JP5765452B2 - Annotation addition / restoration method and annotation addition / restoration apparatus - Google Patents

Description

The present invention is based on the grant request from the user, the annotation is applied to the display based on the content, based on the reference request from the user, annotated restored side Ho及 beauty annotated to restore annotations to display based on the content The present invention relates to a restoration device.

  In recent years, Web annotation technology that adds annotation (annotation) as secondary information to a display (for example, a Web page) based on content (for example, HTML data) on a network such as the Internet or an intranet has been frequently used. Note that the annotation refers to content pasted on a display (Web page) based on content (HTML data).

  Web annotation technology is a technology that allows another third party who is different from the content creator to add content (such as comments and opinions), underlines, markers, etc. An annotation is given, and the annotation given to the Web page is restored when browsing (referring to) the Web page.

  FIG. 1 is a screen image diagram of an example of a Web page on which an annotation in the form of a sticky note is displayed. In FIG. 1, annotation 1 is displayed on a Web page in a form like a sticky note.

  The Web annotation technology retains location information (for example, URL) of the Web page to which the annotation 1 is added when the annotation 1 is added, and is given to the Web page when browsing the Web page specified by the URL. By restoring the annotation 1, the annotation 1 can be restored even when browsing the Web page with time or browsing the Web page by a third party different from the annotator to which the annotation 1 is added. Such Web annotation technology is widely used for information sharing, proofreading support, review support, survey support, advertising systems, and the like.

  Conventionally, when annotation 1 is assigned to a web page and annotation 1 is shared by a plurality of users, the location information of the web page on the intermediary server and the structure position information and content of the annotation 1 attached to the web page And are registered. The structure position information represents the position on the content of the Web page to which the annotation 1 is assigned. The structure position information is represented by a tree structure path expression (XPath).

  When a user specifies location information and requests a Web page, the mediation server acquires content from the Web server. If the annotation 1 corresponding to the location information designated by the user is registered, the mediation server restores the annotation 1 to the position on the content expressed by the structural position information and transmits it to the user's client. As described above, in the conventional Web annotation technology, the annotation 1 given to the Web page is shared by a plurality of users (see, for example, cited document 1).

JP 2003-150542 A

  In the conventional Web annotation technology, the position on the content of the Web page to which the annotation is added is expressed by XPath. In the conventional Web annotation technology, when restoring an annotation, the registered XPath is used to specify the position on the content where the annotation is restored.

  By the way, in the Web annotation technology, another third party different from the content creator gives an annotation to the Web page. Therefore, the author may change the contents of the content regardless of the assigned annotation. When the contents are changed, the tree structure of the contents changes, and the registered XPath has no meaning. If the meaning of XPath disappears, the conventional Web annotation technology has a problem that the position on the content where the annotation is restored cannot be specified.

  FIG. 2 is an explanatory diagram showing content and a tree structure when XPath is acquired. FIG. 2A shows the content when XPath is acquired. FIG. 2B shows a tree structure of the content shown in FIG. In the content of FIG. 2, XPath representing the tag <TABLE> is “/ HTML / BODY / TABLE”.

  FIG. 3 is an explanatory diagram showing content and a tree structure whose contents are changed. FIG. 3A shows content whose contents have been changed. FIG. 3B shows a tree structure of the content shown in FIG. In the content of FIG. 3, XPath indicating the tag <TABLE> is “/ HTML / BODY / DIV / TABLE”.

  As described above, when the content shown in FIG. 2 is changed to the content shown in FIG. 3, the XPath “/ HTML / BODY / TABLE” registered when the XPath is acquired does not exist in the content shown in FIG. It becomes impossible to specify the position on the content to restore.

  In the conventional Web annotation technology, there is a problem that the position on the content where the annotation is restored cannot be specified even though the tag <TABLE> has been deleted due to the change even though it exists in the content. It was.

  In the Web annotation technology, there is a time lag between annotation assignment and annotation restoration. For this reason, it is unavoidable in the Web annotation technology that the structure of the content changes from when the annotation is added to when the annotation is restored.

The present invention also as content is changed, and an object thereof is to provide a annotated restore lateral Ho及 beauty annotated restoring apparatus that can identify the position on the content to restore the annotations.

In order to solve the above-mentioned problem, an embodiment of the present invention is an annotation assignment / restoration method, wherein when an annotation is given to a computer at any position on content having a structure, the position of the position in the content is determined. a process of storing the information stored in the storage information and the lower structure of the upper side of the structure in association with the annotation, based on the stored information of the upper side of the structure of the position annotated for the content, annotations restore If it is not detected that the content matching the stored higher-order structure is included in the content of the content, the content to be reconstructed based on the storage information of the lower-order structure at the position where the annotation is added Whether a structure that matches the stored subordinate structure is included It performs output when it detects that includes structure that matches the stored the lower side of the structure, the position to be executed and a process of outputting the annotation in association with, the lower side of the position to be stored structure Is a structure relating to one path selected according to the appearance frequency from a plurality of paths on the lower side of the position.

  In addition, what applied the component, the expression, or arbitrary combinations of the component of one Embodiment of this invention to a method, an apparatus, a system, a computer program, a recording medium, a data structure, etc. is also effective as an aspect of this invention. .

  As described above, according to an embodiment of the present invention, even if the content is changed, the position on the content where the annotation is restored can be specified.

It is a screen image figure of an example of the web page on which the annotation of a format like a sticky note is displayed. It is explanatory drawing showing the content at the time of XPath acquisition, and the tree structure. It is explanatory drawing showing the content and the tree structure in which the content was changed. It is a block diagram of an example of the system of a present Example. It is a block diagram of the other example of the system of a present Example. It is a block diagram of an example of a user terminal. It is a processing block diagram of an example of a user terminal. It is a block diagram of an example of the annotation information stored in annotation DB. It is explanatory drawing for demonstrating the characteristic XPath. It is explanatory drawing for demonstrating feature information. It is explanatory drawing showing the example which cannot identify an object node by XPath. It is explanatory drawing showing the example in which a some target node is specified by the wild card search using the characteristic XPath. It is a flowchart of an example of an annotation provision process. It is a flowchart of an example of an annotation restoration process. It is a block diagram of an example of the browser to which the annotation program of a present Example is applied.

  Next, modes for carrying out the present invention will be described based on the following embodiments with reference to the drawings.

(System configuration)
FIG. 4 is a block diagram of an example of the system of the present embodiment. The system illustrated in FIG. 4 includes a user terminal 10, a content server 20, an annotation information management server 30, and a network 50. The user terminal 10, the content server 20, and the annotation information management server 30 are connected via a network 50 so that data communication is possible. The network 50 may be any communication network capable of data communication, such as the Internet or a LAN.

  A browser 11 is installed on the user terminal 10. The browser 11 has an extended function added by a plug-in 12. The content server 20 stores content 21 such as Web pages. The annotation information management server 30 has an annotation DB 31 and manages annotation information.

  FIG. 5 is a configuration diagram of another example of the system of this embodiment. The system shown in FIG. 5 includes a user terminal 10, a content server 20, an annotation information management server 30, and a network 50, as in the system of FIG. Note that the browser 11 in FIG. 5 does not have an extended function added by the plug-in 12. Further, the system of FIG. 5 is different from the system of FIG. 4 in that the content server 20 stores the content 21 of which the script 22 constitutes a part.

  The system of FIG. 4 implements the annotation function according to the present embodiment by the plug-in 12. The system of FIG. 5 implements the annotation function according to the present embodiment by the script 22.

(Configuration of user terminal 10)
FIG. 6 is a configuration diagram of an example of a user terminal. The user terminal 10 includes an input device 61, an output device 62, a drive device 63, an auxiliary storage device 64, a main storage device 65, an arithmetic processing device 66, and an interface device 67 that are mutually connected by a bus B.

  The input device 61 is a keyboard or a mouse. The input device 61 is used for inputting various signals. The output device 62 is a display device or the like. The output device 62 is used to display various windows and data. The interface device 67 is a modem, a LAN card, or the like. The interface device 67 is used for connecting to the network 50.

  The annotation program according to the present embodiment is at least a part of various programs that control the user terminal 10. The annotation program is provided, for example, by distributing a recording medium 68 on which the annotation program is recorded, downloading a program from the network 50, or the like. The recording medium 68 on which the annotation program is recorded is information such as a CD-ROM, a flexible disk, a magneto-optical disk, etc., a recording medium for recording information optically, electrically or magnetically, a ROM, a flash memory, etc. Various types of recording media such as a semiconductor memory for electrical recording can be used.

  When the recording medium 68 on which the annotation program is recorded is set in the drive device 63, the annotation program is installed in the auxiliary storage device 64 from the recording medium 68 via the drive device 63. The annotation program downloaded from the network 50 is installed in the auxiliary storage device 64 via the interface device 67. The auxiliary storage device 64 stores the installed annotation program and also stores necessary files and data.

  The main storage device 65 stores the annotation program read from the auxiliary storage device 64. The arithmetic processing unit 66 implements various processes as will be described later in accordance with the annotation program stored in the main storage device 65.

(Processing block of user terminal 10)
FIG. 7 is a processing block diagram of an example of a user terminal. The user terminal 10 includes a Web resource acquisition unit 71, a Web resource analysis result preparation unit 72, an annotation information storage unit 73, an annotation assignment unit 74, an annotation structure position acquisition unit 75, an annotation embedding unit 76, an annotation information acquisition unit 77, an annotation A restoration unit 78, an annotation structure position acquisition unit 79, and an annotation embedding unit 80 are included.

  When the location information (URL) of the content that is the Web resource is specified, the Web resource acquisition unit 71 acquires the content of the specified URL from the content server 20. The Web resource analysis result preparation unit 72 can use the extracted content as the Web resource analysis result as it is, but normally holds the tree structure that is the result of parsing the content as the Web resource analysis result.

  The annotation assigning unit 74 accepts an operation for giving an annotation to a display (Web page) based on content from a user. The annotation structure position acquisition unit 75 acquires structure position information (XPath) representing the position on the content of the Web page to which the user has added the annotation, based on the operation for adding the annotation. The annotation embedding unit 76 embeds the annotation content at the specified position of the Web resource analysis result based on the structure position information acquired by the annotation structure position acquisition unit 75. The annotation giving unit 74 can display the Web page to which the annotation is given by passing the Web resource analysis result to the rendering engine and drawing it.

  The annotation information storage unit 73 stores annotation information for restoring the annotation given to the user in the annotation DB 31. The annotation information includes the URL of the content of the Web page to which the annotation has been added, XPath that is the structure position information of the annotation, feature XPath that will be described later, feature information that will be described later, and annotation content.

  If the annotation information corresponding to the acquired content is stored in the annotation DB 31, the annotation information acquisition unit 77 acquires the annotation information corresponding to the content from the annotation DB 31.

  Then, the annotation structure position acquisition unit 79 searches for the annotation structure position specified in the annotation information. The annotation embedding unit 80 embeds the annotation content at the specified position of the Web resource analysis result based on the structure position searched by the annotation structure position acquisition unit 79. The annotation restoration unit 78 can display the web page in which the annotation is restored by passing the web resource analysis result to the rendering engine.

(Composition of annotation DB)
FIG. 8 is a configuration diagram of an example of annotation information stored in the annotation DB. The annotation DB 31 in FIG. 8 has a record in which URL, XPath, feature XPath, feature information, and annotation content are associated. The ULR included in the annotation DB 31 is the URL of the content of the Web page to which the annotation has been added. XPath is the structural position on the content of the Web page to which the annotation is assigned.

  The feature XPath and the feature information are used to search the structure position on the content of the annotated Web page when the structure position on the content of the Web page annotated with the XPath cannot be specified. Is. Details of the feature XPath and feature information will be described later. The annotation content is information described in the annotation.

(Feature XPath and feature information)
FIG. 9 is an explanatory diagram for explaining the feature XPath. FIG. 9 shows an example in which the structure position on the content of the Web page with the annotation is XPath “/ HTML / BODY / TABLE”. The annotation structure position acquisition unit 75 uses the target node represented by XPath “/ HTML / BODY / TABLE” as a vertex, and extracts all XPaths up to the end.

  In the example of FIG. 9, XPath “/ TABLE / TR / TD” is extracted twice and XPath “/ TABLE / TR / TD / P” is extracted once. The annotation structure position acquisition unit 75 sets the XPath having the smallest number of appearances among the extracted XPaths as the feature XPath. In the example of FIG. 9, XPath “/ TABLE / TR / TD / P” is the characteristic XPath.

  As illustrated in FIG. 9, the annotation structure position acquisition unit 75 extracts an XPath having the smallest number of appearances among the XPaths included in the target node as a feature XPath. The reason why the XPath having the smallest number of appearances is extracted as the feature XPath is because it is considered that the feature of the target node is most representative.

  In FIG. 9, among the XPaths included in the target node, the XPath with the smallest number of appearances is extracted as the feature XPath. However, various variations such as the XPath with the largest number of appearances and the XPath with the average number of appearances are possible. .

  When using an XPath with a small number of appearances, it becomes easier to specify the reproduction position, but when the content is changed, the portion related to the feature path is likely to be changed, and the feature path is changed. Increases the possibility of not being found. When using an XPath that has a large number of appearances, it is possible to find a feature path even if the content is changed, but it is highly likely that the path is frequently used elsewhere. It becomes difficult to specify the correct reproduction position. When using an average value, it is intermediate between the above features.

  For example, in cases where it is necessary to reliably return to the correct reproduction position, such as when an annotation system is used to examine the screen configuration by a plurality of people, it is possible to provide highly accurate information by using as few feature paths. Further, in a system such as a footprint system in which it is important to notify that there is information rather than a deviation of the reproduction position, it is preferable to select a large number.

  FIG. 10 is an explanatory diagram for explaining the feature information. FIG. 10 shows an example in which the structure position on the content of the Web page with the annotation is XPath “/ HTML / BODY / TABLE”. The annotation structure position acquisition unit 75 extracts the type and number of tags included in the target node as feature information.

  In the example of FIG. 10, the tag <TABLE> is extracted once, the tag <TR> is extracted once, the tag <TD> is extracted three times, and the tag <P> is extracted once. The annotation structure position acquisition unit 75 uses the type and number of the extracted tags as feature information. The annotation structure position acquisition unit 79 also extracts feature information in the same procedure as the annotation structure position acquisition unit 75.

  FIG. 11 is an explanatory diagram showing an example in which the target node cannot be specified by XPath. The target node mentioned here is a node represented by XPath included in the annotation information.

  FIG. 11A shows content when annotation content is added. FIG. 11A is the same as the content shown in FIG. Therefore, in the content shown in FIG. 11A, the XPath included in the annotation information is “/ HTML / BODY / TABLE”. In the content shown in FIG. 11A, the feature XPath included in the annotation information is “/ TABLE / TR / TD / P”. In the content shown in FIG. 11A, the feature information included in the annotation information is “tag <TABLE> once, tag <TR> once, tag <TD> three times, tag <P> once”. .

  FIG. 11B shows content whose contents have been changed. In the content of FIG. 11B, the XPath “/ HTML / BODY / TABLE” acquired from the content before change shown in FIG. 11A does not exist. Therefore, even if the annotation structure position acquisition unit 79 searches with the XPath acquired from the content before change shown in FIG. 11A, the target node included in the content of FIG. 11B cannot be specified.

  In the system of this embodiment, the target node can be specified by performing a wild card search “// feature XPath” with the feature XPath “/ TABLE / TR / TD / P” included in the annotation information.

  In the system of the present embodiment, when the target node is specified by performing the wild card search “// feature XPath” with the feature XPath “/ TABLE / TR / TD / P”, a plurality of target nodes are specified. Sometimes. When a plurality of target nodes are specified by the wild card search “// feature XPath” using the feature XPath, one target node is specified using the feature information as shown in FIG.

  FIG. 12 is an explanatory diagram showing an example in which a plurality of target nodes are specified by a wild card search using the feature XPath. FIG. 12A is similar to FIG. 11A, and thus the description is omitted. FIG. 12B shows content whose contents have been changed. In the content of FIG. 12B, the XPath “/ HTML / BODY / TABLE” acquired from the content before the change does not exist. Therefore, even if the annotation structure position acquisition unit 79 searches with the XPath acquired from the content before the change, it cannot identify the target node included in the content of FIG.

  Therefore, the annotation structure position acquisition unit 79 performs a wild card search “// feature XPath” with the feature XPath “/ TABLE / TR / TD / P” extracted from the content before the change. I will identify.

  Therefore, the annotation structure position acquisition unit 79 extracts the types and number of tags included in the identified target nodes 100 and 101 as feature information. In the case of FIG. 12B, the target node 100 is “tag <TABLE> once, tag <TR> once, tag <TD> three times, tag <P> once”. The target node 101 is “tag <TABLE> once, tag <TR> once, tag <TD> three times, tag <P> three times”.

  The annotation structure position acquisition unit 79 compares the feature information extracted from the target nodes 100 and 101 with the feature information included in the annotation information, and has a high degree of matching with the feature information included in the annotation information, in other words, matching feature information. The target node having the highest content ratio is identified as the target node.

  In the case of FIG. 12B, the annotation structure position acquisition unit 79 can identify the target node 100 by comparing the feature information extracted from the target nodes 100 and 101 with the feature information included in the annotation information.

(Processing procedure of user terminal 10)
FIG. 13 is a flowchart of an example of the annotation assignment process. If there is an annotation assignment request for a Web page from the user, the annotation assignment unit 74 proceeds to step S1 and causes the user to select an annotation assignment position by a mouse operation on the browser 11. In step S <b> 2, the annotation assigning unit 74 causes the user to input a comment that is an annotation content by, for example, a keyboard operation on the browser 11.

  In step S3, the annotation structure position acquisition unit 75 acquires the XPath of the annotation assignment position (target node). In step S4, the annotation structure position acquisition unit 75 extracts all XPaths up to the end with the target node as a vertex.

  In step S5, the annotation structure position acquisition unit 75 extracts the XPath having the smallest number of appearances among the XPaths extracted in step S4 as the feature XPath. In step S6, the annotation structure position acquisition unit 75 extracts the type and number (number of appearances) of tags included in the annotation attachment position as feature information.

  In step S7, the annotation information storage unit 73 stores the XPath, the feature XPath, the feature information, and the annotation content in the annotation DB 31 as annotation information. In step S8, the annotation embedding unit 76 embeds the annotation content at the specified position of the Web resource analysis result of the content based on the XPath acquired by the annotation structure position acquisition unit 75 in step S3.

  Thereafter, the annotation assigning unit 74 can display the Web page of the content to which the annotation is added by passing the Web resource analysis result in which the annotation content is embedded to the rendering engine.

  FIG. 14 is a flowchart of an example of the annotation restoration process. For example, when the user designates the URL of the Web page by a keyboard operation on the browser 11, the Web resource acquisition unit 71 proceeds to Step S <b> 11 and acquires the URL of the Web page from the browser 11.

  The Web resource acquisition unit 71 acquires content corresponding to the Web page with the acquired URL from the content server 20. The Web resource analysis result preparation unit 72 holds a tree structure as a result of parsing the acquired content as a Web resource analysis result.

  In step S12, the annotation information acquisition unit 77 acquires annotation information corresponding to the URL acquired in step S11 from the annotation DB 31. In step S13, the annotation structure position acquisition unit 79 searches for a restoration position (target node) using XPath included in the annotation information.

  In step S14, the annotation structure position acquisition unit 79 proceeds to step S20 if the restoration position can be identified by the search in step S13, and embeds the annotation content at the designated position in the Web resource analysis result based on the identified restoration position.

  In step S14, the annotation structure position acquisition unit 79 proceeds to step S15 if the restoration position cannot be specified by the search in step S13, and performs a wildcard search of the restoration position using the feature XPath included in the annotation information.

  In step S16, the annotation structure position acquisition unit 79 proceeds to step S20 if the restoration position can be identified by the wild card search in step S15, and embeds the annotation content at the designated position in the Web resource analysis result based on the identified restoration position. .

  In step S16, the annotation structure position acquisition unit 79 identifies a plurality of restoration positions by the wild card search in step S15. If one restoration position cannot be identified, the process proceeds to step S17, and each of the plurality of identified restoration positions is determined. The number of appearances for each tag included in the restoration position is extracted as feature information. The annotation structure position acquisition unit 79 compares the feature information extracted in step S17 with the specific information included in the annotation information, and among the feature information extracted in step S17, specific information that matches the specific information included in the annotation information. If it can be specified, the process proceeds to step S20.

  Based on the identified restoration position, the annotation structure position acquisition unit 79 embeds the annotation content at the designated position of the Web resource analysis result. If the annotation structure position acquisition unit 79 cannot identify the specific information that matches the specific information included in the annotation information among the characteristic information extracted in step S17, the process proceeds to step S19, and the feature information included in the annotation information Specific information having the highest degree of coincidence, in other words, having the highest content ratio of the matching feature information is specified.

  Progressing to step S20 following step S19, the annotation structure position acquisition unit 79 embeds the annotation content at the specified position of the Web resource analysis result based on the specified restoration position.

  Thereafter, the annotation restoration unit 78 can display the Web page with the annotation by passing the Web resource analysis result in which the annotation content is embedded to the rendering engine.

(An example in which the annotation program is applied to the browser 11)
FIG. 15 is a configuration diagram of an example of a browser to which the annotation program of this embodiment is applied. The browser 200 in FIG. 15 shows a typical configuration, and details such as CSS processing and PDF plug-in that are unnecessary for the description are omitted.

  The HTML parser 201 analyzes the HTML document 150 received via the network, and generates a tree structure (DOM tree) 202. At the same time, the JavaScript (registered trademark) engine 206 executes the JavaScript program 205 in the HTML document 150 and rewrites the contents of the DOM tree 202. The rewritten DOM tree 202 is sent to the rendering engine 203.

  The rendering engine 203 converts the received DOM tree 202 into a form that can be seen on the screen. Then, the Java engine 206 rewrites the DOM tree 202 and changes the contents to be displayed by a user operation or the like via the user interface 204.

  The annotation program 210 is typically held in the browser 200 (ie, implemented in a form that is incorporated into the browser 200 or added as a function extension).

  Then, in addition to the Javascript program 205 of the read HTML document 150 being executed, the annotation program 210 is executed and rewrites the DOM tree 202. Note that data such as the annotation DB referred to by the annotation program 210 is held outside the browser 200.

  As another embodiment for holding the annotation program 210, it is conceivable to hold the annotation program 210 in a read HTML document. In this embodiment, the applicable Web pages are limited, but the same effect as that in which the annotation program 210 is held in the browser 200 can be provided.

  The present invention is not limited to the specifically disclosed embodiments, and various modifications and changes can be made without departing from the scope of the claims.

DESCRIPTION OF SYMBOLS 1 Annotation 10 User terminal 11 Browser 12 Plug-in 20 Content server 21 Content 22 Script 30 Annotation information management server 31 Annotation DB
DESCRIPTION OF SYMBOLS 50 Network 61 Input device 62 Output device 63 Drive device 64 Auxiliary storage device 65 Main storage device 66 Arithmetic processing device 67 Interface device 68 Recording medium 71 Web resource acquisition part 72 Web resource analysis result preparation part 73 Annotation information storage part 74 Annotation provision part 75 Annotation structure position acquisition unit 76 Annotation embedding unit 77 Annotation information acquisition unit 78 Annotation restoration unit 79 Annotation structure position acquisition unit 80 Annotation embedding unit 100, 101 Target node 150 HTML document 200 Browser 201 HTML parser 202 DOM tree 203 Rendering engine 204 User Interface 205 Javascript program 206 Javascript engine 2 0 annotation program

Claims (4)

Annotation restoration method,
On the computer,
When annotating for any position on the content having the structure, the process of storing information stored in the storage information and the lower structure of the upper side of the structure of the position in the content in association with the annotation,
Based on the storage information of the structure on the upper side of the position where the annotation is assigned to the content, it is not possible to detect that the content that matches the stored structure on the upper side is included in the content to be restored. Based on the storage information of the structure on the lower side of the position where the annotation is added, the content to be restored is detected whether the structure matching the stored structure on the lower side is included and stored. wherein when detecting that includes structure that matches the lower side of the structure, to execute a process of outputting the annotation in association with the position,
Structure of the lower side of the position to be stored, annotated restore wherein the structure der Rukoto for one path selected in accordance with the frequency of occurrence from among a plurality of paths of the lower side of the position. The annotation addition / restoration according to claim 1, wherein the stored structure on the lower side of the position is a structure related to one path having the lowest appearance frequency among a plurality of paths on the lower side of the position. Method. 2. The annotation addition / restoration method according to claim 1, wherein the stored structure on the lower side of the position is one of tree structures having the position as a vertex. When annotating for any position on the content having the structure, and stores the information stored in the storage information and the lower structure of the upper side of the structure of the position in the content storage unit in association with the annotation and means,
Based on the storage information of the structure on the upper side of the position where the annotation is assigned to the content, it is not possible to detect that the content that matches the stored structure on the upper side is included in the content to be restored. Based on the storage information of the structure on the lower side of the position where the annotation is added, the content to be restored is detected whether the structure matching the stored structure on the lower side is included and stored. And a means for controlling to output an annotation to the display unit in association with the position when it is detected that a structure that matches the structure on the lower side is included ,
The annotation addition / restoration device according to claim 1, wherein the stored structure on the lower side of the position is a structure related to one path selected according to the appearance frequency from a plurality of paths on the lower side of the position .

Images