JPH05252352A - Method and device for reading out image - Google Patents

Abstract

PURPOSE:To reduce the load of hardware and software for image processing and to improve a response speed. CONSTITUTION:An image signal obtained by picking up an original from its upper face is stored in a processing image circuit 7 and a preview image IF 12 inputs the image signal stored in the circuit 7 and outputs the inputted signal to a synthesizing circuit 13 as the bird's-eye view image of the original. An image overlay circuit 11 forms a frame line expressing a specified required display range based upon data relating to a display range outputted from a mouse calculating circuit 10 and outputs the formed frame line to the circuit 13, so that the frame line is displayed on a display part (not shown) connected to the output side of the circuit 13 being superposed on the bird's-eye view image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading method and an apparatus therefor, and more particularly, to an image reading method and an image reading method for reading an original image by scanning an image reading sensor on the original surface with the image surface exposed. Regarding the improvement of the device.

[0002]

2. Description of the Related Art As an image reading device, various types of devices have been proposed, for example, which read a document from the upper oblique direction without turning it over. In such an image reading apparatus, for example, as shown in FIG. 5, a reading unit 2 in which a tying optical system, a solid-state imaging device, and the like are housed in an upper part of a stand 1 is placed in a state in which the reading unit 2 can be swung vertically and horizontally. An image reading apparatus having an attached one has been proposed. In this image reading apparatus, the reading unit 1 is controlled by a control unit (not shown) so as to perform a so-called swinging operation, and the front surface of the document 3 (the front surface of the paper surface in FIG. 5) is scanned a plurality of times as illustrated. Then, the original image is read as a plurality of divided images. Then, the screens obtained by the divisional photographing are combined and displayed on a display device (not shown) as a screen (referred to as a preview screen) of the original 3 from the reading unit 1 (see FIG. 6A). )reference). After that, based on various data related to the document image obtained from this overhead view reproduction screen,
By performing the signal processing, the image that would be obtained when the original 3 was photographed from the front was displayed (FIG. 6).
(B)). Then, in the case of displaying only a desired portion of the front image, for example, a mouse known as a device for inputting position information on the screen is displayed on the front image shown in FIG. (Not shown) is used to specify the desired display range, and the specified range is
As shown in FIG. 6 (b), the one that is displayed at the same time on the screen on which the front image is displayed has been proposed.

[0003]

However, when the range is specified on the front image as described above, it is necessary to convert the entire image in the bird's-eye view state (FIG. 6A) into the front image. However, the process of converting the entire bird's eye view image into the front image puts a heavy burden on both hardware and software, and as a result, not only complicates the device, but also increases the response time and eventually the device. This has led to higher prices.

The present invention has been made in view of the above circumstances, and the front image finally displayed by specifying the range is a part of the preview image, and the entire preview screen is converted into the front image. It is an object of the present invention to provide an image reading method and an apparatus therefor which reduce the burden on hardware and software, paying attention to the fact that it is not necessary.

[0005]

In order to solve the above problems, an image apparatus according to a first aspect of the present invention is such that an image reading sensor disposed obliquely above a document is partially scanned with respect to the document surface a plurality of times. A first step of obtaining the image data of the original document as a set of a plurality of divided images, and the original document is exposed from the image reading sensor based on the divided image obtained in the first step. A second step of generating a bird's-eye view image at a time, a third step of displaying the bird's-eye view image obtained in the second step on a predetermined display device, and a step of displaying the bird's-eye view image by the third step. A fourth step of reading data regarding a desired range to be finally displayed as a front image in the bird's-eye view image, and a frame line indicating the desired display range input by the fourth step, which is the third step. Superimpose it on the bird's-eye view image displayed in the process 5, the sixth step of generating a front image based on the bird's-eye view image in the frame line superimposed and displayed on the bird's-eye image by the fifth step, and the sixth step. And a seventh step of displaying the front image on a predetermined display device.

In the image reading apparatus according to the second aspect of the present invention, a bird's-eye view image for generating a bird's-eye view image of the document by synthesizing a plurality of divided images obtained by scanning the document surface a plurality of times from above. In an image reading apparatus including a generation unit and a conversion unit configured to convert the bird's-eye view image generated by the bird's-eye view image generation unit into a front image, a range desired to be converted into a front image in the bird's-eye image Range information input means for inputting information, image superimposing means for superimposing a frame line indicating the range input by the range information input means on the overhead view image generated by the overhead view image generating means, and the overhead view image generating means Image selecting means for inputting the bird's-eye view image signal corresponding to the range specified by the range information input means to the converting means, from among the bird's-eye view images generated by It is intended to.

[0007]

In the image reading method according to the first aspect of the present invention, after the desired display range is designated on the bird's-eye view image, the bird's-eye view image in the designated display range is converted into the front image. By doing so, after converting the whole overhead view screen to a front image, a desired display range is specified on this front image, and compared with the conventional method of displaying the specified range again, Since only a small number of objects need to be converted, the burden on both software and hardware is lightened.

Further, in the image reading apparatus according to the second aspect of the present invention, since the display range desired as the front image is displayed on the bird's-eye image, the whole bird's-eye image is converted into the front image. Compared to the case where the range is specified by, the amount of data to be converted from the overhead image to the front image is small, and the circuit for conversion can be simplified and the amount of data is small. The advantage is that the response speed is improved.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image reading method and apparatus according to the present invention will be described below with reference to FIGS. Here, FIG. 1 is a schematic configuration diagram showing a configuration example of a main part of the image reading apparatus according to the present invention, and FIG. 2 is a more specific example of a portion A surrounded by a dashed line of the schematic configuration example shown in FIG. FIG. 3 is a flow chart showing the flow of the reading operation of the image reading apparatus according to the present invention, and FIG. 4 is a diagram showing the reading range designation in the image reading apparatus according to the present invention. It is explanatory drawing for explaining, Comprising: The figure (a) is an explanatory view showing the state where the bird's-eye view screen was displayed, and the figure (b) is the frame line used when designating a reading range is superimposed on the bird's-eye view screen. And FIG. 5 is an explanatory diagram for explaining the reading state by the reading unit common to both the image reading apparatus according to the present invention and the conventional image reading apparatus.

First, referring to FIGS. 1 and 2 for the image reading apparatus according to the present invention, the image reading apparatus according to the present invention is a bird's eye view image (FIG. 4A) displayed on a display unit (not shown). Mouse 4 for designating the desired display range of the front image, and a mouse I / F (abbreviation of interface circuit) for calculating the position on the screen designated by the mouse 4 from the output signal of the mouse 4. ) 5 and a bird's-eye view image based on the calculated value of this mouse I / F5 and a frame line a (portion indicated by a dashed line in FIG. 4B) to be superimposed and displayed on this screen. A range designating circuit 6 for synthesizing these, a processing image circuit 7 for accumulating the image data read by the reading unit 2 as a digital signal in a predetermined format, and an input instruction for designating a resolution, a reading start, and the like. Circuit 8 and this Luo range designation circuit 6, processed image circuit 7
And a main control circuit 9 for controlling the operation between the input instruction circuit 8 and
And are the main components. In addition, this Figure 1
In the configuration shown in (1), a part particularly related to the gist of the present invention is shown, and a general part of the image reading apparatus is omitted.

FIG. 2 shows one of more specific configurations of the portion A surrounded by the chain double-dashed line in FIG. That is, the part A surrounded by the two-dot chain line is
The present invention realizes a portion related to the gist of the present invention, in which a frame line indicating a range designated by the mouse 4 is displayed on the overhead image. That is, a mouse calculation circuit (the letters "circuit" is omitted in FIG. 2) 10 for calculating a specified range on the screen based on the output signal of the mouse 4 and a dashed line in FIG. A preview image I / which generates a bird's-eye view image as a preview image from the image overlay circuit 11 for generating the frame border i as described above and the image data of the processing image circuit 7.
F12, a synthesis circuit 13 for synthesizing the output signal of the image overlay circuit 11 and the output signal of the preview image I / F 12, and the mouse calculation described above based on the signal from the main control circuit 9 described above. And a sub control circuit 14 for controlling the circuit 10 and the like. Then, the output signal of the synthesizing circuit 13 is sent to a display unit (not shown), so that a screen as shown in FIG. 4B is displayed.

The operation of the present apparatus having such a configuration will be described generally. First, as shown in FIG.
The reading unit 1 attached to the top of the document reads the entire document as a preview image by partially scanning the document 3 over a plurality of regions, and the read image data of the document 3 composed of a plurality of so-called divided images. Are stored as digital image signals in the processed image circuit 7 shown in FIG. The image data stored in the processed image circuit 7
Data is input to the preview image I / F 12, and a bird's-eye view image (see FIG. 4A) is displayed by processing such as image combination. Then, the user operates the mouse 4 while looking at the bird's-eye view screen, and finally designates the range to be displayed as the front image, so that the frame line a generated by the image overlay circuit 11 is overlooked. It will be displayed superimposed on the screen (see FIG. 4B). Then, the bird's-eye view image within the range of the frame line A is converted into the front image and displayed on the display unit (not shown).

FIG. 3 is a flow chart showing a flow of a series of processes in the image reading apparatus.
The contents will be described below with reference to FIG. First, in step 100, resolution is designated. Specifically, the desired resolution is input by the user's operation in the input instruction circuit 8, and the reading of the original 3 is started at the same time when this resolution is designated (step 102).

Then, the reading unit 1 captures the entire image of the original 3 (a so-called "prescan" operation) (step 104). This whole image capturing is automatically performed, and at this time, the edge of the document 3 is detected (step 106). This edge detection is determined, for example, by detecting a difference in contrast between the original 3 and the surface on which the original 3 is placed (for example, the upper surface of a desk, a black sheet, etc.). Further, in this step 106, although not shown in FIG. 3, an image of the entire original 3 is viewed at the same time as the edge detection, that is, an overhead image is displayed. To display the overhead image, the divided images are input to the preview image I / F 12 from the processed image circuit 7 shown in FIG. 2, and the divided images are combined in the preview image I / F 12 to generate the overhead image. Is displayed. Then, by operating the mouse 4, the frame a is displayed so as to be superimposed on the bird's-eye view image (FIG. 4 (b)).
Further, by operating the mouse 4 to expand or reduce the frame line a to the range to be displayed as the front image, the range designation on the bird's-eye view image is completed. The generation of the frame line a by the mouse 4 and the superimposition on the bird's-eye view image are performed by the image overlay circuit 11 and the combining circuit 13.

In step 108, the size of the original 3 is calculated. This is so that focusing is performed (not shown in the flowchart) in a series of processing for the whole image capturing which is continuously performed from the step 102. The size of the original 3 is judged based on the distance and angle information between the read image of the original 3 and the reading unit 1 obtained as a result (for example, A4 or B5). Also, in step 110,
The inclination of the document 3 is detected. The inclination of the original 3 referred to here is, for example, when the original 3 is displayed on the screen as shown in FIG. 4A, the inclination of the original 3 with respect to the vertical direction of the screen (vertical direction in the drawing). Means still,
When it is known in advance that the original 3 is not tilted and the resolution does not matter, steps 110 and 112 described below are performed.
You may make it process step 114 directly, without performing. Further, when the size of the original 3 and the inclination of the original 3 are known in advance, steps 102 to 1
The step 112 described below may be executed without executing step 10.

In step 112, the zoom amount is calculated from the desired resolution previously set in the input instruction circuit 8 and the image of the original 3 captured at the present time,
A tying optical system (not shown) in the reading unit 1 is set. Then, the process proceeds to step 114 and the calculated original 3
The number of divisions when the original 3 is divided and scanned is calculated based on the size and the amount of zoom. In step 116,
Prior to starting the divisional scanning, necessary initialization is performed in software and hard disk. And step 118
In FIG. 5, the scanning unit 1 performs the divided scanning of the original 3 with the calculated division number, and after the scanning is completed, the process proceeds to step 120, and the gradation of the divided image is corrected.

In step 122, it is judged whether or not the images acquired by the division scanning are all background parts, that is, whether or not the entire surface is a uniform image, and if it is judged that the image is a uniform screen ( If YES is determined, the process proceeds to step 128, and if it is determined that they are not uniform (NO), the process proceeds to step 124. In step 124, distortion correction for geometrically correcting the distortion of the divided images caused by photographing the original 3 from diagonally above is performed. Then, the process proceeds to step 126, and the joining and combining of the divided images is performed until it is determined in step 128 that the joining process is completed. When the joining process ends, only the range previously designated by using the mouse 4 on the bird's-eye view screen is converted into the front image and displayed.

In this embodiment, the bird's eye view image is
The range that should be the front image can be specified, and the bird's-eye view images in the specified range are joined and combined to be converted into the front image. As compared with the case of designating a desired reading range and position on the front image of the entire document, the load of software and hardware can be reduced and the processing time can be shortened.

[0019]

As described above, according to the invention described in claim 1, the range desired to be displayed as the front image on the bird's-eye view image is designated, and then only this range is changed to the front image. Since the conversion is performed, the so-called hardware and software are compared to the case where the entire bird's-eye view image is once converted into a front image, and a range is specified on the front image to display the front image of the specified part. The burden on both sides is small, and significant effects such as improvement in processing speed and simplification of the configuration are achieved. Further, according to the invention of claim 2, a desired range to be displayed as a front image is designated on the bird's-eye image, and the bird's-eye image of the designated range is converted to the front image. By doing so, the amount of data to be converted from the bird's-eye image to the front image is less than that in the case where the entire bird's-eye image is once converted to the front image and the desired range of the converted front image is displayed again. Therefore, the remarkable effect that the apparatus can be simplified and the response speed can be improved is achieved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a configuration example of a main part of an image reading apparatus according to the present invention.

FIG. 2 is a schematic configuration diagram showing a more specific configuration example of a portion surrounded by an alternate long and short dash line in the schematic configuration example shown in FIG.

FIG. 3 is a flowchart showing a flow of reading operation of the image reading apparatus according to the present invention.

FIG. 4 is an explanatory diagram for explaining designation of a reading range and a position in the image reading apparatus according to the present invention, and FIG. 4A is an explanatory diagram showing a state in which a bird's eye view screen is displayed; FIG. 6B is an explanatory diagram showing a state in which the frame lines used when designating the reading range and the position are superimposed and displayed on the overhead view screen.

FIG. 5 is an explanatory diagram for explaining a reading state by a reading unit common to both the image reading apparatus according to the present invention and the conventional image reading apparatus.

6A and 6B are explanatory views for explaining designation of a conventional reading range and position, FIG. 6A is an explanatory view for explaining a state in which an overhead image is displayed, and FIG. It is an explanatory view for explaining a state where a frame line for designating a reading range and a position is displayed on a front image generated and displayed by a conversion process based on an overhead image.

[Explanation of symbols]

2 ... Reading unit, 4 ... Mouse, 10 ... Mouse calculation circuit, 11 ... Image overlay circuit, 12 ... Preview image I / F, 13 ... Compositing circuit

Claims (2)

[Claims] 1. Image data of the original document as a set of a plurality of divided images is obtained by partially scanning an original surface with an image reading sensor arranged obliquely above the original document. In the first step, the second step of generating a bird's-eye view image when the document is viewed from the image reading sensor based on the divided image obtained in the first step, and the second step. Data relating to a third step of displaying the obtained bird's-eye view image on a predetermined display device, and a desired range to be finally displayed as a front image among the bird's-eye view images displayed by the third step. And a fourth step of reading the
The fifth step of superimposing and displaying the frame line indicating the desired display range input in step 5 on the bird's-eye view image displayed in the third step, and the step of superimposing the frame line on the bird's-eye view image by the fifth step. It includes a sixth step of generating a front image based on the bird's-eye view image displayed within the frame, and a seventh step of displaying the front image generated by the sixth step on a predetermined display device. An image reading method characterized by the above. 2. An overhead image generating means for generating a bird's-eye image of the document by synthesizing a plurality of divided images obtained by scanning a document surface from a plurality of times, and a bird's-eye view image generating means. In an image reading apparatus including a conversion unit that converts a bird's-eye image into a front image, a range information input unit that inputs information regarding a range of the bird's-eye image desired to be converted into a front image, and the bird's-eye image generation. Image coverage means for superimposing a frame line indicating the range input by the range information input means on the bird's-eye view image generated by the means, and the range information input means of the bird's-eye view image generated by the bird's-eye view image generation means And an image selection unit for inputting the bird's-eye view image signal corresponding to the range specified by the above into the conversion unit.