JP3853331B2 - Digital information recording method - Google Patents

Description

  The present invention relates to a digital information recording method for recording digital information as a two-dimensional pattern on a recording surface.

  Japanese Patent Application Laid-Open No. 03-038791 discloses a technique for providing a positioning boundary using black squares adjacent to at least two sides of an information recording area.

  However, when the positioning boundary is provided using the black squares along the side of the information recording area in this way, it is necessary to use at least a square corresponding to the length of the side as the positioning boundary.

In particular, when a certain pattern (specific pattern) is arranged along the side of the information recording area, only a method of providing a positioning boundary outside the information recording area and only a portion that does not overlap with the specific pattern in the information recording area. A method of providing a positioning boundary can be considered. Compared to the latter method, the former method requires more cells to form the positioning boundary, and the latter method is advantageous in terms of storage efficiency. However, in the latter method, since the positioning boundary is in contact with the specific pattern, it may be difficult to search for the specific pattern.
Japanese Patent Laid-Open No. 03-038791

  Accordingly, an object of the present invention is to provide a digital information recording method that facilitates searching for a specific pattern along the side of the information recording area at the time of reading when the specific pattern is arranged along the side of the information recording area. There is to do.

  There are also problems from the following viewpoints.

(A) Segmentation When a large amount of data is to be recorded, it is generally performed by dividing into blocks for management and other purposes. When recording information in such block units, a technique of how to divide or identify blocks is important.

  In the case of two-dimensional information recording related to the present invention, for example, an example of a multistage barcode is given. Among the multi-stage barcodes, the code 49 and the code 16K are overlapped with barcodes and separated by horizontal lines. There is also known a method of distinguishing stages using different subsets for each stage, such as PDF417 (two-dimensional barcode).

  In addition, a technique of arranging a plurality of symbols to represent one piece of information, for example, obtaining data by arranging barcodes and reading them in order, can be regarded as a kind of division in units of blocks.

  The present applicant has previously disclosed a technique for performing encoding in block units in Japanese Patent Application No. 6-070911, and further, in Japanese Patent Application No. 6-185858, image data is virtually set by setting a rectangular window. Has been disclosed. In these examples, there are no dividing lines between blocks, and the same subset is used for encoding, but recording is performed so that no more than a certain number of cells with the same value continue, and the boundaries of the cells are recognized. Thus, reading is performed in units of blocks.

  In the case where digital information is recorded by arranging two-dimensional matrices in this way, there are some problems when trying to apply the example of block unit coding shown as the prior art.

  First, in the case of a system in which a dividing line is provided, a certain amount of width is required to recognize the dividing line by the reading device. As data is recorded at a higher density and the size of the cell is reduced, the ratio of the dividing line in the recording surface increases, and the storage efficiency becomes worse. In particular, in the code 49 and the code 16K, the dividing line has a length from the end of the recording surface to the end, and therefore the proportion of the recording surface in the recording surface cannot be ignored.

  Similarly, in the case of a system in which symbols (barcodes) are arranged, there is a problem that a portion of a quiet area between symbols cannot be used for data recording.

  In addition, when the subset used for encoding is changed for each block (example of PDF417), or a subset that is easy to read is selected (example of the technique previously proposed by the applicant), it is separated between blocks. Control information for reading lines and quiet areas is not required. However, since one bit of data cannot be simply replaced with one black and white at the time of encoding, there is still a problem that the storage efficiency is lowered.

  Accordingly, an object of the present invention is to provide a digital information recording method capable of efficiently using a recording surface by setting an information recording area as a combination of segments which are areas represented in synchronization with a predetermined pattern. It is in.

  Another object of the present invention is to provide a digital information recording method capable of setting an information recording area in a free shape.

(B) Digital Information Decoding Method and Decoding Device When reading two-dimensionally recorded information as image information, the information recording area becomes large and may not be able to be loaded into the memory device of the reading device at one time. In addition, when the entire large information recording area recorded by the digital recording method with the two-dimensional grid arrangement is read using a CCD camera or the like, the number of CCD elements corresponding to one square is reduced, There is a problem that information cannot be read correctly.

  A technique for enlarging an image using an optical system when reading information recorded two-dimensionally using a CCD camera or the like is already known. For example, Japanese Patent Application Laid-Open No. 5-94561 discloses a method of reading a symbol such as a barcode by enlarging it to an appropriate magnification using an optical system. However, this technique presupposes that the entire image of the recording surface exists on the image sensor even after it has been enlarged (however, regarding the barcode, it is known that the entire image of the symbol cannot be developed on the image sensor). This suggests that barcode information can be read by using the automatic barcode restoration function.

  Accordingly, a further object of the present invention is to provide a digital information decoding method and a decoding device that can easily read out the recorded information recorded by the digital information recording method in units of segments.

(C) Use of margins on recording surface (i) Setting of frame information As described above, Japanese Patent Laid-Open No. 03-038791 discloses a black grid adjacent to at least two sides of an information recording area. A technique for providing a used positioning boundary is disclosed.

  However, when the positioning boundary is provided using the black squares along the side of the information recording area in this way, it is necessary to use at least a square corresponding to the length of the side as the positioning boundary.

  In particular, when a certain pattern (specific pattern) is arranged along the side of the information recording area, only a method of providing a positioning boundary outside the information recording area and only a portion that does not overlap with the specific pattern in the information recording area. A method of providing a positioning boundary can be considered. Compared to the latter method, the former method requires more cells to form the positioning boundary, and the latter method is advantageous in terms of storage efficiency. However, in the latter method, since the positioning boundary is in contact with the specific pattern, it may be difficult to search for the specific pattern.

  Accordingly, a further problem of the present invention is that frame information for determining the range of the information recording area can be provided in the recording surface when a specific pattern is arranged along the side of the information recording area, and at the time of reading It is an object of the present invention to provide a digital information recording method that facilitates searching for a specific pattern along the side of an information recording area.

(Ii) Setting of readable characters, etc. Japanese Patent Laid-Open No. 03-038791 shows an example in which symbols that can be read not only by a machine but also by human eyes can be recorded on a recording surface. Yes. Examples of information that can be read by humans include alphabets, numbers, and Morse codes. However, it is not described for what purpose it can be used other than being readable by humans.

  However, as far as this example is concerned, the information contained in the symbol is only information that can be read by humans (mainly digital information representing analog information), and information that can be read by humans. It is difficult to say that a technique for mixing digital information that can be recognized by a reading device in one symbol is disclosed.

  Accordingly, a further object of the present invention is to include information useful for reading or information that can be recognized by humans by using segments and areas that are not used as specific patterns when the recording surface is divided into segments. It is an object of the present invention to provide a digital information recording method capable of performing the above.

(Iii) About the setting of information for discriminating the top, bottom, left, and right of the recording surface Further, the problem of the present invention is to use segments and areas that are not used as specific patterns when dividing the information recording area into segments, It is an object of the present invention to provide a digital information recording method that includes information that allows a human to visually recognize or to discriminate between the top, bottom, left, and right sides inside the reader.

(Iv) Setting of quiet area and clock information Further, an object of the present invention is to use a region that is not used as a segment and a specific pattern when a recording surface is divided into segments, and to determine a predetermined position from the recording surface. It is an object of the present invention to provide a digital information recording method that includes information that makes it easier to extract a specific pattern arranged on the screen.

(D) Bar Code and Matrix Code A method of recording digital information by arranging a matrix in a two-dimensional manner enables higher density recording than a one-dimensional bar code. However, in the case of two-dimensional information recording in units of cells, the recorded information cannot be read correctly only by changing the value of one cell. On the other hand, a one-dimensional barcode has a small amount of information that can be recorded, but has higher redundancy than information recording with a two-dimensional grid arrangement, and can be read correctly even when it is partially collapsed. There are many cases where this is possible.

  Therefore, a further object of the present invention is to provide a digital information recording method having both the advantages of a highly redundant one-dimensional barcode and the information recording of a two-dimensional grid arrangement capable of high-density recording. There is.

  Japanese Patent Laid-Open No. 6-44397 discloses a technique for reading a one-dimensional code (bar code) using a device that reads a two-dimensional code. The one-dimensional code is taken in as two-dimensional bitmap data, recognized as a barcode, and decoded. However, the one-dimensional code and the two-dimensional code read by this apparatus are recorded in completely different areas, and the recording method is such that the one-dimensional code and the two-dimensional code are mixedly recorded in the same information recording area. Is not known. In addition, this apparatus cannot distinguish whether the information is a two-dimensional code or a one-dimensional code when the pattern of the two-dimensional grid is exactly the same as the barcode. In order to distinguish, a two-dimensional code having a format (format) that does not have the same arrangement as the barcode must be adopted, and the format (format) of the two-dimensional code is extremely restricted.

(E) Index information When an information recording area is configured by combining a plurality of segments, additional information such as the array state of the segments or the format of data recorded in the segments is used as index information of the data. Let's say.

  Japanese Patent Application Laid-Open No. 2-173879 discloses a technique for expressing information related to the data size in the main scanning direction by providing one format mark for eight meshes corresponding to bits. Thus, data can be read even when the data width in the main scanning direction varies depending on the recording medium.

  As described above, it is possible to perform efficient reading by knowing information related to data arrangement before reading original recording information.

  Similarly, when an information recording area is configured by combining a plurality of segments, the number of segments of the information recording area or how the segments are arranged before the original recording information is read ( Knowing the number of vertical and horizontal segments, etc. enables efficient reading.

  Also, before reading the original recording information, the length of the data recorded in the information recording area, the type of error correction code added to the data or the type of interleaving, etc. By knowing the information first, it is possible to read efficiently.

  Japanese Laid-Open Patent Application No. 02-244293 discloses a technique for recording important information in the central part of a substrate that is relatively less susceptible to contamination. However, this technique has an effect that it is hardly affected by dirt, but it is not advantageous when it is desired to read information prior to other information such as index information.

  Therefore, a further object of the present invention is to provide a digital information recording method that can easily obtain index information relating to a segment or recorded information recorded in the segment before reading the original recorded information. is there. It is another object of the present invention to provide a digital information recording method capable of obtaining index information without any trouble even when index information at one place is crushed.

In order to solve the above-mentioned problems, the digital information recording method of the present invention is a virtual information recording area virtually arranged in a flat recording surface, and virtually has a matrix-like parallelogram cell corresponding to the bit. The optically recognizable bright or dark mark corresponding to the digital information to be recorded in each cell is given according to the digital information to be recorded in units of each cell, and the above-mentioned recording should be performed. A digital information recording method for recording digital information as a two-dimensional pattern, wherein the mark is attached in a predetermined pattern to a plurality of cells connected to a specific shape so as to indicate a position in the recording surface. A plurality of specific patterns are arranged in parallel in the information recording area with a predetermined interval in the row direction and the column direction, and the specific patterns arranged in the row direction or the column direction are reduced in the information recording area. Kutomo 1 is arranged at a position protruding outside the information recording area with respect to the sides, the bay-shaped region surrounded by the side facing the sides and the protruding specific pattern of the information recording area, bounding line for the specific pattern The frame pattern extending along the line is arranged with a gap corresponding to one square with respect to the opposite sides of the protruding specific pattern .
The “parallelogram” is a concept including a square and a rectangle.

  In the digital information recording method of the present invention, the specific pattern arranged in the row direction or the column direction is arranged at a position that protrudes to the outside with respect to at least one side of the information recording area. Makes it easier to find. For example, if “black” information is obtained by performing a search along the side of the information recording area, the specific pattern can be recognized by regarding the “black” as a part of the specific pattern. Therefore, the specific pattern arranged at the protruding position is easily recognized.

Further, in this digital information recording method, a frame pattern extending along a circumscribing line with respect to the specific pattern is disposed in a bay area surrounded by the side of the information recording area and the opposite side of the protruding specific pattern. Therefore, at the time of reading, the range of the information recording area on the recording surface is easily detected. Further, since the frame pattern is arranged with a gap of at least one square with respect to the opposite sides of the protruding specific pattern, the search for the protruding specific pattern is not hindered. For example, assuming that the protruding portion of the frame pattern and the specific pattern is “black”, when the search is performed along the side of the information recording area, each time the black information and the white information are switched, the specific pattern, It can be considered that the gap for the first grid, the frame pattern, the gap for the first grid, and the specific pattern appear in order. Therefore, the search for the specific pattern arranged at the protruding position is not hindered, and the search for the specific pattern is easily performed.

In another aspect, the digital information recording method of the present invention is a virtual information recording area of a substantially rectangular shape provided in a flat recording surface, in which a matrix-like parallelogram cell corresponding to a bit is virtually displayed. The optically recognizable bright or dark mark corresponding to the digital information to be recorded in each cell is given according to the digital information to be recorded in units of each cell, and the above-mentioned recording should be performed. A digital information recording method for recording digital information as a two-dimensional pattern, wherein the mark is attached in a predetermined pattern to a plurality of cells connected to a specific shape so as to indicate a position in the recording surface. A plurality of specific patterns are arranged in parallel in the information recording area with predetermined intervals in the row direction and the column direction, and the specific patterns arranged in the row direction or the column direction are reduced in the information recording area. Also arranged at a position protruding outside the said information recording area for one side, the bay-shaped region surrounded by the side facing the sides and the protruding specific pattern of the information recording area, the sides of the information recording area A clocking pattern with alternately different marks is arranged with respect to the direction along.

In the digital information recording method according to the present invention , since the clocking pattern with the marks that are alternately different with respect to the direction along the side of the information recording area is arranged in the bay-shaped area, the information recording is performed at the time of reading. It becomes easy to find another specific pattern from one specific pattern that protrudes from the side of the region. Further, it is possible to accurately obtain the position of each cell in the information recording area based on the clocking pattern.

  In general, in order to find an adjacent specific pattern belonging to the same row or column based on the position of a specific pattern, information on the size of the cell is obtained from the specific pattern, and the position is separated by a known cell. A technique for inferring the existence of an adjacent specific pattern is taken. However, in this method, since a distant position is predicted, there is a possibility that a shift occurs with the search. On the other hand, if the next specific pattern is searched while following the clocking pattern and sequentially correcting, the expected position of the adjacent specific pattern can be set accurately, and the adjacent specific pattern can be easily found. it can.

  In another aspect, in the digital information recording method of the present invention, a matrix-like cell corresponding to a bit is virtually set on a flat recording surface, and according to the digital information to be recorded in each of the cells A digital information recording method for recording a digital information to be recorded as a two-dimensional pattern by providing an optically recognizable mark, and connecting the information to a specific shape so as to indicate a position in the recording surface A specific pattern formed by attaching the mark in a predetermined pattern to a plurality of cells, and a plurality of cells connected in a rectangular shape in the vertical and horizontal directions, and the dimensions of the specific pattern in the vertical and horizontal directions A rectangular block having a larger dimension is set, a segment in which the specific pattern is overlapped or circumscribed on the rectangular block in a grid unit is set, and the segment is duplicated on the recording surface. An information recording area where the two-dimensional pattern should be expressed is set without gaps, and unit information is created by dividing the digital information to be recorded according to the number of segments. The unit information is allocated in correspondence with the segment, and the unit information is recorded in a cell other than the cell occupied by the specific pattern in the segment.

  In the digital information recording method of the present invention, unit information is created by dividing the digital information to be recorded according to the number of segments, and the unit information is allocated and recorded corresponding to the segments. It becomes possible to manage in segment units. For example, when information recorded in a specific segment is erroneously read, only that segment can be read again. Alternatively, it is possible to limit the influence of reading errors to only one segment.

  In addition, by setting the specific pattern small, it is possible to use the information recording area more efficiently than when using a dividing line or the like.

  The digital information recording method of one embodiment creates a divided pattern by dividing the specific pattern in at least one direction of the vertical direction and the horizontal direction in each segment, and the divided pattern is divided into the rectangular blocks. When the segments are arranged at positions that are inscribed in the four corners, the specific pattern is synthesized by the division pattern arranged in the adjacent rectangular block on the boundary point where the four rectangular blocks abut each other at the vertex It is characterized by having been made.

  According to the digital information recording method of this embodiment, as a result, the specific pattern is arranged at the vertex of the rectangular block that is a component of the segment. Therefore, when the recorded information is read, a range defined by four adjacent specific patterns arranged at positions corresponding to the vertices of the rectangular block can be extracted as one segment. Further, the position of each cell in the segment can be obtained with reference to the positions of the four specific patterns. In this case, the reading accuracy is improved as compared with the case where the position of one specific pattern is used as a reference. In addition, the data of an arbitrary cell in the segment can also be read out using the position information of the same set of four specific patterns.

  Also, the digital information recording method of one embodiment can synthesize the specific pattern by combining the segment existing along the outer periphery of the information recording area with the division pattern arranged on the outer peripheral side of the segment. The division pattern is circumscribed and added.

  In the digital information recording method of this one embodiment, the segment that can be combined with the segment pattern arranged on the outer periphery side of the segment is combined with the segment existing along the outer periphery of the information recording area. Since the pattern is circumscribed and added, the specific pattern is arranged in a complete manner on the outer peripheral side of the segment. Therefore, it is possible to accurately determine the position of each cell in the segment with reference to the positions of the four specific patterns synthesized at the four corners of the segment that exists along the outer periphery of the information recording area. It becomes. Therefore, the reading accuracy is increased.

  Also, the digital information recording method according to an embodiment is characterized in that number information indicating the order of assigned unit information is recorded in each segment.

  In the digital information recording method according to this embodiment, number information indicating the order of assigned unit information is recorded in each segment, and therefore, when the recorded information is read, a recording step is performed based on the number information. Thus, the unit information can be read from each segment in the same order as the unit information was recorded. Therefore, the original digital information can be easily restored. As a result, the information recording area can be set in a free shape at the recording stage.

  The digital information recording method according to an embodiment is characterized in that adjacent information indicating whether or not there is a segment adjacent to the segment is recorded in each segment.

  In the digital information recording method of this embodiment, since the adjacent information indicating whether or not there is a segment adjacent to the segment is recorded in each segment, when the recorded information is read, the adjacent information is recorded. Based on this, it is possible to read each segment sequentially while checking whether there is a segment adjacent to one segment. As a result, the information recording area can be set in a free shape at the recording stage.

  The digital information recording method according to an embodiment is characterized in that the segments are arranged according to a predetermined arrangement rule including a direction and a number in which the segments are to be arranged.

  In the digital information recording method of this embodiment, the segments are arranged according to a predetermined arrangement rule including the direction and number in which the segments are to be arranged. Therefore, when the recorded information is read, the recording is performed based on the arrangement rule. It is possible to read unit information from each segment in the same order as the unit information is recorded in stages. Therefore, the original digital information can be easily restored.

  Here, the arrangement rule does not indicate how to arrange each segment, but rather indicates a general concept including the direction and number in which the segments should be arranged. For example, a rule such as setting the information recording area to a square or arranging 10 segments in the horizontal direction may be arranged in the next line adjacent to the line.

  Further, the digital information decoding method of the present invention is a digital information decoding method for reading the recorded information recorded by the digital information recording method, and the step of recognizing a portion corresponding to the corner of the information recording area on the recording surface Recognizing four specific patterns arranged at positions corresponding to the vertices of the rectangular blocks present at the corners of the information recording area, and one specified by the four specific patterns of the information recording area. In this segment, the process of reading the unit information assigned to the segment by decoding the pattern represented by the cell other than the cell occupied by the specific pattern, and corresponding to the vertex of the rectangular block adjacent to the one rectangular block Detecting four specific patterns arranged at a position to be detected, and the four specific patterns in the information recording area Accordingly, in the segment adjacent to the one segment defined above, the step of decoding the pattern attached to the grid other than the grid occupied by the specific pattern and reading the unit information assigned to the segment; A step of connecting unit information read from one segment and unit information read from a segment adjacent to the one segment.

  According to the digital information decoding method of the present invention, the recorded information recorded by the digital information recording method can be easily restored. In particular, since reading is performed in units of segments, the reading accuracy is higher than when reading and decoding the entire information recording area. Further, since reading is performed in segment units, there is an advantage that the memory capacity necessary for storing image information at the time of decoding is only one segment. This is because when the decoding for one segment is completed, the result is output, and the image information for the next segment may be stored (overwritten) in the image memory. In other words, even if the image memory capacity is constant, digital information recorded in a large area information recording area can be read. Note that when reading the entire information recording area as image information at once, a memory capacity corresponding to the image information of the entire information recording area is required.

  Also, processing such as reading error detection / error correction can be performed in segment units. In this case, surplus bits such as a checksum and CRC are added in segment units. In addition, shuffling processing for dispersing burst errors can be performed on a segment basis.

  Further, when a reading error occurs, it is possible to read only the target segment again. Also, in re-reading, the processing in the reading device, such as increasing the magnification of the CCD camera, and the processing at the time of analysis, such as using a more accurate analysis method for the read image, are different from the first method. Can be re-read using. At this time, if reading that is expected to be performed at high speed is used for the first reading and time is required for re-reading, but reading with higher accuracy is used, high-speed and reliable reading can be performed as a whole.

  The digital information decoding apparatus according to the present invention is a digital information decoding apparatus for reading the recorded information recorded by the digital information recording method, wherein the two-dimensional pattern recorded on the recording surface is opposed to the recording surface. The information recording on the recording surface based on the image information output by the reading means for outputting the image information representing the opposed portion, the recording surface and the reading means are relatively moved After recognizing the portion corresponding to the corner of the area, the four specific patterns arranged at the positions corresponding to the vertices of the rectangular blocks existing at the corner of the information recording area are recognized, and the 4 of the information recording areas are recognized. Within one segment defined by one specific pattern, the pattern represented by the cells other than the cells occupied by the specific pattern is decoded and assigned to this segment. The read unit information is read, and then the reading means is scanned to change the reading range on the recording surface, and four units arranged at positions corresponding to the vertices of the rectangular blocks adjacent to the one rectangular block are arranged. A specific pattern is detected, and a pattern attached to a cell other than the cell occupied by the specific pattern is decoded in a segment adjacent to the one segment defined by the four specific patterns in the information recording area. And reading the unit information assigned to the segment, and controlling means for controlling the unit information read from the one segment and the unit information read from the segment adjacent to the one segment. It is characterized by that.

  According to the digital information decoding apparatus of the present invention, the digital information recording method can be implemented, and therefore the operational effects of the digital information recording method can be achieved.

  Further, in the digital information decoding apparatus according to one embodiment, the reading unit includes an optical system capable of setting a magnification for converting the two-dimensional pattern recorded on the recording surface into the image information, and the control unit includes At least the optical system between the step of recognizing a portion corresponding to the corner of the information recording area on the recording surface and the step of reading unit information from the segments defined by the four specific patterns in the information recording area It is characterized in that control is performed to change the magnification.

  In the information decoding apparatus of this embodiment, the control means recognizes a portion corresponding to a corner of the information recording area on the recording surface, and a unit from a segment defined by the four specific patterns in the information recording area. Since control for changing at least the magnification of the optical system is performed between the steps of reading information, the accuracy of the image information captured by the optical reading unit can be set to a level suitable for each step.

  In other words, in the former process, image information is captured with a rough accuracy that allows the entire information recording area to enter the field of view, and a portion corresponding to a corner of the information recording area is recognized. In the latter process, the magnification of the optical system is further increased. Thus, it is possible to perform processing such as adjusting the image accuracy to detect the mark attached to each cell in the segment and reading the unit information from the segment defined by the four specific patterns. As a result, reading is performed at high speed and reading accuracy is further increased.

  The digital information recording method according to an embodiment includes a segment that exists along the outer periphery of the information recording area, a segment that exists at a corner of the information recording area, and a segment that is not included in the segment of the information recording area. And the presence or absence of a pattern in the bay-shaped region surrounded by the added divided pattern, or different patterns are arranged in the bay-shaped region.

  In the digital information recording method of this one embodiment, the segment existing along the outer periphery of the information recording area, the segment existing in the corner of the information recording area, and the other segments, and the side of the information recording area Since the presence or absence of the pattern in the bay-shaped region surrounded by the added divided pattern is changed, or different patterns are arranged in the bay-shaped region, the segments present in the corners of the information recording region at the time of reading are Easy to recognize.

  Whether or not the segment exists in the corner of the information recording area can be a criterion for determining the end condition when the recorded digital information is read in units of segments.

  In another aspect, the digital information recording method of the present invention virtually sets a matrix cell corresponding to a bit in an information recording area provided in a planar recording surface, and A digital information recording method for recording an optically recognizable mark according to digital information to be recorded and recording the digital information to be recorded as a two-dimensional pattern, in a part of the information recording area, Characters or symbols that humans can understand as they are are expressed in units of the cells.

  In the digital information recording method according to the present invention, characters or symbols that can be understood by humans are expressed in a part of the information recording area in units of the cells, so that information that can be directly understood by humans in one information recording area. And digital information that cannot be directly understood can be recorded simultaneously. Further, at the time of reading, it is possible to read both pieces of information using the same decoding device and know what pattern each information is composed of.

  Examples of characters or symbols that humans can understand as they are include information necessary for reading, such as instructions for the direction of insertion into the scanner, information on the contents of recorded digital information (such as file names), and the like. .

  In another aspect, the digital information recording method of the present invention virtually sets a matrix cell corresponding to a bit in an information recording area provided in a planar recording surface, and A digital information recording method for recording an optically recognizable mark according to digital information to be recorded and recording the digital information to be recorded as a two-dimensional pattern, the position being indicated on the recording surface A specific pattern formed by attaching the mark in a predetermined pattern to a plurality of cells connected to a specific shape is arranged in the information recording area, and the specific pattern is arranged in the information recording area. Characters or symbols that can be visually recognized by human beings are expressed in a part of the area excluding the area in units of the cells.

  In the digital information recording method of the present invention, since the specific pattern is arranged in the information recording area, the position of each cell in the information recording area can be accurately obtained based on the specific pattern at the time of reading. The accuracy can be increased. In addition, similarly to the above, information that can be directly understood by humans and digital information that cannot be directly understood can be simultaneously recorded in one information recording area.

  In another aspect, the digital information recording method of the present invention virtually sets a matrix cell corresponding to a bit in an information recording area provided in a planar recording surface, and A digital information recording method for recording an optically recognizable mark according to digital information to be recorded and recording the digital information to be recorded as a two-dimensional pattern, the position being indicated on the recording surface A specific pattern formed by attaching the mark in a predetermined pattern to a plurality of cells connected to a specific shape is arranged in the information recording area, and the specific pattern is arranged in the information recording area. A pattern representing the top, bottom, left, right, and front and back of the recording surface is arranged in a part of the area excluding the area.

  In the digital information recording method of the present invention, the pattern representing the top, bottom, left, and right of the recording surface is arranged in a part of the information recording area excluding the area where the specific pattern is arranged. Therefore, the position of each cell in the information recording area can be accurately obtained, and the reading accuracy can be improved. In addition, since the pattern representing the top / bottom / left / right and front / back of the recording surface is arranged in a part of the information recording area excluding the region where the specific pattern is disposed, the top / bottom / left / right and front / back of the recording surface can be easily read. Is determined.

  For example, when the recording surface is optically read using a CCD camera or the like, the reading surface determines the top, bottom, left, right and back of the recording surface based on the pattern, regardless of the reading direction. In particular, assuming that the above-described patterns representing the top, bottom, left, right, and front and back can be understood as they are, it is possible for a human to visually distinguish the top, bottom, left, right, and front and back of the recording surface. Therefore, even when the recording surface is optically read using a paper feed type scanner, it can be inserted into the scanner in the correct orientation.

  In another aspect, the digital information recording method of the present invention virtually sets rectangular cells arranged in a matrix corresponding to bits in an information recording area provided in a planar recording surface, A digital information recording method for recording an optically recognizable mark corresponding to digital information to be recorded on each cell and recording the digital information to be recorded as a two-dimensional pattern. A bar code that constitutes a bar and a space in units of the grid is recorded in the section.

  In the digital information recording method of the present invention, a bar code as a one-dimensional code and a two-dimensional pattern formed by adding marks to each cell are recorded in the same information recording area in units of cells. Since both are in units of cells, the same printing control method can be applied during printing. Also, at the time of reading, it is possible to decode both pieces of information using the same decoding device. If the barcode part can be extracted from the captured image information, the barcode part can be decoded by one-dimensional scanning.

  Moreover, since the bar and space which comprise the said barcode are comprised using a some square, redundancy is large compared with the pattern in which one square represents one value. Therefore, it is possible to form a portion (barcode portion) in which reading errors are unlikely to occur in the information recording area. Such a portion where reading errors are unlikely to occur is suitable for recording important information such as index information.

  The digital information recording method according to an embodiment includes a specific pattern formed by attaching the mark in a predetermined pattern to a plurality of cells connected to a specific shape so as to indicate a position in the recording surface. The information recording area is arranged in an area other than the area occupied by the barcode.

  In the digital information recording method of this embodiment, since the specific pattern is arranged in the information recording area, the position of each cell in the information recording area can be accurately obtained based on the specific pattern at the time of reading. The reading accuracy can be increased. In addition, the same effects as described above can be achieved. As described above, when the specific pattern arranged in the row direction or the column direction is arranged at a position protruding to the outside with respect to at least one side of the information recording area, the side of the information recording area and the specific pattern protruding above By recording the bar code in a bay area surrounded by opposing sides, the recording surface can be used effectively.

  Also, the digital information recording method of one embodiment includes the bay-shaped region surrounded by the side of the information recording region and the added division pattern, the segment arrangement state, and the digital information recorded in the information recording region. Index information representing at least one of an information size, an encoding method and an error correction method for unit information recorded in the segment is recorded.

  In the digital information recording method of this embodiment, since the index information is recorded in the bay area surrounded by the side of the information recording area and the added division pattern, the information recorded in the segment is read at the time of reading. Reading the index information prior to reading enables efficient reading. For example, a memory buffer necessary for decoding can be secured by knowing in advance the digital size recorded in the information recording area as index information at the time of reading. Also, efficient reading is possible by knowing in advance the arrangement state of the segments, for example, the number of segments and the number of vertical x horizontal.

  In addition, since the error correction method (code) and interleave method added to the data can be recorded for each record carrier, even if different error correction methods and interleave methods are used for each record carrier, no confusion occurs during reading. This is because the error correction method (code) and the interleaving method can be known in advance from the recorded index information.

  Moreover, since the index information is recorded in the bay area and not recorded in the segment of the information recording area, the amount of information that can be recorded in the information recording area is not reduced by recording the index information.

  The digital information recording method according to an embodiment includes a segment existing at a specific position in the information recording area, an arrangement state of the segments, a size of digital information recorded in the information recording area, and a size in the segment. Index information representing at least one of an encoding method and an error correction method for the recorded unit information is recorded.

  In the digital information recording method of this embodiment, since the index information indicating the arrangement state of the segments is recorded in the segment existing at a specific position in the information recording area, the segment is read first at the time of reading. Thus, it is possible to know the arrangement state and the like of segments existing at other positions. Therefore, efficient reading is possible.

  The digital information recording method according to an embodiment is characterized in that the information recording area is set in a substantially rectangular shape, and the index information is recorded in segments present at four corners of the information recording area.

  In the digital information recording method of this embodiment, the index information is recorded in the segments existing at the four corners of the information recording area. Since the segments present at the four corners of the information recording area can be found more easily than the segments present at other locations, the index information can be easily obtained prior to reading the segments present at the other locations. To be acquired. Therefore, efficient reading is possible.

  In another aspect, in the digital information recording method of the present invention, a matrix-like cell corresponding to a bit is virtually set on a flat recording surface, and according to the digital information to be recorded in each of the cells A digital information recording method for recording an optically recognizable mark and recording the digital information to be recorded as a two-dimensional pattern, wherein a rectangular small block consisting of a plurality of connected cells is set and the recording is performed By arranging a plurality of the small blocks on the surface without gaps, an information recording area for expressing the two-dimensional pattern is set, and the digital information to be recorded is divided according to the number of the small blocks to obtain unit information. In the digital information recording method for creating and allocating and recording this unit information corresponding to each of the small blocks, the small block existing at a specific position in the information recording area, Index information indicating at least one of the arrangement state of the small blocks, the size of the digital information recorded in the information recording area, the encoding method and the error correction method for the unit information recorded in the small block It is characterized by recording.

  In the digital information recording method of the present invention, since the index information indicating the arrangement state of the small blocks is recorded in the small block existing at the specific position in the information recording area, the small block is read first at the time of reading. As a result, it is possible to know the arrangement state and the like of the small blocks existing at other positions. Therefore, efficient reading is possible.

  The digital information recording method according to an embodiment is characterized in that the information recording area is set to a substantially rectangular shape, and the index information is recorded in small blocks existing at four corners of the information recording area.

  In the digital information recording method of this embodiment, the index information is recorded in small blocks existing at the four corners of the information recording area. Since the small blocks existing at the four corners of the information recording area can be found more easily than the small blocks existing at other positions, the index information is read prior to reading the small blocks existing at the other positions. And easily acquired. Therefore, efficient reading is possible.

  Also, the digital information recording method of one embodiment is characterized in that the same index information is recorded in each of the plurality of bay-shaped regions, the segments, or the small blocks.

  In the digital information recording method of this embodiment, since the same index information is recorded in each of the plurality of bay-shaped regions, the segments, or the small blocks, the index information recorded in one place is erroneously read at the time of reading. However, it is possible to read out correct index information from another location.

  For example, consider the case where the same index information is recorded in four segments existing at the four corners of the information recording area. Normally, the index information of the upper left corner segment is used, but there are cases where the upper left corner segment cannot be recognized due to a specific pattern in the upper left corner being crushed. In such a case, index information can be obtained by reading the upper right corner segment. If the number of segments arranged in the horizontal direction can be obtained from the index information obtained from the upper right corner segment, the upper left corner segment can be read again by complementing the specific pattern in the upper left corner.

  Hereinafter, the present invention will be described in detail with reference to examples.

(1) Basic Configuration of Digital Information Record Carrier FIG. 1 shows an embodiment of a digital information record carrier in the field using the present invention, and FIG. 2 schematically shows this record carrier.

  On the recording surface 20 of this digital information record carrier, matrix-like square cells corresponding to the bits of the digital information are virtually set, and “0” is set as an optically recognizable mark in each cell. White (bright) or black (dark) representing “1” is added (black is hatched for convenience). Thereby, digital information is recorded on the recording surface 20 as a two-dimensional pattern.

  In the information recording area 23 in which information is actually recorded in the recording surface 20, a specific pattern is formed in a plurality of cells connected to a specific shape in the gap of the area 21 representing the original recording information. A plurality of specific patterns 22 with black and white are arranged. In this example, in the rectangular information recording area 23, a total of 12 specific patterns 22 of vertical 4 × horizontal 3 are arranged in a matrix at regular intervals in the vertical and horizontal directions. As can be clearly understood from FIG. 2, the ten specific patterns 22 belonging to the uppermost, lowermost, left, and right columns in the arrangement of the specific patterns 22 are arranged along the outer periphery of the information recording area 23, and the remaining two patterns. The specific pattern 22 is arranged in the inside (near the center) separated from the outer periphery of the information recording area 23. In this example, the specific pattern 22B shown in FIG. 7 is adopted as the specific pattern 22 (the specific pattern itself will be described in detail later).

  As described above, when the specific pattern 22 is arranged inside the information recording area 23 apart from the outer periphery, when the recorded digital information is read, the digital information is read out even if the recording surface 20 is slightly distorted. Can be read accurately.

  For example, as shown in FIG. 3 (b), when the clocking information 31 is simply provided along the outer periphery of the information recording area 23 as in the prior art, if the recording surface 20 is distorted, the outer periphery of the information recording area 23 For example, the information of the cell in the fifth row and the fourth column is scheduled to be read, but the cell information in the sixth row and the fifth column may be erroneously read. On the other hand, when the specific pattern 22 is arranged inside the information recording area 23 as described above, even if the recording surface 20 is distorted as shown in FIG. In accordance with the distortion, the specific pattern 22 moves from the original position 53 to the position 54, for example. Therefore, when information on a certain cell (originally located at the position 55) is read, the actual position 56 of the cell is known based on the movement amount 51 (indicated by an arrow in the figure) of the specific pattern 22 in the vicinity. be able to. Therefore, the information recorded in the cell can be read accurately.

  The problem here is the difference between the movement amount 52 of the cell to be read and the movement amount 51 of the specific pattern 22 in the vicinity thereof. If this difference is large (for example, when this difference exceeds the first square), a reading error occurs, but the interval between the specific patterns 22 and 22 is narrowed to bring the specific pattern to be read closer to the specific pattern. Therefore, such reading errors can be reduced.

  Conversely, based on the amount of movement of the specific pattern 22, the interval between the specific patterns 22 and 22 should be set so narrow that the misalignment of the cells to be read can be corrected. However, if the interval between the specific patterns 22 and 22 is too narrow, the number of the specific patterns 22 in the information recording area 23 increases so that the amount of information that can be recorded decreases. Therefore, from both viewpoints, the interval between the specific patterns 22 and 22 is set to an appropriate value.

  When information is to be read from this information record carrier using, for example, a line sensor or a CCD camera, distortion tends to occur at both ends of the line sensor and at the periphery of the visual field of the CCD camera. In such a case, as shown in FIG. 4, the specific pattern is arranged at a high density around the information recording area 23. That is, according to the characteristics of the reading device, the specific patterns 22 are arranged at a high density where a relatively large reading distortion is likely to occur. Thereby, reading errors can be reduced.

  Conversely, as shown in FIG. 5, when the specific pattern 22 is arranged inside the information recording area 23 and the clocking information 31 is provided around the information recording area 23, the specific pattern 22 is the clocking information. 31 complementary roles are expected. Therefore, it is desirable to arrange the specific patterns 22 at a high density in a portion that is prone to error in reading based only on the clocking information 31, that is, in the center of the information recording area 23.

  In these cases, the vertical and horizontal intervals between the specific patterns 22 and 22 may be the same or different.

  However, when the interval between the specific patterns 22 and 22 is changed in the information recording area 23, when reading is performed, the arrangement of the specific pattern 22 can be known in advance or can be known at the first stage of the reading process. It is necessary to do so. In order to know the arrangement of the specific pattern 22 at the first stage of the reading process, for example, the arrangement of the uppermost specific pattern 22 is determined, and the arrangement of the specific pattern 22 from the grid near the uppermost specific pattern 22 is determined. Information should be readable.

  When the decoding device knows the arrangement of the specific pattern 22 in advance, the specific pattern 22 does not need to be in contact with the outer periphery of the information recording area 23, and the specific pattern 22 needs to be arranged in a lattice pattern. Nor. The specific pattern 22 can be freely arranged.

(2) About preferred examples of specific pattern The following (a) to (e) are listed as conditions to be provided for the specific pattern 22 to be preferable. That is,
(A) having a characteristic (specific black and white pattern) that can be easily found in the information recording area 23;
(A) The number of cells constituting the cell is relatively small,
(C) When the same or similar pattern appears in the vicinity as the original recorded information, it is difficult to overlap with the appearing pattern.
(D) Being less susceptible to smudges and ink bleed during printing,
(E) The algorithm for finding it is simple.

  FIG. 6 shows a preferred example 22 </ b> A of the specific pattern 22. The specific pattern 22A includes a central closed region 44 composed of 4 rows of 2 rows × 2 columns with white and a ring portion composed of 12 cells with black surrounding the periphery. 45. As a whole, it is a square block including a total of 16 squares of 4 rows × 4 columns.

  FIG. 7 shows another preferable example 22B of the specific pattern 22. The specific pattern 22B includes a central portion 41 made up of one square with black, a first annular portion 42 made up of eight squares with white surrounding the circumference, and further The second annular portion 43 is composed of 16 squares with black surrounding the periphery. As a whole, it is a square block including a total of 25 cells of 5 rows × 5 columns.

  8A to 8G show various examples 22C to 22I of the specific pattern 22. FIG.

  The specific pattern 22C shown in FIG. 6A is composed of a central portion made up of a single cell marked with black and an annular portion made up of eight squares attached with white surrounding the periphery thereof. It is configured. As a whole, it is a square block including a total of 9 squares of 3 rows × 3 columns.

  Further, the specific pattern 22D shown in FIG. 5B is a square block including a total of 25 squares of 5 rows × 5 columns, and black and white are alternately attached to the squares in the block. It has a checkered pattern.

  Further, the specific pattern 22E shown in FIG. 5C is a square block including a total of 25 squares of 5 rows × 5 columns, and black is added to the diagonal squares in the block to form an X character. The pattern is shaped.

  In addition, the specific pattern 22F shown in FIG. 4D is a central closed region composed of 9 rows of 3 rows × 3 columns with white and 16 black with a circle surrounding the periphery. It is comprised with the cyclic | annular part which consists of a square. As a whole, it is a square block including a total of 25 cells of 5 rows × 5 columns.

  Further, the specific pattern 22G shown in FIG. 5E is obtained by removing the grids at the centers of the upper, lower, left and right sides of the specific pattern 22E shown in FIG.

  Further, the specific pattern 22H shown in FIG. 5F is a square block including a total of 35 squares of 5 rows × 7 columns, and the squares with black marks in the block are S-shaped patterns. I am doing.

  Further, the specific pattern 22I shown in FIG. 5G is composed of a central portion made up of one square with white and an annular portion made up of eight squares with black surrounding the periphery. It consists of and. As a whole, it is a square block including a total of 9 squares of 3 rows × 3 columns.

  As described above, various patterns can be adopted as the specific pattern 22, but the specific patterns 22 </ b> A and 22 </ b> B shown in FIGS. 6 and 7 are more preferable than the other specific patterns 22 </ b> C to 22 </ b> I. The reason will be described next in relation to the above conditions (a) to (e).

  (A) First, there is an advantage that it is relatively easy to extract the specific patterns 22A and 22B from the information recording area 23. The specific pattern 22D of the checkered pattern as shown in FIG. 8B is buried in the information recording area 23 and cannot be found, while the specific patterns 22A and 22B can be found by the naked eye. In particular, when it is known in advance that the specific patterns 22A and 22B are arranged in a lattice pattern, it can be found more easily.

  (B) Second, there is an advantage that the number of cells constituting the specific patterns 22A and 22B is relatively small, 16 for the specific pattern 22A and 25 for the specific pattern 22B.

  (C) Third, when the same pattern appears as the original recording information in the vicinity of the specific patterns 22A and 22B, there is an advantage that the specific pattern 22A or 22B and the pattern do not easily overlap.

FIG. 9 shows an example in which the same pattern appears as original recording information in the vicinity of the checkered pattern 22D shown in FIG. 8B. In the case of this specific pattern 22D, there is a possibility that the same pattern appears at a position shifted by the first grid in the vertical direction and the first grid in the horizontal direction. When calculated as the length 1 of one side of the square, the minimum distance between the specific pattern 22D and the same pattern is ^21/2 .

  On the other hand, FIG. 10 shows an example in which the same pattern appears as the original recording information in the vicinity when the specific pattern 22A is used. In the case of this specific pattern 22A, the same pattern can appear only at a position shifted by 3 squares vertically or horizontally. FIG. 11 shows an example in which the same pattern appears as the original recording information in the vicinity when the specific pattern 22B is used. In the case of this specific pattern 22B, the same pattern can appear only at a position shifted by 4 squares vertically or horizontally. As described above, the specific patterns 22A and 22B are relatively little overlapped even if the same or similar pattern appears as the original recording information in the vicinity thereof, and the positions are shifted to a certain extent. From this, it can be said that the specific patterns 22A and 22B are patterns that are relatively easy for the reader to distinguish from the original recorded information.

  A countermeasure when the specific pattern 22 and the same pattern overlap with each other will be described in detail in the section of a decoding method to be described later.

  (D) Fourth, the specific patterns 22A and 22B have an advantage that they are not easily affected by dirt or ink bleeding.

  Generally speaking, in printing on paper, black eyes spread due to ink bleeding and white eyes tend to erode. For example, in the specific pattern 22I shown in FIG. 8G, one white eye is surrounded by a black eye, but the white eye tends to be crushed. As shown in FIG. 12, when the influence of ink bleeding is calculated on the assumption that each side of the black eyelet 47 spreads 1.4 times, the area of the white eyelet 46 in the center of the specific pattern 22I is normal. Only 36% of the time.

  On the other hand, in the specific pattern 22A, as shown in FIG. 13, the area of the central closed region (four white eyes) 44 can be secured at 64% of the normal time. Further, in the specific pattern 22B, as shown in FIG. 14, the area of the first annular portion (eight white eyes) 42 can be secured to 60% of the normal time. In the case of the specific pattern 22A, as shown in FIG. 15, one of the four white eyes constituting the central closed region 44 is completely crushed due to dirt or the like (changed to black eyes). Even at this time, since the feature of “white closed region surrounded by a black frame” is retained, the influence of dirt can be avoided by adopting a reading method using this feature.

  (E) Fifth, the specific patterns 22A and 22B have an advantage that the reading algorithm is simple.

  As a general reading algorithm, a method is used in which the size of a cell is determined from the recording surface and cut out, and the value of each cut out cell (in this example, white or black) is examined. Therefore, when recognizing the specific pattern 22, a method of cutting out the cells constituting the specific pattern 22 and examining the values of all the cells included in the specific pattern 22 can be considered.

  On the other hand, a method of examining the specific pattern 22 without cutting out the cell unit is also conceivable. For example, in the case of the specific pattern 22B shown in FIG. 7, first, the central portion (black eyelet) 41 forms a closed region surrounded by the white eyelet, and the first annular portion (white eyelet) 42 is formed. It can be found by examining whether or not it constitutes a closed region surrounded by black squares. In the case of the specific pattern 22A shown in FIG. 6, it can be found by examining whether the central closed region 44 has an area equivalent to the fourth square. In either case, it is merely checked whether the read portion matches the characteristics of the specific patterns 22A and 22B, in other words, whether the necessary conditions of the specific pattern are satisfied, and does not check the value of each cell. . However, this method is sufficient for practical use. Even if another pattern is mistakenly recognized as a specific pattern, for example, after extracting all the specific patterns, check whether each specific pattern is arranged in a grid pattern, etc. Can ignore misrecognized ones. In addition, it is possible to perform a more accurate check only for a specific pattern that is likely to be erroneously recognized. Thus, the specific patterns 22A and 22B can be recognized by a simple algorithm.

  Thus, the specific patterns 22A and 22B have many advantages over other specific patterns and can be said to be preferable patterns.

(3) Recognition of Specific Pattern FIG. 16 shows an example of a processing flow for recognizing the specific pattern 22B shown in FIG.

  The recognition process is performed on the bitmap data read from the reading device.

  First, when the specific pattern 22B is arranged in the information recording area 23 according to a predetermined arrangement, a position where the specific pattern 22B should appear in the bitmap data is predicted (S61), and the bitmap data Among them, a position P serving as a reference for search is determined (S62). It is checked whether or not the dot at the reference position P is black (S63). If the dot is black, the process proceeds to step S66 assuming that the dot constitutes the central portion 41.

  On the other hand, if the dot at the reference position P is not black in S63, the next search position is determined within a certain range from the reference position P (S64), and it is checked again whether the dot at the search position is black. However, when all the areas within a certain range from the reference position P are searched, but no black dot corresponding to the central portion 41 of the specific pattern 22B is found (S65), the search fails (S76). To finish the process.

  In step S66, a black dot connected to the dot at the reference position P in the up / down / left / right and diagonal directions is recursively searched. Then, it is determined whether or not the number of connected black dots is within a certain range (S67). If the number of connected black dots exceeds a certain number, it is determined that the area where the black dots are connected is not closed, or the area of the central portion 41 is too large even if it is closed. When the number of connected black dots is less than a certain number, it is determined that the noise is not the central portion 41 but merely noise. If the number of connected black dots is not within a certain range, the process returns to S64 and the process is repeated.

  On the other hand, if the number of connected black dots is within a certain range (S67), the process proceeds to S68 to check whether the width and height of the connected region of black dots are within a certain range. To check the shape of the area. The width of the connected area is expressed as the maximum value of the X coordinate of the connected area minus the minimum value, and the height of the connected area is expressed as the maximum value of the Y coordinate minus the minimum value. The If the width and height of the area where the black dots are connected are not within a certain range, the process returns to S64 and the process is repeated.

  On the other hand, if the width and height of the area where the black dots are connected are within a certain range (S68), it is determined that the area where the black dots are connected is the central portion 41, and the process proceeds to S69.

  Next, in S69, a check regarding the first annular portion 42 is started. One black dot (the one with the smallest Y coordinate) on the bottom surface of the area where the black dots determined to be the central portion 41 are connected is selected (S69). Then, as shown by an arrow in FIG. 17, a search is performed downward from the region 41, and a black dot (second second) appearing next to a white dot (considered as a white dot constituting the first annular portion 41). A search is made for a black dot constituting the annular portion 42 (S70). If the next black dot is not found within a certain distance after entering the white dot area, it is determined that the white dot area is not the first annular portion 42 of the specific pattern 22B (S71), and the process returns to S64. And redo the process. On the other hand, when the next black dot is found within a certain distance after entering the white dot region (S71), it is considered that the black dot constitutes the second annular portion 43 of the specific pattern 22B. Then, as shown by the arrow in FIG. 17, the left method (following the wall of the maze while putting the left hand on the wall along the inner periphery of the region considered to be the second annular portion 43, that is, the boundary between the black dots and the white dots. By the method) (S72). If it is not possible to make a round within a certain step, it is determined that the white dot area is not closed or is too large even if it is closed (S73). Further, when the left method is performed in the counterclockwise direction, the white dot area is not closed, but it is considered that a certain black dot closed area is searched as shown in FIG. (S74). In these cases, the process returns to S64 and starts again. The specific pattern 22B can be recognized by clearing all the steps S61 to S74 (S75).

  Thus, the specific pattern 22B can be recognized by a simple algorithm.

  FIG. 19 shows an example of a processing flow for recognizing the specific pattern 22A shown in FIG.

  First, when the specific pattern 22A is arranged in the information recording area 23 according to a predetermined arrangement, a position where the specific pattern 22A should appear in the bitmap data is predicted (S41), and the bitmap data A position P to be a reference for search is determined (S42). It is checked whether the dot at the reference position P is white (S43). If the dot is white, the process proceeds to step S46 assuming that the dot constitutes the central closed region 44.

  On the other hand, if the dot at the reference position P is not white in S43, the next search position is determined within a certain range from the reference position P (S44), and it is checked again whether the dot at the search position is white. If all the areas within a certain range from the reference position P are searched, but no white dot corresponding to the central closed region 44 of the specific pattern 22A is found (S45), the search fails (S50). The process ends.

  In step S46, the white dot connected to the white dot at the reference position P in the up / down / left / right and diagonal directions is recursively searched. Then, it is determined whether or not the number of connected white dots is within a certain range (S47). If the number of connected white dots exceeds a certain number, it is determined that the area where the white dots are connected is not closed, or the area as the central closed area 44 is too large even if it is closed. If the number of connected white dots is less than a certain number, it is determined that the noise is not the central closed region 44 but merely noise. If the number of connected white dots is not within a certain range, the process returns to S44 and the process is repeated. Also, it is checked whether the width and height of the region where the white dots are connected are within a certain range, and a check is made regarding the shape of the region. If the width and height of the area where the white dots are connected are not within the predetermined range, the process returns to S44 and the process is repeated (S48). Then, by clearing all the steps S41 to S48, the specific pattern 22A can be recognized (S49).

  Thus, the specific pattern 22A can be recognized by a simple algorithm.

  The processing flow shown in FIGS. 16 and 19 only checks some of the necessary conditions for configuring the specific patterns 22A and 22B, but recognizes the specific patterns 22A and 22B with almost no problem in practical use. Can do. Moreover, it is efficient.

(4) About the shape of the cell By the way, although the shape of the cell which comprises the information recording area 23 was demonstrated as a square until now, the shape of the cell is not restricted to a square.

  As will be described later, in the case of using a reading method in which recorded information is read from a reading device to form bitmap data and the bitmap data is analyzed, one square is 4 × 4 on the bitmap or It is necessary to have a spread of about 3 × 3 dots or more. In such a case, a square having the smallest area for analysis of the bitmap can be realized by making the square shape a square. Square squares are therefore advantageous.

  However, it is a story on bitmap data. For example, a scanner having a line sensor in the main scanning direction of 200 dpi, which realizes the sub-scanning direction of 400 dpi by adjusting the speed of the paper feed motor is used. In this case, it is advantageous to use a rectangular cell having a ratio of 1 to 2 on the recording medium so that it can be read as a square cell on the bitmap.

  Moreover, as the shape of the mesh, for example, a parallelogram that has no sides orthogonal to each other can be adopted. FIG. 20 shows an example in which an information recording area 73 is formed on the recording surface 20 with a parallelogram as a grid, and specific patterns 72 are arranged in the information recording area 73 at regular intervals. As the specific pattern 72, a pattern obtained by deforming the specific pattern 22B of FIG. 7 in one direction into a parallelogram is used. Reference numeral 71 denotes a cell representing original recording information.

(5) Mapping of Record Information A method of mapping record information on the information recording area 23 will be described in relation to the arrangement of the specific pattern 22, taking the digital information record carrier shown in FIG. 1 as an example.

In the digital information record carrier of FIG. 1, the information recording area 23 has virtually 35 horizontal × 50 vertical = 1750 cells. In the information recording area 23, 12 specific patterns 22, 22,... Are arranged every 15th horizontal and every 15th vertical. As already described, the ten specific patterns 22 belonging to the uppermost, lowermost, left, and right columns in the arrangement of the specific patterns 22 are arranged along the outer periphery of the information recording area 23, and the remaining two specific patterns 22 are specified. The pattern 22 is arranged inside (near the center) away from the outer periphery of the information recording area 23. In particular, those present at the four corners in the arrangement of the specific pattern 22 are arranged at the four corners of the information recording area 23. Since each specific pattern 22 is composed of 25 (5 horizontal × 5 vertical) cells, the number of cells used in the specific pattern is 300 out of 1750 cells in the entire information recording area 23. Therefore, the remaining 1450 cells 21 are used to represent original recording information, and can represent 1450 bits of information ( ^{21450 different} types of information).

  FIG. 22 shows a part 23A of a horizontal 35 × vertical 20 cell corresponding to a part (upper part) of the information recording area 23 shown in FIG. In the information recording area 23A, six specific patterns 22 (3 in the horizontal direction × 2 in the vertical direction) are arranged every 15 squares and every 15 vertical lines. Of the 700 cells in the information recording area 23A, the number of cells used in the specific pattern 22 is 150, and the remaining 550 cells 21 are used to represent original recording information. Addresses 1, 2,..., 550 (only some addresses are shown for simplicity) are attached to the cells 21 representing the original recording information. The address addresses are from address 1 to address 10 from the leftmost square of the first row in contact with the specific pattern 22 in the upper left corner to the right, and from address 11 to address 20 beyond the specific pattern 22 in the center of the uppermost row. Yes. The second to fifth rows are similarly numbered, and the grid that touches the specific pattern at the right end of the fifth row is the 100th address. From the sixth line to the fifteenth line, the addresses are increased one by one from the leftmost grid to the right. From the 16th line to the 20th line, as in the case of the 1st line to the 5th line, the numbering is performed beyond the center specific pattern 22. In this way, when the specific pattern 22 is arranged at the center of the row, the addressing is performed beyond the specific pattern 22. The first bit information of the record information corresponds to the cell of address address 1, black when the value of the bit information is “1”, and white when the value of “0”. Thereafter, recording information is similarly recorded, and as a result, 550-bit digital information can be mapped to 550 cells 21 in the information recording area 23A.

  In FIG. 22, the bit information is arranged from left to right as the arrangement of the bit information. However, how the bit information is mapped to the cell 21 can be freely performed without being restricted by this example.

(6) Configuration and Basic Operation of Digital Information Recording Device FIG. 21 shows a schematic configuration of a digital information recording device for carrying out the present invention. This apparatus includes an input device 82 as input means, an information recording device 81 as pattern generation means, and a printing device 83 as printing means. The input device 82 includes, for example, a keyboard, a database, and the like, and can read various data. The information recording device 81 includes an input unit 84, a data conversion unit 85, an output unit 86, and a data conversion (coding) algorithm 87. The input unit 84 receives data from the input device 82 as input information and passes it to the data conversion unit 85. The data conversion unit 85 converts the input information received from the input unit 84 into the expression format (format) of the present invention based on the data conversion (encoding) algorithm 87 and passes it to the output unit 86 as output information.

  The output unit 86 outputs the output information received from the data conversion unit 85 to the printing device 83. In general, the output information passed to the printing device 83 is a bit image. The printing device 83 is configured by, for example, a dot printer, a laser printer, or the like according to the required printing accuracy.

  This information recording apparatus can record various data to be recorded on the recording surface 20 of the record carrier according to the flow shown in FIG.

  (I) First, the input device 82 reads various data (S01), and passes the read data to the input unit 84 of the information recording device 81.

  (Ii) In the information recording device 81, the data conversion unit 85 that has received the data via the input unit 84 performs the following processing based on the data conversion (coding) algorithm 86.

  First, the size of the information recording area 23 is determined according to the size of the data (S02). The size of the information recording area 23 is determined by the number of recording information and the specific pattern 22 to be added. There are cases where restrictions are imposed such as making the width of the information recording area 23 a certain size or making the shape of the information recording area 23 a square. Note that this step is not necessary when the size of the recorded information is predetermined.

  The specific pattern 22 is arranged at a predetermined position in the information recording area 23 (S03). As this arrangement, for example, a grid-like arrangement in which the specific pattern 22 appears every 10th vertical grid and every 15th horizontal grid is employed.

  In the information recording area 23, the bit information of the data is arranged in accordance with a predetermined mapping for the cell 21 representing the original recording information (S04). As this mapping, for example, the mapping already described with reference to FIG. 22 is adopted.

  (Iii) The recording device 83 prints the recording information delivered from the output unit 86 of the information recording device 81 on the recording surface 20 (S05).

  Thus, according to this digital information recording apparatus, digital information can be recorded on the recording surface 20 of the record carrier.

(7) Searching for a specific pattern and reading information using the specific pattern A method for decoding recorded information recorded on a digital information record carrier as shown in FIG. 1 will be described.

  The recording information is read by the reading device, and as shown in FIG. 24, bitmap data composed of monochrome pixels corresponding to the recording information is obtained. In FIG. 24, the same reference numerals are used for elements corresponding to those on the recording surface 20 of FIG. 1 for simplicity, and numbers a00 to a44 are used to distinguish the specific patterns 22 from each other. Decoding is performed on this bitmap data.

  (I) First, a specific pattern is searched.

  First, a rectangular area corresponding to the information recording area 23 is determined from the bitmap data, and its four corners are examined. In this example, since the specific patterns a00, a04, a40, a44 are arranged at the four corners, the specific patterns a00, a04, a40, a44 at the four corners are detected.

  Since it is known in advance that each specific pattern 22 is the specific pattern 22B shown in FIG. 7 and is composed of 5 × 5 squares, the specific patterns a00, a04, a40, a44 at the four corners are analyzed. By doing so, it is possible to know the approximate size of the meshes virtually set in the information recording area 23.

  Subsequently, the specific pattern 22 arranged along the four sides of the information recording area 23 is searched. Taking the search for the specific pattern 22 along the upper side of the information recording area 23 as an example, first, the specific pattern a01 next to the specific pattern a00 in the upper left corner is searched, and then sequentially searched for a02 and a03 toward the right. For example, when searching for the specific pattern a01, since it is known in advance that the specific pattern appears in the information recording area 23 at a horizontal 15th-cell pitch, the specific pattern a01 is at a position advanced by 15th-cell in the direction from a00 to a04. Expected to appear. Therefore, the vicinity of the predicted position is examined to search for a shape (pattern) that matches the specific pattern 22. By repeating this operation, the specific pattern 22 along the upper side of the information recording area 23 can be found sequentially. Similarly, the specific pattern 22 along the other three sides of the information recording area 23 can also be found sequentially.

  The specific patterns a11 to a13, a21 to a23, and a31 to a33 in the vicinity of the central portion that are not adjacent to the four sides of the information recording area 23 utilize the fact that the specific patterns are arranged in a lattice pattern in the information recording area 23. It can be found by predicting the position, examining the vicinity of the predicted position, and searching for a shape that matches the specific pattern.

  Here, the following two methods are conceivable as a method of searching for the specific patterns a11 to a13, a21 to a23, and a31 to a33 near the center.

  As shown in FIG. 25, the first search method obtains an intersection between a straight line connecting the corresponding specific patterns 22 on the left and right and a straight line connecting the corresponding specific patterns 22 on the upper and lower sides. This is a method for searching for a specific pattern 22 in the vicinity. That is, the specific patterns a10, a20, a30 along the left side and the specific patterns a14, a24, a34 along the right side are associated with each other by a straight line, and the specific patterns a01, a02, a03 along the upper side and along the lower side The specific patterns a41, a42, and a43 are associated with each other and connected by straight lines, and intersections b11 to b13, b21 to b23, and b31 to b33 of these straight lines are obtained. It is expected that specific patterns a11 to a13, a21 to a23, and a31 to a33 appear near the intersections b11 to b13, b21 to b23, b31 to b33. Then, the vicinity of the expected position is examined to search for a shape that matches the specific pattern 22. For example, when searching for the specific pattern a12, an intersection b12 between a straight line connecting a10 and a14 and a straight line connecting a02 and a42 is set as an expected position, and the vicinity of the position is examined to find the specific pattern a12.

  As shown in FIG. 26, the second search method is a method for predicting the position of a nearby specific pattern 22 using three known adjacent specific patterns 22. In general, as shown in FIG. 27, if three coordinates c00, c01, and c10 are known, another coordinate c11 that forms a parallelogram with the three coordinates is a vector from the three coordinates c00, c01, and c10. (A combination of the vector c00 → c01 and the vector c00 → c10 is equal to the vector c00 → c11). Therefore, for example, the position of the specific pattern a11 is predicted using the coordinates of the specific patterns a00, a01, and a10, and the vicinity of the predicted position is examined to search for a shape that matches the specific pattern. The search for the specific pattern a12 is performed using the newly obtained coordinates of the specific pattern a11 and the coordinates of the specific patterns a01 and a02. In this way, the specific patterns a11 to a13, a21 to a23, and a31 to a33 in the vicinity of the central portion can be sequentially searched.

  The distortion of the recording surface 20 changes continuously in the recording surface 20 as shown in FIG. Therefore, with respect to the predicted position, the second search method that determines the position of a nearby specific pattern using the position information of the adjacent specific pattern 22 is compared to the first search method that searches for the entire position. The accuracy is considered high. However, in the second search method, once the position of the specific pattern is mistaken, the error is reflected when calculating the predicted position of the next adjacent specific pattern. On the other hand, this is not the case with the first search method. In the end, we cannot say which search method is advantageous.

  (Ii) Next, the position (position information) of the searched specific pattern 22 is obtained.

  FIG. 28 exemplifies bit map data obtained by reading the specific pattern 22B shown in FIG. The position of the specific pattern 22B can be indicated by the position of the center portion 41, and the position of the center portion 41 is preferably represented by the position of the center of gravity.

  The center-of-gravity position of the central portion 41 in the bitmap data of FIG. 28 can be obtained by examining the positions of all the black bits constituting the central portion 41 and averaging them. When the center of gravity position is obtained by averaging, the more center samples are used for averaging, the more accurate center of gravity position is obtained. Since the specific pattern 22B has a symmetric shape with respect to the top, bottom, left, and right, the center of gravity of the first annular portion 42 should also coincide with the center of gravity of the center portion 41. Therefore, in the bitmap data of FIG. 28, by averaging the positions of all black bits constituting the central portion 41 and the positions of all white bits constituting the first annular portion 42, respectively, The position of the center of gravity can be obtained with high accuracy. Further, it is conceivable to use the information of the second annular portion 43. However, when the value of the mesh representing the original recording information adjacent to the outside of the second annular portion 43 is black, the collar of the second annular portion 43 is used. Since it is difficult to distinguish the boundary between the eye and the region 21 representing the original recording information, it is not practical to use the information of the second annular portion 43.

  Also for the specific pattern 22A shown in FIG. 6, the position of the center of gravity can be obtained by averaging the positions of all the white bits constituting the central closed region 44. However, it should be noted that the position of the center of gravity represents the middle position of the four cells constituting the central closed region 44, and is not a point representing one of the cells.

  (Iii) Next, the value of the cell 21 representing the original recording information is obtained.

  This method will be described with reference to FIG. FIG. 29 schematically shows a region including four adjacent specific patterns 22 in the information recording region 23 (a region including a cell having M rows and N columns). Even when the non-uniform distortion as shown in FIG. 3B occurs on the entire recording surface 20, it occurs in a small area surrounded by four adjacent specific patterns. The distortion is approximated by a nearly proportional distortion.

29, the position of the specific pattern 22 in the upper left (0th row, 0th column) is P ₀₀ , the position of the specific pattern 22 in the upper right (0th row, Nth column) is P _0N , and the position in the lower left (Mth row, 0th column) is specified. The position of the pattern 22 is P _M0 , and the position of the specific pattern 22 at the lower right (Mth row and Nth column) is _PMN, and the mth row and the nth column (m, n) in the region surrounded by these four specific patterns 22 Let P _mn be the position of the square of n).

となる。 A point obtained by internally dividing P ₀₀ and P _0N into n: (N−n) is P _0n , and a point obtained by internally dividing P _M0 and P _MN into n: (N−n) is represented by P _Mn , P ₀₀ and P and _M0 m: (M-m) a point obtained by internally dividing the P _m0, P _0N a and P _MN m: When a point obtained by internally dividing the (M-m) and P _mN, the position of the meshes P _mn obtaining Is represented as an intersection of a straight line L1 connecting P _0n and P _Mn and a straight line L2 connecting P _m0 and P _mN . The intersection point P _mn between the straight line L1 and the straight line L2 is also expressed as a point obtained by internally dividing the straight line L1 into m: (M−m) or a point obtained by internally dividing the straight line L2 into n: (N−n). By using the positions P ₀₀ , P _0N , P _M0 , and P _MN of the four specific patterns 22, the cell position P _mn in the area surrounded by the four specific patterns 22 is expressed as follows:

It becomes.

From the point of view of finding the position P _mn of the _square representing the original recording information proportionally from the positions P ₀₀ , P _0N , P _M0 , and P _{MN of the} four specific patterns 22 adjacent to each other, Not only the outer dividing point can be used. Therefore, as shown in FIG. 30, even if any of the four specific patterns 22 surrounding the target cell P _mn is not found (those marked with “x”), for example, Using the set of four specific patterns 22, the position P _mn of the target cell can be obtained by a method using proportional division (outer division).

  Further, it is not always necessary to select the four specific patterns 22 that are adjacent to each other. As shown in FIG. 31, when any one of the four adjacent specific patterns is not found (those marked with x), for example, the four specific patterns that are adjacent to each other vertically and spaced apart from each other to the left and right. Similar proportional division processing is possible using 22 sets.

  Furthermore, the method for obtaining the position of an arbitrary grid from the four specific patterns can be applied not only when the information recording area is rectangular, but also when the information recording area is, for example, a parallelogram (FIG. 20).

In this way, the target cell position P _mn is obtained, and the obtained value of the cell can be obtained.

(8) Configuration and Basic Operation of Digital Information Decoding Device FIG. 32 shows a schematic configuration of a digital information decoding device according to an embodiment of the present invention. This apparatus includes a reading device 92 as reading means, an information decoding device 91 as information decoding means, and an output device 93 as output means. The reading device 92 is configured by, for example, an image scanner, a CCD (charge coupled device) camera, or the like according to the required reading accuracy, and can read the recording information printed on the recording surface 20 such as paper.

  The information decoding device 91 includes an input unit 94, a data conversion unit 95, an output unit 96, and a data conversion (decoding) algorithm 97. The input unit 94 receives data from the reading device 92 as input information and passes it to the data conversion unit 95. In general, input information passed from the reading device 92 to the input unit 94 is a bit image. The data conversion unit 95 decodes the input information received from the input unit 94 based on the data conversion (decoding) algorithm 97 and passes it to the output unit 96 as output information. The output unit 96 outputs the output information received from the data conversion unit 95 to the output device 93. The output device 93 is configured by, for example, a display, a database, etc., and displays or stores the read information.

  Here, the data conversion (coding) algorithm 87 in FIG. 23 and the data conversion (decoding) algorithm 97 in FIG. 32 perform conversions opposite to each other. Therefore, the recording information printed on the recording surface 20 by the recording device of FIG. 23 can be read by the decoding device of FIG. 32, and the same data as the original data can be obtained.

  This information decoding apparatus can read the information recorded on the recording surface 20 of the record carrier according to the flow shown in FIG. Here, as shown in FIG. 1, the recording information in which the specific patterns 22 are arranged in a lattice pattern at regular intervals in the information recording area 23 and the specific patterns 22 are arranged at the four corners of the information recording area 23. Shall be deciphered.

  (I) First, the reading device 92 reads the information recorded on the recording surface 20 of the record carrier (S11) and passes it to the input unit 94 of the information decoding device 91.

  (Ii) In the information decoding device 91, the data conversion unit 95 that has received data via the input unit 94 performs the following processing based on the data conversion (decoding) algorithm 96.

  First, the specific patterns 22 arranged at the four corners in the information recording area 23 are extracted (S12).

  Next, the size of one cell is determined based on the information of the specific patterns 22 at the four corners (S13).

  Next, the remaining specific patterns are extracted based on the predetermined arrangement information (S14). Here, the predetermined arrangement information is information about the arrangement of the specific pattern 22 such as, for example, arranged in a grid so that the specific pattern appears every 10 squares or every 15 squares.

  Next, based on the information (position information) about the position of the extracted specific pattern, the position of the cell 21 representing the original recording information is determined (S15).

  Next, information recorded in such a cell 21 is read according to a predetermined mapping (S16). Here, the predetermined mapping is associating each cell 21 with the bit information as already described with reference to FIG.

  (Iii) Then, the output device 93 outputs the output information passed from the output unit 96 of the information recording device 91 (S17).

  Thus, according to this digital information decoding apparatus, the digital information recorded on the recording surface 20 of the record carrier can be decoded.

(9) Specific patterns at the four corners of the information recording area In the present invention, a plurality of specific patterns 22 are arranged in the information recording area 23, but the specific patterns 22 arranged at the four corners of the information recording area 23 are other specific patterns. More important than patterns.

  (I) In the information decoding method shown in the processing flow of FIG. 33, as shown in S12, the specific patterns 22 at the four corners of the information recording area 23 are searched in advance of other specific patterns. This is because the specific pattern 22 at the four corners is easier to find than other specific patterns, and the range occupied by the information recording area 23 in the recording surface 20 is determined by first finding the specific pattern 22 at the four corners. There is a reason that can be.

  That is, the presence of the specific patterns 22 at the four corners of the information recording area 23 makes it possible to easily recognize (so-called cut out) the area occupied by the information recording area 23 in the recording surface 20 at the time of reading. For example, in the example of FIG. 1, even if the cells constituting the information recording area 23 are all white, the range occupied by the information recording area 23 can be easily determined by the presence of the specific patterns 22 at the four corners. it can. The same applies even if all the cells constituting the information recording area 23 are black. Note that it is not considered that the specific pattern is composed entirely of white cells. On the other hand, when the specific pattern 22 does not exist at the four corners of the information recording area 23, it is impossible to distinguish white in the information recording area 23 from white outside the information recording area 23. This is because there may be a case where all of the cells along the outer periphery of the information recording area 23 are white.

  (Ii) FIG. 34 schematically shows a method of searching for the specific patterns 22 at the four corners of the information recording area 23 from the bitmap data constituting the recording information. When searching for the specific pattern 22 in the upper left corner, scanning is performed in an oblique direction (indicated by an arrow in the drawing) from the upper left corner of the bitmap data. If the outside of the information recording area 23 is composed of white bits, the black bits that first appear in the diagonal scan are the black bits that make up the specific pattern 22 in the upper left corner. Thus, the specific pattern 22 in the upper left corner can be found. Of course, the specific patterns 22 in the upper right corner, lower left corner, and lower right corner of the information recording area 23 can be similarly found by scanning diagonally from the upper right corner, lower left corner, and lower right corner of the bitmap data.

(10) Segments It is often beneficial to divide the information recording area into segments and record information in segment units.

  FIG. 35 shows a segment G set by the digital information recording method according to the embodiment of the present invention. The segment G is configured by arranging a specific pattern 22 (hereinafter, the specific pattern 22B shown in FIG. 7) on the rectangular block 21 so as to overlap each other. Specifically, the rectangular block 21 has a size larger than the size of the specific pattern 22 in the vertical direction and the horizontal direction, and is configured by 25 squares × 25 squares = 625 squares. The specific pattern 22 is divided into two parts in the vertical direction and the horizontal direction, for a total of four parts, and is arranged at positions inscribed in the four corners of the rectangular block 21 as four divided patterns 22a, 22b, 22c, and 22d. The specific pattern 22 occupies the 25th grid (the 9th grid in the upper left corner, the 6th grid in the upper right corner, the 6th grid in the lower left corner, and the 4th grid in the lower right corner). It has become a cicada. In addition, the dotted line and solid line which divide the cells are virtual. For convenience, FIG. 35 shows an aspect in which the specific pattern 22 is synthesized by adding a portion that complements each of the divided patterns 22a, 22b, 22c, and 22d to the outside of the rectangular block 21.

  As shown in FIG. 36, the information recording area 23 is set by arranging a plurality of the segments G on the recording surface 20 without any gaps. In this example, the information recording area 23 is configured by arranging a total of nine segments G, 3 vertical × 3 horizontal. Since each divided pattern is arranged at the four corners of the rectangular block 21, when the segment G is arranged in this way, the four rectangular blocks 21 (segment G) are adjacent to each other on the boundary points adjacent to each other with their vertices facing each other. The specific pattern 22 is synthesized by the divided patterns arranged in 21. In addition, the segment G existing along the outer periphery of the recording information recording area 23 is added by circumscribing a portion that complements each of the divided patterns 22a, 22b, 22c, and 22d so as to synthesize the specific pattern 22 on the outer peripheral side. is doing.

  As described above, when the specific patterns 22 are arranged at the four corners of the segment G, the specific patterns 22 are arranged at the four corners of the information recording area 23. Therefore, it is advantageous in terms of ease of recognizing the range of the information recording area 23 at the time of reading. It becomes. However, the specific pattern 22 does not necessarily exist at the four corners of the information recording area 23. As shown in FIG. 37, the specific pattern 22 may be arranged at the center of each segment G. Thus, if the arrangement of the segments G and the arrangement of the specific patterns 22 are synchronized, information recording can be performed in segment G units.

  The advantages of segmentation are as follows.

  (I) Since processing can be performed in units of segment G, efficient reading processing is possible. Further, when the memory buffer capacity of the reading device is small, it can be dealt with by sequentially repeating (reading → decoding processing). That is, the memory buffer can be saved.

  (Ii) Processing such as reading error detection / error correction can be performed in segment G units. In this case, surplus bits such as a checksum and CRC are added for each segment G. In addition, shuffling processing for dispersing burst errors can be performed for each segment G.

  (Iii) When a reading error occurs, only the target segment G can be read again. Also, in re-reading, the processing in the reading device, such as increasing the magnification of the CCD camera, and the processing at the time of analysis, such as using a more accurate analysis method for the read image, are different from the first method. Can be re-read using. At this time, if reading that is expected to be performed at high speed is used for the first reading and time is required for re-reading, but reading with higher accuracy is used, high-speed and reliable reading can be performed as a whole.

  (Iv) The shape of the information recording area 23 can be set freely. That is, as long as the segments G are arranged without gaps, it is possible to freely set how many segments G are arranged vertically and horizontally. Not only can it be arranged in a rectangular shape such as a vertically long shape or a horizontally long shape, but also a shape in which the corners of the rectangle are missing as shown in FIG. 38, or an extremely complicated arrangement as shown in FIG.

  Here, in particular, when a complicated arrangement as shown in FIG. 39 is adopted, adjacent information indicating whether or not there is a segment G adjacent to each segment G in the vertical and horizontal directions, and information assigned to each segment G Recording number information indicating the order of unit information is convenient for reading. For example, FIG. 40 shows a state where “arrangement” as adjacent information and “number” as number information are recorded in each segment G arranged as shown in FIG. The item “arrangement” indicates whether or not there is a segment G adjacent to “right / bottom / left / bottom” of a certain segment G as 4-bit information. The four bits correspond to “right / lower / left / upper” in order from the upper bit, and the value 1 of each bit represents “present” and the value 0 represents “not present”. The item “number” indicates in what order the unit information assigned to the eight segments G in the information recording area 23 is arranged in the original digital information. In this case, at the time of reading, the same order as the order in which the unit information was recorded in the recording stage while checking whether there is a segment G adjacent to one segment G based on the “arrangement” and “number”. The unit information can be read from each segment G.

  FIG. 41 shows how digital information to be recorded is recorded in the information recording area 23 in segment units.

  In this example, it is assumed that the information recording area 23 is composed of 2 vertical × 3 horizontal segments G1,..., G6.

  First, the digital information D to be recorded is divided into fixed lengths according to the number of segments G, and unit data 112 (D1,..., D6) as unit information is created. Additional information data 113 is added to each unit data 112 as necessary. As the additional information data, error detection or error correction data such as a checksum or CRC, data representing the “arrangement” or “number” of the segment G, and the like can be considered.

  Next, the unit data 112 added with the additional information data 113 (also referred to as “unit data”) 111 is assigned in correspondence with each segment G (mapping), and the specific pattern 22 in the segment G is assigned. Record in a grid other than the grid occupied by.

  In this example, the first unit data 111 including D1 is assigned to the segment G1 in the upper left corner. Similarly, the second,..., Sixth unit data including D2,..., D6 are allocated to the segments G2,. In each segment G, as shown in FIG. 43, the unit data 111 is allocated and recorded in the cells other than the cells occupied by the specific pattern 22 in the rectangular block 21. In this example, mapping is performed from left to right in the first row and from left to right in the second row.

  When reading the information recorded in the information recording area 23, it can be read in segment units by the reverse process of recording.

(11) Layout of segment G When the segment G is arranged on the recording surface 22 to form the information recording area 23, it is desirable to arrange according to a predetermined arrangement rule including the direction and number of the segments G to be arranged.

  Here, the arrangement rule does not instruct how to arrange each segment G, but instructs a superordinate concept including the direction and number in which the segments G should be arranged.

  For example, when 16 segments G1,..., G16 are arranged, an example of layout in a square as shown in FIG. 44 (a), a rectangular shape with two horizontal segments as shown in FIG. As an example of layout, there can be considered an example in which the number of segments in the vertical direction is set to two and the layout is made into a vertically long rectangle as shown in FIG. In any of the examples of FIGS. 44 (a), (b), and (c), the segments G are first arranged from right to left, and those arranged from right to left are arranged from top to bottom. If such an arrangement rule does not change even if the layout changes, the unit information can be obtained at the recording stage based on the arrangement rule at the time of reading even if the “number” information as described above is not included in the segment G. Unit information can be read from each segment G in the same order as recorded. Therefore, the original digital information can be easily restored.

(12) Decoding Device for Performing Reading in Segment Unit FIG. 45 shows a schematic configuration of a digital information decoding device of one embodiment. This information decoding apparatus includes a reading apparatus control apparatus 98 that constitutes a part of the control means in addition to the components of the information decoding apparatus shown in FIG. This reading device control device 98 changes the relative position between the reading device 92 and the recording surface 20 in order to obtain appropriate image information from the recording surface 20 based on the information obtained by the data conversion unit 95.

  This information decoding apparatus can read the information recorded in the information recording area 23 on the recording surface in segment units according to the flow shown in FIG.

  In this example, as shown in FIG. 42, a case will be described in which the information recording area 23 is composed of an array of segments G 3 × 2 horizontally.

  (I) First, the reading portion is set to the upper left portion of the recording surface 20 (S21), and the recording surface 20 is read to generate image information (S22). This processing is performed by the reading device control device 98 controlling the operation of the reading device 92 in accordance with an instruction from the data conversion unit 95. Subsequently, it is checked whether or not there is a specific pattern 22 arranged in the upper left corner of the information recording area 23 in this image information (S23). If there is no upper left corner specific pattern 22 in the read image information, the reading portion is sequentially changed, and the search is continued until the upper left corner specific pattern 22 is found (S24). For example, the reading portion may be changed according to the movement of the scan line shown in FIG.

  (Ii) Next, the size of one cell is determined based on the information of the specific pattern 22 found in the upper left corner (S25). If the size of one cell is known, it corresponds to the apex of the segment G existing at the upper left corner of the information recording area 23 in accordance with predetermined arrangement information such as the specific pattern 22 appearing at intervals of 20 cells vertically and 20 cells horizontally. Four specific patterns 22 arranged at the positions to be found are found (S26). That is, with respect to the known specific pattern 22, the “specific pattern 22 on the right side”, the “specific pattern 22 on the lower side”, and the “specific pattern 22 located on the right side of the specific pattern 22 on the lower side” Extract. Thereby, the segment G in the upper left corner can be specified. Then, image information in a range that includes the four specific patterns 22 is generated (S27). This processing is performed by the reading device control device 98 controlling the operation of the reading device 92 in accordance with an instruction from the data conversion unit 95.

  (Iii) Next, in the segment G in the upper left corner defined by the four specific patterns 22, the pattern represented by the cells other than the cells occupied by the specific pattern 22 is decoded and assigned to this segment G Read unit information.

  Specifically, the position of each cell in the segment G is determined based on the position information of the four specific patterns 22 (S28). Subsequently, the information recorded in each cell is read according to a predetermined mapping as shown in FIG. 43 (S29). Then, the read information for one segment G is output (S30).

  (Iv) Next, the specific pattern 22 which becomes the upper left corner in the segment G adjacent to the segment G at the upper left corner is set (S32). In this example, the specific pattern 22 at the upper right corner of the segment G at the upper left corner is set as the specific pattern 22 at the upper left corner of the segment G adjacent to the right. Then, the four specific patterns 22 arranged at the positions corresponding to the vertices of the adjacent segment G are detected (S26), and as shown in FIG. 47, the four specific patterns 22 set the image information capturing range I1. It is changed to I2 so that it is included (S27). Thereafter, the segment G is read in the same manner as the segment G at the upper left corner (S28, S29), and the read information is output (S30). This information is linked to the information that has already been read.

  (V) In this way, as shown in FIG. 47, the image information capturing range is changed to a range including four specific patterns 22 that are sequentially adjacent, such as I1 to I2, and further I3. The first row is read from each segment G from left to right. When the first row is completed, each segment is read from left to right again for the second row. Then, the reading process is terminated when the reading of all the segments G constituting the information recording area 23 is completed (S30).

  In this case, since reading is performed in units of segment G, the reading accuracy can be improved as compared with the case where the entire information recording area 23 is read and decoded. Further, there is an advantage that the memory capacity necessary for storing image information at the time of decoding is only one segment G. This is because when the decoding for one segment G is completed, the result is output, and the image information for the next segment G may be stored (overwritten) in the image memory. In other words, even if the image memory capacity is constant, digital information recorded in the information recording area 23 having a large area can be read.

  Note that the method of changing the image information capture range is not limited to that shown in FIG. For example, as shown in FIG. 48, first, the image information I1 of the segment G for the first row is fetched at a time, then the image information I2 for the second row, and the image information I3 for the third row. The image information may be taken in. This is a technique that can be implemented when a line scanner is used as the reading device 92 (image sensor). When a line scanner is used, decoding can be performed in units of rows in which the segments G are arranged, no matter how long the information recording area 23 is vertically or horizontally. However, since the capturing ranges of the image information partially overlap, when decoding in units of rows in which the segments G are arranged, the image information of the overlapping portion in the information decoding device 91 is remembered, or the reading device It is necessary to rewind the information recording area 23 using the control device 98. This is for adjusting a portion where one image information overlaps with the next image information.

  Further, when the recording surface and the reading means are moved relative to each other in order to change the image information capturing range, it is not always necessary to perform a physical movement using a motor or the like, but by changing the angle of the mirror. Optical items such as changing the capture range of image information and software items such as decoding while storing only the necessary range of image information in the memory are also included in the category of relative movement.

  Actually, the accuracy of the image information necessary for finding the upper left corner of the information recording area 23 is not required to be as precise as the accuracy of the image information necessary for reading the information of each cell in the segment G. For example, it is possible to find the upper left corner of the information recording area 23 even if the first square is coarse image information corresponding to one dot. Rather, if such rough image information is set, there is an advantage that the entire information recording area 23 can be grasped and the upper left corner of the information recording area 23 can be easily found.

  Therefore, as shown in FIG. 50, in addition to the image sensor 133, a zoom-up device 132 that can change the magnification for converting the two-dimensional pattern recorded on the recording surface 20 into image information as an optical system in addition to the image sensor 133. It is desirable to prepare. In this case, as shown in FIG. 49, the accuracy of the image information when finding the upper left corner of the information recording area 23 and the accuracy of the image information when reading the information of each cell in the information recording area 23 are changed. can do. That is, when the upper left corner of the information recording area 23 is found, a range I including the entire information recording area 23 is obtained as shown in FIG. Thereby, the entire information recording area 23 can be grasped and the upper left corner of the information recording area 23 can be easily found. On the other hand, when the four specific patterns 22 arranged at the vertices of the segment G are found and the information of each cell in the information recording area 23 is read, the upper left corner of the information recording area 23 is enlarged as shown in FIG. The obtained range I # is obtained. Thereby, information on the size of the cells can be obtained from the specific pattern 22, the segment G can be determined, and information on each cell in the segment G can be read out.

  Note that the magnification of the zoom-up device 132 may be set separately in the process of finding the four specific patterns 22 arranged at the vertices of the segment G. This is because when searching for a specific pattern using the technique shown in FIG. 17, the characteristics of the specific pattern are simply verified, so that the value of each square mark is evaluated. This is because it is possible to detect a specific pattern without accuracy of image information. Thereby, the four specific patterns 22 arranged at the vertices of the segment G can be easily found.

  In addition, it is a common practice to examine the captured image information with varying accuracy in terms of software. For example, performing the search by setting every other scan line shown in FIG. 34 corresponds to lowering the accuracy of the image information when finding the four corners of the information recording area 23 in terms of software. By reducing the number of scan lines in this way, the processing time for finding the four corners can be shortened.

(13) About margins generated when segments are combined As shown in FIG. 42, when the specific pattern 22 protrudes from each side of the information recording area 23, the information recording area extends along the four sides of the information recording area 23. A bay-like region (shown by hatching, hereinafter referred to as a “margin”) 27 surrounded by the sides 23 and the opposite sides of the protruding specific pattern 22 is generated. The problem is how to use the margin 27.

  Here, it should be noted that the margin 27 is also generated when the information recording area 23 is configured in the following manner.

  For example, as shown in FIG. 51, a segment G is set by placing the specific pattern 22 in the lower right corner of the rectangular block 21 without being divided, so that the segment G is set as shown in FIG. The information recording area 23 is configured in a rectangular shape. Then, the specific pattern 22 is circumscribed and added along the upper and left sides of the information recording area 23 so that the specific patterns 22 are arranged at the four corners of each segment G existing along the upper and left sides of the information recording area 23. To do. This is for the convenience of reading. Note that the added specific pattern 22 is also shown in the segment G of FIG. In this case, a margin part 27 is generated along the upper side and the left side of the information recording area 23.

  Further, as shown in FIG. 53, the segment G is set by dividing the specific pattern 22 into two and arranging the divided patterns 22e and 22f at the lower left corner and the lower right corner of the rectangular block 21, respectively. The information recording area 23 is configured by arranging the segments G in a rectangular shape. Then, the specific pattern 22 is circumscribed and added along the upper side of the information recording area 23 so that the specific pattern 22 is arranged at the four corners of each segment G existing along the upper side of the information recording area 23. As a result, the specific pattern 22 is arranged at a position in contact with the vertex of each segment G. In this case, a margin 27 is generated along the upper side, left side, and right side of the information recording area 23.

  Now, by using a method for calculating the outer dividing point based on the position of the specific pattern 22 or the like, it is possible to put data to be recorded in the information recording area 23 into the area of the margin portion 27 (described above). However, since most of the data is recorded in the segment G, special processing is required when entering data in the margin portion 27.

  Conversely, if no data is entered in the margin portion 27, the margin portion 27 can be used for other purposes. Next, how the margin part 27 can be used will be described.

  (I) Leave as a quiet area.

  A quiet area is an area composed only of white eyes (in some cases, black eyes).

  The merit of setting a quiet area in the margin part 27 is that, when searching for a specific pattern (hereinafter referred to as “peripheral specific pattern”) 22 arranged along the side of the information recording area 23, the peripheral specific pattern is used. The point is that it can be easily found.

  Although the risk of the same or similar pattern appearing in the vicinity of the specific pattern 22 has already been described with reference to FIG. 11, the margin 27 of the aspect shown in FIG. 42 (generated on the four sides of the information recording area 23). In addition, when data is entered as shown in FIG. 54, the same or similar pattern 22 # may appear in the vicinity of the outer periphery specific pattern 22 as seen in the vicinity of the upper center of the information recording area 23. For this reason, at the time of reading, this pattern 22 # may be erroneously recognized as the original outer peripheral specific pattern 22. As described above, since the search for the outer peripheral specific pattern 22 is performed prior to the search for the specific pattern 22 arranged in the information recording area 23, the influence of such erroneous recognition is great.

  On the other hand, if the quiet area 28 is set as shown in FIG. 55 in the margin 27 of the mode shown in FIG. 42 (generated on the four sides of the information recording area 23), each side of the information recording area 23 will be described. Thus, the outer peripheral specific pattern 22 can be easily found. That is, as shown in FIG. 56, even if the same pattern 22 # appears closest to the outer periphery specific pattern 22 along the side of the information recording area 23, the position overlapped diagonally downward by the third square. The pattern 22 # is less likely to be erroneously recognized as the outer peripheral specific pattern 22. Therefore, the search for the outer periphery specific pattern 22 can be easily performed.

  In addition, when the quiet area 28 is set as shown in FIG. 58 in the margin part 27 of the mode shown in FIG. 52 (those occurring intensively on the upper side and the left side of the information recording area 23), With respect to the upper side and the left side, the outer periphery specifying pattern 22 can be found more easily than in the case of FIG. The reason for this is that, as shown in FIG. 57, even if the same pattern 22 # appears closest to the outer periphery specific pattern 22 along the side of the information recording area 23, the grid does not overlap diagonally downward. Because it can only appear in As shown in FIG. 11, the same pattern as the outer periphery specifying pattern 22 is not aligned in the side direction, but a pattern 22 # that is the same as or similar to the outer periphery specifying pattern 22 may appear at the position shown in FIG. Absent. Therefore, as far as the upper side and the left side of the information recording area 23 are concerned, it is possible to search for the outer periphery specifying pattern 22 more easily than when the quiet areas 28 are provided on the four sides of the information recording area 23 (FIG. 55). However, in the lower side and the right side of the information recording area 23, a problem of erroneous recognition may occur as in the case where data is entered in the margin (FIG. 54).

  As shown in FIG. 55, the quiet area 28 is set equally on the upper, lower, left and right sides of the information recording area 23, and the upper and left sides (or the lower and right sides) of the information recording area 23 as shown in FIG. Whether the method of setting the quiet region 28 by focusing only on) is advantageous should be evaluated in the entire search method, and it cannot be said that superiority is inferior.

  (Ii) Insert clocking information.

  The clocking information is set as a clocking pattern in which black and white are alternately added in the direction along the side of the information recording area 23.

  For example, as shown in FIG. 59, it is assumed that the margin portion 27 is composed of 27 horizontal rows × 5 vertical grids, and its lower side is in contact with the information recording area. As shown in FIG. 60A, a clocking pattern is set in the blank space 27 by alternately arranging black and white eyes in the center row.

  The method for predicting the appearance of the next outer peripheral specific pattern 22 at a position advanced by a certain square based on the known outer peripheral specific pattern 22 has already been described as a search method for the outer peripheral specific pattern 22. When this search method is adopted, by searching for the clocking information in the margin part 27, the search for the outer periphery specific pattern 22 can be performed more easily. That is, even if it is erroneous to predict the appearance position of the next specific pattern 22 based on the known specific pattern 22, if the next outer peripheral specific pattern 22 is searched while correcting the error by following the clocking pattern. The next outer periphery specific pattern 22 can be found accurately.

  In addition, when the information recording area 23 includes a large amount of data, when reading information near the center of the information recording area 23, the specific pattern 22 is used rather than reading using the clocking information around the information recording area 23. Although it has already been described that reading is more resistant to distortion, it is more advantageous to use clocking information for reading the vicinity of the periphery of the information recording area 23. Therefore, by using the specific pattern 22 and the clocking information in combination, it is possible to perform reading with higher accuracy.

  As shown in FIG. 60B, the position of the clocking pattern may be a position along the edge of the margin portion 27 instead of the center row of the margin portion 27. Further, the size and shape of the clocking pattern is not limited to the method using the first cell as a unit, and a method using a plurality of cells as a unit is also conceivable. For example, as shown in FIG. 60 (c), the clocking pattern may be constituted by a bar formed by connecting a plurality of cells in a direction perpendicular to the side of the information recording area 23.

  (Iii) Insert frame information.

  As shown in FIG. 62, the frame information is set as a frame pattern 29A extending along a circumscribing line (not shown) with respect to the outer periphery specific pattern 22 protruding from the side of the information recording area 23. In this example, the frame pattern 29 </ b> A is a rod-like shape in which black squares are connected, and the frame pattern 29 </ b> A is arranged with a gap corresponding to the first square with respect to the opposite sides of the outer periphery specifying pattern 22.

  In this case, the range of the information recording area 23 on the recording surface can be easily detected at the time of reading. In addition, since the frame pattern 23 is arranged with a gap corresponding to the first grid with respect to the opposite sides of the outer periphery specifying pattern 22, the search for the outer periphery specifying pattern 22 is not hindered. That is, when a search is performed along the side of the information recording area 23, each time black and white are switched, the outer circumference specifying pattern 22, the first gap, the frame pattern 29A, the first gap, the outer circumference It can be considered that the specific patterns 22 appear in order, and the outer peripheral specific pattern 22 can be easily found. On the other hand, if the frame pattern 29 is connected to the outer periphery specific pattern 22 as shown in FIG.

  The clocking pattern shown in FIG. 60 (b) is effective as a frame pattern because it is along (is in contact with) the outer tangent of the outer periphery specifying pattern 22.

  (Iv) Enter information indicating whether the pattern is a corner specific pattern or a corner segment.

  When searching for the specific patterns 22 arranged at the four corners of the information recording area 23, another outer peripheral specific pattern 22 is erroneously recognized as the corner specific pattern 22 as shown in FIG. As shown in b), a similar pattern 22 # is misrecognized as the corner specific pattern 22, and furthermore, as shown in FIG. 63C, the stain 22X outside the information recording area 23 is identified as the corner specific pattern. May be misrecognized as 22. In order to prevent such misrecognition, it is effective to record information for distinguishing the four corner specific patterns 22 from the other outer peripheral specific patterns 22 or information for distinguishing the four corner segments from other segments in the margin. It is a countermeasure.

  For example, by modifying the embodiment of FIG. 62, as shown in FIG. 64, means for changing the presence / absence of the pattern 29A in the margin part 27 between the segment G at the four corners and the other segment G can be considered. Thereby, it is possible to easily know whether or not the corner segment G or the corner specific pattern 22 is obtained at the time of reading. That is, in the search for the outer peripheral specific pattern 22, the method for finding the outer peripheral specific pattern 22 between the four corner specific patterns 22 after first finding the four corner specific patterns 22 has already been described. One of them is first found, and a method of reaching the specific pattern 22 at another corner while sequentially searching the peripheral specific pattern 22 is conceivable. In such a case, it is possible to easily know that the four corner specific patterns 22 have been reached by distinguishing the four corner segments from the other segments. For simplicity, the original data recorded in the information recording area 23 is omitted in FIG.

  Similarly, when changing the image information capturing range as shown in FIGS. 47 and 48, the capturing range has reached the four corner segments (FIG. 47) and the bottom row (FIG. 48). Can be easily known.

  Of course, the method may not be a method using the frame pattern 29A as shown in FIG. As long as the pattern of the margin part 27 can be clearly distinguished between the segment G at the four corners and the other segments G, any information can be set for the margin part 27.

  (V) Insert index information.

  Index information refers to information such as the number of segments (vertical x horizontal or total), the size of digital data recorded in the information recording area, the data modulation method, checksum, error correction method, and application type in which data can be used. This information is useful if you know the data recorded in the recording area before actually reading it out. It is advantageous to record these pieces of information in the margin portion 27.

  As for the recording method of the index information, it can be recorded by a recording method in which the first cell is assigned to 1 bit, as with other recording information in the segment, or can be recorded by using a completely different recording method.

  FIG. 65 shows an example in which index information is recorded in the margin portion 27 using a so-called bar code technology. ITF (interleaved 2 of 5) is used as an encoding method. ITF expresses one number (decimal number) with two thick bars (or spaces) and three thin bars (or spaces), and the first digit is composed of bars only. A two-digit number is represented by five bars and five spaces by configuring the numbers with spaces that mesh with the aforementioned bars.

  Let us consider a case where the size of one blank portion 27 is 27th × 5th and a two-digit decimal number “38” is coded. FIG. 66 shows a module configuration for coding decimal numbers 0,..., 9 where 1 corresponds to a thick bar and 0 corresponds to a thin bar. Using this table, “38” can be expressed by a black bar lined with “thick, thin, thin” and a space lined with “thick, thin, thin” that meshes with this black bar. If the narrow bar is the 1st grid width and the thick bar is the 3rd grid width, 1 symbol can be represented by the 18th grid width, and the 4th grid start symbol and the 5th grid stop symbol are added to add 2 digits. (Decimal number) can be represented by a 27th cell width. The height of the bar is the fifth grid width which is the height of the margin 27.

FIG. 67 shows an example in which the barcode recording data of FIG. In the case where the periphery of the specific pattern 22 is composed of black squares as in this example, it is easier to distinguish the specific pattern 22 and the bar code recording data by inverting the bar code recording data in black and white. Note that the start symbol and stop symbol are information necessary for limiting the recording area in the actual barcode, but in this example, the margin 27 is sandwiched between the specific patterns 22 to limit the recording area. The start symbol and the stop symbol can be omitted. In this way, a bar code as a one-dimensional code and a two-dimensional pattern in which a mark is added to each cell on the same recording surface. Can be recorded. Since both are in units of cells, the same printing control method can be applied during printing. Further, at the time of reading, both pieces of information can be decoded using the same decoding device. If the barcode part can be extracted from the captured image information, the barcode part can be decoded by one-dimensional scanning. Moreover, since the bar and space which comprise the said barcode are comprised using a some square, redundancy is large compared with the pattern in which one square represents one value. Therefore, it is possible to form a portion (barcode portion) in which a reading error hardly occurs in the recording surface. Of course, barcode technology other than ITF can be adopted.

  As a method of expressing the index information using another recording method other than the barcode, some information is represented by the number of bars and the thickness of the position as shown in FIG. 68 (a), or FIG. 68 (b). As shown, a method of expressing some information by arranging a plurality of connected black grids is conceivable.

  The advantage of recording the index information by a recording method different from other recording information in the segment G by barcode or other methods is that only the index information can be read even when the internal data cannot be read. . For example, there may be a case where information cannot be read at the grid unit level in the segment G but can be read at the bar unit level of the index information.

  In the example given for the use of the margin part 27, only the method of using the cell as a unit has been described. However, as shown in FIG. 69, a description without the unit of the cell is also possible. However, when the description is made in units of cells, there is an advantage that reading can be performed using the same method as the method for reading the recorded information in the segment.

  Since the index information is important information, it is also an important technique to repeatedly record in a plurality of places so that it is okay if one place is crushed.

  (Vi) Put top / bottom front / back identification marks or readable characters.

  When inserting a record carrier into a scanner using a line sensor, the reader can recognize the direction of the image captured with a CCD camera or other identification mark that allows the human to recognize the direction of the record carrier. The top and bottom left and right identification marks can be incorporated in the margin 27.

  As shown in FIG. 58, when the quiet area 28 is set by concentrating the margins on the upper side and the left side of the information recording area 23, it is easy for humans and machines to identify the upper, lower, left and right sides.

  FIGS. 70A and 70B show an example in which a human being recognizes the upward direction by recording an arrow-shaped pattern in the margin portion 27. FIG. FIG. 71 (a) shows an example in which human beings recognize the left and right sides of the top and bottom by providing a pattern representing characters in the margin part 27 in units of squares. By using characters or symbols, it is possible for humans to understand the contents (for example, part of the index information) as they are. The example of FIG. 71 (b) shows that it can be decoded by a reader incorporated in a word processor named “SHOIN”.

  Each of the above examples employs a method of writing information in the margin portion 27 in units of cells, so that the information content can be read using the same method as the method of reading the recorded information in the segment. Information such as characters that can be understood by humans can be recognized by a machine by using a method such as pattern matching.

  As shown in FIG. 72, top / bottom left / right front / back identification marks, readable characters, or the like may be entered without using a square as a unit. In this case, it is impossible for the reader to decipher, but more information can be recorded than if it is recorded in units of cells. On the other hand, in order to maintain confidentiality, it is also possible to record marks that cannot be read by humans but that can identify the top, bottom, left and right sides of the reading device.

(14) Use of Segment Present at Specific Position Similarly, information for identifying the top, bottom, left and right sides can be recorded in the segment G present at the specific position in the information recording area 23. For example, using the segment G in the upper left corner as a dummy segment, a specific pattern is put in as shown in FIG. 73 (a), an arrow indicating the upward direction is put in as shown in FIG. It is possible to put readable characters as shown in c). In this case, dummy segment data is ignored during reading. However, as shown in FIG. 74, it is possible to use such that valid data is contained in the lower half of the dummy segment, for example. Of course, a plurality of segments G may be used as such dummy segments. In addition, in order to arrange the segments G in the vertical and horizontal arrangements, if data is insufficient, a segment for padding may be used. However, the padding segment may be used as a dummy segment.

  Further, the index information as described above can be recorded in the segment G existing at a specific position in the information recording area 23.

  In this case, the same encoding method and the same reading algorithm can be used for index information and general data. In the reading algorithm, when the specific patterns 22 at the four corners are first examined, it is advantageous to record the index information in the segments G arranged at the four corners. The reason is that if the four corner specific patterns 22 are found, the four corner specific patterns 22 and the remaining three segments of each segment to which they belong can be searched without searching all the other specific patterns 22 arranged in the entire information recording area 23. The specific pattern 22 can be easily found. Therefore, the four corner segments G can be easily determined, and the information of the four corner segments G can be read prior to the information contained in the other segments. For example, as shown in FIG. 75, it is desirable to record the index information in the segment G existing at the upper left corner of the information recording area 23.

  Further, since index information is important, the same index information may be recorded in a plurality of segments G in order to increase redundancy. For example, as shown in FIG. 76, when the same index information is recorded in the segments G existing at the four corners of the information recording area 23, it is assumed that the index information of one segment G out of the four corner segments G is missed. Also, correct index information can be obtained from the index information of the other three segments. Furthermore, the number of segments including index information may be increased or decreased according to the size of the information recording area 23. For example, as shown in FIG. 77, when the size of the information recording area 23 is not so large, the index information is not recorded in all the segments G existing at the four corners, but the segments existing at the upper left corner and the lower right corner. Index information may be recorded only in G. In this case, at the time of reading, the upper right corner and the lower left corner segment G of the four corner segments G are also considered to include the index information, and the reading is performed in the same manner as the upper left corner and the lower right corner segment G. Then, only the contents of the segment G at the upper left corner and the lower right corner that included information that can be decoded as index information among the segments G at the four corners are regarded as index information, and the contents of the segments at the upper right corner and the lower left corner are regarded as data.

  In each of the above examples, the index information is stored in a single segment G. However, a method of increasing the amount of index information by putting different index information in a plurality of segments G is also conceivable. For example, different index information may be recorded in each of the four corner segments G shown in FIG. Further, as shown in FIG. 78 (a), index information may be recorded across the segment G1 in the upper left corner and the three segments G2, G3, G4 adjacent to the right, or FIG. 78 (b). As shown in FIG. 6, the index information may be recorded across the segment G1 in the upper left corner G1 and the three segments G2, G6, G7 adjacent thereto.

(15) Example of recording index information at four corners of general information recording area The method for recording index information at the four corners of the information recording area set in the recording surface is to use the segment G to record the information recording area. The present invention is not limited to the configuration, and can be widely applied to rectangular information recording areas. For example, as described in Japanese Patent Application No. Hei 6-70911 by the applicant of the present invention, a small block composed of a plurality of connected cells is set, and a plurality of the small blocks are arranged on the recording surface without any gaps to record information. The present invention can also be applied when a region is configured.

  In this recording method, for example, as shown in FIG. 80, a small block W in which a total of 16 squares, 4 in the horizontal direction and 4 in the horizontal direction, are connected to the square is set, and as shown in FIG. A rectangular information recording area 23 is formed by arranging the blocks W in a matrix in the horizontal and vertical directions on the recording surface 20 (note that the boundary lines between the small blocks W in FIG. 79 are virtual). . Here, among the patterns that can be taken by the small block W by giving white and black marks (values) to each cell, the number of consecutive same values in both the vertical and horizontal directions is 3 or less. Only the pattern which is is adopted as the designated pattern. At this time, the number of designated patterns that the small block W can take is 22,874, and one small block can be associated with a value of 14 bits (16,384). Then, the digital information to be recorded is divided according to the number of small blocks W to create unit information, and this unit information is assigned to each small block W and recorded. By adopting such a designated pattern, the number of cells having the same value in the entire information recording area 23 is always 6 or less in both the vertical direction and the horizontal direction, thereby preventing a reading error from occurring. ing.

  In the example shown in FIG. 79, a control pattern having a checkered pattern is formed in a small block in the upper left corner for the purpose of uniquely determining the top and bottom of the recording surface 20 and for obtaining clocking information for identifying the size of the cell. W1 (see FIG. 81) is assigned. It is assumed that the control pattern W1 and the pattern (see FIG. 82) that can be generated when the control pattern W1 is rotated are not adopted as the designated pattern. Since this control pattern W1 is a pattern in which white and black cells are alternately arranged, the size of the cells can be identified by finding the control pattern W1 in the recording surface 20. Further, by finding this control pattern W1, the top and bottom of the recording surface 20 can be uniquely identified.

  When reading information recorded by such an information recording method, as shown in FIG. 83, the recorded information recorded on the recording surface 20 is read and converted into image information (S11), and the four corners of the information recording area 23 are read. The control pattern W1 is found by identifying the pattern (S12, S13). The control pattern W1 obtains the left and right and clocking information (S14, S15), and based on this, the small block W is cut out from the information recording area 23 (S16), and the information (designated pattern) recorded for each small block is obtained. By converting the original data (S17), the recorded information is decoded (S18, S19). If the control pattern W1 cannot be found in step S13, it is processed as a reading error (S20). In this way, efficient reading can be performed by finding the control pattern W1 arranged in the small blocks at the four corners.

  Further, as in the case of the information recording method using segments as described above, index information can be recorded in a small block existing at a specific position in the information recording area 23. Here, the index information includes the number of small blocks (vertical × horizontal or total number), data size, data modulation method, checksum, error correction method, application type in which data can be used, and the like.

  For example, index information is recorded in the small block W existing in the upper right corner in the example of FIG. In this case, at the time of reading, after finding the control pattern W1 from the recording surface 20, the small block W in the upper right corner is cut out, and the specified pattern indicated by the small block W is examined to obtain the index information. it can. Since the small blocks W are cut out in order from the end, the small blocks W at the four corners can be cut out prior to cutting out other small blocks, and information can be read out in advance. In this example, the index information that can be recorded in one small block is limited to 14 bits or less.

  In order to increase the redundancy of the index information, the same index information can be repeatedly recorded in a plurality of small blocks, or the index information exceeding 14 bits can be recorded across the plurality of small blocks.

  Further, when the information recording area is configured by arranging the small blocks W, as in the case of the information recording method using the segments as described above, the small blocks W are arranged according to a predetermined arrangement rule including the direction and number of the small blocks W to be arranged. can do. Thus, at the time of reading, the original digital information can be easily restored based on this arrangement rule.

It is a figure which shows the aspect of the digital information record carrier of the field | area using this invention. It is a figure which shows typically the digital information record carrier of FIG. It is a figure which shows the state which distortion generate | occur | produced on the recording surface of the said digital information record carrier compared with the state which distortion generate | occur | produced on the recording surface of the conventional digital information record carrier. It is a figure which shows the example which has arrange | positioned the specific pattern in the peripheral part of the information recording area with high density. It is a figure which shows the example which has arrange | positioned the specific pattern in the center part of the information recording area with high density. It is a figure which shows the preferable example of a specific pattern. It is a figure which shows another preferable example of a specific pattern. It is a figure which shows the various examples of a specific pattern. It is a figure which shows the state which the specific pattern of the checkered pattern shown in FIG.8 (b) overlapped with the same pattern which appeared in the vicinity. It is a figure which shows the state with which the specific pattern of FIG. 6 overlapped with the same pattern which appeared in the vicinity. It is a figure which shows the state with which the specific pattern of FIG. 7 overlapped with the same pattern which appeared in the vicinity. It is a figure which shows an aspect when a blurring occurs so that each side of a black square will spread 1.4 times about the specific pattern shown in FIG.8 (g). It is a figure which shows the aspect when a blurring occurs so that each side of a black square will spread 1.4 times about the specific pattern of FIG. It is a figure which shows an aspect when a blurring occurs so that each side of a black square will spread 1.4 times about the specific pattern of FIG. In the specific pattern of FIG. 6, it is a figure which shows an aspect when one of the white eyes which comprise a center closed area | region has changed to the black eyes. It is a figure which shows the example of a processing flow for recognizing the specific pattern of FIG. When recognizing the specific pattern of FIG. 7, it is a figure which shows typically the method of making a round of the boundary of a 1st annular part and a 2nd annular part by the left method, and confirming a 2nd annular part. It is a figure which shows typically a mode when the area | region of the closed black dot is made a round by the left method of FIG. It is a figure which shows the example of a processing flow in order to recognize the specific pattern of FIG. It is a figure which shows the example which has arrange | positioned the specific pattern in the information recording area | region which uses a parallelogram as a grid. It is a figure which shows the block configuration of the information recording device used for enforcing a digital information recording method. It is a figure explaining the mapping method of making the bit information which should be recorded correspond to the grid of the area | regions other than the area | region which should arrange | position a specific pattern in an information recording area. It is a figure which shows roughly the processing flow for enforcing a digital information recording method. It is a figure which shows the bit map data obtained by reading a digital information record carrier with a reader. It is a figure explaining the 1st search method which searches the specific pattern of the center vicinity of an information recording area based on the position of the specific pattern along the outer periphery of an information recording area. It is a figure explaining the 2nd search method which searches the specific pattern of the center vicinity of an information recording area based on the position of the specific pattern along the outer periphery of an information recording area. It is a figure explaining the method of calculating | requiring another coordinate which comprises a parallelogram using a vector synthesis | combination using three known coordinates. It is a figure which shows the bit map data obtained by reading the specific pattern of FIG. 7 with a reader. It is a figure explaining the method of calculating the position of the arbitrary meshes in an information recording area based on the position of four specific patterns. It is a figure explaining the modification of the method of calculating the position of the arbitrary cell in an information recording area based on the position of four specific patterns. It is a figure explaining the further modification of the method of calculating the position of the arbitrary cell in an information recording area based on the position of four specific patterns. It is a figure which shows the block configuration of a digital information decoding apparatus. It is a figure which shows roughly the processing flow for demonstrating operation | movement of the said digital information decoding apparatus. It is a figure explaining the method to search the specific pattern of the four corners of an information recording area. It is a figure which shows the segment set with the digital information recording method of one Example of this invention. FIG. 36 is a diagram showing an example of an information recording area configured by arranging the segments of FIG. It is a figure which shows the example which has arrange | positioned the specific pattern in the center of a segment. FIG. 36 is a diagram showing another example of an information recording area in which the segments of FIG. 35 are arranged. FIG. 36 is a diagram showing still another example of the information recording area in which the segments of FIG. 35 are arranged. It is a figure which shows a mode that the information regarding an adjacent segment and the numbering information were recorded on each segment in the information recording area comprised as shown in FIG. It is a figure explaining the method of dividing digital information into unit information and recording on each segment. FIG. 36 is a diagram illustrating an example of an information recording area configured by arranging the segments of FIG. 35 and having a margin portion around the segment. It is a figure explaining how to make bit information which should be recorded correspond to each cell in a segment. It is a figure which shows the example which arrange | positions 16 segments according to a predetermined arrangement | sequence rule, and comprises an information recording area. (a) is an example of layout in a square, (b) is an example in which the number of horizontal segments is two, and (c) is an example in which the number of vertical segments is two. It is a figure which shows the block configuration of the digital information decoding apparatus of one Example of this invention. It is a figure which shows roughly the processing flow for enforcing the digital information decoding method of one Example of this invention. It is a figure explaining the method of taking in image information sequentially per segment. It is a figure explaining the method of taking in image information per line of a segment. It is a figure explaining the precision of the image information at the time of finding the upper left corner of an information recording area, and the precision of the image information at the time of reading the information recorded on each square in a segment. It is a figure which shows the external appearance of the zoom-up apparatus as an optical system. It is a figure which shows the example which arranged the specific pattern in the lower right corner of a rectangular block, and set the segment. FIG. 52 is a diagram showing an example of an information recording area that is configured by arranging the segments of FIG. 51 and has a margin portion along the upper side and the left side. It is a figure which shows the information recording area | region which was comprised by arranging another segment and the margin part produced along the upper side, the left side, and the right side. It is a figure which shows the example which the same pattern appeared in the vicinity of the outer periphery specific pattern in the vicinity of the upper side center of the information recording area. It is a figure which shows the example which made the blank part produced along the four sides of the information recording area | region in FIG. 42 a quiet area | region. FIG. 43 is a diagram showing an example in which the same pattern appears in the vicinity of the outer peripheral specific pattern at the center of the upper side of the information recording area shown in FIG. 42. FIG. 53 is a diagram showing an example in which the same pattern appears in the vicinity of the outer periphery specific pattern at the center of the upper side of the information recording area shown in FIG. 52. FIG. 53 is a diagram showing an example in which blank portions generated along the upper side and the left side of the information recording area shown in FIG. 52 are set as a quiet area. FIG. 53 is a diagram showing in detail a margin portion generated along the upper side of the information recording area shown in FIG. 52. FIG. 60 is a diagram showing an example in which a clocking pattern is provided in the margin part of FIG. 59. FIG. 56 is a diagram illustrating an example in which frame patterns connected to an outer periphery specific pattern are set in margins generated along the four sides of the information recording area as illustrated in FIG. 55. FIG. 56 is a diagram showing an example in which a frame pattern is set in the blank portion generated along the four sides of the information recording area as shown in FIG. 55 by the information recording method of one embodiment. It is a figure which shows the example which misrecognizes trying to find the specific pattern of an upper left corner. (a) An example of misrecognizing another outer peripheral specific pattern in the information recording area as a specific pattern in the upper left corner, (b) A pattern similar to the specific pattern in the information recording area in the upper left corner specific pattern (C) shows an example of misrecognizing a stain similar to a specific pattern outside the information recording area as a specific pattern in the upper left corner. It is a figure which shows the example which changed the presence or absence of the frame pattern in a margin part by the segment which exists in the four corners of an information recording area, and a segment other than that. It is a figure which shows the example which coded the number of the decimal number of 2 digits using the barcode technique (ITF) with respect to the area | region comprised by 27 horizontal x 5 vertical grid. It is a figure which shows the module structure at the time of coding the decimal number using ITF. FIG. 66 is a diagram illustrating an example in which the coding information of FIG. 65 is set to be reversed in black and white in the margin of FIG. 59 in order to clarify the boundary between the specific pattern and the barcode portion. FIG. 60 is a diagram showing an example in which index information is provided in the margin part of FIG. 59. (a) shows an example in which information is represented by the number, position, and thickness of the bar, and (b) shows an example in which information is represented by which line in the margin part three consecutive squares appear. FIG. 60 is a diagram showing an example in which index information is written in the margin of FIG. 59 without using a square as a unit. A thick bar is set to a 1.5-th grid width, and a thin bar is set to a 0.5-th grid width, and a 4-digit decimal number “3852” is coded using ITF. It is a figure which shows the example which recorded the arrow-shaped pattern with respect to the blank part. (a) shows an example in which an arrow-like pattern is recorded in a horizontally long margin, and (b) shows an example in which an arrow-like pattern is recorded in a vertically long margin. FIG. 60 is a diagram illustrating an example in which readable characters are provided in the blank portion of FIG. 59. (a) shows an example in which “SHARP” is written in upper case letters, and (b) shows an example in which “SHOIN” is written in upper case letters. FIG. 60 is a diagram illustrating an example in which readable characters are provided in the margin of FIG. 59 without using a square as a unit. It is a figure which shows the example which set information other than original recording information to the segment of the upper left corner. (a) shows an example in which a checker-like pattern is set for identifying the left and right sides, (b) shows an example in which an arrow indicating an upward direction is set, and (c) shows an example in which a readable character “WP” is set. . It is a figure which shows the example which set information other than the original recording information in the upper half of the segment of the upper left corner. It is a figure which shows the example which recorded the index information in the segment which exists in the upper left corner of an information recording area. It is a figure which shows the example which recorded the same index information on the segment which exists in the four corners of an information recording area. It is a figure which shows the example which recorded the same index information on the segment which exists in the upper left corner of an information recording area, and a lower right corner. It is a figure which shows the example which records index information over several segments of an information recording area. It is a figure explaining the digital information recording method which divides | segments an information recording area | region by a virtual square small block, and records according to a designation | designated pattern corresponding to a small block unit. It is a figure which shows the said small block in detail. FIG. 80 is a diagram showing a control pattern set in a small block at the upper left corner in FIG. 79. It is a figure which shows the pattern which rotated the control pattern of FIG. 81 90 degree | times. FIG. 80 is a diagram showing a processing flow for reading information recorded in the mode of FIG. 79;

Explanation of symbols

20 Recording surface 21 Rectangular block (area where original information should be recorded)
22, 22A, 22B, 22C,..., 22M, 72 Specific pattern 22a, 22b, 22c, 22d, 22e, 22f Divided pattern 23 Information recording area 41 Center portion 42 First annular portion 43 Second annular portion 27 Blank portion 28 Quiet Area 29A Frame pattern 132 Zoom-up device 133 Image sensor G Segment W Small block W1 Control pattern 91 Information decoding device 92 Reading device 93 Output device 94 Input unit 95 Data conversion unit 96 Output unit 97 Data conversion (decoding) algorithm 98 Reading device control apparatus

Claims (2)

In a substantially rectangular information recording area provided in a planar recording surface, a matrix-shaped parallelogram cell corresponding to the bit is virtually set, and the digital information to be recorded in each of the cells A digital information recording method in which a bright or dark mark that is optically recognizable is given according to digital information to be recorded in units of each cell, and the digital information to be recorded is recorded as a two-dimensional pattern. ,
A specific pattern formed by attaching the mark in a predetermined pattern to a plurality of cells connected to a specific shape so as to indicate a position in the recording surface is predetermined in the row direction and the column direction in the information recording area. A plurality of them are arranged in parallel with an interval of
The specific pattern arranged in a row direction or a column direction is arranged at a position that protrudes outside the information recording area with respect to at least one side of the information recording area,
A frame pattern extending along a circumscribed line with respect to the specific pattern is formed on the opposite side of the protruding specific pattern in a bay-shaped region surrounded by the side of the information recording area and the protruding side of the specific pattern. A digital information recording method, wherein the digital information recording method is arranged with a gap corresponding to at least one square. In a substantially rectangular information recording area provided in a planar recording surface, a matrix-shaped parallelogram cell corresponding to the bit is virtually set, and the digital information to be recorded in each of the cells A digital information recording method in which a bright or dark mark that is optically recognizable is given according to digital information to be recorded in units of each cell, and the digital information to be recorded is recorded as a two-dimensional pattern. ,
A specific pattern formed by attaching the mark in a predetermined pattern to a plurality of cells connected to a specific shape so as to indicate a position in the recording surface is predetermined in the row direction and the column direction in the information recording area. A plurality of them are arranged in parallel with an interval of
The specific pattern arranged in a row direction or a column direction is arranged at a position that protrudes outside the information recording area with respect to at least one side of the information recording area,
A clocking pattern in which bay-shaped regions surrounded by sides of the information recording region and the protruding opposite sides of the specific pattern are alternately marked with respect to a direction along the side of the information recording region A digital information recording method characterized by comprising:

Images