KR100527403B1 - Method of controlling fast forward and rewind modes on streaming VOD system - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

The present invention relates to a high speed playback mode control method in a video-on-demand system and a computer-readable recording medium having recorded thereon a program for realizing the method.

2. The technical problem to be solved by the invention

The present invention provides a method and a method for controlling a high speed mode in an on-demand video system, in which a media player requests key frames corresponding to a high speed playback mode to a video server, and accordingly receives and receives the corresponding key frames in parallel. Its purpose is to provide a computer readable recording medium having recorded thereon a program.

3. Summary of the Solution of the Invention

The present invention provides a method of controlling a high speed playback mode in an on-demand video system, comprising: a first step of requesting a multimedia content order; A second step of storing index information of the multimedia content transmitted from a video server; A third step of confirming that a high speed mode occurs while playing the multimedia content transmitted from the video server in a normal speed mode; A fourth step of selecting a plurality of key frames corresponding to the high speed mode by using the stored index information; Requesting the selected plurality of key frames; A sixth step of receiving in parallel a plurality of key frames transmitted in parallel from the video server; And a seventh step of playing the received plurality of key frames.

4. Important uses of the invention

The invention is used in video on demand systems and the like.

Description

{Method of controlling fast forward and rewind modes on streaming VOD system}

The present invention relates to a high speed mode control method and a computer readable recording medium recording a program for realizing the method in an on-demand video system, and more particularly, a media player may display key frames corresponding to the high speed playback mode. The present invention relates to a high speed mode control method and a computer readable recording medium having recorded thereon a program for realizing the method.

Recently, as the high-speed information communication network is popularized and the image related technology is developed, the application range of the multimedia contents is greatly expanded. In particular, there is a growing interest in Video On Demand (VOD), which provides customized video information according to the taste of subscribers at desired times and places through public network broadcasting, satellite network broadcasting, cable broadcasting, and internet broadcasting.

The video-on-demand service is a video on-demand (MOD), news on demand (NOD), a service that provides a video catalog of the product of the user's choice, providing a video of the newborn to a remote family, etc. It is used in a wide variety of fields such as services, video conferencing services, and distance education services.

On the other hand, such a video-on-demand service is to provide the video information to the user's media player as the media player (MultiMedia Player) of the user ordered the video information to the video server through the information communication network In addition, you can play, stop, pause, fast forward play, fast rewind play, and play the video at any position like a normal video equipment. All are provided.

1 is a configuration diagram of an embodiment of a communication network including a general media player and a video server.

As shown in FIG. 1, a communication network including a general media player and a video server includes a plurality of media players 100 installed on a client side computer or the like for playing back image data or audio data, and the media player 100. The video server 200 and the image data or audio for extracting the image data or the audio data stored in the multimedia database 300 and transmitting them to the media player 100 according to the image data request or the audio data request from the And a multimedia database 300 for storing data.

In the conventional method, the media player 100 will be described in detail with respect to a process of performing high-speed forward playback of an image requested by the video server 200 as follows.

2 is a diagram illustrating an embodiment of a high speed playback mode control process in a video system on demand.

First, the media player 100 requests a connection to the video server 200 (10), establishes a connection with the video server 200 after undergoing an authentication process such as checking a user ID and password (11). Then, the media player 100 requests the video data transmission to the video server 200 (12). Then, the video server 200 extracts the image data requested from the media player 100 in the multimedia database 300 (13), and sequentially transmits the frames of the extracted image data (14). Accordingly, the media player 100 reproduces the image data while sequentially receiving frames of the image data transmitted through a buffer (15). Then, when the high speed forward playback input signal (for example, the 2x forward playback button is pressed, etc.) is generated by the user or the like while the video data is being reproduced (16), the media player 100 is connected to the video server 200. In step 17, high speed forward reproduction is requested for the image data. Then, the video server 200 extracts key frames of image data corresponding to the corresponding high-speed forward requested from the media player 100 from the multimedia database 300 (18), and sequentially extracts the extracted key frames. Transmit (19). Accordingly, the media player 100 reproduces the key frames while sequentially receiving the transmitted key frames through a buffer (20). Here, as the media player 100 plays the key frames of the image data, the user can watch the image that is quickly played at a high speed (eg, 2 times speed).

Here, the video server 200 transmits image data, such as an MPEG bit stream format, to the media player 100. The image data includes a key frame, a delta frame, audio information, and the like.

The key frame is an independent frame having compressed information that can be decrypted individually, and the delta frame is a dependent frame generated with reference to the key frame and cannot be decrypted individually. As described above, the media player 100 decodes the first key frame (the first screen of the image) of the image data received from the video server 200, and then decodes the key frame transmitted thereafter and a delta frame corresponding thereto. Play it.

However, the conventional technology as described above is a video server 200-driven method, and the video server 200 plays the image data of the media player 100 every time in response to a high-speed forward playback request transmitted from the media player 100. Since the key frames to be transmitted to the media player 100 are extracted after checking, when the high-speed forward play request is received from the plurality of media players 100, the image data playback state of each media player 100 is checked and the corresponding key is received. Since it takes a long time to extract the frames, there is a problem in that a delay occurs in transmitting key frames to each media player 100, and thus the screen is cut off in the media player 100. In addition, the video server 200 is subjected to a significant system load in confirming the state of playback of each image data of the plurality of media players 100.

In addition, since the video server 200 sequentially transmits the image data (a plurality of frames) to the media player 100, the media player 100 transmits one image data. If the first frame and the next frame among the constituent frames do not continue to arrive in sequence, there is a problem that the screen is frequently cut off while playing the corresponding video data.

The present invention has been proposed in order to solve the above problems, the video on demand video player to request the key frame corresponding to the high-speed playback mode to the video server, and accordingly receive the corresponding key frames in parallel, and then play the video It is an object of the present invention to provide a high speed mode control method in a system and a computer-readable recording medium recording a program for realizing the method.

According to an aspect of the present invention, there is provided a method of controlling a high speed playback mode in an on-demand video system, comprising: a first step of requesting a multimedia content order; A second step of storing index information of the multimedia content transmitted from a video server; A third step of confirming that a high speed mode occurs while playing the multimedia content transmitted from the video server in a normal speed mode; A fourth step of selecting a plurality of key frames corresponding to the high speed mode by using the stored index information; Requesting the selected plurality of key frames; A sixth step of receiving in parallel a plurality of key frames transmitted in parallel from the video server; And a seventh step of playing the received plurality of key frames.

In addition, the method of the present invention, the eighth step of confirming that the normal speed mode occurs; A ninth step of selecting a plurality of frames corresponding to the normal speed mode by using the stored index information and requesting the video server; And a tenth step of receiving and playing back a plurality of frames transmitted in parallel from the video server.

In addition, the method of the present invention, the eleventh step of confirming that the normal double speed forward mode occurs in any position; A twelfth step of selecting a plurality of frames after the arbitrary position by using the stored index information and requesting the video server; And a thirteenth step of receiving and playing back a plurality of frames transmitted in parallel from the video server.

On the other hand, the present invention, the on-demand video system having a processor, a first function for requesting multimedia content order; A second function of storing index information of the multimedia content transmitted from a video server; A third function of confirming that a high speed mode occurs while playing the multimedia content transmitted from the video server in a normal speed mode; A fourth function of selecting a plurality of key frames corresponding to the high speed mode by using the stored index information; A fifth function of requesting the selected plurality of key frames; A sixth function of receiving a plurality of key frames in parallel transmitted from the video server; And a computer readable recording medium having recorded thereon a program for realizing a seventh function of reproducing the received plurality of key frames.

The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a diagram illustrating an embodiment of a high speed playback mode control process in an on-demand video system according to the present invention.

First, the media player 100 requests a connection to the video server 200 (50), establishes a connection with the video server 200 after undergoing an authentication process such as checking a user ID and password (51). Thereafter, the media player 100 requests the video data transmission to the video server 200 (52). Then, the video server 200 extracts the image data requested from the media player 100 from the multimedia database 300 (53) and transmits index information of the extracted image data (54). Accordingly, after storing the index information of the received image data (55), the media player 100 requests the video server 200 to transmit a plurality of frames according to the index information (56). Then, the video server 200 extracts the plurality of frames requested from the media player 100 from the multimedia database 300 (57), and then extracts the extracted plurality of frames to the media player 100. Transmit in parallel (58). Accordingly, the media player 100 reproduces the plurality of frames 59 while receiving the plurality of frames transmitted in parallel through a buffer. Thereafter, when the high speed forward playback input signal (for example, the 2x forward playback button is pressed or the like) is generated by the user or the like while the video data is being reproduced (60), the media player 100 is connected to the video server 200. Request a plurality of key frames corresponding to the corresponding high-speed forward (61). Then, the video server 200 extracts a plurality of key frames corresponding to the corresponding high-speed forward requested from the media player 100 from the multimedia database 300 (62), and then extracts the extracted plurality of key frames. Transmit in parallel (63). Accordingly, the media player 100 plays 64 the plurality of key frames while receiving the transmitted key frames in parallel through a buffer.

The media player 100 may be an application program installed in a computer or the like (e.g., Microsoft's Windows Media Player, Nullsoft's Winamp, Dionnet's SeeVideo Player, etc.) or a video playback device (e.g., Set-top Box (Set). Top Box, etc.).

4 is a flowchart illustrating a method of controlling a high speed mode in an on-demand video system according to the present invention.

First, the media player 100 connects to the video server 200 (400). At this time, the user inputs the Internet address of the video server 200 having the image to be watched on the Internet address window of the media player 100 or the like or connects to the video server 200 through a web browser. Then, the media player 100 is connected to the video server 200 after undergoing an authentication process such as checking a user ID and password from the video server 200. As another example, the video server 200 may verify the MAC address of the media player 100 and perform an authentication process.

Thereafter, the media player 100 requests the video data transmission to the video server 200 (401). At this time, the user checks a list of image data held by the video server 200 displayed through a pop-up window or a web browser of the media player 100, and then selects an image to be watched.

Thereafter, the media player 100 receives and stores index information of image data requested from the video server 200 (402). Here, the index information includes the Internet address of the image data, the compression codec used, the key frame position, the delta frame position, and the like.

Thereafter, the mode of the media player 100 is checked (403).

In the inspection result 403, the normal speed forward playback or the normal speed backward playback mode, a plurality of frames (key frame + delta frame +) corresponding to the initial position (that is, the beginning of the image data) according to the stored index information Audio) is requested (404). When the video data is reproduced for the first time, the normal double speed reverse playback mode is practically impossible. In addition, when a normal double speed backward playback input signal is generated from the user while the video data is being reproduced, a plurality of frames before the current position (ie, the playback portion of the current video data) according to the stored index information. Request key frame and delta frame except audio information.

Accordingly, the plurality of requested frames from the video server 200 are received in parallel through a buffer (405). At this time, the video server 200 extracts a plurality of frames requested from the media player 100 in the multimedia database 300 and then transmits them in parallel. Accordingly, the media player 100 temporarily stores the frames in the buffer after checking the playback order and size of the plurality of frames transmitted in parallel from the video server 200 by using the stored index information. Receive. Here, the video server 200 may reduce the load by directly extracting and transmitting the requested frames from the media player 100 without determining the playback order of the image data requested from the media player 100. have. In addition, the video server 200 transmits frames to the media player 100 in parallel using a transmission control protocol (TCP) scheme, thereby preventing data loss and delay.

Thereafter, the received plurality of frames is played (406). At this time, the media player 100 reproduces (decodes) frames temporarily stored in the buffer in order and displays them on a screen. In addition, the media player 100 refers to the compressed codec information included in the index information to play the frames through a codec stored in the client side.

As a result of the check 403, if a playback mode is started from an arbitrary position, a plurality of frames (key frame + delta frame + audio) corresponding to an arbitrary position according to the stored index information is requested (404). Accordingly, the processes '405' and '406' are performed. Here, the play mode from the arbitrary position refers to a mode in which the playback scroll bar of the media player 100 is changed to an arbitrary position by a user's mouse or the like and played from the changed position.

If the inspection result 403, the high speed forward playback mode or the high speed backward playback mode, a plurality of key frames corresponding to the corresponding high speed forward or high speed backward according to the stored index information is requested (408). At this time, after confirming that the high speed forward playback input signal or the high speed backward playback input signal is generated from the user, the media player 100 generates the key frames after the current playback portion of the image data when the high speed forward playback input signal is generated. If a high-speed reverse playback input signal is generated, key frames before the current playback portion of the video data are requested. In addition, the media player 100 does not select key frames according to the corresponding double speed (that is, in the 4x forward playback mode, the key frames after the current playback portion are selected at intervals of 4: 1). By using the index information, the distribution of key frames is checked to select key frames suitable for the corresponding double speed.

Accordingly, the requested plurality of key frames from the video server 200 are received in parallel through a buffer (409). At this time, the video server 200 extracts a plurality of key frames requested from the media player 100 in the multimedia database 300 and then transmits them in parallel.

Thereafter, the received plurality of key frames are played (410). At this time, the media player 100 reproduces key frames temporarily stored in the buffer in order and displays them on a screen. Accordingly, the user may watch the video played back quickly or backward according to the corresponding speed.

If the check result 403, the stop mode or the pause mode, the function is performed (411).

FIG. 5A is a diagram illustrating an embodiment of a buffer state of a media player in a normal double speed mode to which the present invention is applied, and FIG. 5B is a diagram illustrating an embodiment of a buffer state of a media player in a double speed or higher mode to which the present invention is applied. .

As shown in FIG. 5A, in the normal double speed mode to which the present invention is applied, the media player 100 buffers a plurality of frames (key frame, delta frame, audio information, etc.) transmitted in parallel from the video server 200. Save temporarily while receiving through. Then, the media player 100 plays back the corresponding frames stored in the order of the buffer.

In addition, the media player 100 checks the playback order and size of a plurality of frames transmitted in parallel from the video server 200 with reference to the index information received from the video server 200 and transmits the transmitted frames. Save to the location in the buffer.

As shown in FIG. 5B, in the double speed or higher mode to which the present invention is applied, the media player 100 temporarily stores a plurality of key frames transmitted in parallel from the video server 200 while receiving them through a buffer. The media player 100 then plays back the corresponding key frames stored in the order of the buffer. Accordingly, the user can watch the screen to be played according to the corresponding speed mode.

In addition, the media player 100 may perform a high speed playback mode such as 32x speed and 64x speed. That is, the media player 100 selects key frames according to the corresponding double speed by referring to the index information stored as the corresponding double speed mode input signal is generated, requests the video server 200, and accordingly, the video server 200. Plays key frames corresponding to the corresponding double speed transmitted from

As described above, the method of the present invention may be implemented as a program and stored in a recording medium (CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.) in a computer-readable form. Since this process can be easily implemented by those skilled in the art will not be described in more detail.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes are possible in the art without departing from the technical spirit of the present invention. It will be clear to those of ordinary knowledge.

According to the present invention, each media player requests key frames corresponding to the high speed playback mode to the video server using index information and plays the key frames transmitted accordingly. Since the video server does not need to check the playback status of each media player, etc. each time, the video server immediately sends the corresponding key frames to each media player, and the media player has an effect that a seamless screen can be played. have.

In addition, the present invention allows the media player to receive key frames transmitted in parallel from the video server in parallel, such that a plurality of key frames after the currently played key frame are immediately received and thus delayed in receiving the key frames. There is an effect that can prevent the screen from being frequently cut off while the image is being played at a high speed because it does not occur.

In addition, the present invention has the effect of reducing the system load of the video server according to the high-speed playback request from a plurality of clients by immediately transmitting the transmission request frame, without having to analyze the data requested from the client have.

1 is a block diagram of an embodiment of a communication network including a general media player and a video server.

2 is a diagram illustrating an embodiment of a high speed playback mode control process in an on-demand video system according to the related art.

3 is a diagram illustrating an embodiment of a high speed playback mode control process in an on-demand video system according to the present invention.

4 is a flowchart illustrating an embodiment of a high speed mode control method in an on-demand video system according to the present invention.

5A is a diagram illustrating an embodiment of a buffer state of a media player in a normal double speed mode to which the present invention is applied;

FIG. 5B is an exemplary diagram illustrating a buffer state of a media player in a double speed or higher mode to which the present invention is applied. FIG.

* Explanation of symbols on the main parts of the drawing

100: media player 200: video server

300: multimedia database

Claims (8)

In the high speed playback mode control method in the video system on demand, Requesting to order multimedia content; A second step of storing index information of the multimedia content transmitted from a video server; A third step of confirming that a high speed mode occurs while playing the multimedia content transmitted from the video server in a normal speed mode; A fourth step of selecting a plurality of key frames corresponding to the high speed mode by using the stored index information; Requesting the selected plurality of key frames; A sixth step of receiving in parallel a plurality of key frames transmitted in parallel from the video server; And Seventh step of playing the received plurality of key frames High speed playback mode control method on demand video system comprising a. The method of claim 1, The fourth step, If the high speed mode is the high speed forward playback mode, the plurality of key frames after the current playback position are selected using the stored index information. If the high speed mode is the high speed backward playback mode, the current playback is performed using the stored index information. A method of controlling a high speed playback mode in an on-demand video system, characterized in that it selects a plurality of key frames prior to the position. The method of claim 1, An eighth step of confirming that a normal speed mode occurs; A ninth step of selecting a plurality of frames corresponding to the normal speed mode by using the stored index information and requesting the video server; And A tenth step of receiving and playing back a plurality of frames transmitted in parallel from the video server High speed playback mode control method on demand video system further comprising a. The method of claim 3, wherein In the selecting of the plurality of frames corresponding to the normal speed mode using the stored index information in the ninth step, the stored index information is used when the normal speed mode is a normal forward playback mode. Selects a plurality of frames after the current playback position, and if the normal speed mode is the normal backward playback mode, selects frames other than audio information among the plurality of frames before the current playback position by using the stored index information. A high speed playback mode control method in an on-demand video system, characterized in that. The method according to claim 1 or 3, An eleventh step of confirming that a normal double speed forward mode occurs at an arbitrary position; A twelfth step of selecting a plurality of frames after the arbitrary position by using the stored index information and requesting the video server; And A thirteenth step of receiving and playing back a plurality of frames transmitted in parallel from the video server High speed playback mode control method on demand video system further comprising a. On-demand video system with a processor, A first function of requesting a multimedia content order; A second function of storing index information of the multimedia content transmitted from a video server; A third function of confirming that a high speed mode occurs while playing the multimedia content transmitted from the video server in a normal speed mode; A fourth function of selecting a plurality of key frames corresponding to the high speed mode by using the stored index information; A fifth function of requesting the selected plurality of key frames; A sixth function of receiving a plurality of key frames in parallel transmitted from the video server; And A seventh function of playing the received plurality of key frames A computer-readable recording medium having recorded thereon a program for realizing this. The method of claim 6, An eighth function of confirming that a normal speed mode occurs; A ninth function of selecting and requesting a plurality of frames corresponding to the normal double speed mode from the stored index information to the video server; And A tenth function of receiving and playing back a plurality of frames transmitted in parallel from the video server A computer-readable recording medium that records a program for further realization. The method according to claim 6 or 7, An eleventh function of confirming that a normal double speed forward mode occurs at an arbitrary position; A twelfth function of selecting a plurality of frames after the arbitrary position and requesting the video server by using the stored index information; And A thirteenth function for receiving and playing back a plurality of frames transmitted in parallel from the video server A computer-readable recording medium that records a program for further realization.