When the replacement rule information is included in the symbol sequence acquired by the acquisition unit, the acquisition unit performs control to replace a non-consecutive symbol sequence included in the symbol sequence with the continuous symbol sequence. Control means,
An information transmission system comprising:

(Appendix 2)
Generating means for generating a multi-level symbol sequence transmitted using visible light as a transmission medium;
In the multi-value symbol sequence generated by the generating means, if there is a continuous symbol sequence that is a symbol sequence in which the same symbol value continues for a predetermined number or more, this continuous symbol sequence is assigned a predetermined number of symbol values. Control means for controlling the generating means to replace with a discontinuous symbol string that is not a continuous symbol string and add replacement rule information;
A symbol string generation device comprising:

(Appendix 3)
The continuous symbol sequence has a plurality of types of patterns,
The symbol sequence generation according to appendix 2, wherein the control unit causes the generation unit to replace the continuous symbol sequence with the non-consecutive symbol sequence according to a replacement rule corresponding to the plurality of types of patterns. apparatus.

(Appendix 4)
The symbol string generation device according to attachment 3, further comprising storage means for storing the plurality of types of patterns and the replacement rules in association with each other.

(Appendix 5)
The symbol string generation device according to appendix 3 or 4, wherein the replacement rule information is a symbol string of a predetermined length indicating the replacement rule.

(Appendix 6)
The symbols constituting the symbol row are any of a plurality of colors whose hues are separated by the same distance from each other,
The symbol string generation device according to any one of appendices 2 to 5, further comprising output means for outputting a symbol string generated by the control means to the device that emits light of a plurality of types of colors.

(Appendix 7)
An acquisition means for acquiring a symbol string transmitted using visible light as a transmission medium;
Control means for performing control to replace the non-consecutive symbol sequence included in the symbol sequence with a continuous symbol sequence when the replacement rule information is present in the symbol sequence acquired by the acquisition unit;
A symbol string decoding apparatus comprising:

(Appendix 8)
The continuous symbol sequence has a plurality of types of patterns,
The control unit according to claim 7, wherein the control unit performs control to replace the non-consecutive symbol sequence with the continuous symbol sequence with respect to the obtaining unit according to a replacement rule corresponding to the plurality of types of patterns. Symbol sequence decoder.

(Appendix 9)
9. The symbol string decoding apparatus according to appendix 8, further comprising storage means for storing the plurality of types of patterns and the replacement rule in association with each other.

(Appendix 10)
10. The symbol string decoding apparatus according to appendix 8 or 9, wherein the replacement rule information is a symbol string of a predetermined length indicating the replacement rule.

(Appendix 11)
The symbols constituting the symbol row are any of a plurality of colors whose hues are separated by the same distance from each other,
The symbol string decoding device according to any one of appendices 7 to 10, further comprising an input unit that inputs the symbol string from the device that receives the light of the plurality of types of colors.

(Appendix 12)
Computer
Generating means for generating a multi-level symbol sequence transmitted using visible light as a transmission medium;
In the multi-value symbol sequence generated by the generating means, if there is a continuous symbol sequence that is a symbol sequence in which the same symbol value continues for a predetermined number or more, this continuous symbol sequence is assigned a predetermined number of symbol values. Control means for controlling the generating means to replace with a discontinuous symbol string which is not a continuous symbol string and add replacement rule information;
Program to function as.

(Appendix 13)
Computer
An acquisition means for acquiring a symbol string transmitted using visible light as a transmission medium;
Control means for controlling the acquisition means to replace a non-consecutive symbol sequence included in the symbol sequence with a continuous symbol sequence when there is substitution rule information in the symbol sequence acquired by the acquisition unit;
Program to function as.

(Appendix 14)
Generating means for generating a multi-level symbol sequence transmitted using visible light as a transmission medium;
Control means for controlling the generating means to replace the multi-valued symbol string generated by the generating means with a non-consecutive symbol string that is a symbol string in which the same symbol value does not continue for a predetermined number or more;
A symbol string generation device comprising:

(Appendix 15)
Computer
Generating means for generating a multi-level symbol sequence transmitted using visible light as a transmission medium;
Control means for controlling the generating means so as to replace the multi-valued symbol string generated by the generating means with a non-consecutive symbol string that is a symbol string in which the same symbol value does not continue for a predetermined number or more;
Program to function as.

  DESCRIPTION OF SYMBOLS 1 ... Information transmission system, 100 ... Transmission apparatus, 102 ... Control part, 104 ... Memory, 110 ... Coding part, 111 ... Modulation part, 112 ... Drive part, 114 ... Transmission part, 200 ... Reception apparatus, 202 ... Control part , 204 ... Memory, 206 ... Operation part, 207 ... Display part, 208 ... Wireless communication part, 210 ... Antenna, 214 ... Imaging part, 232 ... Image generation part, 234 ... Decoding part, 236 ... Display control part

In order to achieve the above object, an information transmission system according to the present invention includes:
An information transmission system including a transmission device and a reception device using visible light as a transmission medium,
The transmitter is
Generating means for generating a multi-level symbol sequence using visible light as a transmission medium;
First control means for controlling the generating means to replace the multi-valued symbol string generated by the generating means with a non-consecutive symbol string that is a symbol string in which the same symbol value does not continue for a predetermined number or more ;
With
The receiving device is:
Obtaining means for obtaining the discontinuous symbol sequence ;
Second control means for controlling the acquisition means to replace the non-continuous symbol string acquired by the acquisition means with the multi-value symbol string according to a predetermined rule ;
It is characterized by providing.

In order to achieve the above object, a symbol string generation device according to the present invention includes:
Generating means for generating a multi-level symbol sequence transmitted using visible light as a transmission medium;
Control means for controlling the generating means so as to replace the multi-value symbol string generated by the generating means with a non-consecutive symbol string that is a symbol string in which the same symbol value does not continue for a predetermined number or more;
It is characterized by providing.

Claims (15)

An information transmission system including a transmission device and a reception device using visible light as a transmission medium,
The transmitter is
Generating means for generating a multi-level symbol sequence using visible light as a transmission medium;
In the multi-value symbol sequence generated by the generating means, if there is a continuous symbol sequence that is a symbol sequence in which the same symbol value continues for a predetermined number or more, this continuous symbol sequence is assigned a predetermined number of symbol values. First control means for controlling the generating means to replace with a discontinuous symbol string that is not a continuous symbol string and add replacement rule information;
With
The receiving device is:
Obtaining means for obtaining a symbol string;
When the replacement rule information is included in the symbol sequence acquired by the acquisition unit, the acquisition unit performs control to replace a non-consecutive symbol sequence included in the symbol sequence with the continuous symbol sequence. Control means,
An information transmission system comprising: Generating means for generating a multi-level symbol sequence transmitted using visible light as a transmission medium;
In the multi-value symbol sequence generated by the generating means, if there is a continuous symbol sequence that is a symbol sequence in which the same symbol value continues for a predetermined number or more, this continuous symbol sequence is assigned a predetermined number of symbol values. Control means for controlling the generating means to replace with a discontinuous symbol string that is not a continuous symbol string and add replacement rule information;
A symbol string generation device comprising: The continuous symbol sequence has a plurality of types of patterns,
The symbol sequence according to claim 2, wherein the control unit causes the generation unit to replace the continuous symbol sequence with the non-consecutive symbol sequence according to a replacement rule corresponding to the plurality of types of patterns. Generator.   4. The symbol string generation device according to claim 3, further comprising storage means for storing the plurality of types of patterns and the replacement rule in association with each other.   5. The symbol string generation device according to claim 3, wherein the replacement rule information is a symbol string having a predetermined length indicating the replacement rule. The symbols constituting the symbol row are any of a plurality of colors whose hues are separated by the same distance from each other,
6. The symbol string generation device according to claim 2, further comprising an output unit that outputs a symbol string generated by the control unit to the device that emits light of a plurality of types of colors. An acquisition means for acquiring a symbol string transmitted using visible light as a transmission medium;
Control means for performing control to replace the non-consecutive symbol sequence included in the symbol sequence with a continuous symbol sequence when the replacement rule information is present in the symbol sequence acquired by the acquisition unit;
A symbol string decoding apparatus comprising: The continuous symbol sequence has a plurality of types of patterns,
8. The control unit according to claim 7, wherein the control unit performs control to replace the non-consecutive symbol sequence with the continuous symbol sequence with respect to the obtaining unit according to a replacement rule corresponding to the plurality of types of patterns. Symbol sequence decoding apparatus.   9. The symbol string decoding apparatus according to claim 8, further comprising storage means for storing the plurality of types of patterns and the replacement rule in association with each other.   10. The symbol string decoding apparatus according to claim 8, wherein the replacement rule information is a symbol string having a predetermined length indicating the replacement rule. The symbols constituting the symbol row are any of a plurality of colors whose hues are separated by the same distance from each other,
The symbol string decoding device according to claim 7, further comprising an input unit that inputs the symbol string from the device that receives the light of the plurality of types of colors. Computer
Generating means for generating a multi-level symbol sequence transmitted using visible light as a transmission medium;
In the multi-value symbol sequence generated by the generating means, if there is a continuous symbol sequence that is a symbol sequence in which the same symbol value continues for a predetermined number or more, this continuous symbol sequence is assigned a predetermined number of symbol values. Control means for controlling the generating means to replace with a discontinuous symbol string which is not a continuous symbol string and add replacement rule information;
Program to function as. Computer
An acquisition means for acquiring a symbol string transmitted using visible light as a transmission medium;
Control means for controlling the acquisition means to replace a non-consecutive symbol sequence included in the symbol sequence with a continuous symbol sequence when there is substitution rule information in the symbol sequence acquired by the acquisition unit;
Program to function as. Generating means for generating a multi-level symbol sequence transmitted using visible light as a transmission medium;
Control means for controlling the generating means to replace the multi-valued symbol string generated by the generating means with a non-consecutive symbol string that is a symbol string in which the same symbol value does not continue for a predetermined number or more;
A symbol string generation device comprising: Computer
Generating means for generating a multi-level symbol sequence transmitted using visible light as a transmission medium;
Control means for controlling the generating means so as to replace the multi-valued symbol string generated by the generating means with a non-consecutive symbol string that is a symbol string in which the same symbol value does not continue for a predetermined number or more;
Program to function as.

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