File page-following annotation method and system for electronic whiteboard

Abstract

The invention discloses a file page-following annotation method and system for an electronic whiteboard, and the method comprises the steps: opening a to-be-annotated file online for previewing, and converting each page of the to-be-annotated file into a picture; previewing each picture on line, obtaining a click event of a display page, constructing an annotation layer in the picture according to the click event, and recording an annotation note occurring in the annotation layer; switching operation of the display page is obtained, the annotation layer and the annotation note are stored, annotation along with the page and online previewing of the file are achieved, and the annotation requirement of a user is met.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic whiteboards, and in particular to a method and system for annotating files on electronic whiteboards. Background Art

[0002] With the development of technology, electronic whiteboards, as a new type of teaching and office tool, have gradually been widely used in various work or teaching scenarios.

[0003] Traditional electronic whiteboards usually support basic writing and drawing functions, but when processing complex documents such as PDF and PPT, their annotation functions are often limited and cannot achieve on-page annotation and real-time preview. With the increase in multimedia teaching and office needs, the demand for electronic whiteboard annotation functions is getting higher and higher. Summary of the invention

[0004] In order to solve the above technical problems, the present invention discloses a method for annotating files on an electronic whiteboard, which is used to realize on-page annotation and online preview.

[0005] In order to achieve the above object, the present invention discloses a method for annotating a document page on an electronic whiteboard, comprising:

[0006] Open the file to be annotated online for preview, and convert each page of the file to be annotated into a picture;

[0007] Preview each of the pictures online, and obtain click events of the display page, so as to construct an annotation layer in the pictures according to the click events, and record the annotation notes occurring in the annotation layer;

[0008] The switching operation of the display page is obtained, and the annotation layer and the annotation notes are saved.

[0009] The present invention discloses a method for annotating files on electronic whiteboards. First, the file to be annotated is opened online for preview. The content of the file can be viewed at any time based on the preview. Then, the file is converted into pictures one by one to complete the annotation of the file according to the format of the pictures.

[0010] During the annotation process, each of the pictures is previewed in real time, and the click operation of the display page is obtained, so as to timely monitor the user's annotation operation and annotate the picture of the current display page at any time. When annotating, a transparent annotation layer is constructed in the picture so that the transparent layer can receive the user's input annotation operation to form annotation notes without affecting the content of the picture, thereby ensuring the effect of the annotation. After monitoring the switching operation of the current display page, the annotation layer and the annotation notes are saved so that the user can view the annotation content of the corresponding page later to meet the user's annotation needs.

[0011] As a preferred example, the online opening of the file to be annotated for previewing includes:

[0012] Detecting a login operation, obtaining identity information of a user who triggers the login operation, and determining whether the user has the right to annotate a file based on the identity information;

[0013] When it is determined that the user has the right to annotate a file, the file to be annotated is obtained according to the file upload operation triggered by the user, and a preview interface corresponding to the file to be annotated is generated;

[0014] The file to be annotated is displayed according to the preview interface.

[0015] The present invention ensures that the user can make annotations and the privacy of the annotations by identifying the user's identity. After identifying the user's identity information, the user's file upload operation is received and the preview interface is generated to ensure that the user can view the content of the file in real time, thereby meeting the user's usage needs.

[0016] As a preferred example, converting each page of the to-be-annotated file into a picture includes:

[0017] Performing format analysis on the file to be annotated to determine whether the file to be annotated is in PDF format or PPT format;

[0018] When it is determined that the file to be annotated is in PDF format or PPT format, each page of the file to be annotated is obtained through a file parsing library, and each page of the content is converted into an image format to generate a plurality of continuous images corresponding to the file to be annotated.

[0019] The present invention performs format analysis on the file to be annotated, and when recognizing that the file is in PDF format or PPT format, converts the file into a picture, so as to realize the annotation of the file through the picture.

[0020] As a preferred example, the online preview of each of the pictures and obtaining a click event of the displayed page include:

[0021] Rendering a plurality of the images sequentially onto a display page of the electronic whiteboard currently logged in by the user, and displaying each of the images in the preview interface;

[0022] The click event occurring in the area where the toolbar is located in the display page is monitored in real time, so as to determine the annotation tool selected by the user according to the click event and activate the annotation tool.

[0023] The present invention displays the image on the preview interface, so that the user can view the content of the file at any time, and renders the image to the display page to facilitate the annotation operation through the display page. By real-time monitoring of click events occurring in the area where the toolbar is located in the display page, and timely responding to the user's annotation operation, the annotation recording and display of the file are realized.

[0024] As a preferred example, constructing an annotation layer in the picture according to the click event includes:

[0025] Listening to the annotation operation on the display page, and detecting whether there is an annotation layer for the picture in the current display page according to the annotation operation;

[0026] When it is detected that the annotation layer does not exist in the picture in the current display page, an annotation layer area is selected in the picture, and a pre-built transparent annotation layer is called to cover the annotation layer area.

[0027] The present invention detects whether an annotation layer exists in a picture in the display page, thereby avoiding repeated construction of the annotation layer when the picture has an annotation layer, thereby improving the efficiency of annotation.

[0028] As a preferred example, constructing an annotation layer in the picture according to the click event includes:

[0029] When it is detected that the image in the current display page has the annotation layer, the historical annotation layer and the corresponding historical annotation notes corresponding to the image are loaded;

[0030] Click the historical annotation layer to display the historical annotation notes and edit and save the historical annotation notes.

[0031] The present invention avoids repeated construction of annotation layers by calling the historical annotation layer, which not only reduces the amount of data processing and improves annotation efficiency, but also displays historical annotation notes, making it convenient for users to modify them based on the historical annotation notes to meet the user's annotation needs.

[0032] As a preferred example, the annotation notes recorded in the annotation layer include:

[0033] Monitoring the annotation operation occurring on the transparent annotation layer, and recording the starting position and operation path corresponding to the annotation operation;

[0034] According to the starting position and the operation path, combined with the annotation tool selected by the user, the annotation handwriting input by the user is displayed on the transparent annotation layer in real time.

[0035] The present invention records the user's input operation in real time through the annotation layer, and displays the annotation notes corresponding to the annotation operation, thereby realizing the on-page annotation of the electronic whiteboard.

[0036] As a preferred example, the obtaining of the switching operation of the display page and the saving of the annotation layer and the annotation note include:

[0037] Acquire the annotation adjustment operation of the currently displayed page, and adjust the style of the annotation note according to the annotation adjustment operation;

[0038] Traversing each annotation layer of the picture in the current display page according to the switching operation to extract the annotation handwriting in the annotation layer;

[0039] An association relationship between the annotation note and the picture is constructed to generate annotation information of the file to be annotated according to the association relationship.

[0040] The present invention adjusts the style of the annotation notes in real time according to the annotation adjustment operation of the displayed page, and when a page switching operation is detected, the annotation notes of the current picture are saved in real time to ensure that the annotation is not lost.

[0041] On the other hand, the present invention discloses a document page annotation system for electronic whiteboard, comprising a document conversion module, an online annotation module and a storage module;

[0042] The file conversion module is used to open the file to be annotated online for preview, and convert each page of the file to be annotated into a picture;

[0043] The online annotation module is used to preview each of the pictures online and obtain click events of the display page, so as to construct an annotation layer in the picture according to the click events and record the annotation notes occurring in the annotation layer;

[0044] The saving module is used to obtain the switching operation of the display page and save the annotation layer and the annotation notes.

[0045] The present invention discloses a file page annotation system for an electronic whiteboard. Firstly, the file to be annotated is opened online for preview. The content of the file can be viewed at any time based on the preview. Then, the file is converted into pictures one by one to complete the annotation of the file according to the format of the pictures.

[0046] During the annotation process, each of the pictures is previewed in real time, and the click operation of the display page is obtained, so as to timely monitor the user's annotation operation and annotate the picture of the current display page at any time. When annotating, a transparent annotation layer is constructed in the picture so that the transparent layer can receive the user's input annotation operation to form annotation notes without affecting the content of the picture, thereby ensuring the effect of the annotation. After monitoring the switching operation of the current display page, the annotation layer and the annotation notes are saved so that the user can view the annotation content of the corresponding page later to meet the user's annotation needs.

[0047] As a preferred example, the file conversion module includes a preview unit and a format conversion unit;

[0048] The preview unit is used to detect a login operation, obtain the identity information of the user who triggered the login operation, and determine whether the user has the right to annotate the file based on the identity information; when it is determined that the user has the right to annotate the file, obtain the file to be annotated based on the file upload operation triggered by the user, and generate a preview interface corresponding to the file to be annotated; and display the file to be annotated based on the preview interface;

[0049] The format conversion unit is used to perform format analysis on the file to be annotated, and determine whether the file to be annotated is in PDF format or PPT format;

[0050] When it is determined that the file to be annotated is in PDF format or PPT format, each page of the file to be annotated is obtained through a file parsing library, and each page of the content is converted into an image format to generate a plurality of continuous images corresponding to the file to be annotated. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 : is a flow chart of a method for annotating a document page on an electronic whiteboard disclosed in an embodiment of the present invention;

[0052] Figure 2 : is a structural schematic diagram of a file page annotation system for an electronic whiteboard disclosed in an embodiment of the present invention;

[0053] Figure 3 : A flowchart of a method for annotating a document page on an electronic whiteboard disclosed in another embodiment of the present invention. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] Embodiment 1

[0056] This embodiment discloses a method for annotating a document page on an electronic whiteboard. For the specific implementation process of the annotation method, please refer to Figure 1 , mainly including steps 101 to 103, wherein the steps are mainly:

[0057] Step 101: Open the file to be annotated online for preview, and convert each page of the file to be annotated into a picture.

[0058] In this embodiment, the steps mainly include: detecting a login operation, obtaining the identity information of the user who triggers the login operation, and judging whether the user has the right to annotate files based on the identity information; when it is judged that the user has the right to annotate files, obtaining the file to be annotated based on the file upload operation triggered by the user, and generating a preview interface corresponding to the file to be annotated; and displaying the file to be annotated based on the preview interface.

[0059] Furthermore, the format of the file to be annotated is parsed to determine whether the file to be annotated is in PDF format or PPT format; when it is determined that the file to be annotated is in PDF format or PPT format, each page of the file to be annotated is obtained through a file parsing library, and the content of each page is converted into an image format to generate a number of continuous images corresponding to the file to be annotated.

[0060] This step ensures that the user can make annotations and the privacy of the annotations by identifying the user's identity. After identifying the user's identity information, the user's file upload operation is received and the preview interface is generated to ensure that the user can view the content of the file in real time, meeting the user's usage needs. Further, by format parsing the file to be annotated, when the file is identified as PDF or PPT format, it is converted into a picture to annotate the file through the picture.

[0061] Step 102: Preview each of the pictures online and obtain click events of the display page, so as to construct an annotation layer in the picture according to the click events and record the annotation notes occurring in the annotation layer.

[0062] In this embodiment, the steps mainly include: rendering several of the pictures in sequence onto the display page of the electronic whiteboard to which the user is currently logged in, and displaying each of the pictures in the preview interface; monitoring in real time the click events occurring in the toolbar area of ​​the display page, so as to determine the annotation tool selected by the user based on the click event and activate the annotation tool.

[0063] Furthermore, the annotation operation on the display page is monitored, and based on the annotation operation, it is detected whether there is an annotation layer for the picture in the current display page; when it is detected that the annotation layer does not exist for the picture in the current display page, the annotation layer area is selected in the picture, and a pre-built transparent annotation layer is called to cover the annotation layer area; when it is detected that the annotation layer exists for the picture in the current display page, the historical annotation layer and the corresponding historical annotation notes corresponding to the picture are loaded; the historical annotation layer is clicked to display the historical annotation notes and edit and save the historical annotation notes; the annotation operation occurring on the transparent annotation layer is monitored, and the starting position and operation path corresponding to the annotation operation are recorded; based on the starting position and operation path, combined with the annotation tool selected by the user, the annotation handwriting input by the user is displayed on the transparent annotation layer in real time.

[0064] This step displays the image on the preview interface, which is convenient for users to view the content of the file at any time, and renders the image to the display page to facilitate annotation operations through the display page. By real-time monitoring of click events occurring in the area where the toolbar is located in the display page, and timely responding to the user's annotation operations, the annotation recording and display of the file is realized. Further, by detecting whether there is an annotation layer for the image in the display page, it is avoided to repeatedly construct the annotation layer when the annotation layer exists for the image, thereby improving the efficiency of annotation.

[0065] Step 103: Obtain the switching operation of the display page, and save the annotation layer and the annotation notes.

[0066] In this embodiment, the steps mainly include: obtaining the annotation adjustment operation of the currently displayed page, and adjusting the style of the annotation note according to the annotation adjustment operation; traversing each annotation layer of the picture in the currently displayed page according to the switching operation to extract the annotation notes in the annotation layer; constructing an association relationship between the annotation note and the picture to generate annotation information of the file to be annotated according to the association relationship.

[0067] This step adjusts the style of the annotation notes in real time according to the annotation adjustment operation of the displayed page. At the same time, when the page switching operation is detected, the annotation notes of the current image are saved in real time to ensure that the annotation is not lost.

[0068] On the other hand, the present invention discloses a document page annotation system for an electronic whiteboard. The specific structure of the annotation system is shown in FIG. Figure 2 , including a file conversion module 201, an online annotation module 202 and a saving module 203.

[0069] The file conversion module 201 is used to open the file to be annotated online for preview, and convert each page of the file to be annotated into a picture.

[0070] The online annotation module 202 is used to preview each of the pictures online and obtain click events of the display page, so as to construct an annotation layer in the picture according to the click events and record the annotation notes occurring in the annotation layer.

[0071] The saving module 203 is used to obtain the switching operation of the display page and save the annotation layer and the annotation notes.

[0072] In this embodiment, the file conversion module 201 includes a preview unit and a format conversion unit.

[0073] The preview unit is used to detect a login operation, obtain the identity information of the user who triggered the login operation, and determine whether the user has the right to annotate files based on the identity information; when it is determined that the user has the right to annotate files, obtain the file to be annotated based on the file upload operation triggered by the user, and generate a preview interface corresponding to the file to be annotated; and display the file to be annotated based on the preview interface.

[0074] The format conversion unit is used to perform format analysis on the file to be annotated to determine whether the file to be annotated is in PDF format or PPT format; when it is determined that the file to be annotated is in PDF format or PPT format, each page of the file to be annotated is obtained through the file analysis library, and each page of the content is converted into an image format to generate a number of continuous images corresponding to the file to be annotated.

[0075] In this embodiment, the online annotation module 202 includes a tool activation unit, an annotation layer detection unit, and an annotation recording unit.

[0076] The tool activation unit is used to render several of the pictures in sequence onto the display page of the electronic whiteboard to which the user is currently logged in, and to display each of the pictures in the preview interface; and to monitor in real time the click events occurring in the area where the toolbar is located in the display page, so as to determine the annotation tool selected by the user based on the click events and activate the annotation tool.

[0077] The annotation layer detection unit is used to monitor the annotation operation on the display page, and detect whether there is an annotation layer for the picture in the current display page according to the annotation operation; when it is detected that the annotation layer does not exist for the picture in the current display page, select the annotation layer area in the picture, and call the pre-built transparent annotation layer to cover the annotation layer area; when it is detected that the annotation layer exists for the picture in the current display page, load the historical annotation layer and the corresponding historical annotation notes corresponding to the picture; click the historical annotation layer to display the historical annotation notes and edit and save the historical annotation notes.

[0078] The annotation recording unit is used to monitor the annotation operations occurring on the transparent annotation layer, and record the starting position and operation path corresponding to the annotation operation; based on the starting position and operation path, combined with the annotation tool selected by the user, the annotation notes input by the user are displayed in real time on the transparent annotation layer.

[0079] In this embodiment, the saving module 203 includes an adjustment unit and a saving unit.

[0080] The adjustment unit is used to obtain the annotation adjustment operation of the currently displayed page, and adjust the style of the annotation note according to the annotation adjustment operation.

[0081] The saving unit is used to traverse each annotation layer of the picture in the current display page according to the switching operation to extract the annotation notes in the annotation layer; and construct an association relationship between the annotation notes and the picture to generate annotation information of the file to be annotated according to the association relationship.

[0082] The present embodiment discloses a method and system for annotating files on an electronic whiteboard. First, the file to be annotated is opened online for preview. The content of the file can be viewed at any time based on the preview. Then, the file is converted into pictures to complete the annotation of the file according to the format of the pictures.

[0083] During the annotation process, each of the pictures is previewed in real time, and the click operation of the display page is obtained, so as to timely monitor the user's annotation operation and annotate the picture of the current display page at any time. When annotating, a transparent annotation layer is constructed in the picture so that the transparent layer can receive the user's input annotation operation to form annotation notes without affecting the content of the picture, thereby ensuring the effect of the annotation. After monitoring the switching operation of the current display page, the annotation layer and the annotation notes are saved so that the user can view the annotation content of the corresponding page later to meet the user's annotation needs.

[0084] Embodiment 2

[0085] This embodiment further discloses a method for annotating a document on a page for an electronic whiteboard, wherein the annotation method can be applied to an electronic whiteboard system. In this embodiment, the specific implementation process of the electronic whiteboard system executing the method for annotating a document on a page can be referred to in Figure 3 , mainly including steps 301 to 307, the steps are mainly:

[0086] Step 301: Acquire a file uploaded by a user, and perform format verification on the file, so as to display the file on a display interface of the electronic whiteboard according to the verification result.

[0087] Specifically, in this embodiment, the identity information of the user who triggers the login operation is obtained, and whether the user has the right to annotate files is determined based on the identity information; when it is determined that the user has the right to annotate files, the file to be annotated is obtained based on the file upload operation triggered by the user, and a preview interface corresponding to the file to be annotated is generated; and the file to be annotated is displayed based on the preview interface.

[0088] Optionally, a login page is displayed on the interface of the electronic whiteboard, and a user name and password entered by the user on the login page are received. A query is performed in the database based on the user name and password to verify whether the user exists. If it is determined that the user exists, a successful login is displayed, and the user enters the main interface of the electronic whiteboard. If it is determined that the user does not exist, a prompt is given to log in again.

[0089] After the user successfully logs in, check whether the user has uploaded a file. The user can click the "Upload File" button at the same time to select a local file to upload and store. If the upload is successful, the file preview will be displayed. If it fails, it will prompt to upload again.

[0090] Specifically, after the file is successfully uploaded, the format of the file to be annotated is parsed to determine whether the file to be annotated is in PDF format or PPT format; when it is determined that the file to be annotated is in PDF format or PPT format, each page of the file to be annotated is obtained through a file parsing library, and the content of each page is converted into an image format to generate a number of continuous images corresponding to the file to be annotated.

[0091] Optionally, the electronic whiteboard system calls the parsing module to convert the file content into a format that can be turned over and displayed. For PDF files: use a PDF parsing library (such as PyMuPDF or PDFMiner) to read the file content, extract the image or text of each page, and convert it to an image format (such as PNG or JPEG). For PPT files: use a PPT parsing library (such as python-pptx) to read the PPT file. Extract the content of each page of the slide and convert it to an image format. During the parsing process, check whether the file is parsed successfully and display the parsing process through a progress bar.

[0092] The system traverses the generated image files, uses an image rendering library (such as Pillow) to load and display each page of the image on the electronic whiteboard interface. Further, the system renders the parsed first page content to the electronic whiteboard interface to check whether the file content is displayed correctly.

[0093] Step 302: Initialize the annotation tool and detect whether there is an annotation layer in the picture in the current display interface, so as to create the annotation layer in each picture according to the detection result.

[0094] Specifically, in this embodiment, several of the pictures are rendered in sequence onto the display page of the electronic whiteboard to which the user is currently logged in, and each of the pictures is displayed in the preview interface; click events occurring in the toolbar area of ​​the display page are monitored in real time to determine the annotation tool selected by the user based on the click event and activate the annotation tool.

[0095] Optionally, an event listener is set for each annotation tool in the toolbar. The listener monitors the user's click event, records the type of tool clicked (such as a brush, a highlighter), and calls the corresponding annotation tool module according to the recorded tool type. The annotation tool is activated and is ready to receive the user's annotation operation. Further, it is determined whether the user has selected the annotation tool based on the listener, and the annotation tool (such as a brush, a highlighter) selected by the user from the toolbar is determined. The selected annotation tool is activated and displayed on the screen.

[0096] Optionally, after activating the annotation tool, detect whether there is an annotation layer on the page in the current display interface. If not, create a transparent annotation layer on the current page. Further, use HTML5 Canvas or SVG elements to create a new transparent layer on the page, covering the file content. Set the size and position of the annotation layer to align it with the page content. Initialize the properties of the annotation layer, such as background transparency, drawable area, etc. After the annotation layer is successfully created, the user can make annotations. The annotation layer is displayed superimposed on the file content.

[0097] If the image has an annotation layer, the annotation layer is loaded and displayed on the page content.

[0098] Step 303: Record the annotation operation occurring in the annotation layer, and generate annotation content corresponding to the annotation operation.

[0099] Specifically, in this embodiment, the annotation operation occurring on the transparent annotation layer is monitored, and the starting position and operation path corresponding to the annotation operation are recorded; based on the starting position and operation path, combined with the annotation tool selected by the user, the annotation notes input by the user are displayed on the transparent annotation layer in real time.

[0100] Optionally, detect whether the user is operating on the annotation layer. If an operation is detected, the user's annotation operation is recorded, including information such as position, color, size, etc., and the annotation is displayed in real time on the annotation layer. Among them, the annotation tool responds to user input and updates the display in real time. Furthermore, the system monitors mouse or touch events (such as mousedown, mousemove, mouseup) on the annotation layer. When the user presses the mouse or touches the screen, the starting position is recorded. When the user moves the mouse or finger, the path is recorded and the real-time effect is drawn. When the user releases the mouse or touches the screen, the end position is recorded and the drawing is completed. The data of the annotation operation is saved, including coordinates, color, thickness, timestamp, etc.

[0101] Step 304: Acquire a switching operation occurring in the display interface, and save the annotation content according to the switching operation.

[0102] Specifically, it is determined whether the user has performed a page turning operation. When the user clicks the "previous page" or "next page" button, the system loads the corresponding page. After the page is turned successfully, the new page is displayed and the corresponding annotation layer is loaded. Among them, the page turning button interaction is set, and the page content and the annotation layer are updated synchronously. Furthermore, when the system loads a new page, it checks whether the target page already has an annotation layer. If so, the annotation layer is loaded and displayed on the new page content. If not, a new transparent annotation layer is created.

[0103] Optionally, the system is set to enable an automatic save function, wherein the system automatically saves the user's annotation content periodically and notifies the user when the automatic save is successful.

[0104] Step 305: Acquire annotation layer management operations and management operations occurring in the display interface, and adjust the annotation layer and export annotation files.

[0105] Specifically, the system loads the real-time preview. When the user enables the real-time preview function, the user's annotation operation is sent to the preview module in real time, and the preview window is updated in real time.

[0106] Optionally, the system sets a save button to determine whether the user chooses to save the annotation. When the user clicks the "Save" button, the system saves the annotation information together with the page content, and prompts the user if the saving is successful, and prompts the user to try again if it fails.

[0107] Optionally, the system sets an export button, and when the user clicks the "Export" button, the system generates a PDF or PPT file containing annotations, and prompts the user if the export is successful, and prompts the user to try again if it fails.

[0108] Optionally, before the user clicks the "Export" button, the user can choose to edit, delete or hide the annotation layer. The annotation layer management operation is successful and the interface is updated. Furthermore, the editing of the annotation layer includes the user being able to choose to modify the color, thickness and other parameters of the annotation to adjust the annotation style. The style adjustment takes effect immediately after it is successful.

[0109] Step 306: Acquire a page adjustment operation input by the user to adjust the display interface of the electronic whiteboard.

[0110] Specifically, the user zooms in or out or moves the page through gestures or buttons, and the page display is adjusted according to the real-time feedback of the user operation.

[0111] Step 307: Obtain the annotation search operation or login / logout operation input by the user to search the annotation content and save the file.

[0112] Specifically, the system records each annotation operation of the user and makes it available for the user to view. After the record is successful, the system will display the successful history record. The user can enter the search keyword, and the system will search for matching content in all annotations. When the corresponding annotation content is retrieved, the search result will be highlighted.

[0113] Optionally, the system sets a "Logout" button. When the user clicks the "Logout" button, the system records the user status and logs out safely. At the same time, the system returns to the login interface after the user successfully logs out.

[0114] Furthermore, before the user performs an exit operation, the system automatically saves the user's annotation content regularly to form the annotation content corresponding to the file, and automatically prompts the user that the saving is successful.

[0115] Optionally, during the entire process of the user logging into the system to annotate files, the system performs real-time anomaly detection, and after detecting an anomaly (such as network interruption, file damage, etc.), prompts the user to handle the anomaly and attempts to recover from the anomaly. The user is prompted when the anomaly is successfully handled.

[0116] The present embodiment discloses a method for annotating files on a page for an electronic whiteboard, which supports annotating files on a page in PDF and PPT files and has a real-time preview function. The annotations are displayed in a superimposed manner through a transparent annotation layer, and the user can view the annotation content of the corresponding page when turning the page of the file.

[0117] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. It is particularly pointed out that for those skilled in the art, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for annotating a document page on an electronic whiteboard, characterized in that: include: Open the file to be annotated online for preview, and convert each page of the file to be annotated into a picture; Preview each of the pictures online, and obtain click events of the display page, so as to construct an annotation layer in the pictures according to the click events, and record the annotation notes occurring in the annotation layer; The switching operation of the display page is obtained, and the annotation layer and the annotation notes are saved.

2. A method for annotating a document page on an electronic whiteboard according to claim 1, characterized in that: The online opening of the file to be annotated for previewing includes: Detecting a login operation, obtaining identity information of a user who triggers the login operation, and determining whether the user has the right to annotate a file based on the identity information; When it is determined that the user has the right to annotate a file, the file to be annotated is obtained according to the file upload operation triggered by the user, and a preview interface corresponding to the file to be annotated is generated; The file to be annotated is displayed according to the preview interface.

3. The method for annotating a document page on an electronic whiteboard according to claim 1, characterized in that: The step of converting each page of the document to be annotated into a picture includes: Performing format analysis on the file to be annotated to determine whether the file to be annotated is in PDF format or PPT format; When it is determined that the file to be annotated is in PDF format or PPT format, each page of the file to be annotated is obtained through a file parsing library, and each page of the content is converted into an image format to generate a plurality of continuous images corresponding to the file to be annotated.

4. The method for annotating a document page on an electronic whiteboard according to claim 2, characterized in that: The online preview of each of the pictures and obtaining the click event of the displayed page include: Rendering a plurality of the images sequentially onto a display page of the electronic whiteboard currently logged in by the user, and displaying each of the images in the preview interface; The click event occurring in the area where the toolbar is located in the display page is monitored in real time, so as to determine the annotation tool selected by the user according to the click event and activate the annotation tool.

5. A method for annotating a document page on an electronic whiteboard according to claim 4, characterized in that: The step of constructing an annotation layer in the picture according to the click event includes: Listening to the annotation operation on the display page, and detecting whether there is an annotation layer for the picture in the current display page according to the annotation operation; When it is detected that the annotation layer does not exist in the picture in the current display page, an annotation layer area is selected in the picture, and a pre-built transparent annotation layer is called to cover the annotation layer area.

6. A method for annotating a document page on an electronic whiteboard according to claim 5, characterized in that: The step of constructing an annotation layer in the picture according to the click event includes: When it is detected that the image in the current display page has the annotation layer, the historical annotation layer and the corresponding historical annotation notes corresponding to the image are loaded; Click the historical annotation layer to display the historical annotation notes and edit and save the historical annotation notes.

7. The method for annotating a document page on an electronic whiteboard according to claim 5, characterized in that: The annotation notes recorded in the annotation layer include: Monitoring the annotation operation occurring on the transparent annotation layer, and recording the starting position and operation path corresponding to the annotation operation; According to the starting position and the operation path, combined with the annotation tool selected by the user, the annotation handwriting input by the user is displayed on the transparent annotation layer in real time.

8. The method for annotating a document page on an electronic whiteboard according to claim 1, characterized in that: The obtaining of the switching operation of the display page and saving the annotation layer and the annotation notes include: Acquire the annotation adjustment operation of the currently displayed page, and adjust the style of the annotation note according to the annotation adjustment operation; Traversing each annotation layer of the picture in the current display page according to the switching operation to extract the annotation handwriting in the annotation layer; An association relationship between the annotation note and the picture is constructed to generate annotation information of the file to be annotated according to the association relationship.

9. A document page annotation system for electronic whiteboard, characterized in that: Including file conversion module, online annotation module and saving module; The file conversion module is used to open the file to be annotated online for preview, and convert each page of the file to be annotated into a picture; The online annotation module is used to preview each of the pictures online and obtain click events of the display page, so as to construct an annotation layer in the picture according to the click events and record the annotation notes occurring in the annotation layer; The saving module is used to obtain the switching operation of the display page and save the annotation layer and the annotation notes.

10. The method for annotating a document page on an electronic whiteboard according to claim 9, characterized in that: The file conversion module includes a preview unit and a format conversion unit; The preview unit is used to detect a login operation, obtain identity information of a user who triggers the login operation, and determine whether the user has the right to annotate a file based on the identity information; When it is determined that the user has the right to annotate a file, the file to be annotated is obtained according to the file upload operation triggered by the user, and a preview interface corresponding to the file to be annotated is generated; Displaying the file to be annotated according to the preview interface; The format conversion unit is used to perform format analysis on the file to be annotated to determine whether the file to be annotated is in PDF format or PPT format; when it is determined that the file to be annotated is in PDF format or PPT format, each page of the file to be annotated is obtained through the file analysis library, and each page of the content is converted into an image format to generate a number of continuous images corresponding to the file to be annotated.

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