JP2697860B2 - Image processing device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an image processing apparatus for processing a document image.

2. Description of the Related Art There is known an apparatus which reads a document image with a CCD image sensor or the like and reproduces an image based on an image signal obtained thereby.

The main purpose of this device is to function as a conventional copier, but by electrically processing image signals,
This makes it possible to perform functions that were difficult with conventional copiers. For example, it is possible to easily perform editing such as image size conversion, extraction / deletion, and movement of an arbitrary image. For example, it is used in the field of design or the like to deform or modify characters.

[Problems to be solved by the invention]

In such an editing process, for example, it is possible to extract the outline of a black character and reproduce a white character, but the thickness of the outline is uniform.

[Means for solving the problem]

The present invention has been made in view of the above points, and provides an image processing apparatus that extracts an outline of an image from document image information and reproduces a rising portion and a falling portion of the extracted outline with different thicknesses. More specifically, a first contour extracting means for outputting contour data relating to a rising portion of a contour of an image by performing a first filtering process on the image data, and the first filtering process on the image data. A second contour extracting means for outputting contour data relating to a falling portion of the contour of the image by performing a different second filter process, wherein the rising portion and the falling portion of the image have different thicknesses. It is an object of the present invention to provide an image processing apparatus for outputting contour data for reproducing a contour.

〔Example〕

 Hereinafter, the present invention will be described using preferred embodiments.

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

In this embodiment, an image input device 11 for outputting 8-bit pixel data, a video data multiplexer 12 for determining a data input destination, a memory bank 0, a memory bank 1, a memory bank 2, a memory bank 3, An address multiplexer 17 for determining which address of the memory bank is to be stored, a contour processing circuit 18, a non-processing circuit 19 that does not perform contour processing, a CPU 110, and an operation unit 111
A selector 112, a printer 113, a communication line 114 through which data immediately before the line of interest passes, a communication line 115 through which data of the line of interest passes, and a communication line 116 through which data after the line of interest passes. Having.

The image input device 11 shines light on the image of the original on the platen,
This is a device that divides the image into pixels, which are the minimum units of an image, and sequentially reads each line using a light receiving element such as a CCD.

The image data is sequentially written to the memory banks 0, 1, 2, and 3 by one line of data by the video data multiplexer 12 and the address multiplexer 17. That is, first, one line of data is written to the memory banks 0, 1, and 2 respectively. When the writing to the memory bank 3 starts, the data of the memory banks 0, 1, and 2 is read, and the read data is read. The data is sent to the contour processing circuit 18 via the communication lines 114, 115, 116, and only the data of the line of interest is sent to the non-processing circuit 19.

When the writing to the memory bank 3 is completed and then the writing to the memory bank 0 is started, the memory banks 1, 2,.
3 is read out, the data from the memory bank 1 becomes the data of the previous line, the data of the memory bank 2 becomes the data of the target line, and the data of the memory bank 3 becomes the data of the next line. Become data.

The above operation is sequentially performed for all the lines using the four memory banks.

On the other hand, whether or not the contour processing is performed is determined by the input from the operation unit 111, and the contour processing circuit 1 is determined by the selector 112.
Either 8 or the output from the non-processing circuit 19 is selected and supplied to the printer 113. Then, the formed image is output from the printer.

The contour processing circuit 18 has two filters having different characteristics, and outputs contour information in which the thickness of the contour is changed between the rising part and the falling part of the image. That is, a process for obtaining a print as shown in FIG. 2A is performed for the input of the original image shown in FIG. 2B.

The above processing in one dimension is as follows. FIG. 3A shows the output of a light receiving element such as a CCD, and FIG. 3B shows the result of A / D conversion at each point of the output (1). Multiplying the value of (2) by a filter of (-1,0,1) yields (3), and further multiplying by a filter of α × (1,1,0, -1,1) yields (4) can get. When (4) takes a negative value to 0, and (3) and (4) are added, (5) is obtained.
Here, if the threshold value is set to 3 and (5) is binarized, (6) is obtained. The contour of the falling portion having the contour portion defined by 1 in (6) becomes thicker than the contour portion of the rising portion.

By executing this method on a two-dimensional plane (main scanning direction and sub-scanning direction), an output as shown in FIG. 2A is obtained. FIG. 4 is a block diagram of the contour processing circuit 18.

The three lines of data input from the video data multiplexer 12 are filtered by filters A54 and B55 with different characteristics.

In this embodiment, the filter A54 is Filter processing, and the filter B55 The following filtering process is performed.

FIGS. 5 (a) and 5 (b) show configuration examples of filters A54 and B55, respectively, for performing the above-described filter processing. 5 (a) and 5 (b), reference numerals 60 to 63, 71 to 77 denote adders, and 64 to 68, 78.
Numerals 90 are D flip-flops, and 69, 70, 91 to 93 are inverters.

The output 512 of the filter B55 is input to the condition circuit 56. The condition circuit 56 replaces the input having a negative value with zero and outputs it, and outputs the input having a positive value as it is. FIG. 6 shows an example of the configuration. Reference numeral 601 denotes an AND gate, and 602 denotes a selector. The selector 602 performs a select operation in accordance with MSB data indicating whether the image data is positive or negative. When the image data is positive, the input A is selected.

The output 513 of the condition circuit 56 and the output 511 of the filter A54 are added by the adder 57, and the addition result 514 is input to the comparator 58. Comparator 58 is the output 514 of adder 57
And a predetermined slice level 515, and a binary output 5 in which a value equal to or larger than the slice level 515 is set to 1 and a value smaller than the slice level 515 is set to 0.
16 is supplied to the selector 112.

By selecting the output 516 of the comparator 58 by the selector 112 and supplying it to the printer 113 as density information 517, a print output as shown in FIG. 2A is obtained.

It should be noted that the selector 112 has no processing information 514 or contour processing information 51.
3 is selected and output as density information 517. Here, the selection target can be changed for each pixel by the control signal 518 of the selector 112 from the CPU 110. Therefore, it is possible to select the output of the non-process information for a certain portion and the output of the contour processing information for a certain portion.

FIG. 7 is a block diagram showing a configuration in which the operator can freely set the density of the contour portion and other portions obtained by the contour processing circuit of FIG. Blocks having the same functions as those in FIG. 4 are denoted by the same reference numerals, and description thereof will be omitted.

By the AND gates 201 and 202, the OR gate 203 and the inverter 204, the density reproduction density 1 is output as the density information 205 for the outline portion and the density reproduction density 2 is output as the density information 205 for the other portions.

 FIG. 8 is a diagram showing an example of the operation unit.

In this figure, the editor operation unit 901 and the point pen 90
2. LCD display unit 903 for setting various modes, contour processing mode key 90, 4 paper selection key 905, AE and copy density adjustment key 906, copy number display 907, numeric keypad 908, clear key 909, copy start key 910 Is provided.

The setting of the outline processing mode by the operation unit in FIG. 8 will be described.

In the operation unit shown in FIG.
Is pressed, a display as shown in FIG. 9A is made on the liquid crystal display portion 903. In the display (A), when a key 701 is pressed, contour processing is performed on the entire area of the original image.
When 2 is pressed, contour processing is performed only on a desired area of the document image.

When the key 702 is pressed in the display (A), a display as shown in (B) is made on the liquid crystal display unit 903, and the mode becomes the area designation mode. During this display, the operator
By designating a point on the digitizer at 2, a desired area in which contour processing is to be performed can be designated.

When the area designation is completed, the liquid crystal display unit 903 can set the strength of the outline, which is displayed as shown in FIG. That is, when the key 703 is pressed in the display (C), the slice level for contour extraction becomes high, and the contour processing is weakened. When the key 704 is pressed, the contour processing is strengthened. Note that reference numeral 705 denotes a display indicating the set intensity, which moves left and right by operating the keys 703 and 704.

Next, the liquid crystal display unit 903 displays as shown in (D), and enters a setting mode of the density of the outline and the image density other than the outline. That is, the density is set by operating the keys 706, 707, 708, 709, respectively, and the display
And 711 move right and left.

When the copy start key 910 is pressed after the above settings, the contour processing according to the set mode is executed.

When the key 701 is pressed in the display (A),
The mode can be set in the same procedure as described above, except for the area designation by the display (B).

FIG. 10 is a block diagram of another embodiment of the contour processing circuit 18. As shown in FIG. In FIG. 10, the operator can select a plurality of filters by replacing the filter section with a ROM.

 The block diagram of FIG. 10 will be described.

Reference numerals 801 and 802 denote timing adjustment circuits which serve to send image data necessary for performing a filter process to the ROMs 804 and 805. It is mainly made of ratchet. A register 803 stores address data for determining which filter is to be selected. This data is sent from the CPU.

804 and 805 are ROMs that function as filters. 804 corresponds to the filter A54 shown in FIG. 4, and 805 corresponds to the filter B55 and the condition circuit 56 shown in FIG.

Outputs 806 and 807 from the filters correspond to outputs 511 and 513 in FIG. 4, respectively.

As described above, by executing the filter processing with the look-up of the table, the time required for the filter processing can be reduced, and the filter processing can be adapted to high-speed processing.

In this system configuration, if a plurality of types of filters are stored in the ROMs 804 and 805, the operator can select various types of filters. Therefore, an optimum output suitable for the document can be obtained. The filter selection method is the liquid crystal display
When entering the filter selection mode of the contour processing mode at 903, the number is displayed and the number is changed.

As described above, according to the contour processing according to the present embodiment, the contour of the document image is extracted and the thickness of the contour reproduced between the rising portion and the falling portion is made different. In a field or the like, it is possible to form a character with a change. In the present embodiment, the contour processing is performed two-dimensionally in the main and sub-scanning directions, but may be performed one-dimensionally in the main scanning direction as described in the principle. Executing the processing only in the direction can be easily realized by changing the filter coefficient.

(Effect)

As described above, the rising portion and the falling portion of the outline of the image can be reproduced with different thicknesses, so that desired outline processing can be executed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present process, FIGS. 2 (a) and 2 (b) are diagrams showing the process of the present invention, and FIG. 3 is a diagram when the present process is performed on a one-dimensional plane. Fig. 4 is a block diagram of the contour processing circuit, Figs. 5 (a) and 5 (b) are configuration diagrams of a filter circuit, Fig. 6 is a configuration diagram of a condition circuit, and Fig. 7 is other than the contour processing circuit. FIG. 8 is a diagram of an operation unit, FIG. 9 is a diagram of a display example of a display unit, FIG. 10 is a block diagram of contour processing, 11 is an image input device, 12 is a video data multiplexer,
17 is an address multiplexer, 18 is a contour processing circuit, 11
0 is a CPU and 113 is a printer.

Claims (1)

(57) [Claims] A first contour extracting means for outputting contour data relating to a rising edge of an image contour by performing a first filtering process on the image data; A second contour extracting means for outputting contour data relating to a falling portion of the contour of the image by performing the filter processing of (2), wherein a contour line having a different thickness between the rising portion and the falling portion of the image contour is provided. An image processing apparatus for outputting contour data to be reproduced by a computer.