JPH0223485A - Picture signal processor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image signal processing apparatus that extracts and decodes a barcode area from scanned image data such as in a facsimile.

Conventional technology Conventionally, barcodes have been used in large numbers in logistics and other fields such as supermarkets, and most of them have scanning patterns in multiple directions, so that at least one scan on the barcode label used is correctly scanned. It is composed of (Nikkei Electronics 1980.12.22
．． p142 Types of Barcode Readers) Problems to be Solved by the Invention However, there are no conventional methods and apparatuses for extracting and correctly reading barcode areas from image data scanned in one direction, such as in facsimile scanning. The present invention provides an image signal processing device that can correctly extract a barcode area and decode it.

Means for Solving the Problems In order to achieve the above object, the technical solution of the present invention is as follows:
Input data is converted into binary data and stored in a storage means, and thin line portions of the binary data are enlarged and then thinned out. Barcode texture is determined using the thinned data and the determination result is expanded to create a bar code. After determining the area of the code and calculating the inclination and center point of the area, binary data is read out from the storage means in the direction of the inclination angle and the barcode is decoded.

According to the above configuration, the present invention separates the barcode from the background image by determining the texture of the barcode (determining the parallelism of the bars, etc.), and reads the binary data in the direction of the inclination angle of the barcode, thereby creating a barcode label. This allows decoding even if the input document is pasted in any direction on the input document.

Embodiment FIG. 1 is a block diagram of an image signal processing apparatus in an embodiment of the present invention. In FIG. 1, 1 is an input terminal for an input image signal (multilevel), 2 is a binarization circuit that binarizes the input image signal of input terminal 1, and 3 is a 1 (black) or 0 (white) is a thin line enlarging circuit that changes the width of only one pixel to two pixels; 4 is a data thinning circuit that thins out and outputs the thin line enlarged signal; 5 is a bar from the output signal of the data thinning circuit 4; A texture determination circuit 6 detects characteristics such as code parallelism and erases other signals. 6 expands the output signal 1 (black) of the texture determination circuit 5 by a certain area to make the barcode area all 1 (black). area determination circuit, 7
Reference numeral 8 indicates a cutout circuit that gates the output signal of the binarization circuit 2 with the output signal of the area determination circuit 6, and 8 is a binary data memory that stores the output signal of the cutout circuit 7. Note that a configuration in which the cutout circuit 7 is omitted and the output signal of the binarization circuit 2 is stored is also possible. 9 is a slope/center calculation circuit that calculates the slope and center point of the barcode from the output signal of the area determination circuit 6; 1o is the slope and center point of the barcode calculated by the slope/center calculation circuit 9; An address arithmetic circuit 11 calculates a data read address, and a barcode signal decoding circuit 11 decodes a barcode signal from data read from the binary data memory 8.

The operation of the above configuration will be explained below. The input image signal (multi-value) at the input terminal 1 is converted into a binary image signal by the binarization circuit 2. The binary image data is processed by a thin line enlarging circuit 3, for example, by reducing the width of 1 (black) or 0 (white) to at least 2.
Post-processing data thinning circuit 4 by securing pixels
To prevent the narrow black bar or white bar width of a barcode from disappearing even if the data is edited. The thin line enlarged data is processed by the data thinning circuit 4, for example, in the main scanning direction.
The data is thinned out to 1/2 in both the sub-scanning direction, and signals in other parts (for example, noise and other character information) are removed from the thinned data except for the part determined to be a barcode area by the texture determination circuit 5. Erase Black (1) → White (O
), the area determination circuit 6 fills out the entire barcode area.

However, the filled-in signal is interpolated (simple repetition of the same data) by twice as much data in both the main scanning direction and the sub-scanning direction by the amount thinned out by the data thinning circuit. The binary data output from the binarization circuit 2 is gated by the cutout circuit 7 using this painted signal and stored in the binary data memory 8. On the other hand, the slope/center calculation circuit 9 calculates the slope and center point of the barcode based on the painted signal area, and the address calculation circuit 10 reads out the barcode data from the binary data memory 8 along the slope angle. Calculate. The data read out from the binary data memory 8 at the read address is decoded by a barcode decoding circuit 11 to determine the barcode.

Each of the above configurations will be explained in more detail below. The binarization circuit 2 simply converts the input image signal into two at a certain threshold level.
This is a general circuit that converts into values. The thin line enlarging circuit 3 performs a process of enlarging, for example, one pixel width to two pixel widths, and does not enlarge pixels having a width of two pixels or more.

FIG. 2 is a diagram for explaining the thin line enlargement, and shows an example where the scanning line density of the image signal (data sampling pulse) is twice the width of the narrow bar code. In the same figure (a), the barcode part is scanned, 1-1 is a narrow black bar, 1-2 is a narrow white bar, 1-3 is a wide black bar, 1-
4 indicates the scanning part. The figure shows the relationship between the image signal in the scanning and the binarization threshold level,
2-1 is an image signal, and 2-2 to 2-4 are threshold levels.

The same figure (01 is the data sampling pulse, the same figure (d
) converts the image signal of 2-1 into 2 at the sampling pulse position.
This is a data string that has been converted into a value. 4-1 is binarized with the threshold of 2-2, 4-2 is binarized with the threshold of 2-3,
4-3 is the case of binarization using a threshold of 2-4. 4-2
In the data string, two pixels are secured for both the black bar and the white bar, but in 4-1, the black bar is one pixel, and in 4-3, the white bar is one pixel. However, in the former case, the adjacent white bar has 3 pixels, and in the latter case, the adjacent black bar has 3 pixels. This is clearly a natural case since the gaps from black bar to black bar and from white bar to white bar of the barcode do not change due to differences in threshold levels. In this embodiment, data conversion is performed to widen a barcode having a width of only one pixel to an adjacent barcode having three or more pixels.

FIG. 2(e) shows the scanning window for the data conversion, and the calculation is performed as follows.

When 1"20"21 '薊;・Ougi・Tsukasa;, set d22=1.

When the image signal sequences occur alternately in black and white and all the image signal sequences in the direction perpendicular to the image signal sequences are white or black, it is assumed that the lines are parallel (judgment output=1). The determination formula for the scanning window shown in FIG. 3 is shown below.

P53°P54'P55°P56°P57°P35°P
45°pss°P75°1 Next, the purpose of the data thinning circuit 4 is to reduce the size of the judgment mask of the post-processing texture judgment circuit 5, so that the narrow barcode width of the input image data can be secured by at least one pixel. Perform data thinning. For example, if the sampling density of an image is twice the width of a narrow barcode, a simple circuit configuration is used that thins out every other pixel and outputs it. (Thinning is done in both the main scanning and sub-scanning directions.) The texture determination circuit 5 is a determination circuit that focuses on the parallelism of barcodes. FIG. 3 shows an example of a scanning window used for the parallelism determination, and the numbers within the scanning window indicate pixel positions to be referred to for the parallelism determination. The judgment is based on the inherent characteristics of barcodes, that is, image signals P35 lined up in one direction within the scanning window.
°P45°P55°pas°P75°P53°P54°
P56°P5: 1P35°P45°P55”P65°
P75°P53°P54°F'se°P57 = IP
51 'P53°P55°P57°P59°P15°P
35°P75°pg5=tP51°P53°P55°P
57°P59°P15°P35°P75°P95°1P
15'P35°P55'P75°P95°P51''''P
53°P57'P59= 1P15°P35°pss°
P75°P95°P51°P53°P57°P5g =
1P33°P44°pss°pea°P77°P37
°P46°P64＠P73= IP33°PLEL”P5
5°pea°P77°P37°P46°P64°P73
= 1P37°P46°F'ss°P64°P73°
P33°P44°psa°P77 = 1P37°P4
6°P55°P64°P73°P33°P44°pea
°P77=1P11°P33'P55°P77°P99
°P19°P37°P73°Pg1 = 1' P11
°P33°P55'P77”P99°P19”P37”
P73°Pg1 = IP19°P37°P55°P7
3°P91°P11°P33°P77°P99°1 Bi1
91 Bi37"P556 Bi73°F91 °F11 F3
3°P77"P99=1'31"43°P55°P6
7°P79°'17°P36°P74°P93:1P3
1°P43°P55°P67°P79°P17°P36
°P74°Pg3 ” IP17°P36°P55°P
74°P93°P31°'43°P67°P79= 1
213”34°P55°P76°P97°P39”47
°P63°P71: 1P39°P47°P55°P63
°'71°P13"34°'76°P97=1
The specific configuration of image signal processing using a scanning window and the logic circuit configuration of the above-mentioned determination formula are common techniques, and their explanation will be omitted. Next, the area determination circuit 6 is a circuit that takes the logical sum of all the data within the scanning window and outputs it as an output signal, and the black (1) of the input image signal is substantially expanded by the size of the scanning window. The extraction circuit 7 is a circuit that takes the logical product of the output signal of the binarization circuit 2 and the output signal of the area determination circuit 6, and removes (or reduces) the background image of the barcode and then stores it in the binary data memory 8. This is to prevent unnecessary data from being given to the subsequent barcode decoding circuit. (This is an unnecessary circuit if there is no possibility of a judgment error in the barcode decoding circuit later)
The center calculation circuit 9 calculates the slope and center of the barcode from the black (1) data address of the output signal of the area determination circuit 6. An example of calculating the slope and center point when image data as shown in FIG. 4 is an input signal to the slope/center calculation circuit 9 will now be described. 12 in the same figure is the image data area (corresponds to the area of the binary data memory), 13 is the filled barcode area, there is no other background noise, the barcode is rectangular, and it is decoded when read in the long side direction. It shall be possible to convert

Four points of a rectangle (xl.

yl), (X2.y2), (X31 y3), (x4
．． y4), respectively (xl, yl); the point pyrnin(X
2. y2); Point g'y□8(x3.y
3); Point px□1n(x4・y4)i where X is minimum
+ya- in calculations below the point px□8 where X is maximum
When yβl>1xa−xβ, the calculation is performed by exchanging the X and y coordinates.

In the example in Figure 4, the slope is from the two long sides to the slope a ” (
y2 y3)/(x2 x3) or a = (y4-yl)/(X4-Xl) If the slope is reversed, a = (y2-y4)/(x2 X4)
Or a = (y3-yl)/(13Xl) The center (X□, y□) is zo: (x4-x3)/2 y□= (y2-yl)/2 4 rectangular points 'ymln' in Figure 5 ymax”xr
Each coordinate point of nln'px□8 (X l + yl)
+ (X 2+ 12) *(x3.y3), (x4.
y4) is shown. In Figure 4,
Reference numeral 14 denotes a starting point, and 15 a black signal detection unit which detects the first black signal from the input image signal-scanning line data. If there is no black signal, it is determined in step 16 whether the sub-scanning has ended, and if it has ended, the process returns to abnormal termination in step 17 in which the black signal cannot be detected, and if the sub-scanning has not ended, it returns to the black signal detection section in step 15.

When a black signal is detected in 15, it goes to each pointer initial value setting section in 18'ymln, pym, pxmin, p8□
-8 Set the first address where the black signal was detected to the X+X coordinate of each point. Next, in step 19, it is determined whether the sub-scanning has ended or not, and if it has ended, the process goes to abnormal end 17, and if it has ended, it goes to black signal detection section 20. The black signal detection section 2o detects a black signal from the input image signal of the next line-scanning line data. When a black signal is detected, the process goes to step 21 to update each pointer. Here, when the starting point of the detected black signal is p and the ending point is p, 3e, the X of point p, and the address yma of point p at the X coordinate.
Set x @, and the X address of point p is s of point ρ
If it is smaller than xminX address, set the address of point p at the x and y coordinates m In of point p, and

If e-res is larger than the X address of point p, the address of point p is set to the x and y coordinates of point max'xrnax. When the black signal detecting section 2o no longer detects the black signal, the process goes to 22 and ends normally. The address calculation circuit 1o calculates an address for reading data in accordance with the slope of the bar code after data input to the binary data memory 8 is completed. From the slope and center (X□, y□) to the center (X□, y□) obtained by the slope/center calculation circuit 9
A straight line y=ax+b passing through is found and data is read out according to the straight line. The read addresses x and y are x=1.2.3... y = a x + b 1):=yo aN.

The slope/center arithmetic circuit 9 and the address arithmetic circuit 10 constitute an arithmetic circuit using a microcomputer. The barcode decoding circuit 11 can apply conventional barcode decoding techniques as is, and decodes the barcode by, for example, comparing it with a code reference table.

Effects of the Invention As described above, the effect of the present invention is that the inclination direction of the barcode can be detected and the unidirectional scanning image data stored in the storage means can be read out and decoded in the inclination direction. This has great effects, such as being able to decode even if the barcode label is attached in any direction on the input document.

[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 an explanatory diagram of thin line enlargement of the main part of the same equipment, and Fig. 3 is an illustration of parallelism determination in the main part of the same equipment. Figure 4 is a conceptual diagram of the scanning window used, Figure 4 is a conceptual diagram of the filled-in barcode area in the main part of the device, and Figure 5 is an operation flowchart for calculating addresses of four barcode rectangular areas in the main part of the device. be. 3... Thin line enlarging circuit, 4... Data thinning circuit, 5... Texture determination circuit, 6...
. . . Area determination circuit, 9 . . . Slope/center calculation circuit, 9 . . . Address calculation circuit. Name of agent: Patent attorney Shigetaka Awano and 1 other person 2nd
Figure (d) -OOO100OINOOO-/” ---001+00m 7000-/”-00/110
1711100-/””(e) Main width direction

Claims (2)

[Claims] (1) A binarization means for binarizing the scan-resolved data of the original image including the rectangular barcode area, a thin line enlarging means for enlarging the thin line part of the binary data, and a thin line enlargement means for enlarging the thin line part of the binary data. a thinning means for selecting predetermined data; a texture determining means for determining the texture of the barcode from the thinned data; an area determining means for enlarging the texture determination output by a predetermined size and making the texture determination outputs continuous; a storage means for storing binary data;
calculation means for calculating the slope and center of the rectangular barcode from the area determination data; address calculation means for reading data from the storage means in the direction of the slope; and calculation means for calculating the barcode from the data read from the storage means. An image signal processing device comprising barcode decoding means for decoding. (2) Binarization means for binarizing the scan-resolved data of the original image including the rectangular barcode area, thin line enlarging means for enlarging the thin line part of the binary data, and the enlarged data of the thin line part. a thinning means for selecting predetermined data; a texture determining means for determining the texture of a barcode from the thinned data; an area determining means for enlarging the texture determination output by a predetermined size and making the texture determination outputs continuous; a clipping means for gate-outputting the binary data using region determination data; a storage means for storing the clipping data; a calculation means for calculating the slope and center of the rectangular barcode from the region determination data; An image signal processing device comprising: address calculation means for reading data from the storage means; and barcode decoding means for decoding a barcode from the data read from the storage means.