JPH0575799A - Scanner - Google Patents

Abstract

PURPOSE:To attain high speed reading of a rectangular area by moving a line image sensor in the subscanning direction at a reading speed in the rectangular area and at a high speed at the outside of the area when the rectangular area being part in one page of an original is read. CONSTITUTION:A CPU 7 receives an upper left point 11a of a read area 11 and a dot number in the subscanning direction of a read area 11 from a host machine and writes them to an area detection circuit 5. Then the upper left point 11a, dot numbers C, F from upper and left end on an original 10 and a dot number D in the subscanning direction of the area 11 are recognized by the CPU 7. When the original scanning is started, the CPU 7 moves a line image sensor 1 in the subscanning direction at a high speed at the positions C, F. Furthermore, the sensor 1 is moved for a period with respect to a one-line read time of the sensor 1 at the position D. On the other hand, a memory controller 6 allows the operation of a conversion circuit 3 from the read start point and writes the parallel picture data to an image memory 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a workstation,
The present invention relates to a scanner device which is one of input devices such as desktop publishing (hereinafter referred to as DTP) and personal computer.

[0002]

2. Description of the Related Art In recent years, with the widespread use of tools such as workstations, DTPs, and personal computers, OA is advancing, and there is a growing demand for higher efficiency and shorter processing time for character / graphic / image data processing. It has become to. Among them, a scanner device is used as a means for inputting image data to the OA device, but even if a manuscript needs to be read in order to process a rectangular area of one page, the entire one page is read. It took the same time as the case and the processing speed was slow.

[0003]

As described above, in the conventional method, the moving speed of the original in the sub-scanning direction by the image sensor is the same in the reading rectangular area within one page and the other areas, and Also, when it is desired to read an arbitrary rectangular area (smaller than the document size) in one page, it takes the same time as reading the entire one page, and there is a problem that the processing speed is slow.

The present invention solves such a problem, and an object thereof is to enable high-speed reading of a read rectangular area.

[0005]

In order to solve this problem, according to the present invention, a line image sensor scans a document in units of one horizontal line sequentially in the sub-scanning direction to read image data, and a scanner device for reading image data scans the read document surface. A light source for illuminating, a line image sensor for photoelectrically converting an optical signal reflected from the document surface for each horizontal line, and a binarizing circuit for converting an analog signal of the line image sensor output into binary digital data, A reading rectangular area reference point within one page of the original, a means for detecting the number of dots in the sub-scanning direction from the original reference point, and a number of dots in the reading rectangular area in the sub-scanning direction, and a feed cycle of the line image sensor in the sub-scanning direction are set. And a means for changing the movement of the line image sensor in the sub-scanning direction of the line image sensor only within the reading rectangular area. Done in viewing takes speed, outside the region are those to perform at a high speed.

[0006]

According to the present invention, with the above-described structure, when a part of a rectangular area in one page of a document is read, the movement of the line image sensor in the sub-scanning direction is controlled by the reading speed of the line image sensor only in the reading rectangular area. The high-speed reading of the read rectangular area can be performed by performing the operation at a high speed outside the area.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall block diagram of an apparatus according to an embodiment of the present invention.

In this embodiment, as shown in FIG. 2, the original 10 is A4, the line image sensor is a contact image sensor, and the A4 horizontal size line image sensor is moved in the sub-scanning direction (arrow X direction in FIG. 2). However, the image data is read line by line. C for line image sensor
In the case of a reduction optical system such as a CD, the mirror that transmits the reflected light from the document to the line image sensor moves. Further, the reading area 11 indicated by hatching is assumed to be instructed by a host machine such as a personal computer or a workstation.

In FIG. 1, reference numeral 1 denotes a line image sensor for photoelectrically converting an optical signal read by scanning an original for each horizontal line, and 2 for converting an analog signal output from the line image sensor into binary digital data. A binarization circuit, 3 is a conversion circuit for converting the binary data output from the binarization circuit 2 from serial data to parallel data (for example, parallel data is 16 bits), and 4 is the parallel data stored therein. The image memory 5 includes dot numbers (distances) C and F from the upper left point 11a of the reading area 11, the upper edge of the original 10 and the left edge of the original 10 and the number of dots in the sub-scanning direction of the reading area 11 shown in FIG. An area detection circuit for detecting D, 6 is a memory for writing only the image data in the reading area 11 from the values of C, F and D to the image memory 4. The controller 7 receives the upper left point 11a (starting position) of the reading area 11 from the host machine, outputs it to the area detecting circuit 5, and controls the movement of the line image sensor 1 in the sub-scanning direction (microcomputer). Reference numeral 8 denotes a motor drive circuit that moves the line image sensor 1 in the sub-scanning direction according to an instruction from the CPU 7, and 9 denotes a motor that moves the line image sensor 1 in the sub-scanning direction. Although not shown in the drawing, a light source for illuminating the document surface is provided.

The operation of the above configuration will be described below.
In FIG. 1, the CPU 7 first receives from the host machine the upper left point 11a of the reading area 11 and the number of dots in the sub-scanning direction of the reading area 11 shown in FIG.
Write in. Then, the scanner recognizes the dot numbers (distances) C and F from the upper left point 11a of the reading area 11, the upper edge of the original 10 and the left edge of the original 10, and the number of dots D in the sub-scanning direction of the reading area 11. To be done. After that, the document scanning is started. However, as shown in FIG. 2, since the positions C and D are not in the reading area, the CPU 7 moves the line image sensor 1 at high speed in the sub-scanning direction. The line image sensor 1 is moved at a period (low speed) of the line image sensor 1 at the position D. On the other hand, the memory controller 6 reads the reading start point (upper left point 11 of the reading area 11).
The operation of the conversion circuit 3 is permitted from a), and parallel image data (for example, 16-bit unit) is written in the image memory 4. By the above operation, 1
It is possible to read binary image data of a rectangular area of a copy at high speed.

[0011]

As described above, according to the present invention, a light source for illuminating the surface of a reading original, a line image sensor for photoelectrically converting an optical signal reflected from the original surface for each horizontal line, and the line image sensor. Output analog signal 2
A binarization circuit for converting the value into digital data, and detecting the reference point of the reading rectangular area within one page of the original, the number of dots in the sub-scanning direction from the original reference point, and the number of dots in the reading rectangular area in the sub-scanning direction. And a means for varying the feed cycle of the line image sensor in the sub-scanning direction, and the movement of the line image sensor in the sub-scanning direction is performed at the reading speed (low speed) of the line image sensor only within the reading rectangular area. By performing the scanning at a high speed outside the area, a scanner device capable of high-speed reading can be realized.

[Brief description of drawings]

FIG. 1 is an overall block diagram of a device according to an embodiment of the present invention.

FIG. 2 is a reading area diagram for a document A4 read according to the present embodiment.

[Explanation of symbols]

 1 image sensor 2 binarization circuit 3 conversion circuit 4 image memory 5 area detection circuit 6 memory controller 7 CPU 8 motor drive circuit 9 motor 10 original 11 reading area 11a upper left point

Claims (1)

[Claims] 1. A scanner device for scanning a document in the sub-scanning direction in units of one horizontal line by a line image sensor to read image data, a light source illuminating the surface of the document to be read, and a light signal reflected from the surface of the document. From a line image sensor that performs photoelectric conversion for each horizontal line, a binarization circuit that converts an analog signal of the line image sensor output into binary digital data, a reading rectangular area reference point and an original reference point within one page of an original. And a means for detecting the number of dots in the sub-scanning direction of the reading rectangular area and a means for varying the feed cycle of the line image sensor in the sub-scanning direction. Is moved at the reading speed of the line image sensor only within the reading rectangular area, and at high speed outside the area. Scanner device.