JPH0157393B2 - - Google Patents

Description

[Detailed description of the invention]

Industrial Application Field The present invention binary encodes information such as audio signals, reads the encoded code information, restores the recorded binary information from the read signal, and restores the original audio etc. The present invention relates to an information reading device that obtains information. Conventional structure and its problems Traditionally, audio information, product code information, etc.
Barcodes like the one shown in Figure 1 are often used as a printing encoding method to print in hexadecimal encoding, read the printed information, and restore the original audio information to the product code information. . However, this barcode method has the problem that the amount of information recorded is small because information is printed only one-dimensionally. Purpose of the Invention In view of the above-mentioned drawbacks, the present invention provides a record carrier that performs two-dimensional recording that can increase the amount of recorded information when recording information in binary form.
The present invention provides an information reading device that can restore information to its original state. Structure of the Invention The present invention provides binary information O to a first recording pixel and a second recording pixel.
The second recording pixel and the first recording pixel are arranged adjacent to each other in this order, and the binary information 1 is adjacently recorded in the row direction by the second recording pixel and the first recording pixel, and the recording in the row direction is performed. When the process is completed, there is a binary information recording area in which binary information is recorded again in the row direction after being shifted in the column direction, and on both sides of the row in the binary information recording area, whether the row is an odd numbered row or not. A synchronization signal area in which the first and second recording pixels are recorded in the column direction in an order depending on whether the row is an even number, and the area around the binary information recording and synchronization signal area, For a record carrier having a frame area recorded by one of the first or second recording pixels in order to identify a binary information recording area, the recording density is higher than the recording density in the record carrier. scanning means for scanning each region of the record carrier by optically fine scanning and converting it into an electrical signal; a binarizing means for converting the electrical signal converted by the scanning means into binary information; Image alignment means for detecting the first frame area in the row direction from the output binary information and outputting the detected frame area and a signal sandwiched between the frame areas; and means for accumulating the output binary information of the image alignment means. Then, a window consisting of a plurality of mutually adjacent pixels stored in the storage means is taken as one reading unit, information corresponding to a window set consisting of a plurality of windows is read from the storage means, and from the read information. The above object is achieved by providing a recognition means for restoring the binary information recorded on the record carrier. DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below. In addition, using FIG. 2 first, the pattern read by the information reading device in one embodiment of the present invention,
That is, the printing pattern of binary information will be explained. In FIG. 2, a frame area A is an area consisting entirely of black pixels, and this frame area A is an area having a constant width and consisting of _N2 recording pixels. Note that a recording pixel is the minimum recording unit when printing black or white. Although the value N ₂ can be any value greater than or equal to 1, in this embodiment, N ₂ =4. On the other hand, area B is a synchronization signal area to indicate whether it is the direction of the odd-numbered short side, that is, the direction of the arrow X, or the direction of the even-numbered short side. , white and black are adjacent to each other alternately,
It consists of N ₁ recording pixels, while for the even numbered pixels, as shown in FIG. 3b, starting with black, white and black are adjacent to each other alternately, and consisting of N ₁ recording pixels. This value N ₁ is equal to the number of windows in the window set used in the device described later. In the case of this embodiment, the number of windows in the window set is 3, and N ₁ =3. N ₁ mentioned above
FIG. 4 shows a part of the printed pattern when N 2 =3 and N ₂ =4. Area C in FIG. 2 is a binary information recording area for printing binary information such as audio signals and product codes. Binary information O consists of two recording pixels as shown in FIG. The pixels are printed and encoded in the order of black pixels and white pixels. For example, binary information
When O1O111O1 is print-encoded, it will be printed as shown in FIG. 5c. Note that the print recording density when printing binary information is arbitrary. Print recording density is determined from the printing technique and the reading density of the scanning device that scans the printed code information. For example, set the recording density to 4 pixels/
mm, when recording 32 bits of binary information per short side and recording 500 information areas along the long side, the dimensions of the printed information including the frame area are:
The size is 18.5 mm x 127 mm, and the amount of printed binary information is 16,000 bits. A recording density of 4 pixels/mm is fully possible with current printing technology, and the reading density of the scanning device that scans it is , even when scanning at a fineness four times the recording density, the rate is 16 pixels/mm, which is fully possible with current facsimile technology. FIG. 6 shows the print encoding of 80-bit binary information recorded in 8 bits on the short side and 10 lines on the long side. In addition, the table below shows 80 in Figure 6.
The table shows the binary information of bits.

[Table] The configuration of an information reading device according to an embodiment of the present invention that reads a print-encoded pattern as described above will be described below with reference to FIG. In FIG. 7, a scanning device 1 forms an image on a one-dimensional image sensor 4 via a lens system 3 in the short side direction of a printed code pattern 2, and sends a read image signal a to a storage device 6 via a drive circuit 5. Output. Note that the light source 7 is provided to illuminate the printed code pattern. Furthermore, the scanning device 1 is provided with a sensor 8 for detecting the amount of movement at the contact portion with the surface of the printed code pattern, and is scanned every time the scanning device 1 moves on the printed code pattern by the reading density interval amount. A pulsed scanning busy signal b indicating
Output to. When the scanning busy signal b is turned on, the storage device 6
A reading start signal c and a reading clock signal d are output. These signals c and d are generated by the control circuit 9. The drive circuit 5 of the scanning device 1 reads the image signal a read by the image sensor 4 based on the signals c and d and outputs it to the reading storage device 6. The read image signal a input to the storage device 6 is sent to the binarization circuit 1
0 is converted into a binary signal. Binarization circuit 1
0 is constituted by a conventionally well known analog comparator. The binarized signal e is sent to the frame area A by the image alignment circuit 11.
is detected, and the signals after the detected frame area A are stored in the memory 12. Incidentally, FIG. 8 shows a timing chart of each of the above-mentioned blocks. FIG. 8A shows an output signal a from the scanning device 1 when a portion 850 of the printed code pattern is scanned. The binarization circuit 10 compares the input value with a threshold value 851 (FIG. 8B), and outputs a binary signal e (FIG. 8C) in which white is at level O and black is at level 1. 8D is the same signal as the reading start signal c output to the scanning device 1, and the image alignment circuit 1 can know the start of one scan from this signal. The image alignment circuit 11 reads the binarized signal e using the reading clock signal d (FIG. 8) output to the scanning device 1, and converts it to level 1.
The signals are stored in the memory 12 from the time when K or more signals, that is, black signals, are detected. In the example of FIG. 9, the binarized signal e is stored in the memory 12 from the position of time T in the signal of FIG. 8 read by the signal d. The value K is determined from the relationship between recording density and reading density. For example, if the recording density is 4 pixels/mm and the reading density is 16 pixels/mm, a frame area made up of 4 recording pixels will have 16 reading pixels.
In this case, K=14, taking into consideration level changes during reading and quantization errors. In this way, the pixel alignment circuit 11
By providing this, in the case of manual scanning, even if the reading start position of the printed code pattern fluctuates or a margin area other than the printed code pattern is scanned, the accumulation start position is set to the frame area when storing in the memory 12. The memory capacity is sufficient to store the printed code pattern area when scanned at the allowed tilt. Now, returning to FIG. 7, the storage device 6 is the recognition device 1.
Two readout coordinate signals f, g sent from 3
The contents of memory 12 specified by are output. FIG. 9 shows the relationship between the print code pattern and the accumulated print code information. FIG. 9 shows how the scanning device 1
This is the case when the image is scanned at an angle of approximately 15°. Further, in this example, the reading density is four times the recording density. The value of the pixel stored in the storage device 6 is expressed as V(i, j), where i is the reading order in the short side direction and j is the reading order in the long side direction. For example, since the reading pixel 1000 in FIG. 9 is black and the order in the short side direction is i+1 and the order in the long side direction is j-3, it is expressed as V(i+1, j-3)=1. The storage device 6 outputs the contents of the memory 12 specified by the short side direction order signal 5 and the long side direction order signal g from the recognition unit 14 of the recognition device 13 as a signal h.
The recognition unit 14 restores the value of the recorded pixel (O for white, 1 for black) from which the printed code pattern has been recognized based on the recognition method described below, and outputs it to the information conversion unit 15. The information conversion unit 15 restores binary information converted into a printing code from the restored recorded pixel values and outputs it. The restoration uses windows and window sets to restore the printed code. Windows and window sets are defined as follows. (a) Four reading pixels {(i, j), (i+1, j),
(i, j+1), (i+1, j+1)} is called a window, and is expressed as W _{i,j using the first pixel positions i, j} . Also, the value of each reading pixel composing the window is V(i,j)=υ _i+j ,V(i+1,j)
=υ _i+1,j ,V(i,j+1)=υ _i,j+1 ,V(i+1,
j+1)=υ _i+1,j+1 (However, υ _p,q is O or 1, and p
is i or i+1, q is j or j+1), then _i,j is the value of window W _i,j and W~ _i,j = (υ _i,j, υ _i+1,
j,
υ _i,j+1 , υ _i+1,j+1 ). (b) A set of read pixels consisting of three windows is called a window set. The window set is expressed as WS _k,(i,j) . (However, k indicates the number of the window set, and (i, j) indicates the position of the first window in the window set indicated by number k.) The windows that make up the window set are located approximately on the center of the recording pixel. It is arranged so that it is located. Table 2 shows the position of each window corresponding to window set number k.

【table】

[Table] The 11 window sets shown in Table 2 above are for the case where the reading density allows a reading angle of up to about 20° when scanning is four times the recording density. The respective values of the three windows W _{~ i,j} , W~ _p,q , and W _u,v constituting the window set WS _{k,(i,j) are} W~ _i,j
，
When W _p,q and W _u,v , WS _k,(i,j) is the window set WS _k,(i,j)
WS _k(i,j) = (W~ _i,j , W~ _p,q , W~ _u,v
). Next, a procedure for recognizing a printed code pattern when the reading density is four times the recording density will be explained with reference to FIG. Step 101...Initialization step, i, j
are the reading position of the read image, that is, the reading coordinate signals f and g sent from the recognition device 13 to the storage device 6. x and y are the recording pixel positions of the recorded printing code, and are recording coordinate signals f' and g' sent from the recognition section 14 to the information conversion section 15. Step 102...Next, the first window in which all the read pixels constituting the window are 1 (black) is detected. Steps 103, 104, 105...The window position is updated. ENDi is the final pixel position in the direction of arrow X of the read image, and ENDj is the final pixel position in the direction of arrow Y. Step 106...Frame area A is detected.
LGTH(W~ _i,j ) is a function defined as follows. LGTH(W _i,j )=1 (however, W~ _i,j = W~ _i+1,j =...=
W~ _i
+1-1,j ≠W~ _i+1,j ) Step 107...The window is moved to the edge of the detected frame area A. Steps 108, 109...Check that the window position is at the end of the frame area A. Step 110...Move the window to the white pixel of the first synchronization signal. Function SCH ₁ (p, q | W ~ _{p, q} = (O,
O, O, O), i-1pi+1, j-1q
j+1) points the window at position (i, j) to arrow
Move within the range of i-1pi+1 in the direction of arrow Y and j-1qj+1 in the direction of arrow Y, and move W~ _p,q
This is a function that detects a window W _p,q where = (O, O, O, O) and sets its position (p, q) to a new (i, j). Step 111...W~ _p,q = by function SCH ₁
A check is made to see if a window position of (O, O, O, O) has been detected. Steps 112, 113, 114...Synchronization signal pattern is set. Here, 〓 is a ternary set of variables of the values of the window set, and is expressed in the order of the first window value, the second window value, and the third window value. Also, when the window value is (O, O, O, O), 0,
When the window value is (1, 1, 1, 1), it is expressed as 〓. Step 115: Using the given synchronization signal pattern, each window position of the window set used for restoration is determined. Function SCH ₂ (p, qk | WS~ _kp,q = 〓, i−
1pi+1,j-1qj+1) detects the window set WSk whose position is within the range of i-1pi+1, j-1qj+1 and whose value is 〓 from the window set of Table 2, and calculates the window position (i, j) and This is a function that determines the number k of the window set. Step 116...Check whether a window set has been detected, and if detected, proceed to Step 11.
In step 7, the scanning origin (XS, YS) of the first recording line is set and the restored recording pixel position and value are output to the information converter. Here, 〓(n) is the nth window set
When the value of the th window is 0, it means O, and when it is 〓, it means 1. Step 118: In order to restore the next recorded pixel, the window set is moved and the values of the window set to be compared are updated. Here, MOVE(WSk _i,j (2)) is a function that moves the window set WSk _i, j at position (i, j) to the second window position of the current window set. Furthermore, SL(〓) is a function that shifts the ternary set variable 〓 by one digit to the left. At this time, the third term is set to 0 as a temporary value. Step 119...Area C where the second and third recording pixels of the synchronization signal and binary information are printed and encoded.
Restores the value of the recorded pixel. Here the function SCH ₃
(p, q, 〓 | WS~ _{p, q} = 〓, MASK (1, 1,
O), i-1pi+1, j-1qj+1)
is the window set WSk _p,q at position (i, j) i−
When moving within the range of 1pi+1, j-1qj+1, detect a position where the value of the window set matches the value obtained by multiplying the given value 〓 by the mask given by the variable MASK, and combine that position and the value of the window set. This is a function that gives 〓. (However, MASK=(1, 1,
O) checks whether only the term indicated by 1, that is, the first term and the second term, match in the given 〓. Step 120... Check whether the value of the window set is detected. If detected, step 1
In step 21, the recorded pixel position is updated, and the restored recorded pixel value is output to the information converter 15. Step 122...It is checked whether the restoration of the values of the recorded pixels in the area where the binary information is print-encoded has been completed, and if it has not been completed, the restoration of the next recorded pixel is carried out. Step 12
4 or 131 to restore the synchronization signal. Step 132...It is checked whether the recording pixel restoration of all memory lines has been completed in the direction of the arrow Y. If it has not been completed, the window position (i, j) is set at the scanning origin of the next recording line in step 133. is updated, and the recorded pixels of the next recording line are restored. If the recording pixels of all the recording lines have been restored, the print code pattern recognition procedure is completed, and the information converter 15 follows the synchronization signal convention and the binary information print encoding convention. Then, the binary information is restored, and the restored binary information is output as the output h' of the recognition device 13. The above recognition procedure can cope with reading changes during manual scanning by determining the position of the window set for each recording line. Although the above recognition procedure has been described for the case where the reading scanning density is four times the recording density, it can also be applied to other reading densities by making the window positions of the window set correspond to the reading density. As described above, according to this embodiment, when binary information is printed and encoded, binary information O is encoded using white and black pixels, 1 is encoded using black and white pixels, and a synchronization signal and a frame area are further added. When reading and restoring the printed code pattern of a printed code, information printed with high density can be read by restoring it using a window and a set of windows. In addition, in this embodiment, the pixel colors in the printing encoding of binary information have been explained using white and black, but the pixel colors are not limited to white and black, and the two colors can be distinguished. Any combination of colors that is possible is fine. It is obvious that the invention can also be applied to printing methods such as those using magnetic ink. Furthermore,
It is also possible to increase the recognition rate by adding an error correction code during print encoding. Effects of the Invention As described above, the present invention can recover original information from a record carrier that performs two-dimensional recording that can increase the amount of recorded information when binarizing and recording information. It can be restored, and if manual scanning is performed, it can also respond to changes in the reading angle, which is very effective.

[Brief explanation of drawings]

FIG. 1 is a plan view of a barcode, which is one of the printing encoding methods, FIG. 2 is a plan view of a printing code pattern used in an information reading device in an embodiment of the present invention, and FIGS. 3a and 3b are FIG. 4 is a plan view of the frame area of the printed code pattern and the synchronizing signal pattern, and FIGS. 5 a to 6 are for explaining the binary information. 7 is a block wiring diagram of an information reading device according to an embodiment of the present invention, FIG. 8 is a timing chart of the same device, and FIG. 9 is a plan view of the printed code pattern when the scanning device is tilted. Figures 10a to 10d, which are diagrams showing the relationship between the printed code pattern and the read pixels when scanning the pattern, are flowcharts of the recognition procedure in the same apparatus. 1...Scanning device, 6...Storage device, 10...2
Value conversion circuit, 11... Image alignment circuit, 12... Memory, 13... Recognition device, 14... Recognition unit, 15...
...Information conversion department.

Claims (1)

[Claims] 1 Binary information 0 is adjacent to the first recording pixel and second recording pixel in this order, and the binary information 1
are adjacent to each other in this order by the second recording pixel and the first recording pixel, and sequentially recording in the row direction,
When the recording in the row direction is completed, the binary information recording area shifts in the column direction and the binary information is recorded again in the row direction, and on both sides of the row in the binary information recording area, the row is the odd numbered a synchronization signal area in which the first and second recording pixels are recorded in a column direction in an order according to whether the pixels are in a row or an even numbered row; and an area for recording binary information and a synchronization signal. For a record carrier having a frame area around which recording is performed by one of the first or second recording pixels in order to identify the binary information recording area, scanning means for scanning each area of the record carrier by optically finer scanning than the recording density and converting it into an electrical signal; and 2 for converting the electrical signal converted by the scanning means into binary information.
an evolving means; an image aligning means for detecting the first frame area in the row direction from the output binary information of the binarizing means and outputting the detected frame area and a signal sandwiched between the frame areas; and the image aligning means. Means for accumulating output binary information of the means; and a window consisting of a plurality of mutually adjacent pixels accumulated in the accumulation means are taken as one reading unit, and information corresponding to a window set consisting of the plurality of windows is read by the above-mentioned An information reading device comprising: a recognition means for reading from a storage means and restoring binary information recorded on a record carrier from the read information.