JPH0378775A - digital copy machine - Google Patents

Abstract

PURPOSE:To perform edition with a minimized memory capacity by allowing a graphic picture of binarization picture data to carry out vectrization and using the stored picture subjected to drawing operation s output picture data. CONSTITUTION:An original reading means 1 reads optically an original to obtain binarization picture data, a first storing means 2 stores the picture data obtained by the original reading means 1, and a vector making means 4 allows the graphic picture of the picture data stored in the first storing means 2 to carry out vectorization. A second storing means 7 stores the data made into a vector by the vectorization means 4, and a plotting means 8 develops the data read out of the second storing means 7 in a third storing means 9. An output means 10 forms an image on transfer paper through the use of data read out of the third storing means 9. Thus edition can be carried out with a minimized memory capacity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a digital copying machine that digitally processes image information and copies it.

[Conventional technology]

2. Description of the Related Art Conventionally, as an image forming apparatus, there is an electronic copying apparatus that employs a process in which an optical system reads a document and simultaneously exposes a photoreceptor to light, and sequentially performs development, transfer, and fixing. With this type of copying device, the copied image has the same content as the original, and the copied image is not processed (edited) in any way.
The words of God have not been fulfilled.

However, there is a need for copying machines that can perform editing such as extracting, repositioning, compositing, and deleting images in order to handle a variety of document creation tasks in offices, and digital copying machines are needed to meet these demands. There is a copying machine.

A digital copying device takes in image information as a digital signal, and if editing is not required, outputs it as is as a signal for a printer.

On the other hand, when editing is required, a configuration is generally adopted in which a signal block corresponding to an image area required for editing is transferred to an image processor and stored in an image memory.

In addition, as related to this type of technology, for example, Japanese Patent Application Laid-Open No. 63-16762, Japanese Patent Application Laid-Open No. 63-16763,
There are JP-A-63-16764, JP-A-63-66679, and JP-A-64-53272.

[Problem to be solved by the invention]

However, in conventional digital copying machines, the memory capacity has increased, leading to an increase in the size and cost of the device.

SUMMARY OF THE INVENTION An object of the present invention is to provide a digital copying machine that can perform editing processing using a minimum memory capacity.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a document reading means for optically reading a document to obtain binarized image data, a first storage means for storing image data obtained by the means, and a first storage means for storing image data obtained by the means. vectorization means for vectorizing a graphic image of image data stored in the image data, a second storage means for storing data vectorized by the means, a third storage means, and reading from the second storage means. The apparatus is provided with an image forming means for developing the data read out from the third storage means, and an output means for forming an image on transfer paper using the data read from the third storage means.

In order to reduce memory capacity, the first storage means and the third storage means may be the same.

In order to make it possible to process originals containing not only figures but also characters, a line/character discriminator is provided for discriminating between character images and figure images from the image data stored in the first storage means. It is desirable to provide means for cutting out the data into the smallest unit and storing it in the second storage means, either as a bitmap or after compression processing.

Further, as a means for reducing the memory capacity, it is also possible to provide means for creating a binary compressed image using the drawing means for the data from the vectorizing means and restoring this image using the output means.

[Effect]

According to the above means, the graphic image of the binarized image data is subjected to vectorization processing, and the stored image subjected to drawing processing is used as output image data. In addition, character images are cut out using the minimum unit,
The image is compressed and saved. Therefore, in the case of documents that are mostly lines, such as documents and forms, the amount of data can be reduced by vectorizing them, and the memory capacity can therefore be reduced. Furthermore, character images can be efficiently saved by cutting out the minimum unit.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a digital copying machine according to the present invention, and FIG. 2 is a flowchart showing an example of processing according to the present invention.

A document reading section l (document reading means) is provided to read the document, and optically reads the contents of the document, converts it into binary digital data, and outputs it. The document reading section 1 has 2
A memory 2 (first storage means) for storing value digital data is connected, and a line/character discrimination section 3 is connected to this memory 2.

The line/character discrimination section 3 (line/character discrimination means) includes a vectorization processing section 4 (vectorization processing means) that performs vectorization processing corresponding to line figures, and a vectorization processing section 4 (vectorization processing means) that performs image compression processing corresponding to character images. An image compression processing unit 5 is connected thereto.

A memory 7 (second storage means) is provided to store the processing results of the vectorization processing section 4 and the image compression processing section 5, and a write/read control section 6 that writes and reads data to and from the memory 7. It is connected to the vectorization processing section 4 and the image compression processing section 5.

The writing/reading control section 6 is connected to a drawing processing section 8 (drawing means) that develops vector data or character image data as an output image in the memory 9 (third storage means). Furthermore, the drawing processing section 8 includes an output section 10 (
output means) is connected, and a printer 11 is connected to this output unit 10.
is connected.

Next, the operation of the embodiment with the above configuration will be explained with reference to FIG.

First, by placing a document containing a mixture of lines and characters as shown in Figure 3 on the document table (not shown) installed on the top of the digital copying machine and pressing the copy start button (not shown), the document can be copied. is optically read by the document reading unit 1 (
In step 21), the data is converted into binary digital data and output. This binary digital data is stored in the memory 2 as input image data.

Next, the input image data stored in the memory 2 is read out by the line/character discriminator 3, which traces the outline of a set of connected black pixels in the image, and determines the minimum of the outline in the scanning direction and the sub-scanning direction. Find value and length. This becomes the smallest rectangle surrounding the black pixel set. Based on the size of the outline, it is determined whether the black pixel set in the input image data is a character image or a line figure image, and if it is a line figure, the image data is output to the vectorization processing unit 4, outputs the image data to the image compression processing section 5 (step 22).

The vectorization processing unit 4 vectorizes the line figure (step 23), and further performs vector correction in the direction where the angular error between the vector direction and the preset alignment direction is small (
Step 24). In the case of a character image, the smallest rectangular image is cut out by the line/character discrimination section 3, and output as is or after being compressed by the image compression processing section 5 together with the starting position data (step 29).

The image data output from the vectorization processing section 4 or the image compression processing section 5 is stored in the memory 7 via the write/read control section 6 (step 25). With the above steps, reading and storing the original is completed.

When outputting the stored manuscript, the write/read control unit 6 reads image data (vector data or character image data) from the memory 7 (step 26).
, the vector data or character image data is expanded into the memory 9 as output image data by the drawing processing unit 8 (step 27).

The data stored in the memory 9 is read out by the output section 10 and applied to the printer 11 for printing (step 28). The output result of this print is the 4th
As shown in the figure, the handwritten line diagram is processed into a straight line.

Next, the contour tracing process and image determination process by the line/character discrimination section 3 will be described in detail.

First, the input image is scanned to find a black pixel to start tracking. Next, contour pixels are traced counterclockwise from the tracing start pixel in the case of an outer contour line, and clockwise in the case of an inner contour line. Then, when the pixel returns to the tracing start pixel again, the tracing of the outline of one black pixel set ends. The above operations are repeated until there are no untracked contour pixels.

Figure 7 shows an example of tracing the outline of one black pixel set, and the direction of the outline is 0 to 7 as shown in Figure 8.
The direction is as follows.

First, as shown in pointillism 30 in FIG. 7, the tracking start pixel is searched by rask scanning. For example, if the tracking start pixel is (i + j, j)
If it is found at the position, it is determined that the previous pixel during rask scanning is a white pixel and is an outer contour line, and tracking is started counterclockwise from this position. Next, in Figure 8, “
Neighboring pixels are checked counterclockwise from the direction 4'', and the direction of the first black pixel found is set as the direction of the outline. Next, the tracking center pixel is moved to that black pixel, and neighboring pixels are checked counterclockwise from the direction of the previous contour 0 line (direction "2" in FIG. 8), and this is repeated until the tracking start pixel is reached. By performing such processing, a contour line 31 as shown by the arrow group in FIG. 7 is obtained.

Of the tracing results, only the outer contour tracing is stored in the memory as contour data. As shown in FIG. 9, the contour data is composed of the starting position (minimum value) and length (maximum value - minimum value) obtained by taking the minimum and maximum values of the contour coordinates. The first line of FIG. 9 shows the contour tracing results of FIG. 7.

Next, an image determination method will be explained.

Based on the size of the contour data obtained as a result of contour tracing in the X and Y directions (see Figure 9), it is possible to determine whether it is image noise, characters, or figures inside the contour. judge. Determine the upper limit of the noise image size and the upper limit of the character image size in advance, and set them respectively to Ll and L2.
In this case, image determination is performed according to the flowchart in FIG.

As shown in FIG. 10, if the lengths X and Y are both smaller than Ll, it is regarded as noise (step 43), and if they are larger, the process moves to step 42 (step 41). In step 42, if the lengths X and Y are both greater than Ll and both the lengths X and Y are smaller than L2, the image is determined to be a character image (step 44), and the others are determined to be graphic images (step 45).

This image determination data is encoded as shown in FIG. 11 and registered in the order shown in FIG.

Here, unless the above-mentioned LL and L2 are changed in accordance with the magnification ratio R, accurate image judgment cannot be performed during variable magnification reading, so the following calculation is performed.

Ll' = LIXR L2' = L2XR Then, these Ll' and L2' are Ll at the time of judgment.

Used in place of L2.

Next, the processing executed by the vectorization processing section 4 will be described in detail.

The vectorization process of a binary line drawing image, which is one of the vectorization processing units 4, is described in, for example, IEICE Paper 1 2 Bungo, April 1985, VOL, J68-D, &4゜8
Pages 45 to 852, or JP-A-62-286177
As described in this issue, a method is used in which the center line is determined while tracing the contour lines on both sides of a line graphic image, and this is approximated as a polygonal line vector.

By the way, the process of combining and outputting a read image with a stored image is a process in which the output unit 10 generates a copy paper by ORing the input image signal read by the document reading unit 1 and the output image signal read from the memory 9. This can be achieved by visualizing it. For example, for a stored image as shown in Figure 4,
When originals as shown in FIG. 5 are combined, an output image as shown in FIG. 6 can be obtained.

When executing the functions of the present invention, by specifying the execution area in advance with a tablet or marker, a part of the document can be saved, or a line image or character image determined by the line/character discrimination section 3 can be saved. It is also possible to save only one.

Incidentally, in a device configured using semiconductor devices, the more functions the device has, the larger the memory capacity becomes, and in order to reduce costs and size, it is desirable to reduce the amount of memory.

Therefore, the first possible method is to
This is to input the data in a reduced size, and then enlarge it and output it after processing. With this method, the number of calculations in the process from input to output is also reduced, so the processing time is also shortened.

The second method is to compress the image data after reading the original, and to output the data after decompressing it after the compression process. Although it is possible to use the MH method used in facsimiles, etc., this compression and restoration method is possible, but since the necessary information is only from black pixels, it is possible to perform compression using black pixel run non-breathing (drawing processing unit 8) and restoration (performed by the output unit 10) will be described.

In this case, the data structure is as shown in FIGS. 12 and 13.
It consists of data on a start position and an end position in the scanning direction, and the data is registered in the order of rask scanning. Since the input image has a compressed data structure, the above contour tracing method cannot be used, and the following method is used. Here, explanation will be given with reference to FIG. 14.

■ Examine the compressed image data in order in the sub-scanning direction to find the starting point of an untracked black pixel.

(2) From there, search for an untracked black pixel starting point in the positive direction of Y (direction in which the number of sub-scanning lines increases).

■ If the black pixel ending point of the previous black pixel column in the same sub-scanning column is closer to the black pixel starting point of the next sub-scanning column in ■,
The process proceeds to the black pixel ending point of the previous black pixel column in the same sub-scanning column, and then searches for the black pixel ending point in the negative direction of Y from that point.

(2) If an untracked black pixel start point is not found, proceed to the black pixel end point of that black pixel column, and search for the black pixel end point in the negative direction of Y from there.

■ In ■ or ■, if the black pixel start point of the next black pixel column in the same sub-scanning column is closer than the black pixel end point of the next sub-scanning column, the next black pixel column in the same sub-scanning column Next, the black pixel starting point is searched in the positive direction of Y from that point.

■ When the above steps ■ to ■ are repeated and the trace returns to the tracing start point in ■, the tracing of one contour loop is completed. Then, return to ■ and search for the next tracking starting point.

■Repeat the steps from ■ to ■ above, and end the process when there are no black pixel starting points that have not been tracked yet.

Compared to the contour tracing method described above, the above method only needs to check the start and end points of black pixels, so the processing time is faster, and the black run length identification code is stored in the data structure shown in Figure 13. By filling in the identification flag above,
Memory for output images can be made unnecessary. Also,
Adjacent images can be separated accurately.

In the above embodiment, the memories 2 and 9 are provided separately, but they may be shared. Further, the memory 7 may be replaced with a semiconductor memory, and may be a large-capacity storage device such as a hard disk.

In this way, it becomes possible to store a large number of documents at the same time.

5 6 Further, processing such as scaling and rotation in units of 90° can be easily performed on stored data by coordinate transformation calculation. Furthermore, even if copy paper (transfer paper) of the same size and orientation as the stored original is not set, you can easily enlarge, reduce, and
You can obtain a drawing that has been rotated.

〔Effect of the invention〕

Since the present invention is configured as described above, it produces the effects described below.

In the digital copying machine according to claim 1, there is provided a document reading means for optically reading a document to obtain binarized image data; vectorization means for vectorizing a graphic image of image data; a second storage means for storing data vectorized by the means; a third storage means; and a vectorization means for storing data read from the second storage means. Since there is provided a drawing means for developing in the third storage means and an output means for forming an image on transfer paper using the data read from the third storage means, graphic (line drawing) originals such as documents and forms are provided. can be stored in memory with a small memory capacity.

In the digital copying machine according to the second aspect of the present invention, by making the first storage means and the third storage means the same, the memory capacity can be reduced.

The digital copying machine according to claim 3 further comprises line/character discriminating means for discriminating character images and graphic images from the image data stored in the first storage means, which cuts out the character image into minimum units and divides the character image into minimum units. Since a means is provided for storing the bitmap as it is or after compression processing in the second storage means, it is possible to process originals containing not only figures but also characters.

In the digital copying machine according to claim 4, there is provided means for creating a binary compressed image by the drawing means for the data from the vectorizing means and restoring this by the output means, so that the memory capacity can be reduced. It is possible to reduce deterioration of character images.

7 8

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a digital copying machine according to the present invention, FIG. 2 is a flowchart showing a processing example of the present invention, and FIG. 3 is an example of a document to be processed that includes a mixture of lines and characters. 4 is a front view showing the result of processing the original shown in FIG. 3 according to the present invention, FIG. 5 is a front view of the original to be synthesized with the stored image as shown in FIG. 4, and FIG. is an image diagram showing the result of combining the stored image in Figure 4 and the original image in Figure 5, Figure 7 is an explanatory diagram showing an example of tracing the outline of one black pixel set, and Figure 8 is Fig. 7 is an explanatory diagram showing the direction of the contour line in the example, Fig. 9 is a data diagram showing the contour data accompanying the tracking result, Fig. 10 is a flowchart showing the image judgment process, and Fig. 11 is the code of the image judgment data. FIG. 12 is a black pixel run length arrangement diagram showing an example of compression and decompression processing. FIG. 13 is a data structure diagram corresponding to the black pixel run length in FIG. 12. FIG. 14 is an explanatory diagram showing an example of outline tracing of a compressed image according to the present invention. 1... Original reading section, 2,7° 3... Line/character discrimination section, 4... Ring section, 5... Image compression processing section, Ring section, 10... Output section, 11. 9 ...Memory, -Vectorization processing 8...Drawing processing...Printer. 9 0 Seki------・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・・・・・・・

Claims (4)

[Claims] (1) A document reading device that optically reads a document to obtain binarized image data, a first storage device that stores the image data obtained by the device, and a graphic image of the image data stored in the device. a vectorization means for vectorizing, a second storage means for storing data vectorized by the means, a third storage means, and data read from the second storage means into the third storage means. A digital copying machine characterized by comprising: an image forming means for developing an image; and an output means for forming an image on transfer paper using data read from the third storage means. (2) The digital copying machine according to claim 1, wherein the first storage means and the third storage means are the same. (3) Line/character discrimination means for discriminating character images and graphic images from the image data stored in the first storage means is provided, and the character image is cut out into minimum units, and this is left as a bitmap or compressed. 2. A digital copying machine according to claim 1, wherein the digital copying machine performs processing and stores the processed data in said second storage means. (4) The digital copying machine according to claim 1, further comprising means for creating a binary compressed image by the drawing means for the data from the vectorizing means and restoring this by the output means. .