JPH099009A - Image readers such as facsimile machines - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention relates to a facsimile device, a copying machine, an image filing system, and an image reading device using a light receiving element of a scanner. A white reference plate data storage means for storing the light receiving element output when the white reference plate is read, and an image information data storage means for storing the light receiving element output when the document is read,
The original area is detected based on the data held in the white reference plate data storage means and the image information data storage means. [Effect] Since the original area is detected after reading the original, the data in the original can be read without omission regardless of the state of the read original, and a sensor for detecting the leading edge and the trailing edge used conventionally is added. Because you do n’t have to
Cost reduction is also achieved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile machine, a copying machine, an image filing system, and an image reading apparatus using a light receiving element of a scanner.

[0002]

2. Description of the Related Art In a facsimile apparatus, a copying machine, an image filing system, and other image reading apparatus using a light receiving element of a scanner, when reading an original, the horizontal direction of the original is accurately set with respect to the scanner. There is a need to. Read image information data (image data)
If the tilt occurs, the processing of the image information data performed thereafter becomes inaccurate, and when it is received by the facsimile device, a part of the image information data may be lost, which causes inconvenience.

As one method for solving such inconvenience, at least two or more document leading edge detection sensors are provided, the document inclination is calculated from the time difference between the detection times and the distance between the detection sensors, and the inclination angle is used. There is known an image filing system in which the inclination of a document is corrected (Japanese Patent Application Laid-Open No. 2-31558). By using such a method, the inclination of the document can be corrected. However, this method requires a sensor for detecting the leading edge of the document in order to detect the leading edge of the document. Further, there remains a problem that the original area cannot be accurately recognized when the original is read while being inclined.

[0004]

SUMMARY OF THE INVENTION According to the present invention, the inclination of a set original can be corrected without the need for adding a sensor or the like for detecting the leading edge of the original, so that the inconvenience caused by the inclination of the original can be solved. Provided is an image reading device that has been resolved.

[0005]

According to the invention of claim 1, white reference plate data storage means for storing the light receiving element output when the white reference plate is read, and image information for storing the light receiving element output when the document is read. A data storage means is provided, and the original area is detected based on the data held in the white reference plate data storage means and the image information data storage means.

According to a second aspect of the present invention, in the image reading apparatus according to the first aspect, a document data line recognizing means for recognizing a document data existing line in the image information data stored in the image information data storing means is provided, and the document area is provided. Is configured to detect the image information data line by line.

According to a third aspect of the present invention, in the image reading apparatus according to the first aspect, a correction image information data storage unit for storing the corrected image information data is provided, and the image information data stored in the image information data storage unit is corrected. The inclination of the original is corrected by performing the processing and moving it to the corrected image information data storage means.

According to a fourth aspect of the invention, the image reading apparatus according to the third aspect is provided with size recognition means for recognizing the document size in the sub-scanning direction, and is configured to judge whether the document is a standard size.

According to a fifth aspect of the present invention, in the image reading apparatus according to the first aspect, the angle detection means for calculating the inclination between any two points of the image information data stored in the image information data storage means, and the image detection means. Data rotation means for rotating the information data is provided, and the inclination of the document is corrected based on the data held in the white reference plate data storage means and the image information data storage means.

According to a sixth aspect of the present invention, the image reading apparatus according to the first aspect includes means for calculating a distance between two arbitrary points in the image information data stored in the image information data storage means, and recognizes the document size. It is configured to do.

According to a seventh aspect of the present invention, in the image reading apparatus according to the first aspect, a corrected image information data storage means for storing the corrected image information data and a paper size recognition means for recognizing the paper size on the recording side are provided. By correcting the image information data stored in the image information data storage means and moving the image information data to the corrected image information data storage means, when correcting the inclination of the document, It is configured to select the rotation direction.

According to an eighth aspect of the present invention, in the image reading apparatus according to the seventh aspect, a rotation direction setting means for setting the rotation direction of the image information data at the time of correction is provided.

[0013]

In the present invention, when considering the reflectance of the white pressure plate and the reflectance of the paper, attention is paid to the fact that the reflectance of the paper is lower, and the image information data read from the original is The document area is determined, and its inclination is detected to correct the image information data (claims 1 to 8).
Invention). Therefore, at the time of reading a document, the image information of the first set document is read, and subsequently, a white pressure plate (white reference plate: a white pressure plate arranged at a position facing a light receiving element in a scanner of a facsimile machine, Further, in a copying machine or the like, the reflected light from the document pressing plate) is detected and read as white reference plate data.

FIG. 2 is a diagram for explaining the storage state of the read image data and the method for detecting the leading edge of the document in the image reading apparatus of the present invention. (1) shows the storage state of all data,
(2) is a diagram showing a method of detecting the tip. In the figure, x
Is the horizontal axis direction (x coordinate), y is the vertical axis direction (y coordinate), the solid line P is the original area, the broken line Q is the scanning range required for transmission and reception in the uncorrected state, X is the upper left corner of the original, and Y is the original area. Is the upper right corner, Z is the lower right corner, W is the lower left corner, a, c, e, g are x coordinates, b,
d, f, and h indicate y coordinates.

In the case shown in FIG. 2 (1), in the read image information data, there is an original area P shown by a solid line, and the original area P shown by the solid line is in the main scanning direction. It is tilted. In order to detect such a tilted state of the original area P, the image information data shown in FIG. 2A and the level of the white reference plate data may be sequentially compared for all areas. In this case, the comparison can be performed in the sub-scanning direction and sequentially progressing in the main scanning direction, or conversely, in the main scanning direction and sequentially proceeding in the sub-scanning direction. In the case of the former method, the image information data and the white reference plate data are sequentially compared from the tip (0 at the upper left) along the sub-scanning direction (y direction) as shown in FIG. 2 (2).

After the first comparison, the main scanning direction (x direction) is moved to perform the same comparison. Since the level of the image information data is lower than that of the white reference plate data (the reflectance is small), the position X (a,
When b) is detected, if the vicinity is sampled in the main scanning direction, the line X (a, b) -Y (c, d) shown in FIG. 2 (2) can be obtained. After such a drop in output,
Once again, if the position where the image information data and the value of the white reference plate data match is sampled, in the memory where the image information data is stored, the outline of the original, the original area of the solid line shown in FIG. You can know P.

Further, in order to transmit and receive the original area P indicated by the solid line without omission, the image information data of the scanning range Q required for the transmission and reception indicated by the broken line may be taken out. Also in this case, if all the data shown in FIG. 2 (1) are compared with the image information data and the white reference plate data, the leading end line in the main scanning direction is the X line shown in FIG. 2 (2). (A, b) -Y
It is obtained as (c, d). Also for the rear end line,
Similarly, the position Z (e, f) at the rear end and the position W (g, h) at the other rear end are detected.

Since the area surrounded by these lines (range indicated by solid line P) is the existence portion of the image information data, the range of this solid line P, that is, the coordinates (a,
The range between d) and the coordinates (e, d) may be used as effective data in the main scanning direction. Further, by performing the same processing in the sub-scanning direction, the range of coordinates (a, h) and coordinates (e, h) can be obtained. In this way, the scanning range Q shown by the broken line in FIG. 2 (1) is obtained.

[0019]

The image reading apparatus of the present invention will now be described in detail with reference to the drawings. Although this embodiment corresponds to the inventions of claims 1 to 8, the invention of claim 1 is the basic invention. In addition,
In the following, a case of a facsimile device will be mainly described, but it goes without saying that the present invention can be applied to a copying machine, an image filing system and other image reading devices. That is, all image reading devices such as a scanner using a light receiving element are included.

FIG. 1 is a functional block diagram showing an embodiment of the main configuration of the image reading apparatus of the present invention. In the figure, 1 is a CPU, 2 is a light receiving element, 3 is an image data processing unit, 4 is an image information data storage unit, 5 is a white reference plate data storage unit, 6 is a tilt angle detection unit, and 7 is corrected image information data. A storage unit, 8 is a data rotation processing unit, and 9 is a CPU bus.

The configuration and operation of the image reading apparatus of the facsimile apparatus shown in FIG. 1 common to the conventional one will be briefly described. The CPU 1 is a control unit having a function of controlling the entire system of the facsimile machine of FIG.
The light receiving element 2 receives the reflected light of the document and outputs analog data as image information data.

The image data processing unit 3 converts the analog image information data sent from the light receiving element 2 into digital data. The image information data storage unit 4 is a storage unit that stores image information data. The configuration and operation of the image reading unit described above are the same as those of the related art, and other configurations of the facsimile device are omitted.

In the image reading apparatus of the facsimile apparatus of FIG. 1, in order to detect the inclination of the set document and correct it to correct image information data (digital data),
The following blocks 5-8 are added. First, the white reference plate data storage unit 5 is a memory means for storing the data of the white pressure plate (white reference plate data) read in place of the original. The tilt angle detection unit 6 has a function of calculating the tilt of the document.

The corrected image information data storage section 7 is a memory means for storing the data in which the inclination has been corrected (corrected data). The data rotation processing unit 8 has a function of rotating the image information data. The above is the configuration and function of each newly added part in the image reading apparatus of the present invention.

Next, the operation of the image reading apparatus of the present invention during image reading will be described. When a document is set on the image reading device and a reading operation is instructed, document feeding is started and the light receiving element 2 outputs image information data. In this state, the image information data is output as analog data, read by the image data processing unit 3 and converted into digital data.

The image data converted into digital data is stored in the image information data storage unit 4. When the reading operation of all the set originals is completed, the white pressure plate is read subsequently, and the light receiving element 2
Data of reflected light from the white pressure plate is output. Similarly, the reflected light data is also output as analog data, read by the image data processing unit 3 and converted into digital data.

The output value of the digital data of the white pressure plate is stored in the white reference plate data storage section 5 as white reference plate data. With the above-described operation, in the image reading apparatus shown in FIG. 1, the image information data previously read becomes the image information data storage unit 4 like the original area P shown by the solid line in FIG. Remembered in. Further, the white reference plate data read subsequently is stored in the white reference plate data storage unit 5.

Therefore, the CPU 1 compares the image information data stored in the image information data storage unit 4 with the white reference plate data stored in the white reference plate data storage unit 5 to compare the leading end portion of the document. Is determined. The detailed processing for determining the leading edge of the document is as described in FIGS. 2 (1) and 2 (2) above.
When the position where the image information data level first drops is sampled in the main scanning direction by comparing from the tip in the sub scanning direction (y direction), the position X (a, b) shown in FIG. 2 (2) is obtained. -Y (c,
The line joined in d) is obtained. When the position where the image information data and the value of the white reference plate data coincide with each other is sampled again in the area following this line after the level of the image information data is lowered, the outer shape of the document in the image information data storage unit 4 is extracted. (Region P) can be known.

In this case, in order to transmit / receive all the data of the original area P in the image information data storage section 4 (copy output in the case of copying), the scanning range shown by the broken line in FIG. 2 (1). It is only necessary to output so that Q is included (the invention of claim 1).

The above embodiment is for detecting the scanning range Q including the document area P by detecting the leading end of the document. However, the necessary scanning range Q can be detected by detecting the original data existing line of the image information data in the image information data storage unit 4 by a simpler process. That is, in the main scanning line direction,
If the image information data of the document exists even in part, the line is set as the necessary scanning range Q, and if the image information data of the document exists in part in the sub-scanning direction, the main scanning is performed. The sub-scanning direction including the line may be set as the required scanning range Q. Also in this processing, the CPU 1 causes the image information data storage unit 4 to
The document data existing line may be detected for the image information data stored therein (the invention of claim 2). As described above, according to the image reading apparatus of the present invention, even if the set original document is tilted, the image information data of the read original document does not leak, so that all the image information on the original document can be displayed. It can be sent or copied.

By the way, in the above process, the image information data of the read document does not leak, but when the document is read with a tilt, the data in the image information data storage section 4 also remains tilted. If such image information data is transmitted or copied, an image with poor image quality will be recorded. Therefore, in the image reading apparatus of the present invention, when the original is read in a tilted state, the tilt of the image information data stored in the image information data storage unit 4 is corrected, so that high-quality image transmission or copy is performed. Is enabled (the inventions of claims 3 to 6).

In the apparatus shown in FIG. 1, the corrected image information data storage unit 7 (the invention of claim 3) or the tilt angle detection unit 6 is used.
By adding (invention of claim 5), the inclination correction process of the image information data is performed. As described in Fig. 2 (1) and (2) above, the comparison process between the image information data and the white reference plate data is performed from the edge in the sub-scanning direction, and the level drops first. Is stored in the corrected image data storage unit 5 as the first data of the first line. Next, the portion of the adjacent line where the level first drops is stored as the second data.

Such processing is performed by the image information data storage unit 4
If all the image information data stored therein are processed, the corrected image data storage unit 5 can obtain the image information data in which the inclination generated when the document is read is corrected. In this case, the reason for carrying out in the sub-scanning direction is that in the cases of FIGS. 2 (1) and 2 (2), the vertical center line of the document is inclined from the upper left to the lower right. By performing such a correction process, it is possible to store image information data that does not cause a deviation with respect to the document (the invention of claim 3).

In this process, the document size in the main scanning direction can be recognized, but the size in the sub scanning direction is not particularly recognized. Therefore, by providing size recognition means for recognizing the document size in the sub-scanning direction,
It is possible to determine whether the original is a standard size (the invention of claim 4). If the original is tilted in the direction opposite to that shown in Fig. 2 (1) or (2) (when the vertical center line of the original is tilted from the upper right to the lower left), the scanning is performed in the main scanning direction. More accurate correction is possible.

In the above correction processing, it is necessary to compare all data, so the correction operation becomes complicated. In order to simplify such a correction process, as shown in the apparatus of FIG. 1, a tilt angle detection unit 6 and a data rotation processing unit 8 are provided, and the tilt of the image information data is detected to detect the tilt. Is corrected, a high quality image can be obtained (the invention of claim 5). In this case, as the outline line of the document shown in FIG. 2 (2), the coordinates X (a, b) and Y (c,
If the position of d) is obtained, the inclination angle θ between the line and the main scanning direction can be calculated by a trigonometric function.

After that, the data rotation processing unit 8 may rotate the image information data stored in the image information data storage unit 4 by the obtained tilt angle θ. Since the corrected image information data is stored in the corrected image information data storage unit 7, it is possible to transmit or transfer the image information data in which the inclination of the document is corrected. By the way, when originals of different sizes are mixed, it is necessary to perform different correction processes respectively. Therefore, a means for calculating the distance between any two points in the image information data stored in the image information data storage unit 4 is provided (the invention of claim 6).

A means for calculating the distance between two arbitrary points in the image information data is also realized by the CPU 1 and can recognize the document size. More specifically, if the positions of both ends of the document obtained for calculating the tilt angle θ of the document, that is, the data of the coordinates X (a, b) and Y (c, d) are used, the range between XY is obtained. The distance (original size) can be calculated.

Therefore, the size of each original can be recognized, and the image information data can be accurately read even if originals of different sizes are mixed. The flow of the correction operation of the image information data of the image reading apparatus of the present invention described above is shown.

FIG. 3 is a flow chart showing the main processing flow when correcting image information data in the image reading apparatus of the present invention. In the figure, # 1 to # 9
Indicates a step.

In step # 1, the original is set, and in step # 2, when the start switch is operated, the process proceeds to step # 3. In step # 3, document feeding is started.
In step # 4, the read image information data (A) is stored in the image information data storage unit 4 of FIG.

In step # 5, the data of the reflected light of the white pressure plate, that is, the white reference plate data (B) is stored in the white reference plate data storage unit 6 of FIG. In step # 6, the image information data (A) is compared with the white reference plate data (B), and A <B
The part that becomes is detected (X, Y detection). Step # 7
Then, the distance between X and Y (original size) is calculated.

In step # 8, the inclination θ of the document is calculated. In step # 9, the image data is rotated by θ by the data rotation processing unit 8 to be corrected, stored in the corrected image data storage unit 5 of FIG. 1, and the operation flow of FIG. 3 is ended. By the above processing, the image data in which the inclination of the document is corrected is obtained in the corrected image data storage unit 5 (the inventions of claims 1 to 6). It should be noted that Z in FIG. 2 (2)
If the position of (e, f) is known, the distance between Y and Z can be obtained (added between steps # 7 and # 8 in FIG. 3). By such processing, it becomes possible to know the vertical and horizontal sizes of the document, and it is possible to determine whether or not the document has a standard size (the invention of claim 6).

By the way, the above correction process is performed on the reading side and is independent of the recording paper size on the recording side. Therefore, a paper size recognition unit for recognizing the paper size on the recording side is provided, and the rotation direction of the image information data is selected according to the recording paper (the invention of claim 7). For example,
If the image information data is rotated in a direction suitable for the recording paper as compared with the recording paper data in the case of an irregular size or the like, the recording paper can be saved.

Further, some users may want to rotate the image information data stored in the image information data storage unit 4 of FIG. 1 so as to match its orientation with the reading direction when correcting the inclination. . For example, in the case of an A4 size original, the copier should be set sideways,
In a facsimile machine, generally, when transmitting, it is set vertically. Therefore, a rotation direction setting means for setting the rotation direction of the image information data at the time of correction is provided (claim 8).
Invention). As described above, by enabling the rotation direction of the image information data to be set, the operability is further improved.

[0045]

According to the first aspect of the invention, the original area is detected after the original is read. Therefore, regardless of the state of the read original, the data in the original can be read without omission, and it is not necessary to add a sensor for detecting the leading edge and the trailing edge, which has been conventionally used, and thus cost reduction can be achieved. .

According to the second aspect of the present invention, since the original area can be detected line by line in the image information data stored in the image information data storage unit 4, the original area can be specified by a simple process. It will be possible. According to the third aspect of the invention, even if the document is tilted during reading, the tilt of the image information data stored in the image information data storage unit 4 can be corrected. Therefore, high-quality image data can be obtained regardless of the inclination of the original.

In the third aspect of the invention, the document size in the main scanning direction is recognized, but the document size in the sub-scanning direction is not recognized, so it cannot be determined whether the document is a standard size. Challenges remain. Claim 4
In the invention, since the size recognition means for recognizing the document size in the sub-scanning direction is added, it is possible to judge whether the document has a standard size.

According to the invention of claim 5, with respect to the image information data stored in the image information data storage unit 4, an inclination angle detecting means for calculating an inclination of the data and a data rotation processing means for rotating the image information data. Is provided. Therefore, even if the document is tilted at the time of reading, high-quality image data irrelevant to the document tilt can be obtained.

In the invention of claim 5, the size of the original cannot be judged because the size of the original is not recognized. According to the sixth aspect of the invention, since the size recognition means for recognizing the document size is added, the document size can be recognized for each document, and it is possible to read the document in which different sizes are mixed.

For example, in the case of an A4 size original, the copier is set in the horizontal direction, but in the facsimile,
Generally, it is set vertically when sending. In the fourth aspect of the present invention, it is possible to determine whether the original has a standard size, but it is not possible to specify the rotation direction of the image information data. According to the seventh aspect of the invention, the rotation direction of the image information data can be designated according to the paper size on the recording side, so that the recording paper can be saved. In the invention of claim 7, the user cannot select the rotation direction. In the invention of claim 8, since the rotation direction setting means for setting the rotation direction of the image information data at the time of correction is added, the operability is further improved.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing an embodiment of the main configuration of an image reading apparatus of the present invention.

FIG. 2 is a diagram illustrating a storage state of read image data and a method of detecting a leading edge of a document in the image reading apparatus of the present invention.

FIG. 3 is a flowchart showing a main processing flow when correcting image information data in the image reading apparatus of the present invention.

[Explanation of symbols]

 1 CPU 2 Light receiving element 3 Image data processing unit 4 Image information data storage unit 5 White reference plate data storage unit 6 Tilt angle detection unit 7 Corrected image information data storage unit 8 Data rotation processing unit 9 CPU bus

Claims (8)

[Claims] 1. A white reference plate data storage means for storing an output of a light receiving element at the time of reading a white reference plate, and an image information data storage means for storing an output of the light receiving element at the time of reading an original, the white reference An image reading apparatus such as a facsimile apparatus, which detects an original area based on the data held in the plate data storage means and the image information data storage means. 2. The image reading apparatus according to claim 1, further comprising a document data line recognition means for recognizing a document data existing line in the image information data stored in the image information data storage means, wherein the document area is defined as image information data. An image reading device such as a facsimile device, which detects a line by line. 3. The image reading apparatus according to claim 1, further comprising a corrected image information data storage unit for storing the corrected image information data, and performing correction processing on the image information data stored in the image information data storage unit. An image reading apparatus such as a facsimile apparatus which corrects the inclination of a document by moving the document to the corrected image information data storage means. 4. The image reading apparatus according to claim 3, further comprising size recognition means for recognizing a document size in the sub-scanning direction, and determining whether or not the document is a standard size. . 5. The image reading apparatus according to claim 1, wherein, with respect to the image information data stored in the image information data storage means, an angle detection means for calculating an inclination between arbitrary two points and the image information data are rotated. An image reading apparatus such as a facsimile apparatus, which comprises data rotating means, and corrects the inclination of an original based on the data held in the white reference plate data storing means and the image information data storing means. 6. The image reading apparatus according to claim 1, further comprising means for calculating a distance between two arbitrary points in the image information data stored in said image information data storage means, and recognizing a document size. Image reading devices such as facsimile machines. 7. The image reading apparatus according to claim 1, further comprising: a corrected image information data storage unit for storing the corrected image information data, and a paper size recognition unit for recognizing a paper size on the recording side. By correcting the image information data stored in the storage means and moving it to the corrected image information data storage means, when correcting the inclination of the document, the rotation direction of the image information data is changed according to the recording paper. An image reading device such as a facsimile device characterized by being selected. 8. The image reading apparatus according to claim 7, further comprising a rotation direction setting unit that sets a rotation direction of the image information data at the time of correction.