JPS6349897A - Image information processor - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an image information processing device that reads images of printed matter such as banknotes and processes the information in a banknote validator or the like.

('b) Summary of the Invention The image information processing device according to the present invention is used, for example, in a bill validating device that reads an image of a printed matter such as a bill, compares it with validation data, and identifies the authenticity of the bill.

This invention eliminates the effects of misalignment of the printing position on the paper, especially when performing image information processing on printed matter such as banknotes, which are printed only in the center and have a frame in the periphery where no image is formed. (C) Prior Art Conventionally, as an image identification method for printed matter with a frame, checking the outer shape of the printed matter and checking the image pattern have been performed. In image pattern checking, coordinates are generated based on the edge or center of the outer shape of the printed matter that has already been determined, the state of the image at a series of coordinate positions is detected, and the state of the image is compared with pre-stored template data for comparison. By comparison, the identification is comprehensively verified.

(d) Problems to be Solved by the Invention However, such conventional image identification methods for printed matter with a frame assume that the printing position remains constant without deviation from the outer edge of the printed matter. Therefore, if the printing position is shifted with respect to the paper, the read image pattern will obtain image pattern data at a shifted position, and there is a risk of erroneous recognition.

FIGS. 8(A) to 8(F) are diagrams showing examples of printing position deviations in framed printed matter.

FIG. 3A shows an ideal printing example in which a printed part (pqrs) is shaped in the center of a sheet of paper (PQR3). Here, if the width of the paper is A and B, and the width of the image of the printed part is A' and B', then the width al of the frame part other than the printed part of the paper is.

a2. bl and b2 each have the same width.

On the other hand, FIG. 2B shows a case where the printed portion is shifted in the longitudinal direction of the paper. Further, FIG. 2C shows a case where the printed portion is shifted in the width direction of the paper. The same figure (D
) represents a case where the printed part is deviated by a certain angle in the rotational direction with respect to the paper.

Furthermore, FIG. 3E shows a case where the outer shape of the paper itself is deformed.

As described above, even if the printed matter is the same, the relationship between the outer shape of the paper and the printed portion may be deviated in various ways. Figure (F) shows a case where the printed part is shifted in both the longitudinal direction and the width direction of the paper, but even if the data at the predetermined position N points of the printed image is read using the conventional method,
Actually, image data of M points will be read out.

The present invention solves these conventional problems, and aims to provide an image information processing device that enables accurate recognition even if the printing position on the paper is shifted.

FE1 Means for Solving Problems This invention comprises: an image sensor that reads an image of a printed matter; an image recognition means that performs image recognition by comparing an output signal of the image sensor with identification data stored in advance; An image information processing apparatus comprising: an image edge detection means for detecting an edge of a printed image from an output signal of the image sensor; and the image recognition means uses the image edge detected by the detection means as a reference. The feature is that it performs image recognition.

(f) Effect With the above configuration, the image edge detecting means detects the edge of the printed image from the output signal of the image sensor. The image recognition means performs image recognition based on the edge of the printed image detected by the image edge detection means. Therefore, even if the printed part is misaligned with respect to the paper, image recognition is performed based on the edge of the printed image, so
Accurate image recognition can be performed at all times.

(8) Embodiment FIG. 1 shows a block diagram of an image information processing apparatus according to an embodiment of the present invention.

The CPU 2 is a processing device that controls the entire control section, and its control program is written in the ROM 3 in advance. ROM4 is a memory that stores various data such as template data used for image recognition, RAM5 stores images of printed matter read by an image sensor,
It is also a memory used as a working area for other image processing.

The I10 boat 6 is an input/output port to which the printing end detection device 1 and the A/D converter 7 are connected.

The image sensor 9 reads the image of the printed matter and outputs an image signal. The controller 8 is a controller for the image sensor 9 and provides a read clock pulse to the image sensor 9 and outputs the read image signal to the A/D converter 7. The A/D converter 7 converts the image signal into digital data and outputs it to the I10 port 6.

The print edge detection device 1 is a device that detects the edge of the printed portion relative to the paper based on the image data once read into the RAM 5, and detects any deviation thereof.

FIG. 2 is a flowchart showing the processing procedure of the control section.

First, the CPU reads the output signal of the image sensor,
It is determined whether the printed matter has arrived at the position of the image sensor (nl). When the printed matter reaches the position of the image sensor, the output of the image sensor is read from the A/D converter and stored at an address corresponding to the scanning timing (n2). This process is repeated until the printed material passes the image sensor (n3→n2). After all the image data of the printed matter is stored in the memory, the image data is sequentially read out from the memory, and the print edge detection device 1 (PE
D) (n4). The printing edge detection device 1 is a device that receives image data and calculates printing deviation data from the image data, as will be described later, and reads the printing deviation amount data output from the printing edge detection device 1 ( n5
).

Based on this data, the already stored image data is rearranged (n6). For example, if the printed part is misaligned parallel to the paper, this process shifts the image data based on the data representing the amount of misalignment in the X direction and the amount of misalignment in the Y direction to find the ideal printing position. Correct the image data to be the same as when reading the printed matter.

Thereafter, the authenticity of the printed matter is determined (nl). The authenticity of a printed matter is determined by comparing a pattern at a specific position on the printed part with template data, and the position to be compared is determined using the edge of the printed part as a coordinate axis or the center line of the printed part as a coordinate axis. For example, in FIG. 5(A), point Sl of the printing section
, S2 represents an example in which the coordinates are determined with O being the upper left end of the printing section. Further, in FIG. 5(B), the center of the printed area is set to 0, and the point S3. S4. This shows an example in which the coordinates of S5 are determined.

If the comparison results in a match, a matching process is performed and the process ends (n8). If there is a mismatch, the template data is switched to the next template data to be compared and the determination is made (n10→n?). If there is no match in the comparison with all template data, a match process is performed and the process ends (nil).

FIG. 3 is a flowchart showing the processing procedure of the print edge detection device 1.

First, when data is output from the CPU 2 via the I10 boat 6, this data is read and stored (n2
0→n21). This data is used in step n in FIG.
This is the image data output in step 4.

If all the data is manually processed, the stored image data can be searched for multiple lines of data in the X and Y directions, respectively.
The edge of the printing section is detected (n23).

FIG. 4 is a diagram illustrating the operation of detecting the end of the printing section. The outer shape of the printed matter represents an area corresponding to the image data stored in the memory, and among the contents of this memory, image data corresponding to the X-direction sampling line is sequentially read out,
The positions of the ends P3 and P4 of the printing section are detected. This can be detected because the frame portion of the printed matter is not printed and has a higher brightness than the printed portion. Also, Y
Regarding the direction, the ends Pi and P2 of the printing section are detected for the two sampling lines. The amount of rotational deviation, the amount of deviation in the X direction, and the amount of deviation in the Y direction of the printing unit are detected from the edges P1 to P4 detected in this way (n2
4). Furthermore, these deviation data are output (n25
). The deviation data thus output is read by the CPU at step n5 shown in FIG.

In the above embodiment, the image data of the printed matter read by the image sensor is stored in the memory and then subjected to image processing, but it is possible to correct the misalignment of the printed part at the stage of reading the image signal from the image sensor. . Next, an example will be explained.

FIG. 6 is a diagram showing the relationship between the printing state of printed matter and the output of the image sensor. As shown in the figure, when an image sensor reads an image for one scanning line of a printed matter, the output of the image sensor is at the maximum level in the frame area of the printed matter, and the output of the image sensor is at the maximum level in the frame area of the printed matter, and the output of the image sensor varies depending on the shading as shown at point X, for example. A new level will appear. Therefore, by setting the threshold level near the white level, the image data reading reference pulse signal can be obtained from the output signal of the image sensor. By not storing the A/D conversion result of the image sensor output in the memory based on this reference pulse, image data can be stored from the end of the printing section. Although the figure shows the horizontal direction, image data can be stored in the vertical direction as well from the edge of the print section. In this way, the influence of printing misalignment can be removed.

FIG. 7 is a flowchart showing the processing procedure in such an image information processing apparatus. First, it is determined whether the printed matter has arrived at the position of the image sensor (n30). When the printed matter arrives, the image sensor starts scanning and detects the print edge (n31→n32). If the print edge is detected, image data is read from that position and stored (n33). If storage is performed up to the rear end of the printing section in one scanning line, wait for the timing of the next line scan and repeat the same process (n34→n35→n36→
n31). During this repetition, if the printed matter passes, it is determined whether the stored image data matches the template data and the authenticity of the printed matter is determined (n37).

(h) Effects of the Invention As described above, according to the present invention, when performing image information processing on a printed matter whose printing position is shifted, the edge of the printed image is detected and the image data is adjusted based on this edge. Since the position of each point is determined, it is possible to eliminate the influence of misalignment of the printing position.

This makes it possible to perform accurate image recognition.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a control section of an image information processing apparatus according to an embodiment of the invention, FIG. 2 is a flowchart showing the processing procedure of the ipsilateral 'pl [1 part], and FIG. A flowchart showing the processing procedure of the print edge detection device, FIG. 4 is a diagram for explaining the detection operation of the print edge detection device, and FIGS. 5(A) and (B) explain the reference position for image recognition. FIG. 6 is a diagram for explaining the operation of an image information processing apparatus according to another embodiment of the present invention, and is a diagram showing the relationship between printed matter and image sensor output, etc.
FIG. 7 is a flowchart showing a processing procedure of an image information processing apparatus according to another embodiment, and FIGS. 8(A) to 8(F) are diagrams showing examples of printing position deviations in a printed matter with a frame.

Claims (1)

[Claims] (1) An image information processing device comprising an image sensor that reads an image of a printed matter, and an image recognition means that performs image recognition by comparing an output signal of the image sensor with pre-stored identification data, Image edge detection means for detecting the edge of a printed image from an output signal of an image sensor is provided, and the image recognition means performs image recognition based on the image edge detected by the detection means. Characteristic image information processing device.