JPH0223484A - Picture signal processor - Google Patents

Abstract

PURPOSE:To decode a bar code from a label stuck in an arbitrary direction by separating the bar code from its background using the density contrast difference between the white bar and the black bar of the bar code and reading binary information in the inclining direction of the bar code. CONSTITUTION:The multivalued input picture signal of a terminal 1 is converted into the outline signal of a picture in an intra-window maximum level difference arithmetic circuit 2 and a binarizing circuit 3, the outline signal is expanded in an area deciding circuit 4, and the whole of a bar code area is painted out in black '1.' Further, the input picture signal is binarized in a binarizing circuit 5, gated in a segmenting circuit 6, and stored in a binary data memory 7. On the other hand, an inclination and center arithmetic circuit 8 obtains the inclination and the center of the bar code from the signal to paint out the bar code area, an address arithmetic circuit 9 reads the data from the memory 7 according to the inclination, and a decoding circuit 10 decodes the read data and decides the bar code. The bar code can be decoded even when the label is stuck in the arbitrary direction in the above-mentioned composition of the title device.

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 In the past, many barcodes have been used in logistics and other fields such as supermarkets, and most of them have scanning patterns in multiple directions, and it is necessary to correctly scan at least 61 scans on the barcode label used. It is configured to do so. (Nikkei Electronic, 2.1980.t2,
22. P142 Types of Barcode Leagues) Problems to be Solved by the Invention However, there are no conventional examples of methods and devices 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 read and decode a barcode area.

Means for Solving the Problems In order to achieve the above object, the technical solution of the present invention is as follows:
Detecting the outline of the image data based on the image signal level difference within a scanning window that scans the input data, and cutting out the input data with barcode area data filled by expanding the outline part and storing it in a storage means, After calculating the inclination and center point of the cut-out data, 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 using the density contrast difference between the white bar and the black bar of the barcode, and reads the binary data in the direction of the inclination angle of the barcode. This allows decoding even if the code label is attached 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), and 2 is an input terminal for inputting an input image signal of input terminal 1.
an in-window maximum level difference calculation circuit that scans with a scanning window of Xn, calculates the maximum level difference of data within the scanning window, and sequentially outputs the result
4 is a binarization circuit that binarizes the output signal of the maximum level difference calculation circuit 2 within a window using a threshold of a certain level, and 4 is a bar code that expands the output signal 1 (black) of the binarization circuit 3 by a certain area. A region determination circuit that makes the region all 1 (black); 5 is a binarization circuit that binarizes the input image signal of input terminal 1 with a threshold of a certain level; 6 is a region determination circuit for the output signal of the binarization circuit 5; circuit 4
7 is a binary data memory that stores the output signal of the extraction circuit 6; 8 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 4; 9 is the slope/center calculation circuit 8
1o is a barcode signal that decodes the barcode signal from the data read from the binary data memory 7; 1o is a barcode signal that decodes the barcode signal from the data read from the binary data memory 7; This is a decoding circuit. (In the above configuration, the cutout circuit 6 is eliminated and the 2
A configuration in which the output signal of the digitizing circuit 5 is stored in the binary data memory 7 is also possible. ) In the above configuration, its operation will be explained below. The input image signal (multi-value) of the input terminal 1 is converted into an image contour signal by the in-window maximum level difference calculation circuit 2 and the binarization circuit 3, and the contour signal is expanded by the area determination circuit 4 to determine the barcode area. Fill all of them with black (1). Further, the input image signal is binarized by a binarization circuit 5, and the binary data output from the binarization circuit 5 is gated by a cutting circuit 6 using the filled signal and stored in a binary data memory 7. On the other hand, a slope/center calculation circuit 8 calculates the slope and center point of the barcode from the painted signal, and an address calculation circuit 9 calculates an address for reading barcode data from the binary data memory 7 along the slope angle. do. The data read out from the binary data memory 7 at the read address is decoded by the barcode decoding circuit 10 to determine the barcode.

Each of the above configurations will be explained in more detail below. The intra-window maximum level difference calculating circuit 2 performs the following calculations on the scanning window (A) or (a) shown in FIG. 2, and outputs the difference S between the maximum value and the minimum value.

S=max(DI) −rnlo(Dll1=A+B+
c+D For the scanning window (A), the reference pixel (A) is
-D), a large contour signal S can be obtained. The binarization circuit 3 is a circuit that binarizes the contour signal S at a certain threshold level. Generally, barcode labels have a large density contrast ratio between white bars and black bars, so the contour signal S becomes large, and therefore the threshold level can be set high, making it easy to separate the contour signal from the background image. The specific configuration of image signal processing using a scanning window is a common technique, and its explanation will be omitted. The area determination circuit 4 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 contour signal (1) that is the output of the binarization circuit 3 is expanded by the size of the scanning window. Become. If the size of the scanning window is a circular mask with a diameter of -, where r is the width of a wide black or white bar, the barcode area can be filled. The binarization circuit 5 is a general circuit that simply binarizes the input image signal at a fixed threshold level.

The extraction circuit 6 is a circuit that takes the logical product of the output signal of the binarization circuit 5 and the output signal of the area determination circuit 4, and after removing (or reducing) the background image of the barcode, the output signal is stored in the binary data memory 7.
This is to avoid giving unnecessary data to the later barcode decoding circuit 10 (this circuit is unnecessary if there is no possibility of a judgment error in the later barcode decoding circuit 10).

The slope/center calculation circuit 8 calculates the slope and center of the barcode from the black (1) data address of the output signal of the area determination circuit 4. An example of calculating the slope and center point when image data as shown in FIG. 3 is an input signal to the slope/center calculation circuit 8 will now be described. 11 in the same figure is the image data area (corresponds to the area of the binary data memory), 12 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 The four points of the rectangle are (xl, yl), (X2.y2)
, (xa, y3), (X4, y4), respectively ("1.Vl); point ml where y is the minimum.

(x2, y2); Point pymax(
X3. Y3); Point 1” where x is the minimum
n(xa,'a); point pxrn where x is maximum
In the calculation below ax, l yrn ynl>IXm
When xn, the calculation is performed by exchanging the X and Y coordinates.

In the example in Figure 3, the slope is from the two long sides to the slope a = (y
2-y3)/(X2-X3) or a=
(y4 yt)/(xa xl) If the slope is reversed, a= (y2-ya)/(X2-X4)
Or a= (y3-yl)/(X3-XI) The center (Xo, yo) is xo= (X4-X3)/2 yo= (y2-yl)/2 In Figure 4, there are four rectangular points Pymln + Pyrnax T
Each coordinate point of Pxrnln +pxmax (xl, yl
), (x2.y2).

The operation flow for calculating (X3, y3') and (X41 y4) is shown. In FIG. 4, 13 is a starting point, and 14 is a black signal detection section that detects the first black signal from the data of one scanning line of the input image signal. If there is no black signal, it is determined in step 15 whether the sub-scanning has ended, and if it has ended, the process returns to abnormal termination in step 16, where no black signal can be detected, and if the sub-scanning has not ended, it returns to the black signal detection unit in step 14.

When a black signal is detected in 14, each pointer initial value setting section 17 is activated.Pymln + pymax + pxml
n 豐pxrn□Set the first address where a black signal was detected in the "+y" coordinate of each point.Next, it is determined in 18 whether the sub-scanning is finished, and if it is finished, it goes to 16 abnormal end, and if it is not finished, it goes to 19 The black signal detection section 19 detects a black signal from the data of one scanning line of the input image signal of the next line.

When a black signal is detected, each of the 20 pointers is updated.

Here, when the start point of the detected black signal is Pm and the end point is po, set the address of point ps to the x and y coordinates of point pym□, and set the X address of point pS to the
If it is smaller than the address, set the address of point -1 to the x and y coordinates of point pxmln, and if the X address of point p is larger than the X address of point pxrn□, point 1)x□
@x (7) Set the address of point -〇 in the x and y coordinates. When the black signal detecting section 19 no longer detects the black signal, the process goes to 21 and ends normally. The address calculation circuit 9 calculates an address for reading data in accordance with the slope of the bar code after data input to the binary data memory 7 is completed. From the slope and center (xo, yo) obtained by the slope center calculation circuit 8,
Find the straight line y=a+b passing through "10" and read out the data according to the straight line.The read address x and y are x=1.2.3... y=a^+b b = yo"'" aXQ The tilted fist center calculation circuit 8 and the address calculation circuit 9 constitute a calculation circuit using a microcomputer.The barcode decoding circuit 10 can apply conventional barcode decoding technology as is, for example, by comparing with a code reference table, etc. to decode the barcode.

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 a conceptual diagram of the scanning window of the intra-window maximum level difference calculation circuit in the device, and FIG. 3 is a diagram showing the main parts of the device. FIG. 4, which is a conceptual diagram of the filled-in barcode area, is an operation flowchart for calculating the addresses of four points in the same barcode rectangular area. 2... Maximum level difference calculation circuit within the window, 4...
... area determination circuit, 8 ... slope/center calculation circuit, 9 ... address calculation circuit. Name of agent: Patent attorney Shigetaka Awano and one other person
lz Diagram (A) Main oligomerization direction X

Claims (2)

[Claims] (1) Intra-window maximum level difference calculating means for scanning the scan-resolved data of an original image including a rectangular barcode area with an m×n scanning window and calculating the difference between the maximum signal level and the minimum signal level of pixels within the scanning window. and a first binarization means for binarizing the difference using a fixed threshold value, an area determination means for enlarging the binarized output by a predetermined size and making the binarized outputs continuous, and the scanning decomposition data. a second binarization means for binarizing the data, a storage means for storing the binary data, a calculation means for computing the inclination and center of the rectangular barcode from the area determination data, and An image signal processing device comprising: address calculation means for reading data from a storage means; and barcode decoding means for decoding a barcode from the data read from the storage means. (2) Intra-window maximum level difference calculating means for scanning the scan-resolved data of the original image including the rectangular barcode area with an m×n scanning window and calculating the difference between the maximum signal level and minimum signal level of the pixels within the scanning window. and a first binarization means for binarizing the difference using a fixed threshold value, an area determination means for enlarging the binarized output by a predetermined size and making the binarized outputs continuous, and the scanning decomposition data. a second binarization means for binarizing the area determination data; a cutting means for gate-outputting the binary data using the area determination data; a storage means for storing the extraction data; calculation means for calculating the slope and center of the storage means; address calculation means for reading data from the storage means according to the direction of the slope; and barcode decoding means for decoding a barcode from the data read from the storage means. An image signal processing device included.