JPS63149770A - Picture distortion correcting system - Google Patents

Abstract

PURPOSE:To correct a picture distortion well even when a form other than a specified format is used by performing a distortion correction by means of calculating a distortion quantity at the time of the input of a drawing on the basis of the predetermined condition of a rid spacing and the condition of a grid number. CONSTITUTION:A multiple storage circuit 26 stores the basic number of the grid number, which is optionally set, and a grid spacing storage circuit 28 stores the grid spacing, which is set in the form set in a scanner, and a distortion calculation circuit 24 calculates the respective quantities of and inclination distortion and a parallel movement distortion of the drawing, on the basis of the coordinate of a grid position detection mark M, which is detected from an input data by a mark detection circuit 20 and is positioned at the respective vertex of a rectangle, complemented by a mark complement circuit 22 as occasion demands, and on the basis of the respective stored values of the multiple storage circuit 26 and the grid spacing storage circuit 28. A distortion modification circuit 30 modifies the coordinate of an object picture in the drawing inputted from an information transformation circuit, on the basis of the inputted quantity of the parallel movement distortion.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a drawing reading device that optically reads human handwritten drawings and obtains necessary information.
In particular, this paper relates to improvements in image distortion correction methods.

B1 Summary of the Invention This invention provides an image distortion correction method that corrects distortion at the time of inputting an image by using position detection marks of a grid that normalizes the image. , based on the data regarding the number of lattices between the lattice position detection marks and the coordinate data of the detected lattice position detection marks, the distortion calculation means calculates the amount of distortion that occurs when inputting the image, and the distortion correction means corrects the distortion. By doing so, it is possible to perform image distortion correction satisfactorily even when using paper other than special format paper.

C1 Prior Art An example of a drawing reading device that optically reads a handwritten drawing by a person and converts the image data of the obtained drawing into necessary information by performing the necessary processing is shown in Fig. 2. There is.

In FIG. 2, the paper on which the drawing is drawn is scanned by the scanner 90.
The scanner 90 optically reads the image.

The output side of the scanner 90 is connected to the input side of the information conversion circuit 92. This information conversion circuit 92 performs predetermined processing on the input image data and converts it into necessary data, so the converted data is output.

The output side of the information conversion circuit 92 is connected to the input side of a result output circuit 94, and the result output circuit 94 outputs the above-mentioned converted data.

By the way, the drawing paper set in the scanner 90 generally includes a grid (or grid pattern) drawn in a color to which the scanner 90 does not respond, in order to assist the creator's drawing work.

As the output of the result output circuit 94, it is often desired that the target image in the drawing be normalized onto the nearest grid.

D1 Problems to be Solved by the Invention However, for example, paper is subject to distortion due to expansion and contraction. Also, when setting paper in the scanner 90, rotational distortion and translational distortion occur.

If the above distortion exists, there is a risk that when the target image is simply normalized to the lattice assumed in the coordinate system inside the device, it may not be normalized well to the lattice desired by the creator. There is an inconvenience.

Conventionally, in order to correct such distortion, a special format paper on which grating position detection marks are printed in advance is used, and after the distortion is corrected using this paper, the image is normalized.

However, this means has disadvantages such as having to use special format paper and not being able to handle various other types of paper.

The present invention has been made in view of this problem, and it is an object of the present invention to provide an image distortion correction method that can be favorably applied to paper other than special format paper.

E. Means for Solving Problems The present invention provides a first storage means for storing data regarding grid spacing, a second storage means for storing data regarding the number of grids between grid position detection marks, and a first storage means for storing data regarding the number of grids between grid position detection marks. In addition, the present invention is characterized by comprising a distortion calculation means for calculating the amount of distortion using the coordinate data of the grid position detection mark, and a distortion correction means for correcting the distortion of the image based on the calculated amount of distortion. It is.

F1 Effect According to the present invention, paper other than paper in a special format can also be used. The distortion calculation means uses the data stored in the second storage means to calculate the distortion, and the distortion correction means further corrects the distortion.

G. Embodiments Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 3 shows an example of a drawing reading device to which the present invention is applied. In this figure, the output side of the scanner IO on which the paper on which the read image is drawn is connected to the input side of the information conversion circuit I2, and the image data of the optically read drawing is transferred to the information conversion circuit 12. It is becoming more and more human-powered.

Next, the output side of the information conversion circuit 12 is connected to the input side of the strain F+Ii positive circuit 14. This distortion correction circuit 14 corrects the rotational distortion and translational distortion when setting the paper described above, and the details will be described later.

The output side of the distortion correction circuit 14 is connected to a result output circuit 18 via a normalization circuit 16.

This normalization circuit 16 normalizes the target image into a grid assumed as an internal coordinate system.

Next, the distortion correction circuit 14 mentioned above will be explained with reference to FIG.

One output side of the information conversion circuit 12 described above is connected to the input end of a mark compensation circuit 22 via a mark detection circuit 20, and the output side of this mark compensation circuit 22 is as follows.
It is connected to the input terminal of the strain calculation circuit 24.

The input terminal of this strain calculation circuit 24 is connected to the multiple storage circuit 2.
6. A grid spacing storage circuit 28 is connected to each. Further, the output side of the distortion calculation circuit 24 is connected to a distortion correction circuit 30.
is connected to one input end of the

The other output side of the information conversion circuit 12 described above is connected to the other input side of the distortion correction circuit 30, and the output side is connected to the normalization circuit I6.

Among the above six circuits, the mark detection circuit 20 first selects a grid position detection mark from input data and outputs the coordinates of the mark.

The input data may be in any form such as pixel data or vector data. In addition, the grid position detection mark can be distinguished from other elements in the drawing, and its position can be specified at one point.
Anything can be used as long as it is detectable.

Here, the operation of the mark detection circuit 20 when the grid position detection mark is cross-shaped and the input data is vector data will be explained with reference to FIG.

First, as shown in step SA in Fig. 4, from 1 point to 4
It is determined whether the vector of the book appears. The cross-shaped mark corresponds to a pattern in which four hands extend from one point.

Next, as shown in step SB, it is determined whether or not another vector emerges from the opposite end point of each vector.

Then, as shown in step SC, it is determined whether each of the four vectors forms two sets of straight lines.

If any one of the above conditions is not met, the mark does not fall under the cross-shaped mark. However, if all the conditions are met, the mark is a cross-shaped mark, that is, a grid position detection mark, and the coordinates of the first detected point are output as shown in step SD.

Next, the mark compensation circuit 22 generates and compensates for grid position detection marks so that the grid positions can be detected satisfactorily even when there are, for example, three grid position detection marks on the paper.

For example, as shown in FIG. 5, grid position detection marks M1, M2, . When M3 is detected by the mark detection circuit 20, the lattice position detection mark M4 corresponding to the remaining vertices is compensated by the mark compensation circuit 22.

Next, the multiple storage circuit 26 stores the base number of the grid number arbitrarily set by the user of the apparatus. A rectangular area is formed by the aforementioned grid position detection marks, and the number of grids included in one side of this rectangle must be a multiple of the basic number stored in the multiple storage circuit 26.

For example, in the case of the stored basic number rlJ, the number of lattices included in one side of the rectangle is l, 2, 3, . ...is possible. In addition, when the basic number is "4", the grid number is 4, 8, 1
2. ... becomes possible.

Next, the lattice interval storage circuit 28 stores the lattice interval set in the paper set in step 10, and its value is appropriately rewritten when the paper is changed.

Next, the distortion calculation circuit 24 calculates the coordinates of marks MA to MD located at each vertex of the rectangle as shown in FIG. The above-mentioned multiple storage circuit 2
6. The tilt distortion and translation distortion of the drawing are calculated based on the values stored in the grid spacing memory circuit 28, and the operation thereof is shown in FIG.

In FIG. 7, first, the grating position detection mark MA
The inclination distortion ΔO of the drawing is determined from each coordinate value of MD to MD (see step SE).

Next, based on the obtained tilt distortion 80, the tilt distortion of the coordinate values of each mark MA to MD is corrected (see step SF'). Then, using the corrected coordinate values, between each mark, that is, between MA-M13,
The number of grids included between MA and MC, between MC and MB, and between MB and MB is stored in the multiple storage circuit 26. Lattice spacing memory circuit 2
Determined by referring to the stored value of 8 (see step SG)
.

For example, if the width between M A - M 8 is LA and the grid spacing is LL, the basic loss LI3. For a suitable integer N, the following calculation is performed: LA/LL=N-LB.

Next, the number of grids between MA and MB and the number of grids between MC and MD are compared (see step SH), and if they do not match, a rejection output is performed (see step S), and if they match, then In this step, the number of grids between MA and MC and the number of grids between MB and MD are compared (see step SJ). When the two do not match, a rejection output is similarly performed.

When the two match, the translational distortion amount is calculated (see step SK), and the distortion range is further output to the distortion correction circuit 30 (see step SL).

Next, the distortion correction circuit 30 corrects the coordinates of the target image in the drawing manually entered by the information conversion circuit 12 based on the amount of distortion of the parallel movement entered manually, and the corrected coordinates are transferred to the normalization circuit. It is designed to be output on 1 '6.

Note that, as described above, this normalization circuit 16 determines the reference point of the target image in the drawing, that is, the point that should be on the grid,
This is a circuit that normalizes by applying it to the nearest grid point.

Furthermore, since the distortion correction circuit 14 is configured as described above, the following conditions are required for the grating and the grating position detection mark.

First, regarding the grid position detection marks, ■ They must be drawn on the grid. ■ Each side must be located at each vertex of a rectangle whose sides are parallel to the grid axis of the paper. ■ At least three marks must be drawn. It is necessary that the number of gratings included in one side of the rectangle formed by the grating position detection marks is a multiple of the basic number stored in the multiple storage circuit 26. However, the value of the basic number may be different on each side of the rectangle.

Next, the overall operation of the above embodiment will be explained. First, a drawing is set on the scanner 10.

Preferably, this drawing is a drawing drawn on a sheet of paper printed with a grid that does not react to the scanner lO, roughly following the grid, or a drawing drawn assuming a grid on paper without a grid printed on it. .

The image of the drawing is optically read by the scanner IO, and the image data is manually input to the information conversion circuit 12.

Next, the information conversion circuit 12 performs necessary processing on the manually input image data, converts it into pixel data, vector data, etc., and inputs it to the distortion correction circuit 14 .

Next, the distortion correction circuit! 4, first the mark detection circuit 2
0, a grid position detection mark is selected, and the coordinate values of the mark are input to the mark compensation circuit 22.

The mark compensation circuit 22 compensates for the marks if necessary, and the coordinate values of the four grid position detection marks are input to the distortion calculation circuit 24. This strain calculation circuit 24
The basic number is inputted from the multiple storage circuit 26, and the lattice spacing is inputted from the lattice spacing storage circuit 28.

Next, the distortion calculation circuit 24 performs the processing shown in FIG. 7 to calculate the amount of distortion, which is then applied to the distortion correction circuit 3.
0 is man-powered.

In the distortion correction circuit 30, distortion correction is performed on the data output from the information conversion circuit 12 based on the manually inputted distortion amount, and the corrected pixel data is obtained.

Vector data etc. are sent to the normalization circuit 16.

The normalization circuit 16 applies the reference point of the target image to the nearest grid point, and the result is output to the result output circuit 18.

As explained above, this embodiment has the following effects.

First, by storing multiples and lattice spacing, it is possible to satisfactorily correct distortion when inputting paper other than special format paper. In particular, errors caused by expansion and contraction of paper can be corrected well by storing multiples.

Next, mark compensation is performed, so even if only three grid position detection marks are drawn, or if one mark is missing for some reason even if four grid position detection marks are drawn, the result will be correct. The amount of distortion can be calculated and corrected.

Note that the present invention is not limited to the above-mentioned embodiments; for example, a mark compensation circuit may be provided as necessary.

Furthermore, if there is no multiple storage circuit or if the set basic number is rlJ, there is a high possibility that the rejection output shown in step Sl in FIG. 7 will be performed due to the expansion and contraction of the paper.

However, the basic number is "2".

rq J, r4'', etc., the distortion type output of step SL is performed.

H. Detailed Description of the Invention As described above, according to the present invention, the amount of distortion at the time of drawing input is calculated based on the grid spacing condition and the grid number condition that are predetermined and stored, and distortion correction is performed. Therefore, there is an effect that even when using paper other than the special format, image distortion correction can be performed satisfactorily.

[Brief explanation of the drawing]

FIG. 1 is a circuit block diagram showing one embodiment of the present invention, and FIG.
The figure is a circuit block diagram showing an example of a conventional device, and FIG. 3 is a circuit block diagram showing an example of a drawing reading device to which the present invention is applied.
Figure 4 is a flowchart showing the operation of mark detection;
The figure is an explanatory diagram showing an example of detected grid position detection marks,
FIG. 6 is an explanatory diagram showing an example of lattice position detection marks for strain calculation, and FIG. 7 is a flowchart showing the operation of strain calculation. 14... Distortion correction circuit, 20... Mark detection circuit, 22... Mark compensation circuit, 24... Strain calculation circuit, 26... Multiple storage circuit, 28... Grid spacing storage circuit, 30 ...distortion correction circuit, Ml to M4.
MA or MD: Grid position detection mark. Figure 1 Figure 2 Figure 3 Figure 5 Figure 6

Claims (2)

[Claims] (1) In an image distortion correction method that optically reads an image to be processed and uses detected grid position detection marks to correct distortion at the time of inputting the image, data regarding the spacing of the grid for normalizing the image. a first storage means for storing data on the number of grids between the grid position detection marks; a second storage means for storing data on the number of grids between the grid position detection marks; the data respectively stored in the first and second storage means; and a distortion correction means for correcting the distortion of the read image based on the calculated distortion amount. An image distortion correction method characterized by: (2) The image distortion correction method according to claim 1, wherein the distortion calculation means includes mark compensation means for compensating for marks in accordance with the number of detected grating position detection marks.