JP2001251492A - Device for correcting image information tilt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image information tilt correcting device for preventing the occurrence of distortion surpassing an allowed range. SOLUTION: This device has an inclination quantity detecting means (e.g. CPU 2) for detecting the tilt amount of image information, corrects the tilt of image information by moving pixel information horizontally and vertically in accordance with the tilt amount detected by the tilt amount detecting means when the image information is inputted in a tilted state. The device is provided with an allowable distortion quantity storing means (e.g. allowable distortion quantity setting part 16) for storing allowable distortion quantity and a correction deciding means (e.g. CPU 2) for deciding whether the tilt correction of the inputted image information is to be performed on the basis of the correlation between the tilt amount detected by the tilt amount detecting means and the allowable distortion quantity stored in the allowable distortion quantity storing means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image information inclination correcting device for correcting the inclination of image information read by a document input device such as a scanner.

[0002]

2. Description of the Related Art When image information is read by an image input device such as a scanner and displayed on a display or printed by a printing device, the obtained image information may be inclined.

For example, as shown in FIG. 10, when copying an original 21 by a copying machine, if the original 21 is copied without being aligned with the instruction guide 23 on the original platen, the image information 24 is read at an angle. The resulting duplicate image (copy 22) is also inclined. Further, even if the operator intends to place the original 21 on the original plate in accordance with the instruction guide 23, the original 21 may be displaced when the original cover is operated. The resulting duplicated image is tilted. Further, when the image information of the original 21 is inclined with respect to the periphery of the sheet, it is meaningless to align the original 21 with the instruction guide 23 of the original platen. Therefore, in reality, it is very difficult to obtain a copy document without inclination.

Conventionally, in order to solve such a problem, there has been proposed a method of once reading a document into a storage device, detecting a tilt amount, and correcting image information based on the detected tilt amount.

As shown in FIG. 11, specific inclination correction of image information is roughly performed in the following three steps. 1) Read image information. 2) The inclination of the read image information is detected. 3) The tilt of the image information is corrected based on the detected or input tilt amount.

A method for detecting the inclination of image information read by an image input device is disclosed in Japanese Patent Publication No. 63-25391, Japanese Patent Application Laid-Open No. 7-105310, and Japanese Patent Application Laid-Open No. 9-311.
907 and the like.

As a method of correcting the inclination of the image information based on the detected amount of inclination of the image information, a method using a conversion formula (A) shown in FIG. 12 is well known. This method of correcting the inclination of the image information is a method of obtaining the corrected positions x and y from the positions X and Y of the pixels of the original image information and the amount of inclination θ in the orthogonal coordinates. This method of correcting the inclination of the image information requires an enormous amount of processing time because the position after correction is obtained for each pixel using the above-described conversion formula (A).

A method for correcting the inclination of image information which is an alternative to the method requiring an enormous amount of processing time is disclosed in Japanese Patent Laid-Open No. 6-6824.
No. 5, JP-A-9-6914. This image information inclination correction method determines the division width,
The tilt of the image information is corrected by shifting the pixel in each of the divided areas in the horizontal direction and the vertical direction. That is, this image information inclination correction method uses a conversion equation (B) shown in FIG. 13 and a conversion equation (C) shown in FIG. 14 as a conversion equation instead of the conversion equation (A) used conventionally. . These conversion formulas can perform processing in units of regions, not in units of pixels, and thus have a feature that high-speed processing can be performed.

[0009]

However, as can be seen by comparing the conversion formulas (A), (B) and (C), they can be obtained by the conversion formulas (B) and (C). The coordinate values are multiplied by cos θ or divided by cos θ, which appears as distortion.

FIG. 15 shows distortions generated by the conversion equations (B) and (C). For example, suppose that a square having a side length of S1 or a circle having a diameter of S1 is input at an inclination of 26.5 degrees, and correction is performed in the vertical direction (y direction) and the horizontal direction (x direction) ( As shown in FIG. 13) and FIG. 15A, the rotation process is performed, but the shape after the rotation is distorted. That is, a square expands vertically and shrinks horizontally. This is the same for circles.

The horizontal direction (x direction) and the vertical direction (y
Even if the correction is performed in the order of (direction) (see FIG. 14), as shown in FIG. 15B, distortion occurs in both the square and the circle as described above. For measures against such distortion, see the above-mentioned Japanese Patent Application Laid-Open No. 6-68245.
Nothing is mentioned in Japanese Unexamined Patent Application Publication No. Hei 9-6914.

By the way, image information is composed of various elements such as characters, ruled lines, figures, photographs, etc. Distortion that occurs when these image information is input while being inclined and the inclination is corrected is as follows. Depending on the content of the image information, there are cases where it is allowed and cases where it is hardly allowed. For example, if the original image information is a design drawing, the allowable distortion range is small, but if the original image information is composed of only characters and ruled lines, the allowable distortion range is large. it is conceivable that.

The present invention has been proposed in view of the above-described circumstances, and obtains in advance a distortion amount generated when correcting the inclination of image information and compares the distortion amount with an allowable range of distortion amount. It is an object of the present invention to provide an image information inclination correction device for preventing generation of distortion exceeding a range to be corrected.

[0014]

The image information inclination correcting apparatus according to the present invention has the following features in order to achieve the above object.

The image information skew correction apparatus according to the present invention has a skew amount detecting means for detecting the skew amount of the image information. An image information inclination correcting apparatus for correcting the inclination of the image information by moving the pixel information in the horizontal and vertical directions according to the amount of the inclination, and an allowable distortion amount storing means for storing an allowable distortion amount; To determine whether or not to perform the inclination correction of the input image information based on the correlation between the inclination amount detected by the inclination amount detecting means and the allowable distortion amount stored in the allowable distortion amount storing means. And a correction judging means.

Incidentally, the above-mentioned Japanese Patent Application Laid-Open No.
In the image information skew correction method disclosed in Japanese Patent Application Laid-Open No. 9-6914, the skew of image information is corrected using the conversion formula (B) shown in FIG. 13 and the conversion formula (C) shown in FIG. However, if the cause of the distortion caused by the correction becomes clear, the degree of the distortion can be compared with the allowable distortion, and the subsequent processing can be selected.

That is, the image information inclination correcting apparatus according to the present invention executes the third step shown in FIG.
Alternatively, it is possible to take measures to interrupt the processing to correct the method of setting the original, and to prevent useless copying or the like.

Further, the image information inclination correcting apparatus according to the present invention provides a correlation between the inclination amount of the image information detected by the inclination amount detecting means and the allowable distortion amount stored in the allowable distortion amount storing means. The apparatus further includes an estimated distortion amount notifying unit for notifying the operator of the amount of distortion expected to occur at the time of correction based on the estimated distortion amount.

As described above, in the image information inclination correction apparatus according to the present invention, based on the correlation between the amount of distortion and the amount of inclination,
Deriving the amount of distortion from the amount of inclination, and if the amount of expected distortion exceeds the allowable range, suspends the processing and notifies the operator to that effect, such as in a document mainly composed of characters, etc. The operator can decide whether to ignore the distortion and continue processing as it is or to re-install the original to reduce the inclination as in the case of drawings, etc. Together with
Unnecessary duplication can be prevented from being created.

Further, the image information inclination correcting apparatus according to the present invention is provided with an allowable distortion amount input means for allowing an operator to set an allowable distortion amount to be stored in the allowable distortion amount storage means. Things. As described above, in the image information skew correction apparatus according to the present invention, by allowing the operator to set the allowable amount of distortion, selection according to the content of the document can be performed, thereby improving the work efficiency and reducing unnecessary copies. Can be prevented from being created.

Further, the image information inclination correcting apparatus according to the present invention is characterized in that the image information inclination correcting apparatus is provided with setting means for not performing inclination correction. Depending on the content of the original, there is a case where it is desired to output the original without correcting the inclination (for example, FIG.
As shown in FIG. 6, by making it possible to make settings that do not perform inclination correction, the operator can select whether or not correction processing is necessary, thereby further improving work efficiency. Can be.

In the image information inclination correcting apparatus according to the present invention, when the correction judging means judges that the inclination correction of the image information is not performed, the inclination amount of the image information detected by the inclination amount detecting means is determined. And a reset position information notifying unit for notifying the operator of numerical information on the reset position of the document derived from the document size of the image information.

As described above, in the image information inclination correcting apparatus according to the present invention, when a predetermined amount of distortion is exceeded, the operator is notified of how much to shift the predetermined portion of the placed document. Thereby, usability can be further improved. In particular, in a scanner or a copier, since the document surface is viewed from the back side, it is difficult to know which direction to shift and how much, for example,
By displaying "the lower right corner of the document is 18 mm below", a very easy-to-understand man-machine interface can be provided.

Further, the image information skew correction apparatus according to the present invention is characterized in that it has a distortion removing means for removing distortion of an image obtained by correcting the skew of image information. .

As described above, in the image information inclination correcting apparatus according to the present invention, the image distortion can be corrected by deriving the distortion amount from the inclination amount, and a good image can be obtained.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of an image information inclination correcting apparatus according to the present invention will be described with reference to the drawings.

<Specification of Distortion Amount> First, how to specify the distortion amount of the image information in the image information inclination correcting apparatus according to one embodiment of the present invention will be described. In the image information tilt correction apparatus according to one embodiment of the present invention, an image information tilt correction method disclosed in Japanese Patent Application Laid-Open Nos. 6-68245 and 9-6914 is used. Perform tilt correction. That is, the above-described image information inclination correction method combines vertical correction and horizontal correction, but the distortion method differs depending on which correction is performed first.

Here, the case where the vertical correction is performed first will be described. Figure 1 corrects the image vertically,
It is explanatory drawing which shows the case where it correct | amended in the horizontal direction after that. When correcting the image in the vertical direction, the correction is performed using the conversion formula (Ba) shown in FIG. When correcting the image in the horizontal direction, the correction is performed using the conversion formula (Bb) shown in FIG.

That is, in FIG.
Indicates an image input by being inclined by θ, and the parallelogram J
The QRM is obtained by correcting the rectangle ABCD in the vertical direction, and the rectangle PQRS is obtained by correcting the parallelogram JQRM in the horizontal direction. In this case, the position of the origin O may be anywhere. The shape of the parallelogram JQRM or the rectangle PQRS generated by the correction process is not affected by the position of the origin, and the shape is unchanged. In FIG. 1, the origin O is located at the intersection of the extension of the side BC and the extension of the line segment QR for easy understanding.

With the first vertical correction, points A, B,
C and D move to points J, Q, R and M. By the following horizontal correction, points J, Q, R, and M are changed to points P, Q,
Move to R and S (points Q and R do not move). Therefore, the side AD becomes the side PS, and the amount of distortion in the horizontal direction can be determined by calculating the ratio of these lengths. Similarly, by determining the ratio of the length of the side AB to the length of the side PQ, the amount of distortion in the vertical direction can be determined.

From the conversion equation (B) where X and Y are the coordinates of the original image, x and y are the coordinates after correction, and θ is the amount of inclination, x = (Xcos θ + Ysin θ) · cos θ y = (Ycos θ−Xsin θ) / cos θ Becomes

Using this conversion formula, what kind of distortion is generated is derived. To facilitate understanding, in a rectangular ABCD, AD = BC = a, AB =
DC = b, and the coordinates of each point are represented by adding suffixes x and y. The amount of distortion in the horizontal direction can be represented by the ratio of AD (= a) and the length of PS, and the amount of distortion in the vertical direction is
It can be expressed by the ratio of AB (= b) to the length of PQ.

The x and y coordinate values of the point P are as follows: Px = (Axcosθ + Aysinθ) · cosθ Py = (Aycosθ−Axsinθ) / cosθ

The x coordinate value of the point S is given by Sx = (Dxcosθ + Dysinθ) · cosθ.

On the other hand, since the coordinate value of the point D is Dx = Ax + acosθ Dy = Ay + asinθ, the length of the line segment PS is: PS = Sx−Px = (Dxcosθ + Dysinθ) · cosθ− (Axcosθ + Aysinθ) · cosθ = (Axcosθ + acos the ^{2 θ + Aysinθ + asin 2 θ} -Axcosθ-Aysinθ) · cosθ = a (cos 2 θ + sin 2 θ) · cosθ = acosθ.

Further, since the length of the line segment PQ is Qy = 0, it is the y coordinate value of the point P, and PQ = Py = (Aycos θ−Axsin θ) / cos θ.

On the other hand, since the coordinate value of the point B is Bx = Ax + bsinθ By = Ay−bcosθ, the length of the line segment PQ is PQ = Py = ((By + bcosθ) cosθ− (Bx−bsinθ) sinθ) / cosθ = (Bycosθ−Bxsinθ + b) / cosθ = b / cosθ (∵Bycosθ = Bxsinθ) That is, the line segment AD (= a) becomes acos θ, which is reduced by (1−cos θ) × 100%.

The line segment AB is (1 / cos θ-1)
× 100%. Here, when the allowable distortion amount in the horizontal direction is α% and the allowable distortion amount in the vertical direction is β%,
Only when the following relationship is established between these values and the amount of inclination θ, the inclination correction processing of the original image information is performed, and if not, no correction is performed.

Α ≧ (1-cos θ) × 100 β ≧ (1 / cos θ−1) × 100 Hereinafter, this relational expression is defined as a judgment formula (1). Note that, as described above, α and β can be set separately, but α = β and the same value may be used.

Also, by changing the order of correction, the horizontal direction,
The amount of distortion when moving in the vertical direction is as follows. α ≧ (1 / cosθ−1) × 100 β ≧ (1-cosθ) × 100

<Image Information Tilt Correction Apparatus> A specific configuration of an image information tilt correction apparatus according to an embodiment of the present invention will be described. FIG. 2 is a block diagram showing a specific configuration of the image information tilt correction apparatus according to one embodiment of the present invention.

As shown in FIG. 2, an image information inclination correcting apparatus 1 according to an embodiment of the present invention includes a CPU (unit) 2, an operation unit 3, an original reading unit 4, an image display or image printing unit 5,
Document size detection unit 6, display unit 7, pixel information storage unit 8, processing storage unit 9, vertical correction control unit 10, horizontal correction control unit 11, horizontal correction unit 12, vertical correction unit 13 is a main component.

Incidentally, the image information inclination correcting device 1 shown in FIG.
Then, the allowable distortion amount setting unit 16 and the horizontal correction unit 12
And a vertical correction unit 13 are illustrated at the same time, but when a distorted image is generated, a horizontal correction unit 12 and a vertical correction unit 13 for correcting the distortion are provided. Does not require the allowable distortion amount setting unit 16. Note that the CPU 2 and its peripheral devices function as a tilt amount detecting unit and a correction determining unit.

<Operation Unit> The operation unit 3 includes a key unit 14 having keys for performing various settings and a key for instructing reading of an image. Tilt correction required / unnecessary setting unit 15 for selecting whether to correct the tilt or to output as it is without correction
And an allowable distortion amount setting unit for setting an allowable distortion amount for the image when the inclination is corrected.
The tilt correction necessity / unnecessary setting unit 15 and the allowable distortion amount setting unit 16 are composed of operation keys, like the keys constituting the key unit 14. When the image whose inclination has been corrected is subjected to image expansion / compression processing (STEP 7 in FIG. 9 described later), the allowable distortion amount setting unit 16 is not required. The operation unit 3 functions as an allowable distortion amount input unit.

<Document Reading Unit> The document reading unit 4 reads an image on a document based on a signal from the CPU 2, processes the image if necessary, and transfers it to the image storage unit.

<Image Display or Image Printing Unit> The image display or image printing unit 5 displays or prints information stored in the pixel information storage unit 8 based on a signal from the CPU 2.

<Document Size Detector> The above-described document size detector 6 detects the size of the placed document. In normal cases, it is difficult to detect the size of a document placed obliquely, but if the amount of tilt is small, the determination is made with a threshold, so that the determination can be made almost correctly. The length (L) of the lower side shown in FIG. 3 is obtained from the amount of tilt (θ), the size of the document, the placement (vertical or horizontal), and the like.
Calculate θ.

<Display Unit> The display unit 7 displays, for example, a message “Please lower the right end by xx (= Lsin θ)” when the detected tilt amount is larger than the allowable distortion amount. When the inclination is in the opposite direction to the case shown in FIG. 3, it is only necessary to change “lower” to “raise” and display Lsin θ as an absolute value.

In the example shown in FIG. 3, the image is not tilted, but the document 21 is tilted. Actually, as shown in FIG. 4A, the original 21 was correctly set, but the image may be inclined. In such a case, the message "Match the document to the guide ..." is not valid, and as described above, "the right end is xx (=
Lsinθ) "is effective. The operator who has received such an instruction is shown in FIG.
As shown in (b), the original 21 is rotated to correct the inclination of the image. However, in this case, as shown in FIG. 4C, there is a possibility that a part of the information of the document 21 is lost and an area where nothing is printed may be formed. The display unit 7 functions as an assumed distortion amount informing unit and a re-installation position information informing unit.

<Pixel Information Storage Unit> The above-described pixel information storage unit 8 stores the read image information. Also, CP
By interlocking with the processing storage unit 9 based on the signal of U2, the vertical correction control unit 10, the horizontal correction control unit 11, the vertical correction unit 13, and the horizontal correction unit,
Perform vertical / horizontal correction and vertical / horizontal correction.
The image information storage unit 8 functions as an allowable distortion amount storage unit.

<Processing Storage Unit> The processing storage unit 9 described above.
Temporarily holds data when processing image information stored in the pixel information storage unit 8 (vertical / horizontal correction, vertical / horizontal correction, etc.). That is, CP
Based on the signal of U2, data necessary for various processes is stored.

<Vertical Correction Control Unit> The vertical correction control unit 10 described above calculates the tilt amount θ by the CPU 2 and determines that the generated distortion amount is equal to or less than the allowable distortion amount. Is performed. FIG. 5 shows a method of vertical correction. FIG. 5A shows a state before correction, and FIG.
(B) shows a state after the vertical correction processing.

Although the origin in the vertical correction process may be anywhere, as shown in FIG. 6, if the x-coordinate values of the pixels are all positive, the directions in which the pixels move are all the same.
For the correction in the vertical direction, a conversion formula (Ba) shown in FIG. 13 is used. That is, the position of each pixel does not change the x coordinate (X = x ′), and moves only the y coordinate from the original position by Xtanθ in the negative direction of the y axis.

On the other hand, the number of moving dots is an integer, and Xta
nθ is rounded. As a result, the pixels included in the area (circle 3) shown in FIG.
The pixels included in the area (circle 4) are moved, for example, by four dots. That is, the pixels in the area (circle 3)
Pixels in all three dots and in the area (circle 4) may be moved by four dots. When such processing is performed, the state shown in FIG.

Here, the rectangular ABCD shown in FIG.
Corresponds to the parallelogram PQRS shown in FIG.
In addition, although irregularities of one dot occur on the side PS and the side QR of the parallelogram, no further irregularities occur in the calculation. The vertical correction control unit 10 performs the above-described processing using the pixel information storage unit 8 and the processing storage unit 9 based on a signal from the CPU 2.

<Horizontal Correction Control Unit> The processing in the horizontal correction control unit 11 is the same as the processing in the vertical correction control unit 10 described above. The conversion formula (Bb) shown in FIG. 13 is used.

<Horizontal Correction Section, Vertical Correction Section>
The horizontal correction unit 12 and the vertical correction unit 13 correct distortions due to horizontal and vertical tilt corrections, respectively, and return to the original shape. That is, by performing the above-described correction, the original image is compressed by cos θ times in the horizontal direction, and 1 × in the vertical direction.
/ Cos θ times (see FIG. 7).

Therefore, correction in the vertical direction (correction to compress in the vertical direction) can be performed by deleting each pixel in the pixel information storage unit 8 in the horizontal direction for every 1 / (1-cos θ) line (FIG. 8 (a)). Further, the correction in the horizontal direction (correction to expand in the horizontal direction) may be performed by adding one line of each pixel of the pixel information storage unit 8 in the vertical direction for each cos θ / (1−cos θ) line (FIG. 8B )reference). The information of the pixel to be added is obtained by averaging the pixel information adjacent to the left and right or by copying the pixel information of either the left or right.

The horizontal correction unit 12 and the vertical correction unit 13 perform the above-described processing using the pixel information storage unit 8 and the processing storage unit 9 based on the signal of the CPU 2. The horizontal correction unit 12 and the vertical correction unit 13
It functions as a distortion removing unit.

<Image Information Correction Processing> Next, a procedure of image information inclination correction processing in the image information inclination correction apparatus 1 according to an embodiment of the present invention will be described. FIG. 9 is a flowchart illustrating a procedure of a tilt correction process of image information in the image information tilt correction device 1 according to an embodiment of the present invention.

To correct the inclination of image information using the image information inclination correction apparatus 1 according to one embodiment of the present invention, first, as shown in FIG. 9, a document is placed on an input device such as a scanner. Read the image by operating the copy key (S
TEP0). Subsequently, the document data read by the input device is stored in the storage device (STEP 1), and it is determined whether or not the inclination needs to be corrected (STEP 2). If it is not necessary to correct the tilt, the image is displayed or printed (STEP 8). On the other hand, if the inclination needs to be corrected, the inclination of the entire document is detected from the stored data (STEP 3). Note that, as described above, various methods for detecting the inclination have been proposed, and a description thereof will be omitted.

Subsequently, a comparison is made between the detected inclination and the allowable distortion amount (STEP 4). In this case, the allowable distortion amount is
The operator may be able to select it, or the designer may determine it in advance, but in the latter case, the amount of allowable distortion is constant, and the amount of allowable distortion cannot be selected depending on the contents of the document. Further, different allowable distortion amounts may be set in the vertical direction and the horizontal direction. The above-described determination equation (1) is used to determine the amount of distortion.

As a result of the judgment, when the judgment formula (1) is satisfied, a vertical correction (STEP 5) and a horizontal correction (STEP 6) are executed. Further, the image compressed in the horizontal direction is corrected and the image expanded in the vertical direction is corrected (STEP 7), and output to a printing device or the like (ST7).
EP8).

On the other hand, if the result of the determination (STEP 4) does not satisfy the determination formula (1), the operator is informed that "the inclination is too large" (STEP 11), and the processing is interrupted (STEP 12). Here, when the operator operates the copy key or the like again (STEP 14), it is regarded that the above-described determination formula (1) is satisfied, and the above-described correction processing is performed. In the image obtained at this time, although the inclination is removed, the distortion is equal to or more than an allowable amount. When the process is interrupted, the document cover is opened and the way of placing the document is corrected, and if the copy key is operated (STEP 15), the process is restarted from the beginning. (ST
The distinction between the key operations in EP14) and (STEP15) may be made by detecting whether or not the document cover is opened or whether or not the position of the document has been changed.

[0065]

The image information inclination correcting apparatus according to the present invention comprises:
With the above-described configuration, the following effects can be obtained.

In the image information inclination correcting apparatus according to the present invention,
Based on the correlation between the detected tilt amount and the stored allowable distortion amount, it is determined whether or not to perform the tilt correction of the input image information. Therefore, since the amount of distortion can be suppressed within the specified value, useless work and erroneous copy can be prevented, and work efficiency can be improved.

Further, in the image information inclination correcting apparatus according to the present invention, the operator is notified of the amount of distortion assumed to occur at the time of correction. Therefore, the operator recognizes in advance that distortion exceeding the allowable distortion amount occurs,
The document placement method can be modified to keep the distortion within the allowable distortion amount. Therefore, useless work and erroneous copy can be prevented, and work efficiency can be improved.

Further, in the image information inclination correcting apparatus according to the present invention, the operator can set the allowable distortion amount to be stored. Whether or not distortion is allowed depends on the contents of the document, the purpose of use of the copy, or the amount of distortion. Therefore, since the allowable distortion amount can be set by the operator's judgment, useless work and erroneous copy can be prevented, and work efficiency can be improved.

Further, since the operator can select whether or not the correction processing is necessary, the work efficiency can be further improved by performing the appropriate processing based on the difference in the image information.

Further, in the image information skew correction apparatus according to the present invention, it is possible to notify the operator of numerical information relating to the re-installation position of the document. In general, when changing the setting method of a document in an image input apparatus such as a scanner or a copying machine, it is difficult to know in which direction and how much correction should be performed because the document is viewed from the back side. Therefore, by numerically expressing the re-installation position of the original,
The information about the modification can be made very easy to understand.

Further, the image information skew correction apparatus according to the present invention can remove the distortion of the image obtained by correcting the skew of the image information. Therefore, the distortion of the image after the inclination has been corrected can be corrected at high speed to restore the original image shape, so that a high-quality image can be obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a case where an image is corrected in a vertical direction and a case where an image is corrected in a horizontal direction.

FIG. 2 is a block diagram illustrating a specific configuration of an image information inclination correction apparatus according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram illustrating detection of the inclination of a document.

FIG. 4 is an explanatory diagram illustrating detection of the inclination of an image in a document.

FIG. 5 is an explanatory diagram illustrating an image distortion correction process.

FIG. 6 is an explanatory diagram illustrating correction processing in a vertical direction and a horizontal direction.

FIG. 7 is an explanatory diagram illustrating compression / expansion of an image.

FIG. 8 is an explanatory diagram illustrating compression / expansion of an image.

FIG. 9 is a flowchart illustrating a procedure of image information inclination correction processing in the image information inclination correction apparatus according to an embodiment of the present invention.

FIG. 10 is an explanatory diagram for explaining an image inclination caused by placing a document.

FIG. 11 is an explanatory diagram showing rough steps of inclination correction of image information.

FIG. 12 is an explanatory diagram of a conversion formula used in a conventional image information inclination correction method.

FIG. 13 is an explanatory diagram of a conversion formula used in a conventional image information inclination correction method.

FIG. 14 is an explanatory diagram of a conversion formula used for a conventional image information inclination correction method.

FIG. 15 is an explanatory diagram for explaining image distortion.

FIG. 16 is an explanatory diagram for explaining the necessity of tilt correction based on a difference in image information.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image information inclination correction device 2 CPU 3 Operation part 4 Document reading part 5 Image display or image printing part 6 Document size detection part 7 Display part 8 Pixel information storage part 9 Processing storage part 10 Vertical correction control part 11 Horizontal direction Correction control unit 12 Horizontal correction unit 13 Vertical correction unit 14 Key unit 15 Tilt correction required / unnecessary setting unit 16 Allowable distortion amount setting unit 21 Original document 22 Copy 23 Instruction guide 24 Image information

Claims (6)

[Claims] 1. An image processing apparatus, comprising: a tilt amount detecting means for detecting a tilt amount of image information. When image information is input while being tilted, horizontal and horizontal shifts are performed in accordance with the tilt amount detected by the tilt amount detecting means. In an image information inclination correction device for correcting the inclination of image information by moving pixel information in a vertical direction, an allowable distortion amount storage unit for storing an allowable distortion amount, and an inclination detected by the inclination amount detection unit. Correction judgment means for judging whether or not to perform inclination correction of the input image information based on a correlation between the amount and the allowable distortion amount stored in the allowable distortion amount storage means. An image information inclination correction device characterized by the above-mentioned. 2. A correction operation is performed for an operator based on a correlation between a tilt amount of image information detected by the tilt amount detecting means and a permissible distortion amount stored in the permissible distortion amount storing means. 2. The apparatus according to claim 1, further comprising an estimated distortion amount notifying unit configured to notify the estimated distortion amount.
The image information inclination correction device described in the above. 3. The image information tilt correction according to claim 1, further comprising an allowable distortion amount input unit for setting an allowable distortion amount to be stored in the allowable distortion amount storage unit by an operator. apparatus. 4. When the correction judging means judges that the inclination correction of the image information is not performed, it is derived from the inclination amount of the image information detected by the inclination amount detecting means and the document size of the image information. 4. A reset position information notifying means for notifying an operator of numerical information relating to a reset position of a document to an operator.
The image information inclination correction device according to any one of the above. 5. The image according to claim 1, further comprising a distortion removing unit for removing distortion of the image obtained by correcting the inclination of the image information. Information tilt correction device. 6. The image information tilt correction apparatus according to claim 3, wherein said allowable distortion amount input means can perform setting for not performing tilt correction.