JPH0223488A - Picture signal processor - Google Patents

Abstract

PURPOSE:To obtain a picture signal train equivalent to the orthogonal scanning of a bar code and to decode the bar code by collating the run length of a read picture signal with a stored run length and fetching the picture signal along the center line of the bar code and having a prescribed pitch. CONSTITUTION:The output of a binary picture signal generating means 1 is stored in a memory 2. The pattern of the train of the run length is coded and stored in a run length code storing means 3. A run length counting means 4 counts the number of continuous white picture elements and creates white run length data, and a fine/heavy width code generating means 5 counts the start position and the end position of the picture elements of the run and informs a pattern area deciding means 6 of the counted result. The decoding means 6 reads the run length code from the storing means 3, compares the counted result with the read run length code, and generates a propriety signal. A pattern area picture signal generating means 7 replaces the signals between the start position and the end position with black picture signals only when the propriety signal informs the means 7 that the compared result is proper. A center line detecting means 8 obtains the least square approximation straight line from a pattern area picture signal and makes the obtained line into the center line, and finally, the picture signal having the prescribed amount of width is fetched from the storing means 2 along the center line and made into the aimed picture signal in an inclined picture signal generating means 9.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image signal processing device for decoding barcodes in raster scanned image signals.

2. Description of the Related Art In recent years, information processing systems using electronic computers have become widespread, and barcode reading devices are widely used as data entry devices for these systems. These barcode reading devices are hand-scanned devices in which the operator moves the reading device perpendicular to the bars of the barcode, or the barcode is placed within a predetermined window and scanning lines are run in multiple directions. In this method, an image signal obtained by scanning with a scanning line that crosses the bar perpendicularly is decoded.

Problems to be Solved by the Invention On the other hand, image processing devices and systems that capture image signals obtained by raster scanning an image and perform various types of processing are becoming widespread. When there is a barcode in the document image of these image processing devices and systems, it is very effective and effective for these image processing devices and systems to decipher the code and manage and utilize it as image attribute information. It has a wide range of uses.

However, it is rare for the image processing device's original reading scanning direction to be orthogonal to the direction of the barcode bars in the original, and therefore there are extremely few opportunities to extract an image signal sequence perpendicular to the bars directly from the reading area side signal sequence. .

The present invention detects the barcode area even if the barcode is tilted by a predetermined angle from the image signal read by raster scanning, and obtains an image signal sequence equivalent to an image signal sequence scanned orthogonally to the bar. The purpose is

Means for Solving the Problems In order to solve the above problems, the present invention provides a binary image signal generation means for generating a binary image signal, a binary image signal storage means for storing the binary image signal, and a predetermined method. a run length code storage means for storing a run length code; a run length counting means for counting white and black runs of the binary image signal to generate run length data; narrow/wide code generation means for converting into a code indicating a wide range; pattern area determination means for comparing the run length code with the narrow/wide code to determine whether or not the run length code is a predetermined pattern area; a pattern area image signal generating means for generating an image signal that is black or white only when the image signal is black or white; a center line calculating means for calculating the center line of the pattern area image signal; It is equipped with tilted image signal generation means for outputting an image signal.

Operation According to the above configuration, the present invention first stores the binary image signal generated by the binary image signal generating means in the binary image signal storage means for the subsequent stage. Further, in advance, the run length code storage means encodes and stores a pattern of run length columns when a predetermined number of black bars in the barcode are noted. That is, the shape of a barcode is predetermined by standards such as JIS, and in this example, the ratio of the bar width and the gap between characters is a narrow bar. 0 Thick bar・・・・・・・・・・・・・・・2.14 Gap between characters・・・2.32, and expressing one character with 7 bars, 1
It has various characteristics, such as the fact that there are only two wide bars in the characters. Focusing on these characteristics, patterns in which a combination of a narrow bar, a wide bar, and a gap between characters occur are coded and stored, for example, as 01 for a narrow bar and 1 for a wide bar and a gap between characters.

On the other hand, the run length counting means counts the number of consecutive white pixels (or black pixels) of the binary pixel signal from the binary pixel signal generating means and sets it as the white run length (or black run length). This counting is repeated until the run length data is sequentially generated.

Next, the narrow/wide code generation means sequentially extracts run length data and counts the pixel start position of the first run and the end position of the last run for a predetermined number of run length data. In addition to notifying the pattern area image signal generation means, a narrow/broad code is generated in which a predetermined number of run length data are set to O1 for the narrow run length and 1 for the wide run length, and is notified to the pattern area determination means. . The pattern area determining means reads out the run length code from the run length code storage means, compares it with the narrow and wide codes, and notifies the pattern area image signal generation means of whether or not they match. The pattern area image signal generating means sends a black image signal (or white image signal) to the line buffer initialized in advance between the start position and the end position only when a conformity notification is received from the previous stage for each run length data. signal) and repeats the operation until the end of the line to generate an image signal and use it as a pattern area image signal.

Next, the center line detection means associates the pattern area image signal with a coordinate system in which the main investigation direction is the X axis and the sub investigation direction is the Y axis, and points Pi (xi
, yi) and the least squares approximation straight line y==a・x+b ・・・・・・・・・・・・
...(1) is determined, and the straight line of equation (1) is set as the center line.

Finally, in the tilted image signal generation means, an image signal having a predetermined width along the center line is extracted from the binary image signal storage means and is used as a target image signal.

In this way, the present invention can detect the barcode area even if the barcode is tilted by a predetermined angle from the image signal read by the rask scan, and obtain the image signal scanned with the scanning line orthogonal to the bar. be.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of an image signal processing device according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a binary image signal generating means for converting the reading signal of the Tsukku code into a binary image signal;
2 is a binary image signal storage means for storing the binary image signal; 3;
4 is a run length code storage means in which a code of a predetermined run length is stored in advance; 4 is a run length counting means for counting white and black runs of the binary image signal to generate run length data; 5 is a run length of a predetermined amount. Converts long data into codes indicating narrow and wide widths.
a wide code generation means; 6 a pattern area determination means for comparing the run length code with the narrow/wide width code to determine whether or not it is a predetermined pattern area; 7 generates a black image signal only in the case of a predetermined pattern area; pattern area image signal generation means for
8 is a center line calculation means for calculating the center line of the pattern area image signal; 9 is an inclined image signal generation means for extracting an image signal from the binary image signal storage means 2 along the center probability; 10 is an image to be generated; It's a signal. In this embodiment, the run length code storage means 3, the run length counting means 1, the narrow/wide code generation means 5, the pattern area determination means 6, and the pattern area image signal generation means 7 constitute the pattern area detection means. do. In addition, in this embodiment, the binary image signal has white as 0 and black as 1.
It is assumed that the scanning area is 200 mm x 300 M, the scanning line density is 10 lines/order, and the main specifications of the barcode are as shown in Table 1.

Furthermore, the entire pattern area determining means is configured to evaluate seven bars.

In the above configuration, first, the binary image signal generating means 1
It is composed of a scanner using a D array sensor, and a reading start signal, a line synchronization signal, a binarized image signal, and a pixel synchronization signal are notified to the binary image signal storage means 2 and the run length counting means 4.

In the binary image signal storage means 2, the binary image signal is stored for the subsequent stage.

Next, the occurrence pattern of narrow bars and wide bars (including gaps between characters) starting from a black bar is stored in advance in the run length code storage means 3. The pattern is shown in Figure 2 when there is one large bar, and as shown in Figure 3 when there are two large bars.
In the figure, if there are 3 large bars, in Figure 4 there are 4 large bars.
When there are 5 thick bars, the pattern is shown in Figure 5, and when there are 5 wide bars, it is as shown in Figure 6. Each pattern is stored in the form of a binary code where the narrow bar is 0 and the wide bar is 1. has been done.

Next, the run length counting means 4 counts white runs and black runs, assuming that the beginning of the line is white, and notifies the narrow/wide code generation means 5 of the counts. In this case, odd numbers mean white runs, and even numbers mean black runs.

Next, the functions of the narrow/wide code generating means 5 and the pattern area determining means 6 will be explained with reference to FIG. 7 showing a more detailed configuration. In FIG. 7, 11 is a binary image signal;
3 is a run length code storage means, 4 is a run length counting means, 51
52 is a group of delayed run length registers that stores the delayed run length data of 7 pieces of run length data, 52 is a total run length register that stores the total value of 7 pieces of run length data, and 53 is a group of delayed run length registers that stores the delayed run length data of 7 pieces of run length data. A pixel position counter 54 counts and stores the pixel start position of the first run and the end position of the last run, and 54 is a first narrow bar that generates the narrow bar and wide bar code when there is one thick bar. 55 is a second narrow/wide code generation means for generating a narrow/wide code when there are two wide bars; 56 is a narrow/wide code when there are three wide bars. 57 is a fourth narrow/wide code generation means that generates a narrow/wide code when there are four wide bars; 58 is a code generating means for generating narrow/wide codes when there are four wide bars; A fifth narrow/wide code generation means for generating a narrow/wide code when there is a wide bar;
62 is a second pattern area determining means that evaluates the narrow width/wide code when there are two wide bars;
Reference numeral 63 denotes a third pattern area determining means for evaluating narrow and wide codes when there are three wide bars, and 64 a fourth pattern area for evaluating narrow and wide codes when there are four wide bars. 51.52 is a determining means, 65 is a fifth pattern area determining means for evaluating narrow and wide codes when there are 5 wide bars, 7 is a pattern area image signal generating means, and 51.52
．． 53.54.55.56.57.58 constitutes the narrow/wide code generation means 5, and 61.62.63.64.6
5, the pattern area determining means 6 has a configuration j-. The pixel position counter 53 receives target run length data 1i (i is an even number)
The total run length up to the previous time is counted as the pixel start position, and the total run length up to the i+6th run length data is counted as the pixel end position, and the result is notified to the pattern area image signal generation means 7.

Next, the delay run length register group 51 operates as shown in FIG. 8 as follows. That is, the delay run length register group consists of seven registers r1, r2, r3, r4, r5,
It consists of r6 and rl, and the run length data column is II.
Then 11 for rl, 11+1 for r2, I i+2 for r3, l i+a for r4, 11+4 for r5
, 11+5 for r6, ! for rl! Store i+6.

In addition, the total run length register 52 stores the run length total value (ρ) as ρ=ll-1-1i+1-1-1i+z-1-1i+
Count and store as a+Ii+4-1-1i+5-4-1 i+6. Next, in the first narrow/wide bar code generation means 54, the run length total value (ρ) is the run length total when there is one wide bar in the narrow bar/wide bar determination table in Table 2. It is determined whether the upper limit and lower limit of the value (ρ) are satisfied. If not satisfied, write oooooo in binary
The oo code is passed to the first pattern area determining means 61 in the subsequent stage.
Notify.

In this example, the upper limit of the run length total value (ρ) is set to a value that has a margin of at least 1.42 times the number of pixels that can be read at a predetermined density by scanning lines perpendicular to seven bars. By setting , barcodes that are tilted within 45 degrees are allowed. If satisfied, continue arching registers r1, r2
, r3, r4, r5, r6, r7 are the upper and lower limits of narrow bars or the upper limits of wide bars when there is one wide bar in the thin bar/thick bar judgment table in Table 2. , it is determined whether the lower limit value is satisfied. If the value of any register does not satisfy any of the upper and lower limits, that is, for any k (l≦≦7), rkQ value < ρ/18 or 6ρ/18 (rkO value) notifies the binary oooooooo code to the first pattern area determination means 61 at the subsequent stage.Also, if any of the conditions is satisfied, if the narrow bar is satisfied, that is, the value of ρ/18≦rl((3ρ /18 satisfies the 01 large bar, that is, 3ρ/
A 7-digit binary code that satisfies 1 if is≦rkO value≦6ρ/18 is notified to the first pattern area determining means 61 at the subsequent stage. Further, second narrow/wide code generation means 55, third narrow/wide code generation means 56, fourth narrow/wide code generation means 57, fifth narrow/wide code generation means 58 A similar determination is made in the second pattern area determining means 62 and a binary code is generated.
The pattern area determining means 63, the fourth pattern area determining means 64, and the fifth pattern area determining means 65 are notified. Next, the first pattern area determining means 61 reads the pattern code shown in FIG. 2 from the run length code storage means 3 and compares it with the narrow/wide code from the first narrow/wide code generating means 54. If they match, the pattern region image signal generating means 7 at the subsequent stage is notified of the match, and if they do not match, the pattern area image signal generating means 7 at the subsequent stage is notified of the non-match. Further, the second pattern area determining means 62, the third
The pattern area determining means 63, the fourth pattern area determining means 64, and the fifth pattern area determining means 65 perform similar evaluations and notify the subsequent pattern area image signal generating means 7 of conformity or nonconformity.

Next, in the pattern area image signal generation means 7, an output line buffer (not shown) is initialized at the beginning of the line, and the first pattern area determination means 61 at the previous stage,
Second pattern area determining means 62, third pattern area determining means 63, fourth pattern area determining means 64, fifth
When there is a conformity notification from any of the pattern area determination means 65, the line buffer in the range of the start position and end position of the pixel position counter 53 is replaced with black.

By repeating the above operations until the line is completed, a pattern area image signal for one line is generated, and the generation of the pattern area image signal is repeated until the entire area of the document is completed.

Next, the centerline detection means 8 uses a microcomputer to perform the following calculations to determine the centerline and center of the pattern area. That is, the pattern area image signal is made to correspond to a coordinate system in which the main operation direction is the X-axis and the sub-scanning direction is the Y-axis, and the center of the black point Pi (xi, yi) in the X-axis direction is defined by a least square approximation straight line. The coefficients a and b of y=a・x + b are converted into binary values by performing the memory address calculation of N(ゞΣx i 2) −(iΣX1) 2. An image signal is taken out from the image signal storage means 2 and used as an output signal sequence of the apparatus.

In other words, from the width of the barcode, the scanning line density, the average value in the It is calculated using equations (6) and (7).

ΔX=l/Vl±a2 ・・・・・・・・・
...(6) The point sequence Qj (xQj, yqj) is
8) Calculate using formula.

...Calculate according to (5). This calculation is realized by a program for the microcomputer shown in FIG.

In this program, x [] is a point sequence P! X coordinate value, y()
is a point sequence P! n is the number of point sequences, Xbar is the average value in the X-axis direction, a is the slope coefficient of the least squares approximation line, and b is the displacement coefficient of the least squares approximation line.

Finally, the tilted image signal generation means 9 also extracts image signals from the binary image signal storage means 2 based on the coordinate values (XQJ+yqj) of the point sequence QJ obtained in this way and uses them as the output signal sequence of the apparatus.

In this embodiment, limitations are set on the scanning line density and the main specifications of the barcode, but these limitations can be sufficiently implemented even if changed, and the center line detection means 8 and the tilt image signal Although the generating means 9 is implemented using a microcomputer, these means can also be implemented using a logic circuit or an external storage device.

Effects of the Invention As described above, the present invention records the barcode run length pattern in advance, and compares the run length of the image signal read by the rask scan with the above-mentioned stored pattern, thereby determining the barcode area. By detecting the area, determining the center line of this area, and extracting image signals at a predetermined pitch along the center line, it is possible to obtain an image signal sequence equivalent to orthogonal scanning to the barcode. By employing the image signal sequence obtained in this way as an input signal to a conventional barcode decoding device, it becomes possible to decode the barcode, and the effect is very large.

[Brief explanation of the drawing]

FIG. 1 is a block configuration diagram of an image signal processing device according to an embodiment of the present invention, FIG. 2 is a pattern diagram when there is one wide bar in the main part of the device, and FIG. 3 is a pattern diagram when the wide bar is one. Figure 4 is a pattern diagram when there are 2 wide bars, Figure 5 is a pattern diagram when there are 4 wide bars, and Figure 6 is a pattern diagram when there are 3 wide bars. A pattern diagram in the case of 5 pieces, FIG. 7 is a block diagram of the same pattern area detection means,
FIG. 8 is a diagram showing the relationship between the delayed run length register group and the total run length register, and FIG. 9 is a diagram showing a program for determining the same center, center, and center line. DESCRIPTION OF SYMBOLS 1... Binary image signal generation means, 2... Binary image signal storage means, 3... Run length code storage means, 4... Run length counting means, 5... Narrow width/wide width Code generation means, 6...
- Pattern area determination means, 7... Pattern area image signal generation means, 8... Center line calculation means, 9... Tilt image signal generation means. Name of agent: Patent attorney Shigetaka Awano and one other person

Claims (5)

[Claims] (1) Binary image signal generation means for generating a binary image signal from a barcode reading signal, binary image signal storage means for storing the binary image signal, and a code of a predetermined run length. A run length code storage means and a white/white color of the binary image signal
run length counting means for counting black runs and generating run length data; narrow/thick code generation means for converting a predetermined amount of run length data into codes indicating narrow width and wide width; pattern area determining means for comparing narrow and wide codes to determine whether the area is a predetermined pattern area; pattern area image signal generating means for generating an image signal that is set to 1 or 0 only in the case of a predetermined pattern area; An image signal processing device comprising: center line calculation means for calculating a center line of a pattern area image signal; and tilted image signal generation means for extracting an image signal from the binary image signal storage means along the center line calculation. (2) The run length code storage means stores in advance an n-digit binary or n-ary code in which the narrow bar of a predetermined barcode is 0, the wide bar is 1, and the character gap is 1. The image signal processing device according to claim 1, characterized in that: (3) The narrow/thick code generation means generates the maximum and minimum values of the total run length (ρ) corresponding to the predetermined number n of bars, the maximum and minimum values of the narrow bars, The maximum value and minimum value of the thick bar including the gap between characters are determined as a function of the total value of run length (ρ), and the arrangement of n runs of the binary image signal is evaluated using the maximum value and minimum value. 2. The image signal processing apparatus according to claim 1, wherein the image signal processing apparatus generates a binary or n-ary code in which 0 corresponds to a narrow bar and 1 corresponds to a wide bar including a gap between characters. (4) The run length code storage means stores in advance an n-digit binary or n-ary code in which the narrow bar of a predetermined barcode is 1, the wide bar is 0, and the character gap is 1. The image signal processing device according to claim 1, characterized in that: (5) The narrow/wide code generation means generates the maximum and minimum values of the total run length (ρ) corresponding to the predetermined number n of bars, the maximum and minimum values of the narrow bars, and the maximum value and minimum value of the thick bar including the inter-character gap are determined as a function of the total value of the run length (ρ), and the arrangement of n runs of the binary image signal is evaluated using the maximum value and minimum value. 2. The image signal processing apparatus according to claim 1, wherein the image signal processing apparatus generates a binary or n-ary code in which 1 corresponds to a narrow bar and 0 corresponds to a wide bar including an inter-character gap.