JPH0983740A - Template for character location designation and original reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the location of the image formed on an original, regardless of the presence or absence of a ruled line and a document, to obtain original reader provided with a means which is capable of correcting a layout in a short time and to facilitate the correction of the positional deviation and inclination of an original image. SOLUTION: This device has an auxiliary label detection means 3, a layout correction amount calculation means 4, an auxiliary label elimination means 5 and a layout correction means 6. By using the template of a transparent body having an auxiliary line and a hole for auxiliary lablel plotting, an auxiliary label designating a layout correction is drawn on an original, the auxiliary label is detected at the time of a reading, the location is determined and layout correction amount is calculated from the location of the auxiliary label. Next, as for the image data obtained by the reading of an original, the auxiliary label is eliminated and the positioinal deviation and inclination of an image are adjusted by using the calculated layout correction amount.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document reading apparatus including layout position detecting means and layout position correcting means for images such as character lines, drawings and photographs formed on a document.

[0002]

2. Description of the Related Art A document reading apparatus used in various document copying apparatuses or the like places a target document on a light-transmitting document table made of glass or the like and fixes it with a document cover to perform a reading operation. Be seen. Depending on the model, when reading the original, grasp the position and shape of the original on the original table,
Some also automatically set the copy size and correct the misalignment of the original.

As an original reading apparatus capable of correcting the deviation of the original placed on the original table, Japanese Patent Laid-Open No. 59-59-
The copying machine 102255 and the image reading apparatus disclosed in JP-A-5-276337 can be cited.

The copying machine described in Japanese Patent Application Laid-Open No. 59-102255 is provided with two sensor detection plates on a mirror support member which moves in a fixed direction to perform scanning, and two sensor detection plates are provided on the body frame of the copying machine. It has two sensors that match the plate. At the time of scanning, one sensor slides in the scanning direction, so a shift corresponding to the position of the document occurs at the time when it coincides with the sensor detection plate. Therefore, the start timing of the register roller is adjusted to shift the document. It is something to fix.

The image reading apparatus described in Japanese Patent Application Laid-Open No. 5-276337 obtains the pixel area, the center of gravity, and the inclination of the original for the image data obtained by scanning the original, and automatically sets the copy size and the center of gravity. The coordinate conversion formula is determined from the inclination and the inclination, the image data is processed, and the deviation of the document is corrected.

Not only correcting the deviation of the original placed on the original table, but also making a certain layout correction for images (hereinafter referred to as document images) such as character lines, drawings, and photographs formed on the original. As a document reading apparatus capable of performing the document reading, Japanese Patent Laid-Open Nos. 5-328096 and 5-32809
7 and the image processing device disclosed in JP-A-6-52309.

Japanese Unexamined Patent Publication No. 5-328096 and Japanese Unexamined Patent Publication No. 5-32
The copying machine described in 8097 takes out a text line from pixel data obtained by scanning a document on which a document image is formed, cuts out a space between each line, determines the direction of the text line, and determines the document line direction. It arranges the direction and rearranges the text lines.

The image processing apparatus described in Japanese Patent Laid-Open No. 6-52309 extracts a black line corresponding to a ruled line from pixel data obtained by scanning a document on which a document image having a ruled line is formed, and uses the least squares method. Is used to adjust the orientation of the document and remove the black line.

The conventional document reading apparatus as described above can correct the misalignment of the original or the misalignment of the document image by grasping the size and shape of the original, and therefore the copying machine. And a document filing system are used to simplify the work of manuscript reading and to enable layout editing to arrange the position of a document image.

[0010]

As described above, the conventional document reading apparatus not only corrects the misalignment of the document at the time of reading, but also corrects the document on the document placed on the document table. It is possible to correct the layout position of the image.

However, as described in JP-A-59-102255 and JP-A-5-276337, many document reading devices can correct the deviation of the document placed on the document table, but on the document. It is not possible to correct the deviation of the image that is tilted or unevenly distributed.

On the other hand, JP-A-5-328096 and JP-A-5-328096.
-328097, as disclosed in Japanese Patent Laid-Open No. 6-52309,
Some document reading devices not only correct the deviation of the document placed on the document table, but also correct the layout position of the document image formed on the document. However, JP-A-5-328096 and JP-A-5-32809
Since 7 is for correcting by cutting out between the lines of the document image, the layout position cannot be corrected for the document image consisting only of figures / photos.

Further, in Japanese Unexamined Patent Publication No. 6-52309, since lines are cut out with ruled lines and correction is performed, the layout position of a document image without ruled lines cannot be corrected. If the original has ruled lines, the position can be corrected without including the document image, but since the correction is performed by calculating the inclination of the black line in the image, the original contains black lines other than the ruled lines. If it does, there is a risk of causing an incorrect correction.

In any case, changing the layout position of the document image involves complicated processing for analyzing the read original image data. There is also a problem that an expensive large-capacity image memory is required because the data of the entire image is stored.

According to the present invention, the position of a document image formed on a document is detected regardless of the presence or absence of ruled lines or a document,
An object of the present invention is to obtain a document reading device equipped with a means capable of calculating a layout position correction amount in a short time, and to easily correct the positional deviation and inclination of a document image.

[0016]

In order to solve the above problems, according to the present invention, an auxiliary line is used in a document reading apparatus for detecting the inclination and position of a document image formed on a document and correcting the layout position. Using a template with holes for drawing auxiliary signs, a document with auxiliary signs for indicating the tilt and position of the document image on the paper is read, the auxiliary signs are detected, and their positions are determined and detected. The layout position correction amount is calculated from the difference between the position of the auxiliary sign and the reference position of the auxiliary sign. Next, with respect to the image data obtained by reading the original, the position and inclination of the image are adjusted by using the calculated layout position correction amount.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The template of the present invention is a grid-like auxiliary line for grasping the inclination and position of a document image on a document,
It has an auxiliary sign drawing hole for drawing an auxiliary sign on a document. Writing of the auxiliary marker is performed using the auxiliary marker drawing hole on the template in a state where the template is overlaid on the original and the position and inclination of the template are matched with the document image on the original. At this time, the inclination of the template is adjusted by making the auxiliary lines on the template parallel and / or perpendicular to each line, ruled line, and frame line of the figure. In addition, in order to easily align the top / bottom / left / right positions of the template with the document image,
It is advisable to provide auxiliary lines for measuring the left and right margins.

Not only the grid-like auxiliary lines, but also dots arranged at regular intervals, slits provided at regular intervals, and the like are conceivable instead of the auxiliary lines as long as the inclination and position of the document image can be grasped. . The shape of the auxiliary sign is not particularly limited, but in consideration of the fact that it is easy to draw using a template and that it is easy to detect when reading a document, a perfect circle,
Squares, crosses, etc. are preferred. Further, in order to handle originals of various sizes with one template, it is advisable to divide the area to be used by color or the like according to the size of the original, and to use the shape of the auxiliary marker properly.

In order to detect the auxiliary sign in the original image data obtained by reading the original, template matching for comparison with the standard shape of the auxiliary sign, or the auxiliary sign having a certain size and shape. The structural analysis method used can be used. Since the auxiliary signs are drawn using the template, there is a certain relationship between the relative position of each auxiliary sign and the distance between them. Therefore, the auxiliary sign detected at a position that does not satisfy this relationship can be determined to be a character or mark similar to the auxiliary sign. By utilizing this, even if a character or mark similar to the auxiliary sign is present in the document, highly reliable auxiliary sign detection that does not cause false detection is realized.

The layout position correction amount is calculated from the difference between the original position of the auxiliary mark that should be present in the original document that does not need to be corrected for layout position and that is not tilted or displaced, and the position of the auxiliary mark actually detected. . As a method of displaying the position of the auxiliary sign, for example, it is considered that the auxiliary mark position is represented by an XY coordinate system whose origin is the center of the document, and the layout position correction amount is corrected in each of the X direction and the Y direction in the coordinate system. It may be considered to be represented by a movement amount and a rotation correction angle around the origin.

If there are no restrictions on the layout position correction range, that is, the vertical position correction range, the left and right position correction range, and the tilt angle correction angle, the auxiliary mark is present anywhere on the document. Therefore, it is necessary to read the entire document. On the other hand, when a certain limit is set in the layout position correctable range, the area where the auxiliary marker exists on the original document is limited, and therefore the auxiliary marker can be detected without reading the entire original document. The image memory can be used to configure the device.

The original image data obtained by reading the original is subjected to layout position correction processing using the calculated layout position correction amount, and is output for copying, plate making, printing, displaying, etc. , Output image data).

The document reading apparatus of the present invention comprises a document image reading means, an image memory for storing image data obtained by the document image reading means, an auxiliary mark detecting means, a layout position correction amount calculating means, a layout position correcting means, It is configured to have means for outputting image data and is basically used together with a template having auxiliary lines and auxiliary marker drawing holes.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of a document reading apparatus of the present invention will be described below in detail with reference to the drawings. Here, a copying apparatus incorporating the document reading apparatus of the present invention will be described as an example. FIG. 1 is an explanatory diagram of a template used with the document reading apparatus of the present invention. 1A shows a document 11 and a template 12 on which a document image having an inclination and a positional deviation is formed. In order to explain the inclination and position of the document image in the figure, the image is shown by a plurality of ruled lines, but the present invention can be used for documents and originals of pictorial images regardless of the type of document image. The template 12 is a transparent body through which the document image below can be seen, and has an auxiliary sign drawing hole 13 for drawing an auxiliary sign. If there are at least two holes for drawing this auxiliary sign, the position and inclination of the document image can be designated.

However, only two auxiliary marker drawing holes 13 are provided.
If the template with is aligned with a document image having a large inclination or positional deviation, the auxiliary marker drawing hole 13 may be out of the document paper, and it may not be possible to draw two auxiliary markers. Therefore, it is necessary to provide a plurality of auxiliary marker drawing holes 13 on each side of the template in order to cope with a document having a large inclination or positional deviation.

For the purpose of facilitating the inclination of the template to match the inclination of the document image, auxiliary lines 17 are drawn on the template at equal intervals horizontally and vertically. Instead of the auxiliary line 17, it is also possible to use a grid point such as a dot or a cross at the intersection of the auxiliary lines. Further, a margin measuring auxiliary line 16 is provided on each side of the template for facilitating the alignment of the top and bottom / left and right margins. By aligning the top line / bottom line of the manuscript, or the left and right ends of each line with specific margin measuring auxiliary lines 16, the top and bottom margins can be specified precisely.

The inclination and positional deviation of the document image can be grasped by superposing the template 12 on the original 11 as shown in FIG. The template 12 is superposed on the original 11 with the inclination of the auxiliary line 17 matched with the inclination of the characters and chart of the document image and the document image being arranged at an appropriate position with respect to the auxiliary line 16 for margin measurement. By using the mark drawing hole 13, the auxiliary mark can be drawn at an appropriate position on the document.

The position of the auxiliary sign drawn at this time is
The position information and the tilt information of the document image are reflected. In this way, the position on the document where the auxiliary marker is written is determined by the position and the inclination of the document image. Therefore, by analyzing the position of the auxiliary marker in the captured image data, the document can be analyzed. The position and inclination of the image can be detected accurately. Although the auxiliary marker drawing hole 13 is circular in the figure, it may be a square or the like that is easy to draw, the detection and the position can be easily grasped, and the auxiliary marker is easily removed from the image data.

The document reading apparatus of the present invention reads the document on which the auxiliary mark is drawn, and then reads the original position of the auxiliary mark, which should originally exist for the document image which does not require layout correction. The layout position correction amount is obtained from the difference from the detected position of the auxiliary marker, the auxiliary marker image in the image data is removed, the layout position is corrected, and output image data is obtained. The copy printed matter 15 produced using the output image data has the image positional deviation and inclination corrected as shown in (3) of FIG.

FIG. 2 is a processing block diagram showing an example of the configuration of the document reading apparatus of the present invention. The figure shows a document reading apparatus of the present invention including a document image reading unit 1 and an image memory 2, an auxiliary mark detecting unit 3, a layout position correction amount calculating unit 4, an auxiliary mark removing unit 5, and a layout position correcting unit 6, and a copy. A copying apparatus in which the image printing means 7 is combined is shown. In this example, the reading of the original image is performed twice, that is, the prescan and the main scan, and the processing is performed according to the procedure shown by the arrow in the figure.

At the time of prescan, the original image reading means 1
~ The processing in the layout position correction amount calculation means 4 is sequentially performed. The original image is read by the original image reading means 1,
The obtained image data is stored in the image memory 2. The position of the auxiliary marker is detected from the image data stored in the image memory 2 by the auxiliary marker detecting means 3, and the normal position of the auxiliary marker at which the auxiliary marker for the document image which does not require layout correction should originally exist, The layout position correction amount calculation unit 4 calculates the layout position correction amount based on the difference from the detected position of the auxiliary marker.

If the layout position correction range is not limited, the auxiliary mark may exist anywhere on the document, and the entire document must be read. on the other hand,
When a certain limit is set in the layout position correctable range, the area where the auxiliary marker exists on the original document is limited, so that the auxiliary marker can be detected without reading the entire original document.

FIG. 3 is an explanatory view showing the existence range of the auxiliary marker on the original in the example of the original reading apparatus of the present invention when the range in which the layout position can be corrected is limited.
The auxiliary sign 14 is the normal position of the auxiliary sign attached to the document image having no inclination or misalignment. Here, the range in which the layout position can be corrected is ± Δx in the horizontal direction and ±± in the vertical direction.
When Δy is ± θ in the left and right rotation directions around the origin, the range in which the auxiliary marker on the document can exist is limited to the shaded area in the drawing. In the pre-scan, it is only necessary to read a part of the original so as to include the existence range of the auxiliary marker and take the data into the image memory 2, so that the system can be configured with a small capacity image memory.

During the main scan, the processes of the original image reading means 1, the auxiliary mark removing means 5 to the copy image printing means 7 are sequentially performed. The original image reading means 1 reads the entire original, and the image data obtained successively is sent to the auxiliary mark removing means 5. The auxiliary marker removing unit 5 removes the auxiliary marker from the image data based on the position of the auxiliary marker detected by the auxiliary marker detecting unit 3 during the prescan. The layout position correction unit 6 corrects the layout position of the image data based on the layout position correction amount sent from the layout position correction amount calculation unit 4. The corrected image data is sent to the copy image printing unit,
Obtain a copy print.

The auxiliary marker drawn on the original using the template is captured as image data and then detected by the auxiliary marker detecting means to obtain the center coordinates of the auxiliary marker as position information of the auxiliary marker. For the auxiliary mark detecting means, template matching, or a structural analysis method utilizing the fact that the mark is a circle or a square having a certain size can be used.

Since the auxiliary signs are drawn using the template, there is a certain relationship between the distance between the center coordinates of the auxiliary signs and their relative positions. Therefore, the auxiliary sign detected at a position that does not satisfy this relationship can be determined to be a character or mark similar to the auxiliary sign. By utilizing this, even if a character or mark similar to the auxiliary sign is present in the document, highly reliable auxiliary sign detection that does not cause false detection is realized.

The layout position correction amount calculation means 4 obtains the layout position correction amount as follows. Assuming that N auxiliary markers have been detected, their center coordinates are (x ₀ , y ₀ ), (x ₁ , y ₁ ), ..., (x _N-1 , y _N-1 ), respectively.

On the other hand, there is no displacement or inclination in the document image,
When the layout position correction is not required, the coordinates of the position where the above auxiliary sign should originally exist are (a ₀ , b ₀ ), (a ₁ , b ₁ ), ..., (a _N-1 , b _{N- 1} )

At this time, the angle A _ij formed by the straight line (x _i , y _i )-(x _j , y _j ) and the straight line (a _i , b _i )-(a _j , b _j ) is all i, The average value A obtained for the set of j (where i ≠ j) corresponds to the tilt angle of the document image.

[0040]

[Equation 1]

Therefore, by correcting the angle of the captured image data by the angle -A by the layout position correcting means 6, it is possible to correct the inclination of the document image which is printed while being inclined on the original. Further, the horizontal and vertical position correction amounts of the document image are obtained as follows. Center coordinates (rx ₀ , ry ₀ ), (rx ₁ , ry ₁ ), ..., (r) when the detected N auxiliary markers are rotated by the angle −A about the origin.
x _N-1 , ry _N-1 ) is calculated by the following equation.

[0042]

[Equation 2]

However, in the equation, i = 0, 1, ..., N-1. Then, the horizontal position correction amount ε _x and the vertical position correction amount ε _y can be obtained by the following equations.

[0044]

(Equation 3)

The processing up to this point is performed at the time of pre-scan, and thereafter, the original image is read again by the main scan, and the position is corrected according to the correction amount to generate a copy image.

The auxiliary mark removing means for removing the auxiliary mark from the original image captured by the main scan is for performing image processing so that the auxiliary mark is not printed on the copy printed matter. In one example, the position where the auxiliary sign is present is given from the auxiliary sign detecting means as the central coordinates of each auxiliary sign, and therefore, for example, it is possible to forcibly erase the image within a certain range of area centered on the coordinates. A means to remove the auxiliary marker can be considered.

The original image from which the auxiliary mark has been removed is further subjected to position correction in the tilt angle, horizontal direction, and vertical direction by the layout position correcting means 6 to obtain a copied image. The layout position correcting means 6 rearranges each pixel of the image data fetched from the original based on the inclination angle A and the position correction amounts εx and εy given from the layout position correction amount calculating means. The layout position is corrected by. The image data that has undergone the layout position correction is passed to the copy image printing means 7 as output image data to obtain a copy print.

[0048]

As described above, the document reading apparatus of the present invention is
It is possible to correct the layout position of the document image, such as the position shift or inclination of the document image on the document. The layout position correction amount is specified by drawing an auxiliary sign on the original. At this time, by using the template having the auxiliary line and the hole for drawing the auxiliary marker, the inclination and the position of the document image can be easily grasped and the auxiliary marker can be drawn at the correct position. Even if the original does not include any characters or ruled lines, it is possible to easily and appropriately correct the layout position by drawing the auxiliary mark and processing it by the original reading apparatus of the present invention.

Further, since the process of calculating the layout position correction amount is simple, the time required for the process can be shortened.
Furthermore, when a certain limit is set in the layout position correctable range, there is no need to store the data of the entire image, and there is an effect that it is not necessary to use an expensive large-capacity image memory.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a template used with a document reading apparatus of the present invention.

FIG. 2 is a processing block diagram showing an example of a configuration of a document reading apparatus of the present invention.

FIG. 3 is an explanatory diagram showing an existing range of an auxiliary marker on a document in an example of the document reading apparatus of the present invention.

[Explanation of symbols]

 1 Document Image Reading Means 2 Image Memory 3 Auxiliary Mark Detection Means 4 Layout Position Correction Amount Calculation Means 5 Auxiliary Mark Removal Means 6 Layout Position Correcting Means 7 Copy Image Printing Means 11 Originals 12 Templates 13 Auxiliary Mark Drawing Holes 14 Auxiliary Marks 15 Copy Printed material 16 Auxiliary line for margin measurement 17 Auxiliary line

Claims (2)

[Claims] 1. An auxiliary line for grasping a tilt or a position of a document image such as a character line, a drawing, or a photograph formed on a document, and an assist for designating the tilt or the position of the document image. A character position designating template having two or more auxiliary marker drawing holes for writing a marker on a document. 2. An auxiliary line for grasping a tilt or a position of a document image such as a character line, a drawing, or a photograph formed on a document, and an assist for designating the tilt or the position of the document image. A document image reading unit for reading a document image in which a supplementary mark is drawn by a template having two or more auxiliary mark drawing holes for writing a mark on a document, and image data obtained by the document image reading unit is stored. An image memory, an auxiliary mark detecting means for detecting the position of the auxiliary mark image in the image data, a tilt angle correction amount and a position correction amount required when correcting the layout position of the document image in the image data, Layout position correction amount calculation means for calculating from position information of the detected auxiliary sign, document in image data according to the layout position correction amount An original reading apparatus comprising: a layout position correcting unit that corrects a layout position of an image; and a unit that outputs image data after the layout position correction.