KR101928923B1 - Method for recording a shared screen based on actions and apparatus for the same - Google Patents

Abstract

According to the present invention, a method for recording a shared screen based on an action comprises the steps of: providing a video call screen to a plurality of users; providing a shared screen capable of displaying one document separated from the video call screen; reflecting and displaying document control contents performed by at least one user among the plurality of users based on the displayed document; and recording a shared screen on which the document control contents is reflected in real time. Recording the shared screen is performed based on action information generated based on the document control contents of the at least one user.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for recording an action-

The present invention relates to an action-based shared screen recording method and apparatus therefor. More particularly, the present invention relates to a method and apparatus for reducing the amount of data of a recorded image by recording a scene shared by a video call, a video conference, and an online meeting in which two or more persons participate, based on an action.

With the advancement of the Internet and communication technologies, solutions and applications related to video calls, video conferences, online conferences, electronic conferences, etc. are becoming increasingly diverse, and some solutions and applications require users, And provides a screen sharing function for sharing the displayed screen. In addition, it is possible to provide supplementary explanation or information to a shared data screen by providing a book form function so that a user can write various drawings, lines, and writings on a screen shared with a shared screen.

In order to provide a function of re-checking the contents of a shared screen and a contents provided to users participating in a call or a conference, a shared screen must be recorded together with the contents of the contents of the book. In this case, when a shared screen is captured as it is, a large-capacity data of about 700 MB or more per hour is required to be stored. Therefore, a new recording method of storing such shared screen recording as a smaller capacity image Is required. In addition, there is a demand for a new recording method for moving to a midpoint of an image desired to be played by a user at the time of playback of the recorded shared screen and playing back the same.

(Patent Document 1) Korean Patent Publication No. 10-2017-0038614

The present invention provides a method and apparatus for reducing the amount of data of a recorded image by recording a screen shared by two or more people in a video call, a video conference, an online meeting, etc. based on an action related to the operation contents of the user .

In addition, the present invention records video information on the basis of action information generated on a shared screen as compared with the conventional method of capturing a screen several times per second and combining the captured screens to generate a recorded video, And to provide a method and an apparatus capable of expressing the present invention.

In addition, the present invention utilizes patch information generated based on a plurality of action information between predetermined time intervals in order to move to a midpoint of an image desired to be reproduced by a user at the time of reproduction of a recorded shared screen And to provide a shared screen recording and playback method capable of quickly calculating the state of a recorded image at a specific point in time.

The present invention has been made in view of the above problems,

According to an embodiment of the present invention, there is provided an action-based shared screen recording method comprising: providing a plurality of users with a video call screen; Providing a shared screen capable of displaying one or more documents separately from the video call screen; Reflecting the document manipulation contents performed by at least one user of the plurality of users based on the displayed document; And recording the shared screen reflecting the contents of the document manipulation in real time, wherein the recording of the shared screen is performed based on action information generated based on the document manipulation contents of the at least one user A shared screen recording method can be provided.

Here, the document manipulation contents may include at least one of line drawing, drawing of a figure, highlighting, movement of a screen, enlargement and reduction of a screen, and the like. In addition, the action information may include type information related to the type of document operation, target information related to an object to which the document operation is applied, payload information including specific contents of the document operation, And timestamp information including time information generated. In addition, the type information may include at least one of add, delete, and change. The target information may include at least one of a page, a line, a point, a text box, a graphic, a link, and a shared screen board of the document. can do.

In addition, the action-based shared screen recording method may further include generating patch information based on the action information on the basis of the starting point and the end point at predetermined time intervals, And the patch information may include time stamp information.

Here, the patch information may not include action information related to a newly added and deleted object between the start time and the end time within the predetermined time interval. The patch information may include only action information reflecting only the final value due to the change when there is an object changed between the start time and the end time within the predetermined time interval.

The method may further include using the patch information for reproduction at a desired point in time of reproduction of the recorded shared screen.

According to another embodiment of the present invention, there is provided an action-based shared screen recording apparatus, comprising: a video call providing unit configured to provide a video call screen to a plurality of users; A shared screen providing unit configured to provide a shared screen capable of displaying one or more documents separately from the video call screen; A user input receiving unit configured to receive document manipulation contents performed by at least one user of the plurality of users based on the displayed document; And a shared screen recording unit configured to record a shared screen in which the content of the document operation is reflected in real time, wherein the shared screen recording unit includes an action information generating unit, and the recording of the shared screen is performed on the document operation content of the at least one user And the action information is generated based on action information generated by the action information generation unit based on the action information.

Here, the document manipulation contents may include at least one of line drawing, drawing of a figure, highlighting, movement of a screen, enlargement and reduction of a screen, and the like. In addition, the action information may include type information related to the type of document operation, target information related to an object to which the document operation is applied, payload information including specific contents of the document operation, And timestamp information including time information generated. In addition, the type information may include at least one of add, delete, and change. The target information may include at least one of a page, a line, a point, a text box, a graphic, a link, and a shared screen board of the document. can do.

The shared screen recording unit may further include a patch information generation unit configured to generate patch information based on the action information on the changed document operation contents based on the start time and the end time at predetermined time intervals , The patch information may include time stamp information.

Here, the patch information may not include action information related to a newly added and deleted object between the start time and the end time within the predetermined time interval. The patch information may include only action information reflecting only the final value due to the change when there is an object changed between the start time and the end time within the predetermined time interval.

The apparatus may further include a shared screen reproducing unit configured to reproduce the recorded shared screen, and the shared screen reproducing unit may use the patch information for reproduction at a desired point in time.

According to the present invention, there is provided a method and apparatus for reducing the amount of data of a recorded image by recording a screen shared by a video call, a video conference, and an online meeting in which two or more persons participate, based on an action related to a user's operation content Can be provided.

According to the present invention, video information is recorded on the basis of action information generated on a shared screen as compared with a conventional method of capturing dozens of screens every second and combining the captured screens to generate a recorded video, It is possible to provide a method and an apparatus capable of expressing an image.

In addition, according to the present invention, in order to move to a midpoint of an image desired to be played by a user at the time of playback of a recorded shared screen, patch information generated based on a plurality of action information between predetermined time intervals It is possible to provide a shared screen recording and playback method capable of quickly calculating a state of a recorded image at a specific time point.

The effects of the present invention are not limited to those mentioned above, and other effects not mentioned may be clearly understood by those skilled in the art from the following description.

1 is a block diagram illustrating a configuration of an action-based shared screen recording apparatus according to an embodiment of the present invention.
FIGS. 2A and 2B are views illustrating an action-based shared screen recording screen according to an embodiment of the present invention.
FIG. 3 is a flowchart illustrating an action-based shared screen recording method according to an embodiment of the present invention.
FIG. 4 is a diagram for explaining a method of recording a line drawing screen according to an embodiment of the present invention.
5 is a diagram for explaining a method of recording a scene in which a screen is enlarged according to an embodiment of the present invention.
6A is a code including a plurality of action information for creating a patch according to an embodiment of the present invention.
6B is a code showing patch information generated according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

The terminology used herein is for the purpose of illustrating embodiments and is not intended to be limiting of the present invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification.

The terms " comprises, "" comprising, " " comprising, " or " comprising ", when used in this application, specify the presence or absence of one or more other components, steps, operations and / Do not exclude the addition.

Furthermore, terms including ordinals such as first, second, etc. used in the present invention can be used to describe elements, but the elements should not be limited by terms. These terms are used only for the purpose of distinguishing one component from another. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

In addition, the components shown in the embodiments of the present invention are shown independently to represent different characteristic functions, and do not mean that the components are composed of separate hardware or software constituent units. That is, each constituent unit is described by arranging each constituent unit for convenience of explanation, and at least two constituent units of each constituent unit may be combined to form one constituent unit or one constituent unit may be divided into a plurality of constituent units to perform a function. The integrated embodiments and the separate embodiments of each of these components are also included in the scope of the present invention without departing from the essence of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The configuration of the present invention and the operation and effect thereof will be clearly understood through the following detailed description.

1 is a block diagram illustrating a configuration of an action-based shared screen recording apparatus according to an embodiment of the present invention.

The shared screen recording apparatus 100 is a device capable of executing a software program or application related to a video call, a video conference, an online conference, an electronic conference, etc., and receives various data via a wired / wireless communication network And may be a terminal capable of processing, displaying, and displaying information. For example, the shared screen recording apparatus 100 may be a smart phone, a tablet computer, a desktop computer, a laptop computer, a notebook, a workstation, a personal digital assistant (PDA) ), A portable computer, a wireless phone, a mobile phone, an e-book, a portable multimedia player (PMP), a portable game machine, a digital camera, a television television, a wearable device, an AI (artificial intelligence) speaker, and the like.

The shared screen recording apparatus 100 includes a video call providing unit 110, a shared screen providing unit 120, a user input receiving unit 130, a shared screen recording unit 140, a shared screen storage unit 150, And may include a screen reproducing unit 160.

The video call provider 110 may be configured to provide a video call screen to a plurality of users for video calls, video conferences, online conferences, electronic conferences, and the like. A video call screen may be provided to two or more users participating in a video call or a conference by the video call provider 110. [

The shared screen providing unit 120 may be configured to provide a shared screen capable of displaying content desired to be shared, such as one or more documents, apart from the video call screen. Various types of contents such as documents, presentation materials, web pages, contracts, videos, and the like can be displayed on the shared screen, and operations such as the user's writing can be reflected in real time and displayed on the contents. For example, at least a part of the plurality of users can perform the writing with the document displayed on the shared screen as a background, and can perform at least one of drawing, drawing, highlighting, moving the screen, And the result can be displayed and shared on the user's screen in real time.

The user input receiving unit 130 is configured to receive document operation contents performed by at least one user among a plurality of users based on the contents provided on the shared screen. The user input receiving unit 130 is a component for receiving various inputs from a user in various ways and includes a keyboard, a touch pad, a touch screen, a key pad, a dome switch ), A physical button, a jog shuttle, and a sensor, microphone, and the like.

The shared screen recording unit 140 may be configured to record a shared screen reflecting operations of users in real time. The shared screen recording unit 140 includes an action information generating unit 141. The shared screen recording is performed by the action information generating unit 141 based on the operation contents of at least one user . ≪ / RTI >

The action information includes, for example, type information related to the type of document manipulation, target information related to the target to which the document manipulation is applied, payload information including specific contents of the manipulation of the document, Time stamp information including time information, and the like.

More specifically, the type information may include content related to the type of manipulation action, such as add, delete, change, and the like. Here, an add is used to add a sub-entity to an entity. For example, adding a point to a line occurs when performing an operation of drawing a line . Deletion is used when deleting a sub-entity of an entity, for example, when performing an operation of erasing a line on a page. Next, a change is used when changing the value of an entity, for example, when a scale of a page is changed, that is, when an operation to enlarge or reduce the page is performed.

Here, an entity is a basic unit to which a user's operation is applied, for example, a page, a line, a point, a text box, a graphic, a link, board, and the like, and all the elements displayed to the user can be viewed as entities, and the state or the appearance of the entity can be changed as the action is applied to the entity.

Next, the destination (target) information that the action means the entity to be applied, for example, "Do adding point (point) in line 1." The line 1 and the destination in the "scale of page 2 (scale) Change to 1.5 "in page 2.

Next, the payload information is concrete data contained in the corresponding action, and add " point (15, 16) to line 1" . "," Change the scale of page2 to 1.5. &Quot; and the like.

Lastly, the timestamp information may be time information in which the action occurred, and may be time information digitized according to a predetermined criterion.

Specifically, an example of the action information includes "add: type: Add", target: "line1", payload: "point1", timestamp: 1578 "includes adding point1 to line1 at time stamp 1578 , "Type: 'Change', target: 'page1', payload: 'scale, 0.6', timestamp: 1603" includes the content of changing the scale of page1 to 0.6 at time stamp 1603, , target: 'page2', payload: 'line1', timestamp: 1780 "contains the content of removing line1 from page2 at time stamp 1780, 'value, the purpose of this document is,' timestamp: 1850 'contains the content of changing the contents of textbox1 to' the purpose of this document 'at time stamp 1850.

The shared screen recording unit 140 may also generate patch information configured to generate patch information based on the action information on the basis of the starting point and the end point at predetermined time intervals, (142). ≪ / RTI >

The patch information generated by the patch information generation unit 142 is generated every predetermined time unit and includes time stamp information in the same manner as the action information. In addition, the patch information is not a set of simple action information, but includes information related to the start and end of state change in a corresponding section by compressing action information, and records only the changed state change between the start time and the end time Data storage unit.

For example, the patch information is newly added between the start time and the end time within a predetermined time interval, and does not include the action information related to the deleted object. Also, between the start time and the end time within a predetermined time interval, When there is a changed object, only the action information reflecting only the final value due to the change is included. Thus, the patch information stores only the changed contents at the start and end points. A method of generating more specific patch information will be described with reference to Figs. 6A and 6B.

The shared screen storage unit 150 is configured to store the recorded shared screen image and may be configured with a memory capable of storing a command program or data related to the shared screen recording. The shared screen storage unit 150 stores not only the shared screen image recorded through the shared screen recording unit 140 but also the action information generated by the action information generation unit 141 and the patch information generated by the patch information generation unit 142 Can be stored.

In addition, necessary data and programs from other components such as the shared-screen recording unit 140 and the shared-screen playback unit 160 can be loaded from the shared-screen storage unit 150. [

Finally, the shared screen reproducing unit 160 is configured to reproduce the recorded shared screen, and the shared screen reproducing unit 160 can use the patch information generated by the patch information generating unit 142 for reproduction at a desired point in time have.

For example, when a 4-minute recording image is reproduced, when the user wants to reproduce from the 2-minute point, not the beginning, the user can reproduce the recorded image from a desired point in time. At this time, if there is no patch information, all the actions from the start to the 2 minute time point for the image reproduction from the 2 minutes time point should be applied. However, according to the present invention, since the patch information is generated at regular intervals, By fetching the patch information, it is possible to quickly move to a desired point in time. In addition, by using the patch information at the time of reproducing the recorded image, it is possible to reduce computing resources and wastes, and significantly increase the reactivity.

FIGS. 2A and 2B are views illustrating an action-based shared screen recording screen according to an embodiment of the present invention.

Referring to FIG. 2A, the video call screen 210 may be displayed in real time together with related functions. At least two participants may be displayed on the video call screen 210, and the video call screen 210 may be deactivated when it is not necessary to display the participant's state as necessary. At this time, only the voice of the participants may be provided without displaying the call image screen of the participants.

In one example, a shared content menu screen 220 may be provided below the video call screen 210 to allow the user to load, select, and change content desired to be screen-shared. For example, a document such as a PDF, a word, or a Hangul file can be loaded through the shared content menu screen 220, a selected document can be selected, and the corresponding document can be displayed to perform screen sharing.

The content sharing screen 230 in which the selected content is displayed and shared may include a content display unit 231 for displaying the content and a content manipulation unit 232 for performing a function for the user to manipulate the content.

For example, through the content manipulation unit 232, the user can move the screen, enlarge / reduce the screen, load new content, move the document, scroll the document, draw a line in the background of the document, highlight, draw a figure, draw a graph, And so on. 2A, a document is shared on the content display section 231, and a line drawing 241, a highlighting 242, and a graph 243 created by some users can be displayed and shared together on a document, A shared screen in which the contents of the user's operation are reflected on the same content as the document to be shared can be provided in real time and the shared screen image can be recorded.

FIG. 2B shows a state in which the document screen shared on the content display unit 231 of FIG. 2A is reduced and moved down. In the content display unit 231 of FIG. 2B, Only the line drawing 241, highlighting 242 and line drawing 241 in the graph 243 shown in FIG. 2A are shown.

Such a shared screen recording screen may be variously modified and applied to a user to conveniently provide a function of loading contents for sharing and manipulating and changing the contents.

FIG. 3 is a flowchart illustrating an action-based shared screen recording method according to an embodiment of the present invention.

(S310). At this time, if the video call screen is not needed, only the voice of the participants may be provided without displaying the video call screen of the users.

(S320). If there is content such as a document to be shared by the users who participated in the video call, a sharing screen for displaying such content may be provided to the participating users It can be provided with a video call screen.

The content manipulation performed by at least one user may be reflected and displayed on the shared screen provided to a plurality of users (S330). Contents changed in the content can be displayed in real time on the user's screen through line drawing, drawing of a figure, highlighting, movement of the screen, enlargement and reduction of the screen, and the shared screen displayed in this manner can be recorded .

Action information including a type, an object, a payload, and time stamp information can be generated for recording an action-based shared screen (S340). The action information related to a plurality of user manipulation contents executed on the shared screen And records a time stamp on each action, thereby recording a shared screen on an action-by-action basis.

In addition, the user information for performing the action may be included in each action information in order to classify and record the operation contents operated by each of the plurality of users on the shared screen. In this case, when the shared screen recorded on the basis of the action information is reproduced, the user information related to the action can be displayed together as needed.

In addition, it is possible to generate patch information that records only differences at predetermined time intervals (S350). [0051] The patch information containing difference information on the start and end of the state change is compressed at predetermined time intervals It is possible to calculate the changed state of the operation at a specific time point very quickly.

(S360). For example, if the shared screen is recorded as it is, a capacity of about 700 MB or more is required per time, but it may be generated based on the action information The recorded image can be stored with a capacity of about 60 MB, which is less than about 1/10, so that the amount of data can be remarkably reduced.

The recorded shared screen can be reproduced as an image by the user (S370). Based on the patch information generated at predetermined time intervals, the user can quickly move to a desired position and reproduce the image.

FIG. 4 is a diagram for explaining a method of recording a line drawing screen according to an embodiment of the present invention.

For example, according to the conventional method, assuming that a screen is captured every minute when a line is drawn and 60 frames per second is captured, 60 screens are captured every second, and the images are combined to generate a recorded image.

On the other hand, according to the present invention, for example, a time stamp is applied to actions occurring when a line is drawn, operation contents are stored in units of actions, and since the size of action information is significantly smaller than the size of the captured screen, So that it can be recorded.

For example, the action information related to such a line drawing is {type: addPoint, timestamp: 12, x: 34, y: 56}, {type: addPoint, timestamp: 15, x: 55, y: : addPoint, timestamp: 18, x: 88, y: 22}, {type: addPoint, timestamp: 23, x: 98, y: 23}

5 is a diagram for explaining a method of recording a scene in which a screen is enlarged according to an embodiment of the present invention.

For example, according to the conventional method, assuming that a screen is captured at every moment when a shared screen is enlarged, and 60 frames per second is captured, 60 screens are captured every second, and the images are combined to generate a recorded image.

On the other hand, according to the present invention, a time stamp is recorded on actions that occur when a screen is enlarged, and since the size of action information is significantly smaller than the size of the captured screen, .

For example, the action information related to such screen enlargement is {type: changeView, timestamp: 12, scale: 1.21}, {type: changeView, timestamp: 15, scale: 1.24} : 1.32}, {type: changeView, timestamp: 23, scale: 1.45}, and the like.

6A is a code including a plurality of action information for creating a patch according to an embodiment of the present invention

6A, we add points (point1 to point4) to line1 with respect to a to d, generate line2 on page1 with respect to e to h, and then generate points (point1 to point3 ), Deletes line 2 from page 1 in relation to i, sequentially increases the scale of page 1 to 0.6, 0.65, and 0.7 with respect to j from 1, sequentially includes action data including each timestamp information Is expressed.

6A, (1) points are added to line 1, (2) points are added after creating line 2 in page 1, (3) line 2 is deleted from page 1, (4) To 0.7.

FIG. 6B shows a generated set of actions performed within a specific time interval as patch information.

Note that when creating patch information based on a plurality of pieces of action information, line 2 does not appear in patch information because line 2 is generated in the middle of one patch and disappears. Thus, the patch information includes only the changes of the beginning and end. Also, only the final value is stored, not the intermediate process in which the scale of page 1 is changed. As described above, the patch information is a data storage unit that records only the difference, and since a plurality of action information is stored in a highly summarized manner within the corresponding time interval, the capacity can be significantly reduced.

In this way, if the patch information is generated and maintained for each time interval unit, it is possible to quickly calculate the state at a specific time. For example, there is no need to apply all the actions to the time stamps from 1578 to 1766, It is possible to perform fast forwarding or fast forwarding more efficiently.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. Should be interpreted as having the broadest range of following. Skilled artisans may implement the pattern of features that have not been explicitly described in combination, substitution of the disclosed embodiments, but which, too, do not depart from the scope of the present invention. It will be apparent to those skilled in the art that various changes and modifications may be readily made without departing from the spirit and scope of the invention as defined by the appended claims.

100: Shared screen recording device 110:
120: Shared picture providing unit 130: User input receiving unit
140: Shared screen recording unit 141: Action information generating unit
142: patch information generation unit 150: shared screen storage unit
160: Shared screen playback unit

Claims (18)

In an action-based shared screen recording method,
Providing a video call screen to a plurality of users;
Providing a shared screen capable of displaying one or more documents separately from the video call screen;
Reflecting the document manipulation contents performed by at least one user of the plurality of users based on the displayed document; And
Wherein the recording of the shared screen is performed based on action information generated based on contents of a document operation of the at least one user, step
Lt; / RTI >
The action information includes type information related to the type of document manipulation, target information related to the target to which the document manipulation is applied, payload information including specific contents of the manipulation of the document, And includes timestamp information including information,
Further comprising the step of generating patch information based on the action information of the changed document manipulation contents based on the start point and the end point at predetermined time intervals, wherein the patch information includes time stamp information Wherein the patch information includes only action information reflecting only a final value due to a change when there is an object changed between a start point and an end point within the predetermined time interval. The method according to claim 1, wherein the content of the document manipulation includes at least one of line drawing, drawing of a figure, highlighting, movement of a screen, enlargement and reduction of a screen, and the like. delete The shared screen recording method according to claim 1, wherein the type information includes at least one of add, delete, and change. 2. The method of claim 1, wherein the target information includes at least one of a page, a line, a point, a text box, a graphic, a link, and a shared screen board Wherein the shared screen recording method comprises: delete The shared-screen recording method of claim 1, wherein the patch information does not include action information related to a newly added and deleted object between a start time and an end time within the predetermined time interval. delete The shared screen recording method according to claim 1, further comprising using the patch information for reproduction at a desired point in time of reproduction of a recorded shared screen. An action-based shared screen recording apparatus,
A video call providing unit configured to provide a video call screen to a plurality of users;
A shared screen providing unit configured to provide a shared screen capable of displaying one or more documents separately from the video call screen;
A user input receiving unit configured to receive document manipulation contents performed by at least one user of the plurality of users based on the displayed document; And
A shared screen recording unit configured to record a shared screen reflecting the contents of the document operation in real time,
Lt; / RTI >
Wherein the shared-screen recording unit includes an action-information generating unit, wherein the recording of the shared screen is performed based on action information generated by the action-information generating unit based on document manipulation contents of the at least one user,
The action information includes type information related to the type of document manipulation, target information related to the target to which the document manipulation is applied, payload information including specific contents of the manipulation of the document, And includes timestamp information including information,
Wherein the shared screen recording unit further comprises a patch information generating unit configured to generate patch information based on the action information on the changed document operation contents based on the start time and the end time at predetermined time intervals, The patch information includes time stamp information and the patch information includes only action information reflecting only the final value due to the change when there is an object changed between the start time and the end time within the predetermined time interval , A shared screen recording device. The apparatus of claim 10, wherein the document manipulation contents include at least one of line drawing, drawing of a figure, highlighting, movement of a screen, enlargement and reduction of a screen, and the like. delete The apparatus of claim 10, wherein the type information includes at least one of add, delete, and change. The method of claim 10, wherein the target information includes at least one of a page, a line, a point, a text box, a graphic, a link, and a shared screen board Wherein the shared picture recording apparatus comprises at least one shared picture recording apparatus. delete The apparatus of claim 10, wherein the patch information does not include action information related to a newly added and deleted object between a start time and an end time within the predetermined time interval. delete The shared screen recording apparatus according to claim 10, further comprising a shared screen reproducing unit configured to reproduce the recorded shared screen, wherein the shared screen reproducing unit uses the patch information for reproduction at a desired point in time.

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