JP4091308B2 - Information processing apparatus and character recognition method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an information processing apparatus having a character recognition function and a character recognition method.
[0002]
[Prior art]
An OCR (Optical Character Reader) is widely used as a means for reading a character written on a form such as paper or a document as an image and converting it into electronic character data. In such OCR, character recognition is performed after a character image is read.
[0003]
In order to improve the accuracy of character recognition results, in general, after character recognition is performed, further post-processing using a context or a dictionary is performed.
[0004]
[Problems to be solved by the invention]
Post-processing using context and dictionary is effective for general characters. However, there are many objects to which post-processing by context or dictionary cannot be applied.
[0005]
For example, as the Internet has become widespread in recent years, electronic address information such as URLs (Uniform Resource Locators) and e-mail addresses of Web pages are becoming subject to character recognition. This is one of the objects that are difficult to perform post-processing using a dictionary.
[0006]
The present invention has been made in view of the above circumstances, and an information processing apparatus and a character recognition method capable of obtaining a highly accurate character recognition result even when the character recognition target includes electronic address information. The purpose is to provide.
[0007]
[Means for Solving the Problems]
An information processing apparatus according to the present invention is an information processing apparatus having a character recognition function, and performs character recognition on a character string region of a read image to generate a character candidate and its reliability. A recognizing unit, a post-processing determining unit that performs a post-processing determination including determining whether or not there is a character string corresponding to the electronic address information based on a result of character recognition by the character recognizing unit; As a result of the determination, if there is a character string corresponding to the electronic address information, from the individual character candidates constituting the character string corresponding to the electronic address information obtained as the character recognition result of the character recognition means and its reliability a candidate generation unit for generating a candidate character string corresponding to at least one of the electronic address information, attempts to connect to the network by using the candidates generated by the candidate generation unit A network connection means for, wherein when the candidate string connected by a network connecting means corresponds to the electronic address information success is only one, the candidate character string corresponding to the electronic address information the connection is successful When there are a plurality of character string candidates corresponding to the electronic address information that is determined as the character recognition result by the character recognition means and successfully connected by the network connection means, the character strings corresponding to the plurality of electronic address information It comprises recognition confirmation means for confirming a character string candidate corresponding to electronic address information with the highest reliability among the candidates as a character recognition result by the character recognition means .
[0008]
An information processing apparatus according to the present invention is an information processing apparatus having a character recognition function, and analyzes a layout from a document image input unit that reads an image of the document and an image input by the document image input unit. Layout analysis means for extracting a character string area, character recognition means for performing character recognition on the area extracted by the layout analysis means, and generating each character candidate and its reliability, and the character recognition means Post-processing determination means for performing post-processing determination including attribute determination whether there is a character string corresponding to the electronic address information and reliability determination of the character string corresponding to the electronic address information based on the result of character recognition by As a result of attribute determination and reliability determination by the post-processing determination means, there is a character string corresponding to the electronic address information, and it reaches a certain level of reliability. If those do not, the candidate generation unit for generating a candidate character string corresponding to at least one of the electronic address information to the string, the connection to the network by using the candidates generated by the candidate generation unit When there is only one character string candidate corresponding to the network connection means to be tried and electronic address information successfully connected by the network connection means, candidate character strings corresponding to the electronic address information successfully connected Is determined as a character recognition result by the character recognition means, and when there are a plurality of character string candidates corresponding to the electronic address information successfully connected by the network connection means, the character strings corresponding to the plurality of electronic address information Character candidate corresponding to the electronic address information with the highest reliability among the candidates Characterized by comprising a recognition determination means for determining as a character recognition result by.
[0009]
The character recognition method according to the present invention is a character recognition method applied to an information processing apparatus having a character recognition function, and performs character recognition of a character string area of a read image , and each character candidate and its character generating the reliability, based on the character recognition result, it performs a post-processing determination includes determining whether there is a character string corresponding to the electronic address information, the result of determination by the post-processing determining means, electronic address information If there is a character string corresponding to the character recognition means, at least one electronic address information is determined from the individual character candidates constituting the character string corresponding to the electronic address information obtained as the character recognition result of the character recognition means and its reliability. generates a candidate of the corresponding string, attempts to connect to the network using the generated candidate, the electronic address information attempt to connect to the network is successful If there is only one character string candidate to be connected, the character string candidate corresponding to the electronic address information for which this connection was successful is confirmed as a character recognition result by the character recognition means, and an attempt to connect to the network is made. If there are multiple character string candidates corresponding to the successful electronic address information, among the character string candidates corresponding to the plurality of electronic address information, the character string candidates corresponding to the electronic address information with the highest reliability. Is determined as a character recognition result by the character recognition means .
[0010]
A character recognition method according to the present invention is a character recognition method applied to an information processing apparatus having a character recognition function, which reads an image of the document, analyzes a layout from the read image, and determines a character string region. Extract and perform character recognition on the extracted area to generate each character candidate and its reliability, and whether or not there is a character string corresponding to the electronic address information based on the result of character recognition Post-processing determination including determination and reliability determination of the character string corresponding to the electronic address information. As a result of attribute determination and reliability determination, there is a character string corresponding to the electronic address information, and it is constant If those do not reach the reliability, at least one of generating a character string candidates corresponding to the electronic address information, connection to the network by using the generated candidate for the character string Line, and wherein, when connected by a network connecting means is only one candidate of the corresponding character string in the electronic address information succeeds, the character recognition of the character string candidates corresponding to the electronic address information the connection is successful If there are a plurality of character string candidates that correspond to the electronic address information that has been successfully connected by the network connection means as a result of character recognition by the means, out of the character string candidates that correspond to the plurality of electronic address information The character string candidate corresponding to the electronic address information having the highest reliability is determined as a character recognition result by the character recognition means .
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0012]
FIG. 1 is a block diagram showing a configuration of an information processing apparatus according to an embodiment of the present invention.
[0013]
The information processing apparatus inputs a document image and performs character recognition, and includes a document image input unit 10, a layout analysis unit 20, a character recognition unit 30, a post-processing determination unit 40, a candidate generation unit 50, and a network connection unit. 60, a recognition confirmation unit 70 is provided.
[0014]
The document image input unit 10 inputs a document image (electronic image data including character information).
[0015]
The layout analysis unit 20 analyzes a layout from the image read by the document image input unit 10 and extracts a character string region to be recognized.
[0016]
The character recognition unit 30 performs character recognition on the region extracted by the layout analysis unit 20, and generates a candidate for each character and its reliability as a result of character recognition.
[0017]
As shown in FIG. 2, the post-processing determination unit 40 includes an attribute determination unit 41 and a reliability determination unit 42. Based on the result of character recognition by the character recognition unit 30, a character string corresponding to the electronic address information is displayed. Whether or not there is an attribute determination (processing in the attribute determination unit 41) and post-processing determination (processing in the reliability determination unit 42) including reliability determination of the character string corresponding to the electronic address information are performed. The attribute determination is performed based on the rules of character string arrangement, form information, and the like.
[0018]
The candidate generation unit 50 determines that the character string corresponding to the electronic address information exists as a result of attribute determination and reliability determination by the post-processing determination unit 40 and does not reach a certain level of reliability. At least one candidate is generated for the sequence.
[0019]
The network connection unit 60 tries (verifies) connection to the network using the candidates generated by the candidate generation unit 50.
[0020]
The recognition confirmation unit 70 finally determines the character recognition result by the character recognition unit 30 using the result of connection by the network connection unit 60. For example, by adopting candidate electronic address information that has been confirmed to be correct as a result of network connection, the character recognition result is finally determined.
[0021]
FIG. 3 is a diagram illustrating an example of a document image read by the document image input unit 10.
[0022]
An image 70 shown in the figure includes Web page URL (Uniform Resource Locator) and electronic address information corresponding to an electronic mail address.
[0023]
When the layout of the image 70 is analyzed by the layout analysis unit 20, individual character string regions are cut out as shown by the frames in FIG. 4, and the character recognition unit 30 applies the individual character string regions to the individual character string regions. Character recognition processing is performed. In this case, an area 71 including an URL (Uniform Resource Locator) address and an area 72 including an e-mail address exist in each extracted character string area.
[0024]
FIG. 5 is a diagram for explaining an example of a recognition result by the character recognition unit 30.
[0025]
In the figure, the character string “www.tokyo.co.jp” included in the URL address area 71 (FIG. 4) among the individual character string areas recognized by the character recognition unit 30 is shown as an example. Yes. Among the character strings, for example, when the character “k” indicated by reference numeral 73 is recognized, “first candidate character k” (reliability 40), “second candidate character h” in descending order of reliability. "(Reliability 30)", "Third candidate character b" (Reliability 20),... Such identification results are obtained individually for other characters. The identification result obtained for each character is sent to the post-processing determination unit 40 and used in the post-processing determination.
[0026]
In the post-processing determination unit 40, for example, for the URL address area 71 shown in FIG. 4, the character string indicates the URL address from the recognition of the character string such as “www” at the head. It is determined that connection to the network should be attempted using the recognized and generated candidates. Similarly, for the e-mail address area 72 shown in FIG. 4, it is recognized that the character string is an e-mail address from a character string such as “˜@˜co.jp” and is generated. It is determined that the connection to the network should be tried using the candidates.
[0027]
On the other hand, the candidate generation unit 50 generates a plurality of candidate character strings to be tried to connect to the network from the individual character candidates already obtained as recognition results and their reliability.
[0028]
For example, “www.tokyo.co.jp”, “www.tohyo.co.jp”,... Are generated as candidates for the URL included in the URL address area 71 shown in FIG. . Also, “taro@tokyo.co.jp”, “taro@tohyo.co.jp”, etc. are candidates for the email address included in the email address area 72 shown in FIG. Is generated as
[0029]
The candidate generation unit 50 holds attribute information including characters that specify the attribute of the electronic address information, and if the candidate character string includes characters indicating an inappropriate attribute, the attribute information Has a function of correcting the character string based on the For example, if “ca.jp” is included as a character indicating an inappropriate attribute, the candidate generation unit 50 can automatically correct this to “co.jp”.
[0030]
The plurality of candidate character strings generated by the candidate generation unit 50 are sent to the network connection unit 60 in order from the candidate with the highest reliability. The network connection unit 60 attempts network connection using the candidate character string received from the candidate generation unit 50. As a result of trying the connection using the candidate character string, the network connection unit 60 sends the result of whether or not the connection is successful to the recognition confirmation unit 70.
[0031]
In the recognition confirmation unit 70, if there is only one correctly connected, the candidate is selected. If there are a plurality of candidates, the candidate having the highest reliability is selected. The recognition result is determined by a method such as adopting the candidate having the highest reliability among the candidates obtained in the section 50).
[0032]
Next, the operation of the information processing apparatus according to the present embodiment will be described with reference to the flowchart of FIG.
[0033]
When a document image (electronic image data including character information) is read by the document image input unit 10 (step S1), the layout analysis unit 20 analyzes the layout and extracts a character string region (step S1). Step S2).
[0034]
Next, character recognition by the character recognition unit 30 is performed on the region extracted by the layout analysis unit 20 (step S3). As a result of this character recognition, each character candidate and its reliability are generated.
[0035]
Next, post-processing determination by the post-processing determination unit 40 is performed from the result of character recognition by the character recognition unit 30. In this post-processing determination, an attribute determination as to whether there is a character string corresponding to the electronic address information and a reliability determination of the character string corresponding to the electronic address information are performed (step S4).
[0036]
As a result of the attribute determination and the reliability determination, if a character string corresponding to the electronic address information exists and does not reach a certain reliability (Yes in step S5), a trial (verification) by network connection is performed. The candidate generation unit 50 is activated as deemed necessary, and a plurality of candidates for the corresponding character string are generated by the candidate generation unit 50 (step S6).
[0037]
If the above condition is not satisfied (No in step S5), a trial (verification) by network connection is not necessary, and the character recognition result by the character recognition unit 30 is determined as it is in the recognition determination unit 70 (step S8). ).
[0038]
The plurality of candidates generated by the candidate generation unit 50 are sent to the network connection unit 60 in descending order of priority, and network connection using these candidates is tried (verified) (step S7).
[0039]
The result of the connection verification by the network connection unit 60 is sent to the recognition confirmation unit 70. In the recognition confirmation unit 70, the result of character recognition by the character recognition unit 30 is finally confirmed using this result (step S8).
[0040]
In addition to the method of confirming the connection by the network connection unit 60, other methods such as inquiring to the directory service or confirming only the domain unit using a whois server or the like are adopted. May be. In addition, when the recognition result is an e-mail address, a method may be employed in which the e-mail is actually transmitted and a determination is made based on the presence or absence of a reply e-mail.
[0041]
As described above, according to the present embodiment, even when electronic address information such as an e-mail address or a URL address is included in the character recognition target, the recognition result is obtained through the network connection according to the recognized character attribute. By confirming, it is possible to improve the accuracy of character recognition.
[0042]
Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.
[0043]
【The invention's effect】
As described above in detail, according to the present invention, it is possible to obtain a highly accurate character recognition result even when the character recognition target includes electronic address information.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an information processing apparatus according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a configuration of a post-processing determination unit shown in FIG.
FIG. 3 is a view showing an example of a document image input to the document image input unit shown in FIG. 1;
4 is a diagram showing a state in which individual character string regions are cut out by the layout analysis unit shown in FIG. 1;
FIG. 5 is a view for explaining an example of a recognition result by a character recognition unit shown in FIG. 1;
FIG. 6 is a flowchart for explaining the operation of the information processing apparatus according to the embodiment;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Document image input part 20 ... Layout analysis part 30 ... Character recognition part 40 ... Post-processing determination part 41 ... Attribute determination part 42 ... Reliability determination part 50 ... Candidate generation part 60 ... Network connection part 70 ... Recognition confirmation part 71, 72 ... Area 73 ... Character

Claims (10)

An information processing apparatus having a character recognition function,
Character recognition means for performing character recognition on the character string area of the read image and generating each character candidate and its reliability ;
Post-processing determination means for performing post-processing determination including determination of whether or not there is a character string corresponding to the electronic address information based on the result of character recognition by the character recognition means;
When there is a character string corresponding to the electronic address information as a result of the determination by the post-processing determining means, the individual character constituting the character string corresponding to the electronic address information obtained as the character recognition result of the character recognition means Candidate generation means for generating a candidate for a character string corresponding to at least one electronic address information from the candidate and its reliability,
Network connection means for trying to connect to the network using the candidates generated by the candidate generation means;
If there is only one character string candidate corresponding to the electronic address information successfully connected by the network connection means, the character recognition candidate selected by the character recognition means is the character string candidate corresponding to the electronic address information successfully connected. When there are a plurality of character string candidates determined as recognition results and corresponding to the electronic address information successfully connected by the network connection means, the most reliable of the character string candidates corresponding to the plurality of electronic address information. An information processing apparatus comprising: a recognition confirmation unit configured to determine a character string candidate corresponding to electronic address information having a high degree as a character recognition result by the character recognition unit. An information processing apparatus having a character recognition function,
Document image input means for reading an image of the document;
Layout analysis means for analyzing the layout from the image input by the document image input means and extracting a character string area;
Character recognition means for performing character recognition on the region extracted by the layout analysis means, and generating each character candidate and its reliability;
Based on the result of character recognition by the character recognition means, post-processing determination is performed including attribute determination as to whether or not there is a character string corresponding to the electronic address information, and reliability determination of the character string corresponding to the electronic address information. Post-processing determination means;
As a result of attribute determination and reliability determination by the post-processing determination means, if a character string corresponding to the electronic address information exists and does not reach a certain level of reliability, at least one of the character strings Candidate generation means for generating candidate character strings corresponding to one electronic address information ;
Network connection means for trying to connect to the network using the candidates generated by the candidate generation means;
If there is only one character string candidate corresponding to the electronic address information successfully connected by the network connection means, the character recognition candidate selected by the character recognition means is the character string candidate corresponding to the electronic address information successfully connected. When there are a plurality of character string candidates determined as recognition results and corresponding to the electronic address information successfully connected by the network connection means, the most reliable of the character string candidates corresponding to the plurality of electronic address information. An information processing apparatus comprising: a recognition confirmation unit configured to determine a character string candidate corresponding to electronic address information having a high degree as a character recognition result by the character recognition unit.   3. The information processing apparatus according to claim 1, wherein the post-processing determination unit can recognize a URL (Uniform Resource Locator) address as the electronic address information.   3. The information processing apparatus according to claim 1, wherein the post-processing determination unit can recognize an electronic mail address as the electronic address information.   3. The information processing according to claim 1, wherein, when the candidate generating unit generates a plurality of candidates, the network connection unit tries to connect to the network in order from a candidate having a high reliability. apparatus. The candidate generation means holds attribute information including characters specifying the attribute of the electronic address information, and if the candidate character string includes characters indicating an inappropriate attribute, the attribute information 3. The information processing apparatus according to claim 1, further comprising means for correcting the character string based on the information. A character recognition method applied to an information processing apparatus having a character recognition function,
Perform character recognition of the character string area of the read image, generate each character candidate and its reliability,
Based on the result of the character recognition, perform post-processing determination including determination whether there is a character string corresponding to the electronic address information,
When there is a character string corresponding to the electronic address information as a result of the determination by the post-processing determining means, the individual character constituting the character string corresponding to the electronic address information obtained as the character recognition result of the character recognition means Generate a string candidate corresponding to at least one electronic address information from the candidate and its reliability,
Attempts to connect to the network using the generated candidate,
When there is only one character string candidate corresponding to the electronic address information successfully connected to the network, the character recognition means determines that the character string candidate corresponds to the electronic address information successfully connected. When there are a plurality of character string candidates corresponding to the electronic address information that is determined as a character recognition result and the connection attempt to the network is successful, among the character string candidates corresponding to the plurality of electronic address information, A character recognition method characterized in that a character string candidate corresponding to electronic address information having the highest reliability is determined as a character recognition result by the character recognition means . A character recognition method applied to an information processing apparatus having a character recognition function,
Reads an image of the document,
Analyzing the layout from the scanned image and extracting the character string area
Character recognition is performed on the extracted area, and each character candidate and its reliability are generated.
Based on the result of character recognition, the attribute determination whether there is a character string corresponding to the electronic address information, and the post-processing determination including the reliability determination of the character string corresponding to the electronic address information,
As a result of attribute determination and reliability determination, if a character string corresponding to electronic address information exists and does not reach a certain level of reliability, it corresponds to at least one electronic address information for the character string Generate a string candidate
Attempts to connect to the network using the generated candidate,
If there is only one character string candidate corresponding to the electronic address information successfully connected by the network connection means, the character recognition candidate selected by the character recognition means is the character string candidate corresponding to the electronic address information successfully connected. When there are a plurality of character string candidates determined as recognition results and corresponding to the electronic address information successfully connected by the network connection means, the most reliable of the character string candidates corresponding to the plurality of electronic address information. A character recognition method characterized in that a character string candidate corresponding to electronic address information having a high degree is determined as a character recognition result by the character recognition means .   9. The character recognition method according to claim 7, wherein when a plurality of candidates are generated in the generation of the candidates, connection to the network is tried in order from a candidate having a high reliability.   If attribute information including a character specifying the attribute of the electronic address information is held, and the candidate character string includes a character indicating an inappropriate attribute, the character is based on the attribute information. The character recognition method according to claim 7 or 8, wherein the column is corrected.

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