JPH0865457A - Image input device - Google Patents

Abstract

PURPOSE: To attain the reading of an original image of an optional size by which the tilt of image information read partially is corrected and synthesized without the need for other accessory than a scanner by detecting and correcting the tilt of read scanning from read image information so as to synthesize the image CONSTITUTION: A video camera 401 picks up the entire image of an original 101, an image read section 103 converts the information into a digital signal for each picture element and the converted signal is stored in an entire image memory 402. Then the original 101 is divided into, e.g. four and each part is picked up. Then an angle correction section 105b calculates how much a character arrangement direction is tilted with respect to a horizontal direction and a vertical direction based on image information in a partial image memory 104 to correct the image so that the character arrangement direction is set to the horizontal direction or the vertical direction and the result is stored in the partial image memory 104. The four partial images in the partial image memories 104 whose tilt angle is corrected are processed into one image by an image synthesis section 403 based on the image information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus, and more particularly, to a portable image input apparatus capable of reading a large-sized original by dividing it with a video camera and combining the divided originals.

[0002]

2. Description of the Related Art When an image reading function is added to a portable information terminal, a small and lightweight handy scanner is required as a reading sensor. Two types of handy scanners are possible. One uses a fixed focus line sensor used in conventional facsimiles. In this scanner, the sub-scan is manually performed by the operator. The other is an imaging device represented by a video camera with a variable focal length. In this case, small and lightweight 2
Since a three-dimensional image sensor is used, it is possible to read image information for one document at a time. However, the resolution is lower than that of the line sensor, and it is difficult to read the characters in the read image.

When these reading scanners are used as image input means of a portable information terminal, there are two problems.

The first problem is that since the operator moves the scanner by hand, it is not always possible to read horizontally or vertically with respect to the arrangement of characters and the like on the document. On the other hand, as shown in a portable copying machine, there has been proposed a method of manually scanning in the vertical direction with respect to a document by means of a document fixing means and a guide for guiding a scanner (JP-A-1-41373). Gazette).

The second problem is that, when a line sensor is used, the main scanning read width of the sensor becomes short in consideration of portability. Further, when the two-dimensional sensor is used, the resolution that can be discriminated cannot be obtained unless it is read close enough to the original, and therefore one original cannot be read at a time. Since both the line sensor and the two-dimensional sensor read a document by dividing it into small parts, it is necessary to combine it with the original image information later. On the other hand, by placing a document on a board on which a sensor for detecting the position of a handy scanner is spread in the image input device and scanning, the relative position of each image read in a divided manner is detected, and the image is detected. A method of synthesizing has been proposed (Japanese Patent Laid-Open No. 2-52565). Further, a method has been proposed in which an alignment mark is provided on a document in advance and the images read by dividing are combined so that the alignment marks match each other (Japanese Patent Laid-Open No. 2-159678).

[0006]

As described above, the document fixing means, the scanner guide, the position detection board, etc. are troublesome to handle and inconvenient to carry. Furthermore, in the method of putting the alignment mark on the manuscript, it is necessary to put the mark on the manuscript, and especially in the case where there is no margin to put the mark on the manuscript, the characters of the manuscript, etc. There is a problem that the characters are hidden by the mark and there are places where the characters cannot be entered because of the mark.

The object of the present invention is to solve the above-mentioned problems and to read the original image of any size which can correct the inclination of the partially read image information and synthesize it without the need for accessories other than the scanner. An image input device is provided.

[0008]

Means for Solving the Problems The gist of the present invention for solving the above problems is as follows.

(1) Two-dimensional image reading means, correction means for correcting the scanning angle of the image read by the two-dimensional image reading means, storage means for storing the angle-corrected entire image, and angle-corrected partial image A storage unit for storing the partial image, a storage unit for storing the partial image, a storage unit for storing the composite image, a size conversion unit for converting each of the image information into an arbitrary size, each of the image information and each of the storage units. The image input device includes a display unit that displays the stored image information in an arbitrary size.

(2) The above-mentioned image having a combining means for reading the whole image and a partial image obtained by dividing the whole image into a plurality of parts, and combining the partial images into one image based on the position information of each partial image based on the whole image information. It is in the input device.

(3) In the image input device, the display means is a display means that is converted into a size that can be stored in the image display unit based on image information and is displayed.

(4) When the display means displays the entire image on the image display section, the display means can distinguish the read partial image area and the unread image area from each other. In the image input device described above.

(5) The display means is in the image input device, which is a liquid crystal display device.

(6) The two-dimensional image reading means is in the image input device which is a video camera.

[0015]

According to the present invention, the video document is photographed by moving the video camera away from the document to obtain image information of the entire document. Next, the video camera is brought close to the document and divided into a plurality of parts for shooting to obtain partial image information. After that, the inclination angle is corrected for the whole image and the partial image, position information of the partial image in the whole image is calculated, and the partial images are combined based on this position information to obtain the whole image.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a system configuration using a video camera which is a movable focus type two-dimensional image scanner as a two-dimensional image reading means.

The original 101 is read by a portable video camera 401 including a two-dimensional image sensor and a lens. The image reading unit 103 is means for converting an analog signal input from the video camera 401 and corresponding to the density of one pixel unit into a digital signal. This is an AD using a semiconductor element.
It can be realized with a converter. The partial image memory 104 is a storage unit for storing image information read by the video camera 401, and can be realized by a semiconductor memory.

The entire image memory 402 is used by the video camera 4
A storage unit of the whole image information of the original 101 read in 01 can be realized by a semiconductor memory. The angle correction unit 105
This is a correction unit that corrects a deviation in the main scanning direction and the sub-scanning direction with respect to the arrangement of characters on the document 101 when the operator manually moves the video camera when reading the document 101. A concrete realizing means will be described later based on FIG.

The image synthesizing unit 403 is used for the partial image memory 10
A plurality of partial read images stored in
This is a synthesizing means for converting into one piece of image information corresponding to 01. A concrete realizing means will be described later based on FIG.

The composite image memory 107 is a storage means for storing the combined image information for each original, and can be realized by a semiconductor memory.

When the operator displays the image information on the image display unit 109, the size conversion unit 108 reduces or partially enlarges the image in order to confirm the whole image, or displays the image from the resolution of the video camera 401. A size conversion unit that performs a process of converting the resolution of the unit 109. Specifically, a register for setting the size conversion rate and a logic circuit for thinning out or adding pixel signals based on the conversion rate set in the register, for example, when the size conversion rate of 5/6 is set, The entire image size is reduced to 5/6 by thinning out one pixel for every 6 consecutive pixels in the main scanning direction and the sub scanning direction to make 5 pixels. When 3/2 is set, one pixel is added to every two consecutive pixels in the main scanning direction and the sub-scanning direction to make 3 pixels, thereby enlarging the entire image size to 3/2. These are the latch circuits,
It can be realized by a logic circuit such as a counter, a logical sum, and a logical product.

The image display unit 109 also displays the read image information and also serves as an operation panel for the operator to input processing instructions. For example, it can be realized by using a liquid crystal display device and arranging a touch sensor for converting a touch of a user's finger or a pen into an electric signal on the display surface.

The portable information terminal 110 comprises the video camera 4
01 is electrically connected by wire or wirelessly.
The auxiliary functions include, for example, a schedule management function equivalent to an electronic system notebook, a handwriting input function of character information with a special pen on the image display unit 109, a processing instruction, and a facsimile function, and other information terminals. And a function capable of transmitting and receiving image information. This is an infrared photoelectric transfer device, a microprocessor and a read-only memory for storing a program for controlling the microprocessor, a readable / writable memory for storing image information,
It can be realized by combining a modem and the like.

Next, the operation will be described with reference to FIG.
Although the video camera 401 is a small and lightweight portable type, its resolution is low, and therefore it is often difficult to read minute character information in the original when the entire original is photographed. Therefore, it is necessary to bring the video camera closer to the original or to enlarge the original so as to partially read the image information and combine the divided and recorded image information into the image information of one original.

An example will be described in which the original 101 is divided into four parts, that is, the upper, lower, left and right parts, and the image is read. First of all,
The video camera 401 captures an entire image of the original 101, and the image reading unit 103 converts this information into a digital signal for each pixel and stores it in the overall image memory 402. At this time, since the operator manually moves the video camera 401 and fixes the video camera 401 at the time of shooting, it is difficult to always read the document, for example, horizontally (or vertically) with respect to the line of characters. Therefore, the angle correction unit 105a calculates from the image information in the partial image memory how much the direction of the character arrangement is inclined with respect to the horizontal and vertical directions, so that the character arrangement direction becomes the horizontal (or vertical) direction. It is corrected and stored again in the whole image memory 402.

The angle-corrected image information is size-converted and displayed by the size conversion unit 108 so that the entire image can be displayed on the image display unit 109. This allows the operator to know whether the entire image of the original 101 has been read.

Next, the operator divides the original 101 into four, for example, the upper right portion is photographed by the video camera 401. For this photographing, the video camera 401 is brought close (or enlarged) to the original 101 and photographed, so that the read character information is enlarged and the characters can be read. This image information is stored in the partial image memory 104.

Next, the angle correction unit 105b calculates from the image information in the partial image memory how much the direction of the character arrangement is inclined with respect to the horizontal and vertical directions, and the character arrangement direction is horizontal (or vertical). ) Direction, and again stores it in the partial image memory 104. The images divided into four as described above are sequentially read, the tilt angle is corrected, and the images are stored in the partial image memory 104.

Each of the four partial images in the partial image memory 104 in which the respective tilt angles have been corrected and stored is combined by the image combining unit 403 into one image based on the image information.

The combined image information is stored in the combined image memory 10
7, and the size conversion unit 108 converts the composite image into a size that can be displayed and displays the composite image on the image display unit 109. Note that the entire image is displayed on the image display unit 10 each time the images are combined.
9, the area where partial image information is not captured has the display color inverted or blinked so that the operator can confirm the uninput area in the entire image. It is preferable. As a result, the operator can confirm the presence / absence of a non-input area and deal with it.

FIG. 2A shows an angle correction unit 1 in FIG.
The processing of No. 05 is shown. The area of each character is detected from the image information read by the character area detection unit 201. This processing is performed, for example, on the pixel portion where the high-density portion of the character “B” shown in FIG. 2C is continuous in the tilted image information 204 in the partial image memory 104 shown in FIG. 2B. End point 206, bottom point 207, left end point 20
8. Detect the pixel coordinates of the right end point 209. Specifically, the adjacent area of a total of 9 pixels of the main scanning 3 pixels and the sub-scanning 3 pixels from the partial image memory 104 is sequentially stored in the latch circuit, and each end point is sequentially compared by the detection template and the comparator, and they match each other. In this case, the end point is determined. These can be realized by a register file storing a template and a logic circuit.

Next, a quadrangle 20 having the above-mentioned end points on its side.
5 is defined. This process is simply (x coordinate of left end point, y coordinate of upper end point), (x coordinate of right end point, y coordinate of lower end point)
It is realized by setting the two coordinate points of the above in a register composed of flip-flops. The tilt angle calculation 202 is a means for calculating the tilt in the character arrangement direction. This process
For example, as shown in FIG. 2D, a center point 211 of a quadrangle 205 indicating a plurality of character areas is obtained, and the x-coordinate between the center points of other quadrangle 205 closest to the center points and the x-coordinate. The difference b between the difference a and the y coordinate is calculated, and the average value of all the differences a and b is calculated, and the values of the average difference a and the average difference b are stored in the register.

The image rearrangement 203 is means for horizontally correcting the line direction of the characters of the image information. In this process, for example, the coordinate conversion calculation is performed on all pixels by using the storage address of each pixel information in the memory as the correction coefficient with the average difference a and the average difference b obtained by the tilt angle calculation unit 202. The image information 212 after the tilt angle correction as shown in 2 (e) is obtained. The above calculation can be realized by a logic circuit.

Next, FIG. 3A shows the image synthesizing section 4 of FIG.
The processing of No. 03 is shown. Partial image reduction unit 501
Is to reduce the read partial image information so as to match the character size of the entire image captured in advance. Specifically, the distance K between the original and the video camera when reading the entire image and the distance M between the original and the video camera when reading the partial image are measured, and the partial image is reduced by M / K times. Will be realized in. The reduction processing can be realized by the same logic circuit as the reduction processing in the size conversion 108 in FIG.

FIG. 3B shows the read partial image information 504.
3D is the whole image information 507 captured in advance.
Indicates. FIG. 3C shows reduced image information 505 of a partial image obtained by reducing the size of the character information in the partial image information 504 so as to match the size of the character information in the whole image information 507.

The whole-image matching area detection unit 502 is a means for detecting which area of the whole image the reduced partial image information 505 matches. As a method of determining the coincidence of the character areas, for example, the coordinates of the change position of the gradation in pixel units in the main scanning direction and the sub scanning direction are detected, and the relative distance values of the plurality of change position coordinates are compared with that of the entire image. If the sum of the difference amounts is smaller than the determination threshold value, it is determined that they match. These functions can be realized by a logic circuit. By the above processing, the partial image information 50 of FIG.
5 is the upper left area 50 of the whole image information 507 of FIG.
A match of 6 is detected.

When it is detected that the partial image to be image-synthesized has a matching area with the image in the whole image memory 402, the image synthesizing unit 503 and the partial image are already in the whole image. This is means for synthesizing adjacent partial images whose position coordinates have been detected and newly storing them in the synthetic image memory. Specifically, the storage address of the partial image is converted into the address of the composite image memory to store the image data. Address conversion can be realized by a logic circuit.

[0038]

As described above, the inclination of the reading scan is detected and corrected from the image information read by the video camera, and the matching area is detected from the read image information to synthesize the image.
A small and lightweight scanner can read and synthesize image information of a document of an arbitrary size without requiring an auxiliary member other than the scanner.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of the present invention.

FIG. 2 is a block diagram of an angle correction unit 105.

FIG. 3 is a block diagram of an image composition unit 403.

[Explanation of symbols]

101 ... Original, 103 ... Image reading section, 104 ... Partial image memory, 105 ... Angle correction section, 107 ... Synthetic image memory, 108 ... Size conversion section, 109 ... Image display section, 11
0 ... Portable information terminal, 201 ... Character area detection unit, 202
... inclination detection unit, 203 ... pixel rearrangement unit, 204 ... image information read by being inclined, 205 ... character detection region, 206 ... upper end portion, 207 ... lower end portion, 208 ... left end portion, 209 ... right end portion, 210 ... inclination Angle detection operation, 211 ... Center point, 21
2 ... Image information after angle correction, 401 ... Video camera, 4
02 ... Whole image memory, 403 ... Image combining section, 501 ...
Partial image reduction unit, 502 ... Matching area detection unit in entire image,
503 ... Image synthesizing unit, 504 ... Partial image information, 505 ...
Reduced image information of partial image, 506 ... Partial image matching area in whole image, 507 ... Whole image information.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location H04N 1/387 5/225 Z

Claims (6)

[Claims] 1. A two-dimensional image reading means, a correction means for correcting a scanning angle of an image read by the two-dimensional image reading means, and a storage means for storing an angle-corrected entire image.
Storage means for storing the angle-corrected partial image, combining means for the partial images, storage means for storing the combined image, size converting means for converting each of the image information into an arbitrary size, and each of the image information. And an image input device comprising display means for displaying the image information stored in each storage means in an arbitrary size. 2. A combination means for reading a whole image and a partial image obtained by dividing the whole image into a plurality of parts, and combining the partial images into one image based on position information of each partial image based on the whole image information. The image input device described. 3. The image input device according to claim 1, wherein the display unit is a display unit that is displayed after being converted into a size that fits in an image display unit based on image information. 4. The display means is capable of distinguishing between the read partial image area and the non-read image area when the entire image is displayed on the image display section. The image input device according to claim 1. 5. The image input device according to claim 4, wherein the display means is a liquid crystal display device. 6. The image input device according to claim 1, wherein the two-dimensional image reading means is a video camera.