JPH04249476A - Picture data compressing device - Google Patents

Abstract

PURPOSE:To compress a picture data by converting the data of a 2nd address of a consecutive dot pattern into a consecutive number data counted by a counting means and identifying and storing a converted and a non-converted dot pattern. CONSTITUTION:A keyboard 23 is operated to retrieve an electronic file 27 with a retrieval key for an account number or the like, the picture data of a desired seal stamp is called and stored in a memory 23. Then according to the bit map data of the picture data, a CPU 22 decodes the data of a dot pattern replaced into 4-bit into 8-bit data. Then the CPU 22 gives the data of the decoded dot pattern and the original 8-bit dot pattern data altogether to a monitor 24 as a picture data, on which the picture of a seal stamp is displayed. Thus, the stored picture data is compressed to nearly 33% with respect to the original picture data.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image data compression device useful for electronically storing image data.

0002

2. Description of the Related Art It has been widely practiced in the past to store images by electronic means, such as by registering image data with a computer equipped with an image scanner or the like. For example, in a financial institution, an image of a depositor's seal is stored in advance, and the image of the seal stamped on a deposit withdrawal request form is displayed on a monitor by recalling the stored image of the depositor's seal. This is done to save labor in the seal verification process.

0003

[Problem to be Solved by the Invention] However, the amount of such image data is generally larger than normal data such as key input data, and therefore the number of items that can be registered is limited. There was a problem in that it took a long time to transmit data.

The present invention has been made in view of the above-mentioned problems, and it is possible to increase the number of image data that can be stored within a certain capacity by compressing read image data in image data processing. An object of the present invention is to provide an image data compression device that can shorten image data transmission time.

[0005]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the image data compression apparatus of the present invention includes a binarizing means for binarizing image data sent from an imaging means for capturing an image;
dividing means for dividing binarized image data into a group of dot patterns having a first number of bits; a conversion means for converting into a conversion code having a second number of bits smaller than the number of bits, a counting means for counting the number of consecutive identical dot patterns in the address order among the dot pattern group, and the consecutive dots. means for converting the data at the second address of the pattern into consecutive number data counted by the counting means and deleting the data at the third and subsequent addresses; and converting the converted dot pattern and the unconverted dots. It is composed of a pattern and a storage means for identifying and storing the pattern.

[0006]

[Operation] According to the present invention, the image data for the image taken by the imaging means is first binarized by the binarization means,
The binarized image data is divided into dot pattern groups of a first number of bits. Next, the frequently appearing dot pattern is converted and compressed into a conversion code having a second number of bits smaller than the first number of bits. In addition, when the same dot patterns are consecutive in the order of addresses among the dot pattern group, the data of the second address of the consecutive dot patterns is converted to the data of the consecutive number counted by the counting means. , and the data at the third and subsequent addresses will be deleted. Then, the converted dot patterns and unconverted dot patterns are identified and stored by the storage means.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings, taking as an example the case where an image of a seal is stored.

FIG. 1 is a block diagram of an image data compression device according to an embodiment of the present invention, FIG. 2 is a flowchart explaining the procedure of image data compression in the image data compression device of FIG. 1, and FIG. 3 is a diagram of the image data compression device of FIG. A data explanatory diagram illustrating the procedure of image data compression in the compression device. FIG. 4 is an explanatory diagram of the conversion of consecutive number data in the procedure of image data compression in the image data compression device of FIG. 1. FIG. 5 is a diagram illustrating the conversion of consecutive number data FIG. 2 is an explanatory diagram of a data structure of image data to be processed.

In FIG. 1, reference numeral 1 denotes a CCD camera (imaging means) placed at a position to take an image of the stamp of the document D placed on the upper surface of the glass plate 4, and 2 compresses the data of the taken image of the seal. an image data compression device 3 for processing an image of a seal on a document D placed on a glass plate 4;
It is a mirror placed in a position to project the image.

The image data compression device 2 includes an A/D converter 21 as a binarization means for binarizing the signal of the image data of the seal imaged by the imaging means 1, and an A/D converter 2.
A CPU 22 that processes image data signals from 1, and a CPU 22 that processes image data signals from
It is composed of a memory 23 as a storage means for storing procedures executed by the U 22, compressed image data, etc., a monitor 24 for displaying images, an input/output interface 25, a keyboard 26 for external input, and the like. In the memory 23,
An image data dividing means, a counting means, a converting means, which will be described later.
Conversion code setting means and the like are stored.

The original D on which the seal has been stamped is illuminated by illumination means (not shown), and the image of the illuminated seal on the original D is projected onto the image pickup means 1 by the mirror 3, and is imaged by the image pickup means 1.

Next, the image compression procedure using the image data compression apparatus 2 of this embodiment will be explained using FIGS. 2 to 4. 2, 3, and 4 are diagrams for explaining the procedure of image data compression in the image data compression apparatus of FIG. 1.

The image data signal (
3(a)) is binarized by the A/D converter 21 (FIG. 3(b)), and sent to the CPU 22 via the input/output interface 25. Then, the binarized signal is inverted (FIG. 3(c)), and the handwritten part of the seal becomes 1 and the blank part becomes 0. Then, using the dividing means stored in the memory 23, the inverted image data is divided in the horizontal direction in FIG. )), memory 23
The information is sequentially stored and stored at a predetermined address in the data area (FIG. 3(e)). For convenience of explanation, 000000
00 is converted to a certain code, such as 00H, 11111111 to FFH, etc.

When all of one image data has been stored in the data area of the memory 23, a conversion code is set and the extraction means stored in the memory 23 extracts the dot pattern from the data. Only 16 frequently occurring dot patterns are extracted. Then, the conversion code setting means sets a different 4-bit conversion code for each of these 16 dot patterns. For example, by replacing 00111000 with 0001, 8-bit data becomes 4-bit data.

Next, the stored dot pattern data is called up again, and the counting means is used to count the number of consecutive identical dot patterns stored. Then, as shown in FIG. 4, the data at the second address of the continuous dot pattern is converted into a conversion code using the consecutive number counted by the counting means, and the data at the third and subsequent addresses is converted into a conversion code using the consecutive number counted by the counting means. Delete. Figure 3(a)
As shown in the figure, in normal image data, dot patterns consisting of all white dots (00H), all black dot patterns (FFH), etc. frequently appear. However, if the data is compressed as described above, even if the same dot pattern is consecutive, only two addresses are required.

After the image data has been compressed as described above, it is determined whether the dot pattern has been given a conversion code or not, and the data is stored in the memory 23. For example, if a dot pattern is assigned a conversion code, "1" is assigned as bitmap data to the dot pattern at that address, and if no conversion code is assigned, the dot pattern is "0" is assigned as the bitmap data for.

FIG. 5 is an explanatory diagram of the data structure of image data finally stored in the memory. As described above, when the inquiry of one image data stored in the data area, the conversion to the necessary conversion code, and the addition of bitmap data are completed, these data are rearranged and stored in the memory 23. Store it back in the data area. In order to speed up later readout, this sorting method stores bitmap data, replaced dot pattern data, and unreplaced dot pattern data in this order, as shown in FIG. For example, bitmap data in the horizontal direction (one line) of image data is grouped together and stored in one address. A piece of compressed image data organized into such a data structure is transferred from the data area of the memory 23 to an external large-capacity electronic file 2.
7 (FIG. 1) and stored. Then, the next image is captured by the imaging means 1, and the image is similarly compressed and stored.

Next, a procedure for reading the image data of a seal stamp compressed and stored in the data structure as described above and displaying it on a monitor for inquiry will be explained.

First, operate the keyboard 26 to search for the electronic file 27 using search keys such as the account number of the deposit account.
The image data of the desired seal is retrieved and stored in the memory 23. Then, according to the bitmap data of the image data, the CPU 22 restores the dot pattern data replaced with 4 bits to 8 bits. Then, the CPU 22 combines the restored dot pattern data and the dot pattern data originally stored in 8 bits and outputs it to the monitor 2 as image data.
4 to display the image of the seal.

In the above embodiments, 8 bits were used as the first number of bits and 4 bits was used as the second number of bits, but the first number of bits could be set to 16 and the second number of bits to 8. , of course, may be changed as appropriate depending on the ability of the CPU 22.

According to the image compression apparatus of the above embodiment, the stored image data can be compressed to about 33% of the original data amount.

[0022]

Effects of the Invention As explained above, according to the image compression device of the present invention, it is possible to dramatically compress image data, so a large number of image data can be stored in a storage means with a limited capacity. In addition, the data transmission time for calling and displaying can be dramatically shortened.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of an image data compression device according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating the procedure of image data compression in the image data compression apparatus of FIG. 1;

FIG. 3 is a data explanatory diagram illustrating a procedure of image data compression in the image data compression device of FIG. 1;

4 is an explanatory diagram of conversion of consecutive number data in the image data compression procedure in the image data compression device of FIG. 1; FIG.

FIG. 5 is an explanatory diagram of the data structure of image data stored in a memory.

[Explanation of symbols]

1: Imaging means 2: Image data compression device 21: A/D converter (binarization means) 22: CPU 23: Memory

Claims (1)

[Claims] 1. A binarizing means for binarizing image data sent from an imaging means for capturing an image; and a dividing means for dividing the binarized image data into groups of dot patterns each having a first number of bits. , among the dot patterns of the first number of bits,
a conversion means for converting a specific dot pattern that frequently appears into a conversion code having a second number of bits smaller than the first number of bits; A counting means for counting the number of consecutive dots, converting the data of the second address of the continuous dot pattern into the data of the consecutive number counted by the counting means, and deleting the data of the third and subsequent addresses. 1. An image data compression device comprising: means for converting dot patterns; and storage means for identifying and storing converted dot patterns and unconverted dot patterns.