JP2924896B1 - Picture postcard judgment method and picture postcard judgment apparatus - Google Patents

Abstract

A postcard determination method and a postcard determination device capable of performing high-speed and high-precision determination while suppressing an increase in cost. SOLUTION: One or more line segments extending in a lateral direction in an image of a postal matter to be processed are detected using an image scanning device.
Next, the total length of the line drawn on only the right half of the mail to be processed is calculated. Next, the total length is compared with a predetermined value. Then, when the total length is larger than the predetermined value, it is determined that the postal matter to be processed is a postcard.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a picture postcard judging method and a picture postcard judging method for judging whether or not a mail to be processed is a postcard, and more particularly to a picture postcard judging method capable of making a judgment with high speed and high accuracy. The present invention relates to a postcard determination device.

[0002]

2. Description of the Related Art An address area detecting device provided in a mail address automatic reading / sorting machine detects an address area in which an address of a postal matter such as a postcard, an official postcard, and a sealed letter is described. For a description of the configuration and operation of the mail address automatic reading / sorting machine, see Toshio Ishikawa et al., "Postal mail address automatic reading / sorting machine for Japan Ministry of Posts and Telecommunications (NEC Technical Report, Vol. 44, No.
3, pp. 25-30, 1991.3) ”. Also,
For a description of the configuration and operation of the address area detection device, see T.Ishika
Address Block Location and Format Iden by wa et al.
tification of Japanese Address Reading / Letter Sort
ing Machine (NECResearch & Development, Vol. 33, N
o. 2, pp. 217-225, April 1992) ”. In general, the address area of a postcard differs from that of an ordinary government-made postcard, so if it is possible to obtain information that determines whether or not the mail to be processed is a postcard, the overall detection accuracy and processing speed will be reduced. The effect of improving is obtained.

Therefore, a postcard detecting device for detecting whether a conveyed postcard is a postcard has been proposed (JP-A-56-51274). The conventional postcard detection device described in this publication includes a light source that irradiates light to the postcard to be detected, a first light receiving unit that receives specularly reflected light from the postcard to be detected, and irregularly reflected light from the postcard to be detected. And a comparison circuit for comparing the intensity of the specularly reflected light and the irregularly reflected light received by the first light receiving unit or the second light receiving unit. Then, it is determined whether or not the detected postcard is a picture postcard based on the comparison result by the comparison circuit.

[0004]

However, the detection device described in the above-mentioned publication requires the provision of a dedicated light source and a light receiving unit, and has a problem that the size of the device is increased and the cost is increased. In addition, there is also a problem that determination of whether or not it is a postcard is not correctly performed in many cases. Furthermore, the detection speed is not sufficient.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a picture postcard judging method and a picture postcard judging apparatus capable of performing high-speed and high-accuracy judgment while suppressing an increase in cost. And

[0006]

According to the present invention, there is provided a method for judging a postcard, the method comprising the steps of:
A step of detecting more than one line segment using an image scanning device; a step of calculating the total length of only the right half of the mail to be processed from the line segments; Comparing the postal matter to be processed as a postcard if the total length is greater than the predetermined value.

The step of calculating the total length includes the step of obtaining the left end position of all the line segments, and the step of processing the line segment whose left end position is in the right half of the mail to be processed among the line segments. The method may include a step of determining that the line is located in the right half of the target mail, and a step of calculating the sum of the lengths of all the line segments determined to be in the right half.

[0008] The step of detecting the line segment includes a step of generating a histogram indicating a distribution of black pixels in the image, a step of detecting a peak of the histogram, and a step of detecting a peak and a width of the peak. Determining whether there is a line segment extending in the horizontal direction at the position indicating the peak.

A picture postcard determining apparatus according to the present invention comprises: an image scanning device for reading an image of a postal object to be processed to create image data; and an image scanning device extending from the image data in a lateral direction in the image of the postal object to be processed. Line segment detecting means for detecting more than one line segment, and calculating the total length of the line drawn on only the right half of the mail to be processed from among the line segments detected by the line segment detecting means. Is compared with a predetermined value, and when the total length is larger than the predetermined value, a line segment length comparing means for judging that the postal matter to be processed is a postcard is provided.

[0010] The line segment may be an underline for address writing.

In the present invention, the image of the postal matter to be processed is read by the image scanning device to create image data. Then, one or more line segments extending in the horizontal direction in the image of the mail to be processed are detected, and it is determined whether or not the mail to be processed is a postcard based on the position and length of the line. You. At this time, since the sum of the lengths of only the line segments in the right half of the mail to be processed is calculated, the line segments drawn in the left half, which is a normal text region, are not to be processed. Therefore, it is possible to determine whether a picture is a postcard at high speed and with high accuracy.

The line segment referred to here is a discontinuous linear shape that becomes a continuous line segment by interpolating a blank portion on the line such as a broken line, a dotted line, a one-dot chain line and a two-dot chain line. It also includes finite lines.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION As a result of intensive experiments and research conducted by the present inventors in order to solve the above-mentioned problems, an address area of a postcard is usually provided in the right half of the address area. Are drawn, and it has been found that by detecting this line segment and using its length as a reference, it is possible to determine at high speed and high accuracy whether or not a postcard is a postcard.

Hereinafter, an apparatus for determining a postcard according to an embodiment of the present invention will be specifically described with reference to the accompanying drawings. FIG. 1 is a block diagram showing a picture postcard determining apparatus according to an embodiment of the present invention.

In this embodiment, there is provided an image scanner 1 which reads an image of a postal matter to be processed which is to be judged as a picture postcard and creates input image data. Further, an image memory 2 for storing input image data created by the image scanner 1 is connected to the image scanner 1. Further, a computer 3 is connected to the image memory 2. In the computer 3, a line segment detecting section 3a for detecting a line segment extending in the horizontal direction such as an underline in the input image data and the total length of the line segment detected by the line segment detecting section 3a are processed (processed). Target mail width) ×
A line segment length comparison unit 3b for comparing with 0.8 is provided.

A more detailed description of the configuration, operation, and the like of the image scanner 1 and the image memory 2 can be found in "New OCR Engine Architecture (NEC Research &
Development, Vol. 35, No. 1, pp. 80-88, January 19
94) ". The computer 3 is described in the above document except for the description of the line segment detection unit and the line segment length comparison unit.

Further, as described above, the line segment detector 3a
A line segment extending in the horizontal direction of the postal object to be processed, such as an underline, is detected.
A blank portion on the line such as a dotted line, a one-dot chain line, and a two-dot chain line includes a discontinuous linear finite line which becomes a continuous line segment when interpolated in black, for example.

Here, the operation of the line segment detector 3a will be described.
Further explanation will be given. The line segment detection unit 3a performs, for example, interpolation on the input image data while performing interpolation in the horizontal direction of the mail to be processed.
Create a histogram showing the distribution of black pixels. Thus, not only a line segment but also a discontinuous linear finite line such as a broken line is detected as a set of continuous black pixels. Next, a peak in the histogram is detected, and it is determined from the width and height whether or not a line segment exists at a position indicating the peak. Then, line segment detection result data is created from this result.

FIG. 2 is a schematic diagram showing an example of line segment detection result data. Although characters such as an address and text are drawn in a complicated manner on the postal object to be processed, the line segment detection result data obtained by the line segment detection unit 3a has the peaks in the histogram as shown in FIG. Since only the line segment determined from the width and the height is shown, it is extremely simplified.

Next, the operation of the picture-postcard judging device of the embodiment constructed as described above will be described. FIG. 3 is a schematic diagram showing an example of a postal object to be processed. As shown in FIG.
Usually, the address area of a postcard is provided in the right half thereof, and a line extending in the horizontal direction is drawn there.

FIG. 4 is a flow chart showing the operation of the picture postcard judging device of this embodiment. First, the image scanner 1 reads an image of a mail 4 to be processed and creates input image data (step S1).

Next, the image memory 2 stores the input image data (step S2).

Thereafter, the line segment detector 3a detects a line segment from the input image data stored in the image memory 2. Then, the line segment detection unit 3a creates line segment detection result data and outputs it (step S3).

Then, the line segment detection result data is input to the line segment length comparing section 3b. In the line length comparison unit 3b,
First, from the line segment detection result data, the number N of line segments and the coordinates (XL (I), XY (I), Y (I)) (I
= 1, 2, 3,..., N). In addition,
The origin of these coordinates is the lower left corner of the mail to be processed. FIG.
FIG. 3 is a schematic diagram showing a method of setting coordinates. As shown in FIG. 5, the vertical coordinate of the postal matter to be processed is Y.
(I), the leftmost coordinate in the horizontal direction is XL (I), and the rightmost coordinate is XR (I). Next, using the digitized data, the total length of the line segment detected by the line segment detection unit 3a is calculated, and it is determined whether or not the postal matter to be processed is a postcard, and this is output as determination result data. (Step S4).

FIG. 6 is a flow chart showing the judgment process of the line segment length comparing section 3b.

In the determination step of the line segment length comparing section 3b, first, the evaluation value R is initialized to 0 (step S11).

Next, the variable I is initialized with 1 (step S12).

Next, it is determined whether or not XL (I) is larger than (width of mail to be processed) / 2 (step S1).
3). Thereby, the coordinates (XL (I), XY (I), Y
It is determined whether or not the left end of the line segment indicated by (I)) is on the right side of the horizontal center of the mail to be processed. this is,
As mentioned above, the lines drawn on a postcard are usually
Since the line segment is located on the right half thereof, the line segment whose left end is not on the right side of the horizontal center of the mail to be processed is not to be distinguished from the line segment drawn in the address area unique to the postcard.

As a result of this determination, when XL (I) is larger than (width of postal matter to be processed) / 2, the evaluation value R is set to (XR
(I) -XR (I)) is added (step S14).

Thereafter, 1 is added to the variable I (step S
15). Note that as a result of the determination in step S13, XL
If (I) is not larger than (width of mail to be processed) / 2, 1 is added to variable I without adding (XR (I) -XR (I)) to evaluation value R (step S15). ).

Next, it is determined whether or not the variable I is greater than the number N of line segments (step S16).

If the result of this determination is that the variable I is not greater than the number N of line segments, the flow returns to step S13. On the other hand, as a result of the determination in step S16, if the variable I is larger than the number N of line segments, that is, if the calculation for all the line segments detected by the line segment detection unit is completed, the evaluation value R becomes It is determined whether or not it is larger than (width) × 0.8 (step S17).

As a result of this determination, when the evaluation value R is larger than (width of postal matter to be processed) × 0.8, it is determined that the postal matter to be processed is a postcard (step S18). on the other hand,
If the evaluation value R is not greater than (width of postal matter to be processed) × 0.8, it is determined that the postal matter to be processed is not a postcard (step S19).

As described above, in this embodiment, the line segment provided on the left half of the postal matter peculiar to the postcard and in which the text is described is excluded from the detection of the address area. For this reason, it is possible to prevent the area where the text is described from being erroneously detected as the destination area. That is, the detection accuracy is improved. Further, since no extra processing time is spent analyzing the area in which the text is described, the detection speed of the destination area is improved.

In this embodiment, the postal matter to be processed is determined to be a postcard if the total length of the line segment is larger than (width of postal matter to be processed) × 0.8. When the width is equal to or more than (the width of the target mail) × 0.8, the mail to be processed may be determined to be a postcard. Further, the value to be compared with the total length is not limited to (width of postal matter to be processed) × 0.8, but may be a value other than the width of postal matter to be processed, or a value to be multiplied by the value. May be set to a value other than 0.8.

[0036]

As described in detail above, according to the present invention,
It is possible to prevent the text area in which the text is described from being erroneously detected as the destination area, and it is possible to improve the detection accuracy. In addition, since it is not necessary to spend extra processing time on the analysis of the text area, the detection speed of the destination area can be improved. Further, since a dedicated light source and a light receiving unit are not required, an increase in cost can be suppressed.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a picture postcard determination device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram illustrating an example of line segment detection result data.

FIG. 3 is a schematic diagram showing an example of a postal object to be processed.

FIG. 4 is a flowchart illustrating the operation of the picture postcard determination device according to the present embodiment.

FIG. 5 is a schematic diagram showing a method for setting coordinates.

FIG. 6 is a flowchart illustrating a determination process of a line segment length comparison unit 3b.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1; Image scanner 2; Image memory 3; Computer 3a; Line segment detection part 3b; Line segment length comparison part

Claims (6)

(57) [Claims] 1. A step of detecting one or more line segments extending in a horizontal direction in an image of a postal object to be processed by using an image scanning device, and a right half of the postal item to be processed out of the line segments. Calculating the total length of only those drawn only, comparing the total length with a predetermined value, and determining that the mail to be processed is a postcard if the total length is greater than the predetermined value. A method for determining a postcard, comprising: 2. The step of calculating the total length includes obtaining a position of a left end of all the line segments, and determining a position of the left end of the line segments in a right half of the mail to be processed. A step of determining that the mail is in the right half of the mail to be processed;
Calculating the sum of the lengths of all the line segments determined to be in the right half. The method according to claim 1, further comprising the steps of: 3. The step of detecting a line segment includes the steps of: creating a histogram indicating a distribution of black pixels in the image;
Detecting a peak of the histogram, and determining whether there is a line segment extending in the horizontal direction at a position indicating the peak based on the height and width of the peak. The method for determining a postcard according to claim 1. 4. The method according to claim 1, wherein the line segment is an underline for address writing. 5. An image scanning apparatus for reading an image of a postal object to be processed and generating image data, and detecting one or more line segments extending in a lateral direction in the image of the postal object to be processed from the image data. And calculating the total length of a line drawn only in the right half of the mail to be processed from among the line segments detected by the line segment detecting unit, and comparing the total length with a predetermined value. A postcard determining apparatus comprising: a line segment length comparing unit that determines that the postal matter to be processed is a postcard when the total length is larger than the predetermined value. 6. The postcard judging device according to claim 5, wherein the line segment is an underline for address writing.