JP2016009395A - Document file generation device and document file generation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a document file generation device and a document file generation method for vectorizing a character image for drawing an image finely and neatly without increasing a file size.SOLUTION: In (a), the coordinates and vertical/horizontal dot widths of a base point d at the time of label acquisition are stored. A search is made on recorded coordinates within a character image, and, when both of a horizontal dot width (X coordinate) and a vertical dot width (Y coordinate) match, the searched one is assumed to be the relevant character, which is then registered in a font dictionary. In (b), the center of gravity e of the label is determined, and the feature value of the label from the position of the center of gravity e is calculated. A character for which the feature value matches is searched from vector image information by pattern matching. A next label is acquired, and the same search is made. However, when an already registered character is found by the search, the found character is not registered in the font dictionary. By the vectorization of a character image such as this, a drawing process acquires a font from the font dictionary and draws it.

Description

  The present invention relates to a document file generation apparatus and a document file generation method for converting a character image of a document obtained by character recognition into data and generating a document file of, for example, a PDF (Portable Document Format) format.

  There is a PDF (Portable Document Format) format as one type of electronic document standard. In a PDF format file (hereinafter referred to as “PDF file”), font information used in a document can be embedded in the PFD file itself. Therefore, the PFD file in which the font is embedded can be drawn (displayed or printed) as intended by the creator using the font embedded in the document even in an environment other than the environment in which the font is created.

  In PDF, a high compression method is used in order to reduce the file size when digitizing a document. This is done by identifying the character layer or image layer (image layer) for each object such as characters or graphics included in the image, and performing image processing or image processing according to the object included in each character layer or image layer of the layer. Image compression is performed. As a result, high image quality and high compression are achieved at the same time.

  By the way, vectorization of a character image is mentioned as one of the means for drawing a character image finely and finely drawn by PDF. However, when a character image is vectorized, it is necessary to describe the rendering processing of the vectorized font data on the PDF file, which is larger than the text data.

  In order to solve such a problem, for example, it is conceivable to apply a document creation method disclosed in Patent Document 1. That is, in Patent Document 1, a font name and a threshold value of the number of points (that is, size), which serve as a reference for embedding a font in a document file, are input as a table and used from the original data to be processed. If the font name and the number of points are acquired and the font name used in the original data is registered in the table, the point number in the original data is compared with the point number threshold in the table, and the threshold If there is a character with a point larger than that, a document creation method is proposed in which it is decided to embed the font.

JP2005-063052

  In the above-mentioned Patent Document 1, when creating document information that can include font information, not only the name of the font but also the number of points (that is, the size) of the font is created. The size of the document file can be reduced.

  However, if the number of points is given for each font, a pattern for each font is required, and the file size increases as the number of registered fonts increases.

  The present invention has been made in view of such circumstances, and a document that can easily and reliably perform vectorization of a character image for finely drawing an image without increasing the file size. It is an object to provide a file generation apparatus and a document file generation method.

A document file generation apparatus according to the present invention is a document file generation apparatus that generates a document file obtained by converting character images of a document obtained by character recognition into data, the vectorization means for vectorizing the character images, and a vectorized file Or an image processing unit that generates a document file, and the vectorization unit creates a character image by searching for elements having the same luminance in neighboring pixels of the binary image before the vectorization. Means, pattern matching means for comparing the feature quantity of the character image created by the character image creation means with the feature quantity of the character image obtained by the character recognition, and the character image having the same feature quantity First font dictionary registration means for registering the vectorized data in the font dictionary, the first font dictionary registration means It is characterized in that to generate the vectorization file using the vector data that more registered.
Further, the pattern matching unit of the document file generation device of the present invention determines a centroid of the character image, and calculates the feature amount that is a distance from the position of the centroid to the outermost contour line of the character image. It is characterized by comprising a quantity calculating means, searching the character image having the same feature quantity from vector image information, and registering the character image in the font dictionary.
Further, the vectorization means of the document file generation device of the present invention is characterized in that the character coordinate collation for collating the character coordinates from the base point of the character image obtained by the character recognition with the character coordinates included in the vectorized data. And a second font dictionary registration means for registering the vectorized data of the character image having the same character coordinates in the font dictionary, and the vectorized data registered by the second font dictionary registration means The vectorized file is generated by using the method.
Further, the character coordinate matching unit of the document file generation device of the present invention searches the character recognition information for the X coordinate of the drawing start position of the character image, and when the X coordinate of the drawing start position matches, the character image Coordinate search means for searching for the Y coordinate of the drawing start position, searching for the character image in which the X coordinate and the Y coordinate match from the vector image information, and registering the character image in the font dictionary It is characterized by.
In the document file generating apparatus of the present invention, when the vectorized data of the character image is registered in the font dictionary, the already registered character image is not registered.
The document file generation method of the present invention is a document file generation method for generating a document file in which character images of a document obtained by character recognition are converted into data, and a vectorization step for vectorizing the character images; Or an image processing step for generating a document file, wherein the vectorization step creates a character image by searching for elements having the same luminance in neighboring pixels of the binary image before the vectorization. A pattern matching step for comparing a feature amount of the character image created in the character image creation step with a feature amount of the character image obtained by the character recognition, and the character image having the same feature amount A first font dictionary registration step of registering the vectorized data in the font dictionary, the first font dictionary registration step It is characterized in that to generate the vectorization file using the vector data that more registered.
Further, the pattern matching step of the document file generation method of the present invention determines the center of gravity of the character image, and calculates the feature amount that is the distance from the position of the center of gravity to the outermost contour of the character image. An amount calculating step, wherein the character image having the matching feature amount is searched from vector image information, and the character image is registered in the font dictionary.
Further, the vectorization step of the document file generation method of the present invention includes a character coordinate collation for collating the character coordinates from the base point of the character image obtained by the character recognition with the character coordinates included in the vectorized data. And a second font dictionary registration step of registering the vectorized data of the character image having the same character coordinates in the font dictionary, and the vectorized data registered in the second font dictionary registration step The vectorized file is generated by using the method.
The character coordinate matching step of the document file generation method of the present invention searches the character recognition information for the X coordinate of the drawing start position of the character image, and if the X coordinate of the drawing start position matches, the character image A coordinate search step of searching for the Y coordinate of the drawing start position, searching for the character image in which the X coordinate matches the Y coordinate from the vector image information, and registering the character image in the font dictionary It is characterized by.
The document file generation method according to the present invention is characterized in that when the vectorized data of the character image is registered in the font dictionary, the already registered character image is not registered.

  The document file generation apparatus and the document file generation method of the present invention can draw an image finely and finely without increasing the file size.

It is a figure for demonstrating one Embodiment of the document file production | generation apparatus of this invention. 3 is a flowchart for explaining an outline of a document file generation method by the document file generation apparatus of FIG. 1. It is a figure for demonstrating the outline | summary of the image processing by the document file generation apparatus of FIG. It is a figure for demonstrating the vectorization process using vectorization and OCR (character recognition) in the document file generation apparatus of FIG. It is a figure for demonstrating the vectorization process using vectorization and OCR (character recognition) in the document file generation apparatus of FIG. It is a figure for demonstrating the vectorization process using vectorization and OCR (character recognition) in the document file generation apparatus of FIG. It is a figure for demonstrating the vectorization process using vectorization and OCR (character recognition) in the document file generation apparatus of FIG. It is a figure for demonstrating the vectorization process using vectorization and OCR (character recognition) in the document file generation apparatus of FIG. It is a figure for demonstrating the vectorization process using vectorization and pattern matching in the document file generation apparatus of FIG. It is a figure for demonstrating the vectorization process using vectorization and pattern matching in the document file generation apparatus of FIG.

  Hereinafter, an embodiment of a document file generation apparatus of the present invention will be described with reference to FIGS. First, as illustrated in FIG. 1, the document file generation apparatus 10 includes a control unit 11, an operation unit 12, a display unit 13, and a scanner unit 14.

  The control unit 11 controls the overall operation of the document file generation device 10 based on a predetermined program in a ROM (not shown). The operation reception unit 11a, the image recognition unit 11b, the image processing unit 11c, the memory 11d, A counter 11e and a vectorization unit 11f are provided.

  The operation accepting unit 11 a accepts an operation related to image processing by the operation unit 12. The image recognition unit 11b performs OCR (Optical Character Reader) of the character image read by the scanner unit 14. That is, the character image read by the scanner unit 14 is specified by collating with a prestored pattern, and data of the specified character image is obtained.

  The image processing unit 11c generates a document file in which the data vectorized by the vectorizing unit 11f is written (hereinafter referred to as a vectorized file) or a document file according to the file format of the document 20 described later. In the memory 11d, a character image read by the scanner unit 14 is stored.

  The counter 11e detects the number of characters recognized by the image recognition unit 11b (for example, when the character images “a”, “b”, and “c” are recognized, the character images “a”, “b”, and “c”). Count and register the number of characters for each). The vectorization unit 11f vectorizes the character image recognized by the image recognition unit 11b, and details thereof will be described later.

  The operation unit 12 is operated when instructing image processing, and is configured by a touch panel, for example. The display unit 13 displays a message for guiding image processing and the like, items for selecting image processing, and the like. The scanner unit 14 optically reads a character image of a later-described document 20 read by an image sensor (not shown).

  Next, an overview of image processing will be described with reference to FIGS. 2 and 3. First, the scanner unit 14 executes OCR (character recognition) by reading the document 20 as shown in FIG. 3, for example (step S1). 3 is, for example, a document in which a PDF file (hereinafter referred to as a PDF file) is printed. For convenience of explanation, for example, only a character layer on which character images a to d are displayed is displayed. Show.

  That is, as described above, the PDF file has a configuration based on a high compression method in which image processing and image compression are performed according to objects included in an image layer (image layer) of a character layer or an image layer.

  In addition, it is assumed that the reading of the document 20 by the scanner unit 14 is performed, for example, one line at a time from the top as shown by arrows. Here, when the document 20 is read, each time a new character image is OCR (character recognition), registration of the recognized character image is performed in the counter 11e (step S2).

  That is, when the character image “a” is first recognized, the recognized character image “a” is registered as the a counter 11e-1 of the counter 11e. Subsequently, when the next character image “a” is recognized, the number of characters of the a counter 11e-1 is added. That is, every time the character image “a” is recognized, the number of characters of the a counter 11e-1 is added.

  Next, when the character image “b” is recognized, the recognized character image “b” is registered as the b counter 11e-2 of the counter 11e. Subsequently, when the next character image of “b” is recognized, the number of characters of the b counter 11e-2 is added. That is, every time the character image “b” is recognized, the number of characters of the b counter 11e-2 is added.

  Next, when the character image “c” is recognized, the recognized character image “c” is registered as the c counter 11e-3 of the counter 11e. Subsequently, when the next character image of “c” is recognized, the number of characters of the c counter 11e-3 is added. That is, every time the character image “c” is recognized, the number of characters of the c counter 11e-3 is added.

  Next, the vectorization unit 11f performs vectorization of the character image (step S3). That is, vectorization of the character images “a” to “c” added by the a counter 11e-1, b counter 11e-2, and c counter 11e-3 of the counter 11e described above is performed.

  Next, for each character image added by the a counter 11e-1, b counter 11e-2, c counter 11e-3 by the image processing unit 11c, character coordinates and vectors obtained by OCR (character recognition). The target character is extracted by comparing with the character coordinates of the converted data (step S4). Incidentally, OCR (character recognition) information obtained by OCR (character recognition) includes character coordinates, character codes, and the like. The vectorized data includes the coordinates (positions) of the start and end points of the line. Therefore, the target character can be extracted by comparing the character coordinates of the vectorized data with the OCR (character recognition) information.

  Next, a font replacement process is executed by the image processing unit 11c (step S5). That is, the vectorized data of each character image by the vectorization unit 11f performed in step S3 is stored in, for example, the memory 11d described above.

  Next, based on the vectorized data of the character image stored in the memory 11d in step S5, a vectorized file is generated by the image processing unit 11c (step S6).

  As described above, in this embodiment, the vectorization unit 11f performs vectorization processing of each character image in step S3, and the vectorization unit 11f in step S6 generates a vectorized file.

  Next, a specific example of the image processing described above will be described. 4 to 8 illustrate vectorization processing for reducing the size of a document file using vectorization and OCR (character recognition). Note that the vectorization process described below is performed by the vectorization unit 11f described above.

  First, as shown in FIG. 4, the document 20 is read by the scanner unit 14 described above, and a character image and OCR (character recognition) information b are acquired. Note that the vector image information (vector data) a is information on the PDF file of the document 20 itself as described above, and is already acquired. A font dictionary c described below is included in the PDF file. Here, since the character to be drawn cannot be specified from the vector image information (vector data) a, the character code and the character coordinates are obtained from the OCR (character recognition) information b, and the character dictionary and the font dictionary c are obtained by the following procedure. Register.

That is, as shown in FIGS.
(1) For example, if the character image of “K” is OCR (character recognition), the X coordinate where the drawing start position matches between the left end and the right end of the character image of “K” is represented by OCR (character recognition) information b. Search from.
(2) When the OCR coordinates (the character coordinates of the OCR (character recognition) information b) match the X coordinate of the drawing start position of the vector image information a, the drawing start position matches between the upper end and the lower end of the Y coordinate. Search for coordinates.
(3) If both match, it is determined as a corresponding character and up to the fill of the vector image information a is registered as a character in the font dictionary c.
(4) When a registered character is found by the search, registration to the font dictionary c is not performed.

  As shown in FIG. 6, if the characters registered in the font dictionary c are, for example, “K”, “y”, “o”, and “c”, each character is displayed in the font dictionary c during the drawing process. Will be read from.

  Next, as shown in FIG. 7, when the search to the EOF (end of data) of the vector image information a is completed, the next search is performed on the OCR (character recognition) information b from the vector coordinates of the vector image information a. Call. Here, since there may be a character that cannot be recognized by OCR (character recognition), the vector image information a is searched again by the following procedure.

(5) Search for a vector data write start position that does not match a character recognized by OCR (character recognition).
(6) The matched characters are discarded because they are already registered in the separately recognized symbols and font dictionary c.
(7) Non-matching characters are additionally registered in one font dictionary c by collecting vector strings.
Here, a block of non-matching characters is created, but 90% or more are registered in the font dictionary c, leading to a reduction in file size.

Next, as shown in FIG.
(8) A font is acquired from the font dictionary c in which characters are registered, and drawing processing is performed by designating size and description coordinates. That is, for example, when “K”, “y”, “o”, “c”, “o”, and “o” are drawn, the font of each character is acquired from the font dictionary c.

  Next, a vectorization process for reducing the size of a document file using vectorization and pattern matching will be described with reference to FIG. In addition, the pattern matching demonstrated below shall be performed by the vectorization part 11f mentioned above.

First, as shown in FIG. 9, the original 20 is read by the scanner unit 14 described above, a character image is acquired, and registered in the font dictionary c in the following procedure.
That is, as shown in FIG.
(1) An element having the same luminance is searched for in the neighboring pixels of the binary image before vectorization, and a label is created. Here, for example, the label of the letter “K” is acquired.
(2) The coordinates of the location of the base point d at the time of label acquisition and the vertical and horizontal dot widths are stored.
(3) A search is performed on the described coordinates in the character image.
(4) Search the vector image information a for the X coordinate whose drawing start position matches between the left end and the right end of the character image having the horizontal dot width (X coordinate).
(5) If the X coordinates match, the vector image information a is searched for a Y coordinate whose drawing start position matches between the upper end and the lower end of the vertical dot width (Y coordinate).
(6) If both match, it is determined as a corresponding character, and up to the fill of the vector image information a is registered as a character in the font dictionary c described above.
(7) When a registered character is found by the search, registration to the font dictionary c is not performed.

Next, as shown in FIG.
(8) The center of gravity e of the label is determined, and the feature amount of the label from the position of the center of gravity e is calculated.
The feature amount is a distance (indicated by a dotted arrow) between the center of gravity e of the label and the outermost contour line. As a result, even if the target label is enlarged / reduced or rotated, it can be made to coincide with the period of the feature.
(9) Search the vector image information a for characters having the same feature quantity.
(10) The coordinates of the matched character and the horizontal and vertical width are stored.
(11) Repeat (9) and (10) until no character is found.
(12) The next label is acquired and pattern matching similar to the above is performed.
At this time, the stored characters and coordinates are excluded from the next search target.
(13) In the drawing process, the font is acquired from the font dictionary c, and the size and description coordinates are designated.

  As described above, in the present embodiment, the image processing unit 11c registers the vectorized data of the character image that matches by matching the character coordinates obtained by character recognition with the character coordinates included in the vectorized data in the font dictionary c. it can. Also, vectorized data of matching character images can be registered in the font dictionary by matching (pattern matching) with a feature amount calculated from a character image obtained by character recognition.

  In addition, when registering in the font dictionary c, since registration is not performed for characters that have already been registered, it is possible to prevent the file size from increasing even if the number of character images to be registered increases. can do.

  The document file generation apparatus and the document file generation method of the present invention can easily and reliably perform vectorization of a character image for finely drawing an image without increasing the file size.

  As mentioned above, although this invention was demonstrated by specific embodiment, it cannot be overemphasized that the said embodiment is an illustration of this invention and is not limited to this embodiment.

  The present invention is suitable for a document file generation apparatus and a document file generation method, but is not limited to the document file generation apparatus and the document file generation method, and is generally applicable to an apparatus having a function for generating a document file and document file generation in general. it can.

DESCRIPTION OF SYMBOLS 10 Document file generator 11 Control part 11a Operation reception part 11b Image recognition part 11c Image processing part 11d Memory 11e Counter 11e-1 a counter 11e-2 b counter 11e-3 c counter 11f Vectorization part 12 Operation part 13 Display part 14 Scanner unit 20 Document a Vector information (vector data)
b OCR (character recognition) information c Font dictionary d Base point e Center of gravity

Claims (10)

A document file generation device that generates a document file obtained by converting character images of a document obtained by character recognition into data,
Vectorizing means for vectorizing the character image;
Image processing means for generating a vectorized file or a document file,
The vectorization means includes:
A character image creating means for searching for an element having the same luminance in neighboring pixels of the binary image before the vectorization and creating the character image;
Pattern matching means for comparing the feature amount of the character image created by the character image creation means with the feature amount of the character image obtained by the character recognition;
A first font dictionary registration means for registering vectorized data of the character image having the same feature quantity in a font dictionary;
An apparatus for generating a document file, wherein the vectorized file is generated using the vectorized data registered by the first font dictionary registering means. The pattern matching means includes
A feature amount calculating means for determining a center of gravity of the character image and calculating the feature amount that is a distance from the position of the center of gravity to the outermost contour line of the character image;
2. The document file generation apparatus according to claim 1, wherein the character image having the same feature amount is searched from vector image information, and the character image is registered in the font dictionary. The vectorization means includes:
Character coordinate matching means for matching the character coordinates from the base point of the character image obtained by the character recognition with the character coordinates included in the vectorized data;
A second font dictionary registering means for registering the vectorized data of the character image with the matching character coordinates in the font dictionary;
3. The document file generating apparatus according to claim 1, wherein the vectorized file is generated using the vectorized data registered by the second font dictionary registering unit. The character coordinate matching means includes:
Coordinate search means for searching for the X coordinate of the drawing start position of the character image from character recognition information and searching for the Y coordinate of the drawing start position of the character image when the X coordinate of the drawing start position matches,
4. The document file generation apparatus according to claim 3, wherein the character image in which the X coordinate and the Y coordinate coincide with each other is searched from the vector image information, and the character image is registered in the font dictionary.   The registration of the already registered character image is not performed when the vectorized data of the character image is registered in the font dictionary. Document file generation device described in 1. A document file generation method for generating a document file obtained by converting character images of a manuscript obtained by character recognition into data,
A vectorization step of vectorizing the character image;
An image processing step for generating a vectorized file or a document file,
The vectorization step includes
A character image creation step of searching for an element having the same brightness in neighboring pixels of the binary image before the vectorization and creating the character image;
A pattern matching step for collating the feature amount of the character image created in the character image creation step with the feature amount of the character image obtained by the character recognition;
A first font dictionary registration step of registering vectorized data of the character image having the same feature quantity in a font dictionary;
A document file generation method, wherein the vectorized file is generated using the vectorized data registered in the first font dictionary registration step. The pattern matching process includes:
Determining a center of gravity of the character image, and comprising a feature amount calculating step of calculating the feature amount that is a distance from the position of the center of gravity to the outermost contour line of the character image,
The document file generation method according to claim 6, wherein the character image having the same feature amount is searched from vector image information, and the character image is registered in the font dictionary. The vectorization step includes
A character coordinate matching step for collating the character coordinates from the base point of the character image obtained by the character recognition with the character coordinates included in the vectorized data;
A second font dictionary registration step of registering the vectorized data of the character image with the matching character coordinates in the font dictionary;
The document file generation method according to claim 6 or 7, wherein the vectorized file is generated using the vectorized data registered in the second font dictionary registration step. The character coordinate matching step includes:
A coordinate search step of searching for the X coordinate of the drawing start position of the character image from character recognition information and searching for the Y coordinate of the drawing start position of the character image when the X coordinate of the drawing start position matches,
9. The document file generation method according to claim 8, wherein the character image in which the X coordinate matches the Y coordinate is searched from the vector image information, and the character image is registered in the font dictionary.   10. The registration of the already registered character image is not performed when the vectorized data of the character image is registered in the font dictionary. Document file generation method described in 1.

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