JPH0231558A - Method for correcting inclination of picture data and picture filing system adopting thereof - Google Patents

Abstract

PURPOSE:To correct the inclination of picture data without giving any restriction to originals while a large quantity of originals are inputted by detecting the inclination of the originals by means of sensors arranged in the direction perpendicular to the original carrying direction and correcting the inclination of the picture data. CONSTITUTION:A leading edge detecting sensor group 22 is constituted of plural sensors 220, 221, 230 and 231 arranged in the direction perpendicular to the carrying direction 24 of an original 10. For example, the sensors 230 and 231 are arranged in the longitudinal direction with an interval of L1 between them and detect the right- and left-side leading edges of the original 10 of A4 size, etc., and sensors 220 and 221 are arranged in the longitudinal direction with an interval of L2 between them and detect the right- and left-side leading edges of an original of A3 size, etc. Then, by using a trigonometric function obtained by dividing the deviated quantity DELTAX of the original 10 obtained from the difference between the leading edge detecting time by the sensor interval L1 or L2, the inclined angle (tantheta) of the original 10 is calculated and the inclination of the picture data is corrected. Therefore, the inclination of picture data, if any, can be corrected without giving any restriction to originals while a large quantity of originals are inputted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image data tilt correction method for correcting the tilt of input image data, and an image filing system to which the method is applied.

[Conventional technology]

Recent image filing systems are configured to read image data written on a document using an input means such as an image scanner, and register this image data on a recording medium such as an optical disk.

In this image filing system, when the document set in the image scanner is tilted, the document image 100 should be displayed horizontally on the display section 9 as shown in FIG. There is a problem in that, by registering the image data on the recording medium, when the image data retrieved later is displayed on the display unit 9, a tilted original image 100 is displayed as shown in FIG. 7 Φ).

In order to prevent this display of image data from being skewed, conventional technology has developed a technique that corrects the skew of the document by detecting it using a timing mark placed in a horizontal position on the document at the time of image data input, and a technique that corrects the skew of the document by adjusting the density of the written portion of the document. A technology that detects cumulative values and corrects the slope.

A technique has been proposed in which read image data is once displayed on a display unit and an operator visually adjusts the tilt of the image. Note that techniques related to these tilt corrections are disclosed in, for example, Japanese Patent Application Laid-Open No. 58-222382 and Japanese Patent Application Laid-Open No. 58-72275.
No. 61-187082, etc. In addition, the image data rotation process itself was
It is disclosed in Japanese Patent No. 2-533.

[Problem to be solved by the invention]

The above-mentioned technology that uses timing marks to correct the tilt of image data has the disadvantage that the timing marks must be placed on the original in advance, which limits the types of originals that can be used. For example, if the image part of the original is not horizontal to the original, such as a drawing, there is a possibility of incorrect correction. There was a problem that required checking and adjustment. Therefore, these conventional techniques have a problem in that they are not suitable for an image filing system that continuously inputs a large amount of general documents because they impose limitations on input documents, impose a heavy burden on the operator, and slow down the input speed.

An object of the present invention is to eliminate the problems caused by the prior art, and to correct the tilt of image data when a large number of originals are input without any restrictions on the originals. An object of the present invention is to provide a method for correcting the tilt of image data and an image filing system to which the method is applied.

(Means for solving !111) In order to achieve the above object, the image data tilt correction method according to the present invention provides at least two document leading edge detection sensors spaced apart by a predetermined distance perpendicular to the conveying direction of the document, The amount of document deviation is detected based on the difference in the leading edge detection time between the two document edge detection sensors, and the tilt angle of the document is calculated using a trigonometric function obtained by dividing this document shift amount by the sensor interval. It is characterized by correcting the head of data.

Further, in the image filing system according to the present invention, an input unit, such as an image scanner, that reads image data of a document includes at least two document leading edge detection sensors spaced at a predetermined interval perpendicular to the document conveyance direction, and a document detection sensor that detects the document document by using the document leading edge detection sensors. A calculating means for calculating the amount of document deviation based on the difference in the leading edge detection time, and a dividing means for calculating the inclination angle of the original by dividing the original deviation calculated by the calculating means by the sensor interval, and using the inclination angle. The second feature is to correct the tilt of image data. Furthermore, the third feature of the image filing system according to the present invention is that the processing device corrects the tilt of the image data using the tilt angle obtained from the input section, and the input section corrects the tilt of the image data using the tilt angle. The fourth feature is that the image data is transferred to the processing device after the tilt is corrected. In this system, the input section includes a size detector that detects the document size, and a plurality of pairs of document leading edge detection sensors that are selectively driven according to the document size detected by the size detector. 5 characteristics.

[Effect]

The method for correcting the tilt of the image data is to calculate the tilt angle of the document using a trigonometric function obtained by dividing the amount of document deviation obtained from the difference in the leading edge detection time by the two document leading edge detection sensors by the sensor interval. By correcting the skew of image data using , it is possible to input a large amount of originals without placing any restrictions on the originals, and to correct the skew of the image data if the image data is skewed.

In addition, the image filing system according to the second feature includes an input section that calculates an amount of document deviation based on a difference in document leading edge detection times by two document leading edge detection sensors, and a calculation means that calculates an amount of document deviation by dividing the amount of document deviation by the sensor interval. By providing a calculation means for calculating the tilt angle of the image data, it is possible to input a large amount of originals without any restriction on the originals, and to correct any skew in the image data. Furthermore, according to the third feature of the present invention, the processing device performs tilt correction based on the tilt information obtained from the input unit, so that the tilt correction process of the image data can be performed in parallel with the reading by the image scanner. Processing time can be shortened. According to the fourth feature, since the input section itself performs the tilt correction process on the image data, it is possible to perform the tilt correction process on the image data only by improving the input section without making any changes to the host device. According to the fifth feature, by providing the input unit with a document size detector and multiple pairs of document leading edge detection sensors that are selectively driven according to the document size, multiple types of documents with different sizes can be detected. The tilt of the document can be detected and corrected.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an image data tilt correction method according to the present invention and an image filing system to which the method is applied will be described in detail below with reference to the drawings.

First, the image filing system according to this embodiment has a first
As shown in the figure, there is an image scanner 1 that reads image data of a document, an image memory 3 that temporarily stores the read image data, etc., an optical disk 8 that stores a plurality of image data, and a CRT display section that displays the image data. 6 and the C
A CRT display memory 4 that stores image data to be displayed on the RT display section 6, a display control section 5 that controls the display section 6 and the memory 4, a keyboard 7 that inputs operator instructions, etc., and input image data that will be described later. An image rotation unit 40 that performs rotation processing, and a processing device (CPU) that controls these
2.

The scanner 1 includes, as shown in FIG. and a plurality of feed rollers 15 for discharging
and the pinch roller 16, and the document 10 on the glass plate 23.
a light receiver 21 that irradiates light from a light source 18 and receives the reflected light through a reflecting mirror 19 and a lens 20; and a group of front end detection sensors that detect left and right edges of the document 10 being transported. 22, and an arithmetic circuit for calculating the inclination angle of the original 10.The leading edge detection sensor group 22 consists of a plurality of sensors arranged at right angles to the transport direction 24 of the original 1°, as shown in FIG. sensor 220.221,
230,231, for example sensors 230 and 23
Sensors 220 and 221 are arranged at intervals of a vertical width L1 to detect the left and right edges of an A4 size document 10, and sensors 220 and 221 are arranged at intervals of a vertical width Lt to detect the left and right edges of an A3 size document. It is arranged so that

As shown in FIG. 5, the arithmetic circuit unit that calculates the inclination angle of the transported original 10 based on the detection timing of the original 10 detected by the leading edge detection sensor group 22 detects the leading edge of the original 10 of A3 or B4 size. Sensors 220 and 221
A large document detection unit 100 detects an A4. B5.
Sensors 230 and 231 detect the leading edge of A5 size document 10.
A small original detecting section 101 that detects a small original, and the detecting section 10
an O/A circuit 283 that takes the logical sum of the outputs of 0 and 101; a counter 30 that counts the output of the OR circuit 283 until it is reset for each document by a reset (RES) signal 31; By inputting the integrated value of the deviation amount ΔX of the document and the signal 28 or 28 indicating the size of the document being transported, the deviation amount ΔX is divided by the width of each sensor according to the document size, L. Divider 3 that calculates the tilt angle (tanθ) of the original 10
5, a control section 3 for controlling these via a pass line, a bus driver 32 for connecting the counter 30 to the pass line, and a bus driver 34 for inputting the document size to the pass line.

The large document detection unit 100 detects a large document size A3 or B4.
OR circuit 281 which receives as input the large document signal 28 indicating
, an EOR circuit 26 which takes the exclusive OR of the detection signals 220' and 221' from the sensors 220 and 221, and an EOR circuit 26 which takes the exclusive OR of the detection signals 220' and 221' from the sensors 220 and 221;
The detection signal 220', 221' of the original 10 is shifted due to the skew of the original 10, and the output of the EOR circuit 26 rises in proportion to this amount of shift ΔX. CL while
K27 outputs a plurality of pulse signals from the AND circuit 29. Similarly, the small original detection unit 101 includes an OR circuit 282' which receives the small original signal 284 as an input, and detection signals 230' and 23' from the sensors 230 and 231.
An EOR circuit 261 that takes an exclusive OR of 1, and an EOR circuit 282 and an EOR
and an AND circuit 291 that calculates the logical product of the outputs of the circuit 261.
While the output of 61 is rising, CLK 27 is used to manually input the signal from the AND circuit 291 to the arithmetic circuit unit by a detector provided in a plurality of document guiding mechanisms.

In the image filing system configured in this way, when registering image data, the scanner 1 shown in FIG. In this case, arbitrary image data is read from the optical disk 8 according to an instruction from the keyboard 7, and stored in the CRT display memory 4, so that the display control section 5 displays the image data on the CRT display section 6. In the image filing system according to the example, when registering the image data, the scanner 1
A tilt of 0 is detected, the tilt is corrected by the image rotator 40, and then the image is registered on the optical disc 8.

This tilt correction operation will be explained below with reference to FIG. 2 and subsequent figures.

First, the original 10 set in the scanner 1 shown in FIG. The sheet is conveyed by the feed roller 15 and the pinch roller 16 to the tip detection sensor group 22 on the glass 13 . ° At this time, the A4 size original 10 is Δ
If there is a skew of χ, the scanner 1 detects that it is a small document using a detector (not shown), and the sensor 230 first detects the right edge of the document 10.

As a result of this detection, the arithmetic circuit shown in FIG.
91. The AND circuit 291 receives these signals 28
When the clock 27 is applied while inputting the signals 4 and 230', the clock 27 is input to the counter 30 through the OR circuit 283. This clock 27 is the document 1
This continues until the sensor 231 detects the left edge of 0 and inputs the detection signal 231'' to the EOR circuit 261. In other words, this small original detection circuit 101 generates the signal between the detection of the right edge of the original and the detection of the left edge of the original. The clock 27 is input to the counter 30. The counter 30 that counts the clock 27 during this period transfers a count value proportional to the deviation amount ΔX of the original document 10 to the division circuit 35 via the bus driver 32. Based on the detection signal 284 of the small original manually inputted via the bus driver 34, it is known that the sensor interval is L+, and by dividing the counted value by the sensor interval l, 1, the inclination angle of the original 10 (tan θ ) is calculated.

After calculating this tilt angle, the scanner 1 then scans the original 10.
The document 10 is conveyed onto the glass 13 by the feed roller 15 and the pinch roller 16, and the light StS is applied from the bottom surface to the document 10.
, and this reflected light is transmitted to the reflecting mirror 19 and the lens 20.
The image data of the document is read manually by the light receiving sensor 21 via the light receiving sensor 21 . This read image data is
As shown in the figure, the information is reported to the processing device 2 of FIG. 1 through the interface 36 along with the tilt angle information 38 of the document. Upon receiving this report, the processing device 2 transfers the image data from the scanner I to the image rotator 40 according to the angle information 3 days.
After rotating it, it is stored in the image memory 3, and then CR
'F Display on the display section 6 and register on the optical disc 8.

In addition, in this embodiment, the original lO is large .DELTA.3. B
In the case of 4 originals, sensors 220 and 221 of scanner 1 detect both edges of the original, and the detection signals 220° and 221
In the same manner as described above, the large document detection circuit 100 in FIG. 30 counts this clock 27.

This count value and the large document signal 284 are sent to the bus driver 32.
．． 34 to the division circuit 35, the division circuit 35 divides the counted value by the sensor interval L2 to calculate the tilt angle '(tan θ) of the original lO.

Thereafter, the processing device 2 performs tilt correction by rotating the image data of the document based on this tilt angle, as described above. This rotation processing of image data is carried out, for example, by
This is carried out using the technique disclosed in Publication No. 3.

In this way, in this embodiment, the scanner 1 detects the inclination of the document using two sensors arranged perpendicular to the document transport direction, and the processing device 2 corrects this inclination before displaying it on the CR7 display section 6. etc.

Incidentally, in the above embodiment, the processing device 2 is the image rotator 4.
Although we have shown an example of correcting the tilt of image data using 0,
The present invention is not limited to this, but may be configured such that an image rotator for performing tilt correction is provided inside the scanner and the image is transferred to the processing device after the tilt correction is performed. Furthermore, although an example has been shown in which sensors for detecting the edges of large and small originals are provided separately, this sensor may be one that automatically moves depending on the size of the set original, for example.

As described above, the image data tilt correction method according to the present embodiment and the image filing system to which this method is applied calculate the tilt angle of the document using two document leading edge detection sensors arranged perpendicular to the document transport direction, and By correcting the inclination of image data using , it is possible to correct any inclination in the image data while manually processing a large amount of originals without placing any restrictions on the originals. Further, according to this embodiment, the processing device performs tilt correction based on the tilt information obtained from the input section, so that the tilt correction process of the image data can be performed in parallel with the reading by the image scanner. , processing time can be shortened. Furthermore, by providing the input section with a document size detector and multiple pairs of document leading edge detection sensors that are selectively driven according to the document size, it is possible to detect the tilt of multiple types of documents of different sizes. Can be corrected.

Therefore, the image filing system according to the present embodiment can display image data whose inclination has been corrected on the display unit even if the original is inputted at an angle when reading the original.

[Effects of the Invention] As described above, according to the present invention, in an image filing system, the inclination of the document is detected by the sensor arranged in the direction perpendicular to the document conveyance direction, and the inclination of the image data is corrected. If there is a skew in the image data, it can be corrected while inputting a large amount of originals without any restrictions.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of an image filing system to which the image data tilt correction method according to the present invention is applied;
Fig. 2 is a diagram showing an embodiment of an image scanner that reads image data of a document, Fig. 3 is a diagram for explaining a sensor for detecting document inclination of the image scanner, and Fig. 4 is a diagram showing image data and image inclination. A diagram showing information, FIG. 5 is a diagram showing an arithmetic circuit section for calculating the document tilt of the image scanner,
FIG. 6 is a diagram for explaining the inclination of the original, and FIG. 7 is a diagram showing the displayed image data of the original.
is a diagram showing the state in which the original is displayed normally, Figure 7 [
]) is a diagram showing a state where the document is tilted. 1... Image scanner, 2... Processing device, 3...
- Image memory, 4... CRT display memory, 5... Display control section, 6... CRT display section, 7... Keyboard, 8... Optical disk, 10... Original, 22... Leading edge detection sensor group, 24... Original transport direction, 38...
Tilt angle information, 39... Image data, 220, 221
, 230, 231...Tip detection sensor. Agent Patent Attorney Tadashi Akimoto Actual Figure Figure 221f! Wrinkle chart chart

Claims (5)

[Claims] (1) In an image data skew correction method in which image data of a document being transported is read and the skew of the read image data is corrected, at least two A document leading edge detection sensor is provided, the amount of document deviation is detected based on the difference in the leading edge detection time by the two document leading edge detection sensors, and the document inclination angle is calculated by dividing the document deviation amount by the sensor interval. A method for correcting the tilt of image data, the method comprising correcting the tilt of image data using a tilt angle. (2) In an image filing system in which image data of a transported document is read by an input section, and this image data is stored in a storage device by a processing device, the input section is spaced at a predetermined interval in a direction perpendicular to the direction in which the document is transported. at least 2
two document leading edge detection sensors, a calculating means for calculating the amount of document deviation based on the difference in the document leading edge detection time by these document leading edge detection sensors, and a calculating means for calculating the amount of document deviation by the calculating means, and calculating the tilt angle of the document by dividing the amount of document deviation by the calculating means by the sensor interval. An image filing system comprising: a dividing means for calculating, and correcting the tilt of image data using the tilt angle. (3) Claim 2, wherein the processing device corrects the tilt of the image data using the tilt angle obtained from the input section.
Image filing system as described in section. (4) The image filing system according to claim 2, wherein the input section corrects the inclination of the image data using the inclination angle and then transfers the image data to the processing device. (5) a size detector in which the input section detects the document size;
5. The image filing system according to claim 3, further comprising a plurality of pairs of document leading edge detection sensors that are selectively driven according to the document size detected by the size detector.