KR20090049672A - Mobile contents playing device with play point selection function by selecting script and method for the same - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital mobile content playback technology. Particularly, in a small portable digital mobile content playback device that is not equipped with high-end hardware and has a caption display function according to a video, the user can view the caption content at a specific point in time. When it is selected, the present invention relates to a mobile content playback technology for outputting a video and a subtitle on a screen by moving a video playback point to a corresponding point in time. According to the present invention, when a user selects a specific time point from the subtitles through a portable mobile content playback device that can simultaneously display a video and subtitles, the video playback is performed by moving the playback position of the video to the playback time point of the selected subtitle contents. When moving the MPEG encoded video to the subtitle playback time, the moving position of the video can be quickly moved with only a small amount of internal processing.

Mpeg, video, subtitle, mobile

Description

Mobile contents playing device with play point selection function by selecting script and method for the same}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital mobile content playback technology. Particularly, in a small portable digital mobile content playback device that is not equipped with high-end hardware and has a caption display function according to a video, the user can view the caption content at a specific point in time. When it is selected, the present invention relates to a mobile content playback technology for outputting a video and a subtitle on a screen by moving a video playback point to a corresponding point in time.

Currently, a technology for playing video content that is pre-stored or downloaded in a streaming manner through a digital device such as a personal computer is widely used. The video content is encoded by various compression codecs and decoded by a playback program and played back.

In addition, a technique for allowing a user to view the translated content through a readable scriptable subtitle in the case of video content that cannot be viewed in a native language by displaying the pre-written subtitle data together with the video data on the screen is already used.

Some playback programs use the technology to move the playback point of video content when a specific point of view is selected from the subtitle data, but this can be easily implemented in an environment equipped with high-end hardware such as a personal computer. In a portable mobile device having a battery capacity limitation condition, there are many technical limitations in applying the technology implemented in a general personal computer.

For example, video data encoded in MPEG format requires a lot of computational processing during the decoding process, and when a video is played back on a low-end personal computer, a problem occurs such that the screen is interrupted or the image and sound are out of sync.

In general, MPEG data played on portable mobile content uses simplified data by varying profile or level from MPEG data that can be played on a personal computer. In such an environment, the MPEG data is displayed and the video is displayed by subtitle selection. In order to move the playback time quickly and without delay, there is a need to apply a new type of technology.

An object of the present invention is a mobile content playback technology that can play the video from the playback point of the selected subtitle content and move the playback point without difficulty even with low hardware only when a specific point of time is selected through the portable small mobile content playback device that can be moved To provide.

In accordance with another aspect of the present invention, an apparatus for reproducing mobile content includes a memory configured to store MPEG video data and subtitle data in which sync information for MPEG video data is embedded; A decoder for decoding MPEG video data; A display unit for playing the decoded MPEG video data and synchronizing the caption data with the MPEG video data to be reproduced; In response to an external control signal, the entire contents of the caption data stored in the memory are displayed on the display unit. A playback position selection unit for searching for an I-picture at a close distance from the playback position in the MPEG video data and controlling the video to be played back from a frame generated by the I-picture; And a user interface configured to receive an external control signal.

According to an aspect of the present invention, there is provided a method of reproducing mobile content, the method including displaying the entire contents of caption data stored in a memory on a screen; Receiving an external control signal and setting a specific time point among caption data in response to the external control signal; Searching for a playback position corresponding to a specific time point in the MPEG video data stored in the memory; Searching for and selecting an I-picture of a near distance from the retrieved playback position; And playing the MPEG video data by setting the I-picture as the playback start position.

According to the present invention, when a user selects a specific time point from the subtitles through a portable mobile content playback device that can simultaneously display a video and subtitles, the video playback is performed by moving the playback position of the video to the playback time point of the selected subtitle contents. When moving the MPEG encoded video to the subtitle playback time, the moving position of the video can be quickly moved with only a small amount of internal processing.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 is a block diagram showing the overall configuration of a mobile content playback apparatus according to the present invention.

The mobile content playback apparatus 10 is a device that stores video content inside and can carry and watch video content while being portable and can output video content and subtitles simultaneously on the screen when subtitle data is added.

The mobile content playback apparatus 10 includes a memory 11, a decoder 12, a display unit 13, a playback position selection unit 14, and a user interface unit 15.

The memory video data is stored in the memory 11. In addition, the caption data may be stored. The caption data may include sync information for MPEG video data so that the caption data does not deviate from the video content.

The decoder 12 converts MPEG video data encoded in MPEG format into digital data that can be reproduced.

The display unit 13 reproduces the MPEG video data decoded by the decoder 12 through the screen, and simultaneously outputs the subtitle data stored in the memory 11 with the MPEG video data currently being reproduced. Then, the subtitles are displayed together with the subtitles on a part of the screen while the video screen is output.

When the playback position selection unit 14 receives an external control signal such as a user key input through the user interface unit 15, the display unit 13 displays the entire contents of the caption data stored in the memory 11 in response to the external control signal. On the screen. In this case, since the entire contents of the caption data cannot be displayed on one screen, the caption data in the caption data can be viewed by the user using a scroll method or a page turning method.

In addition, when the user looks at the caption contents in the caption data and selects specific contents from the caption data, the playback position selecting unit 14 selects a specific time point corresponding to the specific contents internally. For example, if a subtitle content displayed at 20 minutes elapses during the video running time is selected, a specific time point of 20 minutes elapsed time is selected.

The playback position selection unit 14 searches for the playback position corresponding to the specific viewpoint in the MPEG video data with respect to the selected specific viewpoint, and searches for an I-picture that is close to the playback position. Using the retrieved I-picture as a start point of playback, the MPEG video data is controlled to start playback from a frame generated by the corresponding I-picture.

The reason for selecting an I-picture as a playback point is that it is possible to recover an image frame on its own without using complicated computational processing to restore the image compared to a P-picture or a B-picture. This is because there are many advantages to implementing. This point will be described in more detail later with reference to FIGS. 2 and 3.

The user interface unit 15 receives an external control signal generated by a user's key input or an external manipulation of a user such as a stylus pen or a touch screen to perform a function such as playing a video and selecting a subtitle through a mobile content player. To make it possible.

2 is an exemplary diagram illustrating an embodiment of starting playback from an I-picture closest to a playback position when a user selects a subtitle in the present invention.

MPEG video data is composed of an I-picture constituting one frame, a P-picture restoring a frame with reference to the I-picture, and a B-picture restoring a frame with reference to the I-picture and P-picture. . The section from the I-picture to the next I-picture is called a GOP (Group of Picture). In this case, the I-picture is the most basic data for generating a frame, and one frame recovery is possible only by the I-picture itself.

Also, the MPEG video data used for DMB broadcasting does not include B-pictures requiring bidirectional reference because of the characteristics used to provide real-time broadcasting, and MPEG data is composed of only I-pictures and P-pictures.

That is, the MPEG video data may include all the I-pictures, the P-pictures, and the B-pictures, or may be composed of only the I-pictures and the P-pictures without the B-pictures generating frames by referring to both directions.

As shown, when the 'subtitle # 2' corresponding to a specific time point is selected by the user, the playback position on the video data corresponding to the 'subtitle # 2' is internally searched. In FIG. 2, the B-picture indicated by the arrow When the subtitle # 2 is displayed, it corresponds to the image being played back.

In this case, if the above process is performed in a personal computer sufficiently supported by hardware resources, it may be appropriate to select the previously selected B-picture as a playback time point. However, in order to reproduce B-pictures, frames need to be reproduced with reference to I-pictures and P-pictures, and thus, more complicated computational processing is required than I-pictures capable of reconstructing frames themselves.

However, the portable video content player has a limitation in processing a large amount of data compared to a personal computer, and also has a limitation in the amount of data required for rapid processing. In addition, since a portable battery is limited, an operation should be made to minimize power consumption.

Therefore, an I-picture at a close distance from the actual reproduction position is searched, and when there are a plurality of I-pictures, the I-picture at the closest distance is set to be played back. That is, in FIG. 2, the hatched I-picture immediately before the B-picture is selected, and when the user selects 'subtitle # 2', the video playback starts from a point slightly ahead of the actual playback position. Of course, since the subtitle data is also displayed in advance in time, the video and the subtitle are still kept in sync.

FIG. 3 is an exemplary view illustrating an embodiment of starting playback from an I-picture immediately preceding a time from a playback position when a user selects a caption. FIG.

Unlike the case of FIG. 2, the GOP of MPEG video data is composed of only an I-picture and a P-picture. As shown, when the user selects 'subtitle # 6', a P-picture in the middle of the GOP is selected as a time point corresponding to 'subtitle # 6'.

In this case, it can be seen that the I-picture in close proximity to the P-picture includes two I-pictures hatched. In the example of FIG. 3, the MPEG video data is set to be played back from the I-picture earlier in time.

4 is a flow chart showing the overall operation of the mobile content playback method according to the present invention.

First, the entire contents of the caption data stored in the memory are displayed on the screen (ST10). The process of displaying the entire contents of the caption data may occur by a user's key input during video playback, and the detailed operation process will be described with reference to FIG. 5.

Subsequently, an external control signal generated by a user's key operation or the like is input, and a specific point in time of the caption data is set in response to the input external control signal (ST20). That is, when the user selects the caption content of the video scene to be viewed from the entire contents of the caption data displayed through the step ST10, the playback time corresponding to the selected caption content is selected within the running time of the video.

Then, the playback position corresponding to the predetermined time point is searched for in the MPEG video data stored in the memory (ST30). For example, an I-picture is referred to in MPEG video data to find which P-picture generates an image of a corresponding time zone.

Next, an I-picture at a close distance from the retrieved playback position is searched for and selected (ST40). Then, the selected I-picture is set as the playback start point of the MPEG video content (ST50).

In other words, when a subtitle is selected through the portable video content player, the position where the subtitle is actually played may be slightly different. The reason for selecting the I-picture is that the image can be quickly and easily reconstructed as compared to the P-picture or the B-picture as described above with reference to FIGS. 1 and 2. The step ST40 in which the I-picture is selected will be described in detail later with reference to FIGS. 6 and 7.

Finally, MPEG video data is played by setting the selected I-picture as the playback start position (ST60).

FIG. 5 is a flowchart illustrating in detail the operation of the caption data full content display step ST10 of FIG. 4.

First, when the user presses the play button, the MPEG video content is decoded and played (ST11).

At this time, if the caption data is stored, the caption data is synchronized with the reproduced content together with the reproduced video content and displayed on the screen (ST12).

When an external control signal input occurs due to a user's key input (ST13), the entire contents of the currently displayed subtitle data are displayed on the screen. That is, the currently displayed subtitle data is written in the form of a text script, and the text is output in accordance with the video signal of the reproduced content. Therefore, in the subsequent process, the entire subtitle content to be displayed during the running time is displayed on the screen so that the user can select the desired subtitle text content while viewing the screen.

FIG. 6 is a flowchart illustrating an example of selecting an I-picture of the closest distance in the I-picture selection step ST40 of FIG. 4.

First, an I-picture within a predetermined distance from the searched playback position is searched (ST41). For example, a wider range of selectable I-pictures can be set for efficiency of hardware operation.

When there is more than one I-picture at a close distance from the searched reproduction position (ST42), the I-picture at the closest distance is selected (ST43).

However, if there is only one I-picture, no separate selection process is required and the searched I-picture is selected (ST44).

Then, the process proceeds to step ST50 of setting the selected I-picture as the playback start point.

FIG. 7 is a flowchart illustrating an example of selecting an I-picture that is advanced in time in the I-picture selection step ST40 of FIG. 4.

First, an I-picture within a predetermined distance from the searched playback position is searched (ST41-2). As mentioned in FIG. 6, a range of selectable I-pictures may be set wider for efficiency of hardware operation.

When there is more than one I-picture at a distance from the searched reproduction position (ST42-2), the I-picture that is advanced in time is selected (ST43-2). If there are three or more I-pictures within the search range, it may be set to select the most advanced I-picture.

However, if there is only one I-picture, no separate selection process is required and the searched I-picture is selected (ST44-2).

Then, the process proceeds to step ST50 of setting the selected I-picture as the playback start point.

Although the present invention has been described in more detail with reference to Examples, the present invention is not necessarily limited to these Examples, and various modifications can be made without departing from the spirit of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

1 is a block diagram showing the overall configuration of a mobile content playback apparatus according to the present invention;

2 is an exemplary diagram showing an embodiment of starting playback from an I-picture closest to a playback position when a user selects a subtitle in the present invention;

FIG. 3 is an exemplary view showing an embodiment of starting playback from an I-picture immediately preceding a time from a playback position when a user selects a subtitle in the present invention; FIG.

4 is a flow chart showing the overall operation of the mobile content playback method according to the present invention;

FIG. 5 is a flowchart illustrating in detail an operation of the caption data full content display step ST10 of FIG. 4;

FIG. 6 is a flowchart illustrating an embodiment of selecting an I-picture of the closest distance in the I-picture selection step ST40 of FIG. 4;

FIG. 7 is a flowchart illustrating an example of selecting an I-picture that is advanced in time in the I-picture selection step ST40 of FIG. 4.

Claims (7)

A memory for storing MPEG video data and subtitle data in which sync information of the MPEG video data is embedded; A decoder for decoding the MPEG video data; A display unit for playing the decoded MPEG video data and synchronizing the caption data with the reproduced MPEG video data and outputting the same; In response to an external control signal, the entire contents of the caption data stored in the memory are displayed on the display unit, and when a specific time point is selected from the caption data by an external control signal, playback corresponding to the specific time point in the MPEG video data is performed. A playback position selection unit for searching for a position and searching for an I-picture of a close distance from the playback position in the MPEG video data and controlling the video to be played back from a frame generated by the I-picture; And A user interface unit receiving the external control signal; Mobile content playback device configured to include. The method according to claim 1, The playback position selector controls the MPEG video data to be played from the closest I-picture starting point when there are a plurality of I-pictures in close proximity from the playback position corresponding to the specific time point. Mobile content playback device. The method according to claim 1, The playback position selection unit controls the MPEG video data to be played back from the start point of time when there are a plurality of I-pictures in close proximity from the playback position corresponding to the specific time point. . Displaying the entire contents of the caption data stored in the memory on the screen; Receiving an external control signal and setting a specific time point among the caption data in response to the external control signal; Searching for a playback position corresponding to the specific time point in MPEG video data stored in a memory; Searching for and selecting an I-picture of a near distance from the searched playback position; And Playing the MPEG video data by setting the I-picture as a playback start position; Mobile content playback method comprising a. The method according to claim 4, The displaying of the entire subtitle data content may include displaying on the screen MPEG video data and subtitle data synchronized to the MPEG video data; and when an external control signal is input during playback of MPEG video data, the entire subtitle data stored in the memory. Mobile content playback method further comprises the step of displaying the content on the screen. The method according to claim 4 or 5, The selecting of the I-picture may include selecting an I-picture that is closest to each other when there are a plurality of I-pictures that are close to each other from the playback position corresponding to the specific view point. How to play. The method according to claim 4 or 5, And selecting the I-picture in advance when there are a plurality of I-pictures in close proximity from the playback position corresponding to the specific time point.

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