JP2002010059A - Image processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically detect plural documents and to output images onto sheets of paper in different modes such as for alignment of inclination when the plural documents are placed on a document table. SOLUTION: When read image data D1 are data of plural documents OR1, OR2, etc., which are placed on a document table 9 and are read at the same time, the document edges E1, E2, etc., of document image data d1, d2, etc., in the read image data D1 are detected by a document edge detecting section 5 according to difference in density. The plural document image data d1, d2, etc., are cut down by a plural document detecting section 6 according to the detected document edges E1, E2, etc., and, after processing such as individual alignment of inclination by a plural document processing section 7, images are output onto sheets 10 of paper by an image output device 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus for reading image data of a document placed on a document table of a document input device, processing the obtained image data, and outputting the processed image data.

[0002]

2. Description of the Related Art In an image forming apparatus (copying machine) having a normal copying function, when reading an original, the original is placed directly on an original platen or the original is fed by an automatic original feeder. The document is conveyed on a table, and the document is read by an optical system in a state where the document cover is further covered.

The copying machine has a function of automatically detecting the size of the document and selecting an appropriate sheet for copying (automatic sheet size selection function), an automatic magnification selection function, a black frame erasing function, and the like. Is normal. Then, in order to detect the document size in each of the above functions, the contour (edge) of the document placed on the document table is detected. There is also an apparatus that performs skew correction based on a detected document edge. These conventional apparatuses are based on the premise that one document is placed on a document table.

[0004]

However, when a plurality of originals are placed on an original platen, respective original images are copied on the front and back of the same copy paper, or are aligned in the same copy paper area. You want to copy. At this time, it is difficult to align a plurality of original images or to correct the original images to a predetermined arrangement or inclination, and erroneous copying is often performed.

[0005] In this regard, no suitable device has been proposed yet. That is, in the case of detecting and copying an edge of a document placed on the platen, the conventional skew correction technology assumes that only one document is placed on the platen, When multiple originals are placed, edge detection and skew correction cannot be performed, and originals placed on the platen are output as they are (tilted originals are tilted) and output (copy etc.) I just stay.

The present invention provides an image processing apparatus capable of automatically detecting a plurality of originals when a plurality of originals are placed on an original platen and outputting an image to a sheet according to various modes. It is intended to be.

[0007]

Means for Solving the Problems In order to achieve the above object, the present invention is configured as follows.

The present invention processes read image data obtained by reading image data of a document placed on a document table of a document input device, and processes the processed image data by an image output device. In the image processing apparatus for outputting, when the read image data is obtained by simultaneously reading a plurality of document images placed on a document table, a document edge detecting unit that detects a document edge of each document image data in the read image data A plurality of document detection units that cut out each document image data from the read image data based on the detected document edge, and perform processing such as individually adjusting the inclination of each cut out document image data and outputting the data to paper A plurality of original processing units are provided.

The image processing apparatus of the present invention detects an original edge of original image data in the read image data when the read image data is obtained by simultaneously reading a plurality of original images placed on an original platen. Since multiple document image data is cut out based on the detected document edge, by placing multiple documents on the platen, it is possible to process multiple documents simultaneously with one copy button operation, Operability is improved. In addition, since the plural original processing units perform processing such as individually adjusting the inclination of the extracted plural original image data, there is no need to worry about the inclination of the original when placing it on the original platen.

Here, as a technique for cutting out a plurality of document image data from the read image data based on the detected document edge, an edge tracking method, a labeling method, or the like can be used.

A plurality of document processing units for individually outputting the cut-out document image data; a mode for arranging and outputting the document image data on one sheet of paper;
Alternatively, a mode may be provided in which each of the document image data is divided into front and back sides of a sheet and both sides are copied. When a plurality of originals are placed on an original platen of an image input device (for example, a scanner) and these plurality of originals are read simultaneously, individual original image data can be recognized, and individual original image data can be read. Various output processes used can be performed.

The multiple document processing section determines whether or not the document image data cut out from the read image data is a rectangular document, and if the document image data is determined to be a rectangular document, performs processing on the rectangular document image data. A function for performing skew correction and aligning the directions can be provided. According to this function, it is possible to obtain an effect that, when copied, the originals are aligned and the copy is not unsightly.

When outputting a plurality of document image data individually, the plurality of document processing units automatically select a sheet suitable for each document size, reduce an image, etc., and perform individual image printing on an output sheet. Can be provided. According to this function, when the document is letter size and the copy paper is A4, the letter size document image is A4 size.
Reduced to fit on paper.

The plural document processing units may have a function of defining the order of each document image data when individually outputting a plurality of document image data cut out from the read image data. According to this function, by placing the order as specified in advance at the time of copying,
They can be output in order.

When the at least one of the document image data cut out from the read image data is determined to be a document having an arbitrary shape other than a rectangular shape, the plural document processing section displays a document edge with a broken line or the like from the edge detection result. An output function can be provided (claim 7). According to this function, the original document shape can be identified by the dashed line, so that it can be used for copying a pattern paper or the like, and can be cut along the dashed line with scissors after copying.

When arranging the original image data cut out from the read image data on a single sheet and printing the original image data, the plurality of original processing units cause the original image data to be arranged and output such as a blank / broken line or an equal interval. Functions can be provided. According to this feature, when a plurality of originals are simultaneously printed on one sheet, an effect is obtained that the copies are easy to see because they are arranged in consideration of balance.

The plural document processing section can have a function of performing double-sided copying of a plurality of documents with the directions of the documents being matched. According to this feature, by placing two originals, double-sided copying can be performed with one copy button operation.

The plural document detecting section has a function of forcibly separating and cutting out the document image data even when a part of the plural documents overlaps in the read image document. be able to. According to this feature, partially overlapped originals can be determined and aligned.

Further, the present invention can have a function of sequentially processing a plurality of original documents in parallel with the reading of the original image by the image input device. According to this feature, it is not necessary to store the memory for the entire screen of the read image data, so that the apparatus can be realized with a small memory capacity.

Further, the present invention can be provided with a function of performing a plurality of document processing after reading the entire image memory. According to this feature, there is an advantage that the processing is simple and the processing speed is high.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the illustrated embodiment. FIG. 1 shows a configuration diagram of an image processing apparatus according to the present embodiment. The image processing apparatus 1 performs predetermined processing on the read image data D1 input from the image input apparatus 2, and outputs the image data on which the image processing has been performed to the image output apparatus 3.
Output. Further, the image processing apparatus of the present invention may have the function of an image input device and / or an image output device as an image input unit and / or an image output unit. The image processing apparatus 1 includes an image memory 4, a document edge detecting unit 5, a plurality of document detecting units 6, a plurality of document processing units 7, and a mode setting unit 8.

The image input device 2 is, for example, a scanner or a digital camera. In the processing according to the present embodiment, as shown in FIG. OR2 ... is read and the read image data D1 is transmitted to the image processing apparatus 1. When a digital camera is used as the image input device 2, the originals OR1, OR2... To be read are plain originals so that edges of the originals OR1, OR2. It must be placed on the table 9. Also, the larger the density difference between the color of the document table 9 and the background color of the document, the easier the edge detection of the document (the possibility of erroneous detection is reduced).

The image data D1 read by the image input device 2 is stored in the image memory 4 in the image processing device 1. At this time, it is not always necessary to store the data for all the images, and it is also possible to sequentially execute the processing in the image processing device 1 described below in parallel with the image data reading by the image input device 2. . The document edge detection unit 5 detects document edges E1, E2,... Based on the density difference between the document table 9 and the image data D1 stored in the image memory 4, and outputs edge information EG.
Output as

The plurality of original detecting units 6 refer to the edge information EG detected by the original edge detecting unit 5 to convert each original OR included in the original image data D1 from the original image data D1.
1, OR2 ... image data d1, d2 ... (represented by D2 in FIG. 1) are cut out. Further, the plurality of original processing units 7 apply the original image data D2 (d1, d2...)
An image output mode M such as an individual print mode set and designated by the mode setting unit 8 (FIG. 3B)
According to (d)), processing such as skew correction and selection of an optimum paper size corresponding to each mode is performed, and the result is output as processed image data D3.

The image output device 3 receives the image data D3 processed by the image processing device 1, and outputs the image data D3 onto one rectangular copy sheet 10 or respective copy sheets 10a, 10b,. 3).

Next, the processing operation of the image processing apparatus 1 will be described mainly with reference to the flowchart of FIG.
First, an image output mode is set in order to determine the output format when outputting the read original (S1). As the screen output mode, in the case of this embodiment, modes such as (1) double-sided copy, (2) multiple originals are arranged on one sheet of paper, and (3) one original copy on each sheet (individual print mode). (FIGS. 3B to 3D)
There is.

More specifically, FIG. 3A shows a plurality of originals OR1, OR2... (Here, two originals OR1 shown as "original 1" and "original 2") on an original platen 9 of the image input apparatus.
And the document OR2) are placed. Original OR
1 and the document OR2 have a rectangular shape and edges E1, E2
2 are placed on the document table 9 in an irregular state. The image data D <b> 1 obtained by reading the plurality of originals at a time is sent to the image processing apparatus 1. In the image processing apparatus 1, the document edge detector 5 detects edges E1 and E2 of each document image from the density difference with respect to the document table 9, receives the edge information EG, and causes the plurality of document detectors 6 to output individual document image data. d1,
Cut out as d2.

The above-mentioned "(1) double-sided copy" mode (FIG. 3
(B)) is a mode in which the images corresponding to the respective document image data d1 and d2 cut out individually are output as a double-sided copy on the front and back of one sheet of paper 10. FIG.
In the example shown in (b), the document OR having the largest document size
1 (original 1), the printing paper size is selected, and the original OR2 (original 2) smaller than this is copied on the back side of the same paper. Even in the case of three or more originals, printing can be performed on one sheet as long as two or more of the originals can be arranged on the same surface of the printing paper.

The above-mentioned "(2) Arranging a plurality of originals on one sheet"
The mode (FIG. 3C) is a mode in which the individual cut-out original image data d1 and d2 are rearranged on one print sheet 10 and output. Here, in the read image data, when the rectangular originals OR1 and OR2 (originals 1 and 2) have inclination, the skew processing is performed to correct the inclination and equalize the inclination, and the arrangement interval of each original image data d1 and d2 is set. Set appropriately (for example, set at equal intervals)
Correction and the like are performed.

In the above-mentioned "one original copy on each sheet" mode (FIG. 3D), the original image data d1 and d2 cut out individually are printed on separate print papers 10 respectively.
This is a mode for outputting in a and 10b. Here, for the rectangular original OR1 (original 1), the printing paper 10a of the specified size (A4, B5, A3, etc.) corresponding to the original size is selected, and for the arbitrary-shaped original OR2 (original 2), the outer rectangular Optimal paper size 10b depending on the shape of
Select Further, for example, when the document size is letter size and the closest paper size is A4, the image can be reduced and output on A4 size paper.

Returning to the flowchart of FIG.
When the image output mode is set in step S1, the plurality of originals OR are placed on the original table 9 of the image input device as shown in FIG.
1. With the OR2 placed, image reading is performed over the entire image reading area (S2). In response to the read image, a document edge detection unit 5 of the image processing apparatus
The document edges E1 and E2 are extracted (S3).

Here, an example of a method for detecting a document edge will be described. The read image data D1 stored in the image memory 4 has a horizontal and vertical configuration, and represents each pixel as coordinates. Then, the read image data D
The image on the document table 9 having the read image area 11 as shown in FIG.
As shown in (a), a horizontal scan (scan 1) and a vertical scan (scan 2) are performed.

FIG. 4B is a graph of the density level obtained by the horizontal scanning. In the graph showing the density level, a portion where the density ratio exceeds a predetermined threshold value is detected as an edge of the document by using information on the density of the document cover (normally a white plate) and the density of the document. A flag is set for a pixel corresponding to an edge portion above. In the example of FIG. 4, the boundary in FIG. 4B where the density level changes before and after the threshold value is identified as the X-direction edges E1a and E1b of the document OR1 (document 1).

Similar processing is performed on the result of the vertical scan, and the boundary where the density level changes before and after the threshold value in FIG. 4C is determined by the original OR1 (original 1) and the original OR2 (original 2) in the Y direction. Edges E1c, E1d, E2c, E2
The pixel corresponding to these edge portions is flagged on the image memory 4 after being identified as d.

By performing the horizontal and vertical scans on the entire surface of the read image data D1, the document edge E
1, E2 is extracted. In addition to this, a method of extracting edges using a differential filter is also known, and such other known edge detection methods can be used.

Returning to the flowchart of FIG. 2 again, when the document edges E1 and E2 are detected, a document image is cut out based on the detected edge information EG (S).
4). For example, the edge tracking method shown in FIG. 5 and the labeling method shown in FIG. 6 can be used as the document cutting method.

The following briefly describes the edge tracing method (1) to (5) (see FIG. 5).

(1) In the read image data (FIG. 5) after the document edge has been extracted, scanning from left to right is performed from top to bottom in order from the top pixel row (Y = 1 pixel row). The process is sequentially performed so as to move to a pixel row, and a search is performed for a pixel determined as a document edge (a pixel with a flag).

(2) Starting from the edge pixel first detected by the above scanning, 8 pixels around the edge pixel
The pixels determined to be edge pixels are tracked with respect to neighboring pixels. At this time, it is assumed that the pixel at the various positions of the eight neighboring pixels is checked leftward (or rightward), and the edge pixel that appears first is tracked.

(3) The above process (2) is performed on the tracked edge pixels. (4) When the above process (3) is repeated and the process returns to the start edge pixel, a closed boundary is detected, and the document image data d1 or d2 is cut out. (5) In the read image data after the document image data d1 or d2 is cut out, the continuation of the process of (1) is performed to start a newly detected edge pixel.
By repeating the above processes (2) to (4), a plurality of original image data d are added to the read image data D1.
When both d1 and d2 are included, all of them can be cut out.

Returning to the flowchart of FIG. 2, it is determined whether or not each document image data cut out by the process of S4 is a rectangular document (S5).
In this determination, the linearity of the boundary line of the document is detected from the coordinate series. If the document is composed of four straight lines, the document is determined to be a rectangular document. If the number of straight line segments is 6 or more and the intersection angle of the straight lines is 90 or more at 6 places, and it is determined that the document is one sheet (overlapping), the document is cut at a portion where each straight line is extended. , To separate the overlapping documents.

If it is determined in step S5 that the document is a rectangular document, the skew is detected by skew determination (S6), and the image is rotated (skew correction) parallel to the document table to align the image orientation (S7). ).

For the method of skew detection and skew correction, known methods disclosed in, for example, JP-A-10-65877 and JP-A-5-274475 can be used. The brief description is as follows. That is, first, the skew angle (the inclination angle with respect to the original table) is detected based on the inclination of the straight line viewed from the original table, and then, based on the inclination angle, the inclination of the original is corrected by, for example, affine transformation or the like.

In step S5, a circumscribed rectangle is determined for the original image data determined to be an original of an arbitrary shape (S8). Further, depending on the set mode, a dashed line process is performed on the original edge (original). Add dashed line data corresponding to the document edge to the image data) (S
9). Here, when obtaining the circumscribed rectangle of the arbitrary-shaped document, the maximum and minimum XY coordinates from a closed coordinate series serving as the boundary line of the document are obtained, and a rectangle having these coordinates as a range is defined as a circumscribed rectangle. (See FIG. 7).

The dashed line processing is performed on the document edge.
For the following purposes: That is, when the document is of an arbitrary shape, the shape of the document may be important, such as a pattern, for example. Treatment such as cutting out becomes easy.

When the processes of steps S6 to S9 are completed, the currently set image output mode is determined (S10). If the individual print mode (the mode in FIG. 3D) has been set, the optimum paper size for each document image data is selected (S11). In this process, first, the vertical and horizontal sizes of the document are detected from each document image data, and the specified paper (A4, B5, B4, A3, etc.) having the same size or the closest size is selected. Note that, for an original of an arbitrary shape, the size of the circumscribed rectangle is set as the original size.

Here, the above-mentioned original size is compared with the size of the selected standard paper.
The original image is arranged such that the center of the original and the center of the prescribed paper are aligned. If the original does not fit on the specified paper, the original image is reduced based on the larger vertical / horizontal over-ratio, and the original image is arranged with the center of the reduced original and the center of the specified paper. When the arrangement of the document image data and the paper is completed, copying of each document is performed (S1).
2).

As for the document cutting in step S4, the description of this flow shows an example in which, when one document image data is cut out, the process shifts to the next stage for this data. Step S1
When one document image is output in step 2, it is determined whether or not processing of a plurality of documents has been completed, that is, whether or not document cutout processing has been completed in all areas of the read image data (S13). If not completed, the process proceeds to step S4, where the next original is cut out by the method described above, and the same processing is performed thereafter.

If the simultaneous print mode (the mode shown in FIGS. 3B and 3C) has been set in the process of step S10, it is necessary to cut out a plurality of original images before performing the output process. There is. Therefore, step S10
After this mode determination, it is determined whether or not the cutout processing of a plurality of documents has been completed (the same processing as in step S13). When the processing for cutting out a plurality of originals is completed, processing related to output, such as alignment processing for a plurality of originals and optimal paper size selection processing, is executed (S14).

In the process of step S14, the following processes (1) to (3) are performed.

(1) In the case of the double-sided copy mode shown in FIG. 3 (b). An optimum paper size is selected from a plurality of original data according to the maximum original size. Same as). The original is arranged on the selected specified paper in the same manner as in the case of individual printing (the center of the original is aligned with the center of the specified paper).・ Align the image orientation on the front and back of the paper.

(2) In the case of the one-sided copy mode shown in FIG. 3C. The following alignment processing is performed on the cut-out document. -Align the center line of the long side of the specified paper with the center line of each document. -The long sides of the prescribed paper are arranged so that the document edge and the document are at the same pitch.

(3) When one original is copied on each sheet shown in FIG. 3D. The cut-out original is copied based on a predetermined order.

[0054]

As described above, according to the present invention, when the read image data is obtained by simultaneously reading a plurality of documents placed on a document table, the document edge of each document image data in the read image data is read. Is detected by the document edge detection unit based on the density difference, and based on the detected document edge, a plurality of document image data are cut out by the plurality of document detection units, and the plurality of document processing units perform processing such as individually adjusting the inclination. Since a plurality of originals are placed on a platen, a plurality of originals can be processed simultaneously by one copy button operation, thereby improving operability. In addition, the multiple original processing unit converts the extracted multiple original image data into
Since processing such as individually adjusting the inclination is performed, there is no need to worry about the inclination of the original when placing the original on the platen.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an image processing apparatus capable of processing a plurality of documents according to the present invention.

FIG. 2 is a diagram illustrating a flowchart (copy example) of the image processing apparatus according to the present invention.

FIG. 3 is a diagram illustrating an example of processing a plurality of originals in the image processing apparatus according to the present invention.

FIG. 4 is a diagram illustrating an example of a document edge detection method in the image processing apparatus of the present invention.

FIG. 5 is a diagram illustrating an example of cutting out a plurality of documents (edge tracking method) in the image processing apparatus of the present invention.

FIG. 6 is a diagram illustrating an example of cutting out a plurality of documents (labeling method) in the image processing apparatus according to the present invention.

FIG. 7 is a diagram illustrating a method of extracting a rectangle of an arbitrary-shaped document in the image processing apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image processing device 2 Image input device 3 Image output device 4 Image memory 5 Original edge detecting unit 6 Multiple original detecting unit 7 Multiple original processing unit 8 Mode setting unit 9 Original platen 10, 10a, 10b ... Copy paper 11 Read image area D1 Read image data D2 (d1, d2...) Image data of each document E1, E2... Document edge E1a, E1b X-direction edge EG Edge information M Image output mode OR1, OR2.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H027 DB09 DB10 DC19 FA11 FA13 FB11 FB12 FB13 FD00 FD01 FD08 ZA07 2H028 BA02 BB02 5C072 AA01 AA03 AA05 BA09 BA10 LA02 RA04 WA02 WA08 XA01 5C076 AA02 AAA AAA AA AA AB AA AA AB AA AA AB A

Claims (13)

[Claims] An image output device processes read image data obtained by reading image data of a document placed on a document table of a document input device, and outputs the processed image data by an image output device. In the image processing apparatus, when the read image data is obtained by simultaneously reading a plurality of document images placed on a document table, a document edge detection unit that detects a document edge of each document image data in the read image data; A plurality of document detectors that cut out each document image data from the read image data based on the detected document edge, and perform processing such as individually adjusting the inclination of each cut document image data so that it can be output to paper. An image processing apparatus, comprising: 2. The image processing apparatus according to claim 1, wherein the plurality of document processing units have a mode for individually outputting the cut-out document image data. 3. The image processing apparatus according to claim 1, wherein the plural document processing units have a mode in which the document image data is arranged and output on one sheet. 4. The image processing apparatus according to claim 1, wherein the plurality of document processing units have a mode in which each of the document image data is divided into front and back sides of a sheet and both sides are copied. 5. The multi-document processing section determines whether or not the document image data cut out from the read image data is a rectangular document. The image processing apparatus according to claim 1, further comprising a function of performing skew correction on the image data and aligning the directions. 6. The multi-document processing section automatically selects a sheet corresponding to each document size when individually outputting a plurality of document image data, and performs image reduction or the like to output a sheet. 3. The image processing apparatus according to claim 2, further comprising a function of arranging the images as individual images. 7. When the plurality of document processing units determine that at least one of the document image data cut out from the read image data is a document having an arbitrary shape other than a rectangular shape, a broken line is added to the document edge from the edge detection result. The image processing apparatus according to any one of claims 1 to 6, further comprising a function of outputting the image data. 8. When the plurality of original processing units arrange and print original image data cut out from read image data on one sheet of paper, an arrangement such as a blank / dashed line or an equal interval is provided between these original image data. 4. The image processing apparatus according to claim 3, further comprising a function of outputting. 9. The multi-document processing unit has a function of defining the order of each document image data when individually outputting a plurality of document image data cut out from the read image data. The image processing apparatus according to claim 2. 10. The image processing apparatus according to claim 4, wherein said plurality of document processing units have a function of performing double-sided copying of a plurality of documents with the orientations of the documents matched. 11. The multi-document detecting section according to claim 1, wherein said plurality of documents are partially overlapped in said read image document.
11. The image processing apparatus according to claim 1, further comprising a function of performing a correction for forcibly separating and cutting out the document image data. 12. The image processing apparatus according to claim 1, further comprising a function of sequentially processing a plurality of original documents in parallel with reading of an original image in the image input device. 13. The image processing apparatus according to claim 1, further comprising a function of performing a plurality of document processes after reading the entire image memory.