JP2925300B2 - Optical character reader - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to an optical character reader for reading characters and the like written on a form and the like.

(Prior Art) In general, an optical character reader that reads characters and the like written on a form or the like processes a black-and-white (binary) image in which black is valid (character data) and white is invalid (background). It is targeted for. Therefore, in a scanning unit that performs optical scanning on a form or the like to detect an image, binarization corresponding to white / black is performed based on a certain threshold logic.
For this reason, OCR, which is the object of processing by the optical character reader,
The colors used for printing character entry frames, characters that do not need to be read, and the like on a form are colors that are determined to be white by an optical character reading device (threshold logic in the scanning unit), that is, dropout colors. The called color is used. This dropout color is determined according to the wavelength of the light source used in the scanning unit.

Therefore, in the case of an OCR form, unnecessary color printing of the background and the like is dropped out, and only the written characters (character data) to be read are detected and provided for character recognition processing.

By the way, in general, a lot of commercially available slips, forms that do not require processing by an optical character reader, and the like are used. For this reason, it is required that the characters and the like written on these slips and forms are read by an optical character reading device.

(Problems to be Solved by the Invention) However, commercially available slips, and slips or the like that do not assume the processing by the optical character reader (no dropout color is used) use various colors. Therefore, even when reading is performed by an optical character reading device, a character to be read is dropped out by binarization, or both the background and the character are determined to be black. For this reason, characters recorded on forms other than the OCR form cannot be read.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and provides an optical character reading device capable of reading characters of a form or the like that is not premised on processing by a commercially available general slip or optical character reading device. The purpose is to do.

[Constitution of the Invention] (Means for Solving the Problems) The present invention relates to a scanning unit for detecting a color image on a sheet on which characters and the like are written, and a storage unit for storing the color image detected by the scanning unit. Storage means, from the color image stored in the storage means, for each color, a label image detection means for detecting a label image consisting of a set of connected pixels, for the label image detected by the label image detection means, A label determining unit that determines whether or not the label image is a character label image, and changing only a label image determined as a character label image by the label determining unit to a specific color, and a color detected by the scanning unit. Display means for displaying an image; input means for inputting position information indicating an arbitrary position in the color image displayed by the display means; 2 by the label image determined as a character of the label image by storing the label determining unit label images and image indicated by the position information input by means as valid, and invalidates the other
And a character recognition processing means for performing a character recognition process based on the binary image obtained by the binarization means.

(Operation) According to such a configuration, the label image determined to be a character is displayed in a specific color indicating the character, and the determination can be corrected based on the displayed image.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a configuration of an optical character reading apparatus according to the embodiment. In FIG. 1, reference numeral 10 denotes a control unit which controls the overall operation of the apparatus. The following units are controlled by the control unit 10. In the figure, a scanning unit 20 scans a form or the like to be processed as a color image and outputs a color image signal to the sheet memory 30. The sheet memory 30 stores, for example, one form of the color image output from the scanning unit 20. In the figure
Reference numeral 40 denotes a labeling unit that labels a color image stored in the sheet memory 30 according to the connectivity of pixels for each color and stores the image (hereinafter, referred to as a label image). In the figure, reference numeral 50 denotes a label determination unit which determines whether or not the image labeled by the labeling unit 40 is a character. In the figure, reference numeral 55 denotes a character string extracting unit, which extracts a character string from the array of label images determined to be characters by the label determining unit 50. In the figure, reference numeral 60 denotes a display unit, which displays an image stored in the labeling unit 40 or the sheet memory 30 under the control of the control unit 10. In the figure, reference numeral 70 denotes an operation unit which can designate an arbitrary point in the image displayed on the display unit 60 and outputs position information indicating the designated position to the control unit 10. In the figure, reference numeral 80 denotes a binarization unit that validates a label image determined as a character by the label determination unit 50 or a label image indicated by position information from the operation unit 70 (black, for example, “1”); The binarization is performed with the others being invalid (white, for example, “0”), and the obtained binary image is output to the character recognition unit 90. The character recognition section 90 performs a character recognition process based on the binary image input from the binarization section 80.

 Next, the operation of the embodiment will be described.

First, a form to be processed is scanned by the scanning unit 20 and detected as a color image. The detected color image is stored in the sheet memory 30.

Next, the labeling unit 40 checks the connectivity of pixels for each of a plurality of colors in the color image stored in the sheet memory 30, performs labeling for each connected set, and performs image processing for each label (label image). Is stored. When the labeling is performed on the image for each color, the label determination unit 50 determines whether or not the image indicates a character based on, for example, the color and the connectivity of the label image of each color. As a method of character determination, a label image is fattened by a predetermined value, and when a continuous (lump) image is formed, it is determined that the character portion is present. That is, the fact that the image of the character is fine and the image is crushed by thickening is used. Alternatively, the determination is made based on the number of lines existing in the unit area. In other words, for characters, the fact that there are more lines than others is used.

The control unit 10 causes the display unit 60 to display the input image. At this time, the color of the label image determined as a character by the label determination unit 50 is converted to, for example, black and displayed. However, if the image showing the text and the background in contact with the image have the same color,
Change the brightness or color of the background so that text and background can be distinguished. It should be noted that the color used to display an image determined to be a character is not limited to black.

Here, the image displayed on the display unit 60 is
An arbitrary point can be designated by moving the mouse cursor 70, for example. That is, it is determined whether or not the label image determined to be a character is correct. If it is necessary to change the label image, an arbitrary point in the area to be changed of the display image is designated. Is specified. The position instruction from the operation unit 70 is notified to the control unit 10. At this time, a plurality of areas may be designated. Thus, even when an erroneous determination is made in the label determination unit 50, it can be easily corrected.

The control unit 10 outputs the position information and the label information from the operation unit 70 to the label determination unit 50. The label determination unit 50 reads the label image indicated by the position information from the labeling unit 40, and executes the character determination process again.

The character string extraction unit 55 extracts a character string from the array of label images determined to be characters by the label determination unit 50. The character string extracting unit 55 transfers the image of the extracted character string to the binarizing unit 80. The binarization unit 80 validates (for example, “1”) a label image determined to be a character string by the label determination unit 50 or a label image including position information (indicating a character) input from the operation unit 70, Binarization is performed so that other label images are invalid (for example, “0”). The binarization unit 80
The image obtained by the binarization is output to the character recognition unit 90.

The character recognizing unit 90 performs a character recognizing process by extracting a character pattern for each character from the binary image from the binarizing unit 80.

In this way, the color of the label image determined to be a character can be changed and displayed, and the operator can instruct whether or not the determination is incorrect. For this reason, the image to be subjected to the character recognition processing is assured, so that characters can be accurately read even for forms and the like that are not used for the optical character reading device.

[Effects of the Invention] As described above, according to the present invention, an image determined to be a character is displayed in a color indicating the character, and the determination can be corrected there. This makes it possible to reliably read a character such as a form using a color other than the dropout color which is not premised on the processing by the optical character reading device.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an optical character reading device according to one embodiment of the present invention. 10 control section, 20 scanning section, 30 sheet memory (storage means), 40 labeling section (label image detecting means), 50 label determination section, 55 character string extraction section, 60 …
... display unit, 70 ... operation unit (input means), 80 ... binarization unit, 90 ... character recognition unit.

Claims (1)

(57) [Claims] A scanning means for detecting a color image on a sheet on which characters and the like are written; a storage means for storing the color image detected by the scanning means; and a color image stored in the storage means. A label image detecting means for detecting a label image composed of a set of connected pixels for each color; and a label for determining whether or not the label image detected by the label image detecting means is a character label image. Determining means, changing only a label image determined as a character label image by the label determining means to a specific color, and displaying a color image detected by the scanning means; and displaying by the display means. Input means for inputting position information indicating an arbitrary position in the input color image, and the position information input by the input means. A binarizing unit that generates a binary image by validating a designated label image and a label image determined to be a character label image by the label determining unit, and invalidating the other, by the binarizing unit; And a character recognition processing means for performing character recognition processing based on the obtained binary image.