U.S. patent number RE48,413 [Application Number 16/243,913] was granted by the patent office on 2021-01-26 for broadcast receiver and 3d subtitle data processing method thereof.
This patent grant is currently assigned to LG ELECTRONICS INC.. The grantee listed for this patent is LG Electronics Inc.. Invention is credited to Ho Taek Hong, Jin Pil Kim, Jong Yeul Suh.
United States Patent |
RE48,413 |
Suh , et al. |
January 26, 2021 |
Broadcast receiver and 3D subtitle data processing method
thereof
Abstract
A broadcast receiver and a 3D subtitle data processing method
thereof are disclosed. A method for processing three dimensional
(3D) subtitle data includes receiving, by a receiver, a broadcast
signal including 3D subtitle data, extracting, by an extracting
unit, subtitle display information for a base view and extended
subtitle display information for an extended view from the 3D
subtitle data, and controlling, by a controller, a 3D subtitle
display using the subtitle display information for the base view
and the extended subtitle display information for the extended
view.
Inventors: |
Suh; Jong Yeul (Seoul,
KR), Kim; Jin Pil (Seoul, KR), Hong; Ho
Taek (Seoul, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
LG Electronics Inc. |
Seoul |
N/A |
KR |
|
|
Assignee: |
LG ELECTRONICS INC. (Seoul,
KR)
|
Family
ID: |
42562142 |
Appl.
No.: |
16/243,913 |
Filed: |
January 9, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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13201320 |
Aug 12, 2014 |
8803948 |
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PCT/KR2009/007109 |
Dec 1, 2009 |
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61152234 |
Feb 12, 2009 |
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Reissue of: |
14319910 |
Jun 30, 2014 |
9544569 |
Jan 10, 2017 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04N
21/4884 (20130101); H04N 13/156 (20180501); H04N
13/183 (20180501); H04N 13/183 (20180501); H04N
21/42653 (20130101); H04N 21/4348 (20130101); H04N
13/194 (20180501); H04N 21/234327 (20130101); H04N
21/2362 (20130101); H04N 21/4314 (20130101); H04N
13/161 (20180501); H04N 21/4884 (20130101); H04N
21/816 (20130101); H04N 13/194 (20180501); H04N
21/4345 (20130101); H04N 21/8451 (20130101) |
Current International
Class: |
H04N
13/00 (20180101); H04N 21/2362 (20110101); H04N
21/431 (20110101); H04N 21/434 (20110101); H04N
21/488 (20110101); H04N 21/81 (20110101); H04N
13/161 (20180101); H04N 13/183 (20180101); H04N
13/156 (20180101); H04N 13/194 (20180101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1193439 |
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Sep 1998 |
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CN |
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1607750 |
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Apr 2005 |
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CN |
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10-2007-0058302 |
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Jun 2007 |
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KR |
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10-2008-0066437 |
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Jul 2008 |
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KR |
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2007064159 |
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Jun 2007 |
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WO |
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2008044191 |
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Apr 2008 |
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WO |
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2008115222 |
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Sep 2008 |
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WO |
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Other References
"Digital Video Broadcasting (DVB); Subtitling systems European
Broadcasting Union Union Europeenne de Radio-Television EBU-UER;
ETSI EN 300 743", IEEE, LIS, Sophia Antipolis Cedex, France, vol.
BC, No. V1.3.1, Nov. 1, 2006 (Nov. 1, 2006), XP014039581.
ISSN:0000-0001. cited by applicant.
|
Primary Examiner: LaRose; Colin M
Attorney, Agent or Firm: Dentons US LLP
Parent Case Text
This application is a .Iadd.reissue of U.S. patent application Ser.
No. 14/319,910, filed Jun. 30, 2014 (now U.S. Pat. No. 9,544,569),
which is a .Iaddend.continuation of U.S. application Ser. No.
13/201,320 filed on Aug. 12, 2011 which is a National Stage Entry
of International Application No. PCT/KR2009/007109, filed on Dec.
1, 2009, and claims the benefit of U.S. Provisional Application No.
61/152,234, filed Feb. 12, 2009, all of which are hereby
incorporated by reference for all purposes as if fully set forth
herein in their entireties.
Claims
The invention claimed is:
1. A method of processing a broadcast signal for a 3-dimensional
(3D) content, the method comprising: encoding video data for the 3D
content into a stream, the video data comprising a left picture for
a left view and a right picture for a right view for the 3D
content; generating signaling information for the video data,
wherein the signaling information includes subtitling descriptor
including subtitling type information, wherein the subtitling type
information indicates that type of subtitle is a 3D subtitle with
disparity information for the 3D content; generating packet data
including subtitle segment for subtitling of the 3D content; and
transmitting the broadcast signal including the video data, the
packet data and the signaling information, wherein the subtitle
segment includes a segment type information indicating type of data
in the subtitle segment, a page identifier indicating a page on
which the 3D subtitle is displayed, region information identifying
at least one region within the page, object part horizontal
position indicating a horizontal position of the top left pixel of
an object part in the at least one region, and the disparity
information indicating a difference between horizontal positions of
subtitles representing a same point in space in the right and left
view of the 3D content for the page, .[.and.]. wherein the subtitle
segment further includes region size information specifying a
horizontal width of the at least one region which is expressed in
pixels.Iadd., and wherein the subtitle segment further includes
region disparity information for indicating difference between
horizontal positions of regions identified by the region
information.Iaddend..
2. The method of claim 1, wherein the 3D subtitle includes at least
one of displayed image, text data, graphic data, and logo.
.[.3. The method of claim 1, wherein the subtitle segment further
includes region disparity information indicating difference between
horizontal positions of regions identified by the region
information..].
4. The method of claim 1, wherein the subtitle segment further
includes object part information identifying at least one object
part of the 3D subtitle within the at least one region and object
part disparity information indicates difference between horizontal
positions of object parts identified by the object part
information.
5. An apparatus for receiving a broadcast signal for a
3-dimensional (3D) content, the apparatus comprising: a receiving
unit that receives the broadcast signal including video data for
the 3D content, the video data comprising a left picture for a left
view and a right picture for a right view for the 3D content; an
extracting unit that extracts signaling information for the video
data and packet data including subtitle segment for subtitling of
the 3D content, wherein the signaling information includes
subtitling descriptor including subtitling type information, and
wherein the subtitling type information indicates that type of
subtitle is a 3D subtitle with disparity information for the 3D
content; and a controller that controls a display of the 3D
subtitle for the 3D content based on the subtitling type
information and the subtitle segment, wherein the subtitle segment
includes a segment type information indicating type of data in the
subtitle segment, a page identifier indicating a page on which the
3D subtitle is displayed, region information identifying at least
one region within the page, object part horizontal position
indicating a horizontal position of the top left pixel of an object
part in the at least one region, and the disparity information
indicating a difference between horizontal positions of subtitles
representing a same point in space in the right and left view of
the 3D content for the page, .[.and.]. wherein the subtitle segment
further includes region size information specifying a horizontal
width of the at least one region which is expressed in
pixels.Iadd., and wherein the subtitle segment further includes
region disparity information for indicating difference between
horizontal positions of regions identified by the region
information.Iaddend..
6. The apparatus of claim 5, wherein the 3D subtitle includes at
least one of displayed image, text data, graphic data, and
logo.
.[.7. The apparatus of claim 5, wherein the subtitle segment
further includes region disparity information indicating difference
between horizontal positions of regions identified by the region
information..].
8. The apparatus of claim 5, wherein the subtitle segment further
includes object part disparity information indicates difference
between horizontal positions of object parts identified by the
object part information.
.Iadd.9. A digital receiver for processing a stereoscopic content,
at least one subtitle and metadata, the digital receiver
comprising: a receiving unit configured to receive segments
including the stereoscopic content, the at least one subtitle and
the metadata, wherein the metadata is used for providing the at
least one subtitle, wherein the metadata comprises region ID for
providing an identifier of a display window, and flag information
for indicating whether region position information for the display
window is present or not, further the region position information
is used for representing a position of the display window on which
the at least one subtitle is to be rendered; and a controller
coupled with the receiving unit, the controller is configured to:
parse the metadata; and present the at least one subtitle together
with the stereoscopic content based on the metadata..Iaddend.
.Iadd.10. The digital receiver of claim 9, wherein the metadata
further comprises the region position information only when the
flag information has a specific value..Iaddend.
.Iadd.11. The digital receiver of claim 10, wherein the metadata
further comprises disparity information for representing a
disparity as a fraction of a width of the display window for at
least one view among the left and right views..Iaddend.
.Iadd.12. A method of transmitting a stereoscopic content, at least
one subtitle and metadata in a transmitter, the method comprising:
encoding bitstreams for the stereoscopic content, the stereoscopic
content comprising a left picture for a left view and a right
picture for a right view; generating the at least one subtitle and
the metadata, wherein the metadata is used for providing the at
least one subtitle, wherein the metadata comprises region ID for
providing an identifier of a display window, and flag information
for indicating whether region position information for the display
window is present or not, further the region position information
is used for representing a position of the display window on which
the at least one subtitle is to be rendered; and transmitting
segments including the stereoscopic content, the at least one
subtitle and the metadata..Iaddend.
.Iadd.13. The method of claim 12, wherein the metadata further
comprises the region position information only when the flag
information has a specific value..Iaddend.
.Iadd.14. The method of claim 13, wherein the metadata further
comprises disparity information for representing a disparity as a
fraction of a width of the display window for at least one view
among the left and right views..Iaddend.
.Iadd.15. A method of transmitting a stereoscopic content, at least
one subtitle and metadata in a transmitter, the method comprising:
encoding bitstreams for the stereoscopic content, the stereoscopic
content comprising a left picture for a left view and a right
picture for a right view; generating the at least one subtitle and
the metadata, wherein the metadata is used for providing the at
least one subtitle, wherein the metadata comprises region ID for
providing an identifier of a display window, and flag information
for indicating whether region position information for the display
window is present or not, wherein the metadata further comprises
the region position information when the flag information has a
specific value; and transmitting segments including the
stereoscopic content, the at least one subtitle and the
metadata..Iaddend.
.Iadd.16. The method of claim 15, wherein the specific value is
1..Iaddend.
Description
TECHNICAL FIELD
The present invention relates to a broadcast receiver and a three
dimensional (3D) subtitle data processing method thereof, and more
particularly to a broadcast receiver for receiving 3D subtitle data
and processing the received 3D subtitle data in consideration of
either a display condition of a 3D video display device or an
effect intended by transmission of subtitle data, and a method for
processing the 3D subtitle data.
BACKGROUND ART
Generally, a three dimensional (3D) image (or a stereoscopic image)
provides a user's eyes with a stereoscopic effect using the
stereoscopic visual principle. A human being feels both near and
far through a binocular parallax caused by a distance between their
eyes spaced apart from each other by about 65 mm, such that the 3D
image enables both right and left eyes to respectively view
associated planar images, resulting in the stereoscopic effect and
the perspective effect.
The above-mentioned 3D image display method may be classified into
a stereoscopic scheme, a volumetric scheme, a holographic scheme,
etc. In case of using the stereoscopic scheme, the 3D image display
method provides a left view image to be viewed by the left eye and
a right view image to be viewed by the right eye, such that the
user's left eye views the left view image and the user's right eye
views the right view image through either polarization glasses or a
display device, resulting in recognition of the 3D image
effect.
DISCLOSURE OF INVENTION
Technical Problem
Accordingly, the present invention is directed to a broadcast
receiver and a 3D subtitle data processing method thereof that
substantially obviate one or more problems due to limitations and
disadvantages of the related art.
An object of the present invention is to provide a broadcast
receiver for receiving 3D subtitle data under a 3D broadcast
environment, processing the received 3D subtitle data in
consideration of a display condition of a 3D video display device
and a 3D effect intended by a content manufacturer, displaying the
processed 3D subtitle data, and thus providing a user with more
effective and convenient broadcast environments, and 3D subtitle
data processing method for use in the broadcast receiver.
Solution to Problem
The object of the present invention can be achieved by providing a
method for processing three dimensional (3D) subtitle data, the
method including receiving, by a receiver, a broadcast signal
including 3D subtitle data, extracting, byan extracting unit,
subtitle display information for a base view and extended subtitle
display information for an extended view from the 3D subtitle data,
and controlling, by a controller, a 3D subtitle display using the
subtitle display information for the base view and the extended
subtitle display information for the extended view.
In another aspect of the present invention, provided herein is a
broadcast receiver including a receiver for receiving a broadcast
signal including 3D subtitle data, an extracting unit for
extracting subtitle display information for a base view and
extended subtitle display information for an extended view from the
3D subtitle data, and a controller for controlling a 3D subtitle
display using the subtitle display information for the base view
and the extended subtitle display information for the extended
view.
Advantageous Effects of Invention
According to embodiments of the present invention, the broadcast
receiver can process subtitle data according to a 3D effect of
received 3D subtitle data, and display the processed subtitle
data.
In addition, according to embodiments of the present invention, a
3D subtitle data processing method maintains compatibility with a
2D legacy broadcast receiver, and at the same time displays
subtitle data having a 3D effect through a broadcast receiver
capable of displaying 3D video data.
BRIEF DESCRIPTION OF DRAWINGS
The accompanying drawings, which are included to provide a further
understanding of the invention, illustrate embodiments of the
invention and together with the description serve to explain the
principle of the invention.
In the drawings:
FIG. 1 shows a syntax structure of an extended Display Definition
Segment (DDS) acting as extended subtitle display information
according to one embodiment of the present invention.
FIG. 2 shows a syntax structure of an extended Page Composition
Segment (PCS) acting as extended subtitle display information
according to one embodiment of the present invention.
FIG. 3 shows a syntax structure of an extended Region Composition
Segment (RCS) acting as extended subtitle display information.
FIG. 4 shows a syntax structure of an extended Object Data Segment
(ODS) acting as extended subtitle display information according to
one embodiment of the present invention.
FIG. 5 is a flowchart illustrating a method for receiving and
processing 3D subtitle data according to one embodiment of the
present invention.
FIG. 6 is a block diagram illustrating a broadcast receiver for
receiving and processing 3D subtitle data according to one
embodiment of the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
Reference will now be made in detail to the preferred embodiments
of the present invention, examples of which are illustrated in the
accompanying drawings. The detailed description, which will be
given below with reference to the accompanying drawings, is
intended to explain exemplary embodiments of the present invention,
rather than to show the only embodiments that can be implemented
according to the present invention.
Prior to describing the present invention, it should be noted that
most terms disclosed in the present invention are defined in
consideration of functions of the present invention and correspond
to general terms well known in the art, and can be differently
determined according to intention of those skilled in the art,
usual practices, or introduction of new technologies. In some
cases, a few terms have been selected by the applicant as necessary
and will hereinafter be disclosed in the following description of
the present invention. Therefore, it is preferable that the terms
defined by the applicant be understood on the basis of their
meanings in the present invention.
The 3D image display method includes a stereoscopic imaging scheme
in which two view points are considered and a multi-view imaging
scheme in which three or more view points are considered. In
contrast, a single view image scheme shown in the related art may
also be referred to as a monoscopic image scheme.
The stereoscopic imaging scheme is designed to use one pair of
right and left view images acquired when a left-side camera and a
right-side camera spaced apart from each other by a predetermined
distance capture the same target object. The multi-view imaging
scheme uses three or more images captured by three or more cameras
spaced apart by a predetermined distance or angle. Although the
following description discloses embodiments of the present
invention using the stereoscopic imaging scheme as an example, the
inventive concept of the present invention may also be applied to
the multi-view imaging scheme.
A stereoscopic image or multi-view image may be compressed and
coded according to a variety of methods including a Moving Picture
Experts Group (MPEG) scheme, and transmitted to a destination.
For example, a stereoscopic image or a multi-view image may be
compressed and coded according to the H.264/Advanced Video Coding
(AVC) scheme, and transmitted. In this case, the reception system
may decode a received image in reverse order of the H.264/AVC
coding scheme, such that it is able to obtain the 3D image.
In addition, one of a left view image and a right view image of a
stereoscopic image or one of multiple-view images may be assigned
to an image of a base layer, and the remaining one may be assigned
to an image of an extended layer. The base layer image may be
encoded using the same method as the monoscopic imaging method. In
association with the extended layer image, only information of the
relationship between the base layer image and the extended layer
image may be encoded and transmitted. As an exemplary compression
coding scheme for the base layer image, a JPEG, an MPEG-2, an
MPEG-4, or a H.264/AVC scheme may be used. For convenience of
description, the H.264/AVC scheme may be exemplarily used in one
embodiment of the present invention. In one embodiment of the
present invention, the compression coding scheme for an image of an
upper or higher layer may be set to the H.264/Multi-view Video
Coding (MVC) scheme.
When the MVC scheme is additionally applied to the AVC scheme or
the right/left image sequences are coded using only the AVC scheme
so as to implement the stereoscopic display, one point to be duly
considered when broadcasting corresponding 3D content data is
compatibility with the 2D broadcast receiver of the related art.
For the related broadcast receiver incapable of supporting the 3D
image display, if one of right and left view images is encoded and
transmitted according to a backward compatible method, the 2D
broadcast receiver recognizes and outputs only the corresponding
signal, such that it may be possible for a user to view the
corresponding content data through the related device. In the
following description, a base layer image of a time point where
content data is transferred for a legacy broadcast receiver may be
referred to as base view video data (or a base video), and an
extended layer image transferred for displaying a 3D image may be
referred to as extended view video data (or an extended video).
In the case of transferring the base view video data and the
extended view video data as described above, a legacy 2D broadcast
receiver receives the base video data so that it can display a 2D
image, and a 3D broadcast receiver receives base view video data
and extended view video data so that it can display a 3D image.
However, unexpected problems may occur in a method for displaying
subtitle data.
A Digital Video Broadcasting (DVB) system will hereinafter be used
as an example of a system for transmitting, receiving, and
processing subtitle data.
The term `Subtitle` in the following description may include not
only a subtitle but also displayed image, text data, graphic image,
logo, etc which are additionally displayed to basic video data.
The DVB broadcast system transmits subtitle data as a variety of
information of a subtitle. At this time, the subtitle data may
include not only subtitle display information including
configuration, size, position, etc. needed for displaying a
subtitle, but also information of a display color of a subtitle.
The subtitle display information includes display definition
information associated with a display window structure needed for
displaying a subtitle, page composition information, region
composition information, object data information, and the like.
From the viewpoint of a syntax structure for data transmission,
display definition information may be referred to as a display
definition segment, page composition information may be referred to
as a page composition segment, region composition information may
be referred to as a region composition segment, and object data
information may be referred to as an object data segment.
A related DVB broadcast signal provides only basic subtitle display
information. Accordingly, when a 3D broadcast receiver desires to
display the basic subtitle display information, the basic subtitle
display information may be represented by a 2D broadcast signal or
may not be displayed. Therefore, it is necessary to transmit
information capable of allowing even the subtitle display
information to be displayed in a 3D format, and a broadcast
receiver capable of displaying subtitle data in a 3D format using
the above-mentioned information and a data processing method
thereof are needed.
In the case of displaying a stereoscopic image, left view video
data and right view video data are horizontally shifted by a
predetermined distance so as to implement a 3D effect, and then
displayed. At this time, a variety of representation values (such
as a shifted distance) capable of indicating the 3D effect may be
used. In accordance with the embodiment of the present invention, a
disparity value will hereinafter be used as such a representation
value of the 3D effect.
The 3D effect may be acquired from the process in visual perception
leading to the sensation of depth from two slightly different
projections of the world onto the retinas of the eyes. The
difference in the two retinal images may be called horizontal
disparity, retinal disparity, or binocular disparity. Hereinafter,
for convenience of description and better understanding of the
present invention, the difference between the two retinal images
will only be referred to as `disparity`.
For example, in the case of transmitting 3D video data, respective
scenes of the 3D video data may have different 3D effects. In this
case, disparity values for corresponding scenes are transmitted to
a broadcast receiver, so that the broadcast receiver controls and
displays the 3D effect using the disparity values. Although other
representation values (for example, a depth value, a pixel
interval, a screen size, etc.) instead of the above disparity
values may be used to display the 3D effect, it should be noted
that the embodiments of the present invention will exemplarily use
the disparity value for convenience of description and better
understanding of the present invention.
In the case of transmitting subtitle data using the related DVB
transmission scheme, the 3D broadcast receiver receives base view
video data and extended view video data and displays the received
base view video data and the received extended view video data as
3D video data. However, the subtitle data has no information for a
3D display, such that it has a disadvantage in that it must display
3D video data as a 2D format. In this case, the subtitle can be
displayed only as base view video data or an extended view video
data, and a user views the subtitle in a 2D format in a different
way from a 3D image, so that the user may experience dizziness and
feel fatigue of eyes.
Accordingly, it is necessary to transmit both 3D video data and
information of a 3D effect to the related subtitle data. In this
way, the 3D effect information may be inserted into the related
subtitle display information or it is possible to transmit
additional subtitle display information.
In accordance with a method for transmitting additional subtitle
data, the stereoscopic image requires two viewpoint video data
(i.e., left view video data and right view video data) to display
the 3D effect, so that related subtitle display information may be
used as subtitle display information of one viewpoint, and subtitle
display information of another viewpoint may be additionally
transmitted. For example, the related subtitle display information
may be set to a subtitle for displaying data at a base view, and
subtitle display information of a subtitle to be displayed at an
extended view may be additionally transmitted. In accordance with
the above-mentioned method, when two subtitle display information
is transmitted and at the same time 3D effect information is
inserted into one or two subtitle display information and the
inserted result is transmitted, a 3D receiver can display subtitle
data having the 3D effect in the same manner as in a method for
displaying stereoscopic video data.
A method for transmitting the additional subtitle display
information may be advantageous to a method in which related
subtitle display information is modified and transmitted. In other
words, the related 2D broadcast receiver is designed to process and
display only related subtitle display information without
processing additional subtitle display information undefined in the
related subtitle display information, such that the above method
for transmitting additional subtitle display information can be
easily compatible with the related 2D receiver.
Therefore, the following embodiment of the present invention will
disclose a method for transmitting subtitle data by constructing
not only related subtitle display information but also other
subtitle display information for a 3D display. The above-mentioned
additional subtitle display information may also be referred to as
extended subtitle display information.
FIG. 1 shows a syntax structure of an extended Display Definition
Segment (DDS) acting as extended subtitle display information
according to one embodiment of the present invention.
The DDS includes display width information and display height
information of a TV image in which a DVB subtitle is rendered. In
other words, the DDS indicates a display size of a video image
including a subtitle stream to be displayed. In one embodiment of
the present invention, an extended DDS (DDS_EXT) shown in FIG. 1 is
transmitted, so that a receiver can control an output of a subtitle
at an extended view.
Individual fields of the extended DDS shown in FIG. 1 are as
follows.
A `dds_version_number` field may indicate aversion of the extended
DDS.
A `display_window_flag` field may indicate whether a subtitle
display set associated with the extended DDS is intended to be
rendered in a window within the display size defined by
`display_width` and `display_height` fields or to be rendered
directly within the display size defined by `display_width` and
`display_height` fields.
A `display_width` field may indicate a maximum horizontal width in
pixels of a display assumed by a subtitling stream associated with
the extended DDS.
A `display_height` field may indicate a maximum vertical height in
lines of a display in lines of a display assumed by a subtitling
stream associated with the extended DDS.
A `display_window_horizontal_position_minimum` field may indicate a
left-hand most pixel of a subtitle display set with reference to a
left-hand most pixel of a display.
A `display_window_horizontal_position_maximum` field may indicate a
right-hand most pixel of a subtitle display set with reference to a
left-hand most pixel of a display.
A `display_window_vertical_position_minimum` field may indicate an
upper most line of a subtitle display set with reference to a top
line of a display.
A `display_window_vertical_position_maximum` field may indicate a
bottom line of a subtitle display set with reference to a top line
of a display.
The above-mentioned fields may be pre-contained in the DDS, and
then be transmitted. In this case, information of the same or
duplicated fields having been transmitted in the DDS is omitted and
as such only the following information may be transmitted.
A `page_id` field 1020 may indicate an identifier (ID) of a page on
which a subtitle is displayed. In case of a `page_id` value, the
subtitle will be displayed on the same page at a base view and an
extended view, so that the `page_id` value may be identical to a
`page_id` value of a DDS corresponding to the base view, and then
be transmitted.
A `segment_type` field 1010 may have a value different from a
related DDS value (e.g., 0x14), and must have a specific value
(e.g., 0x44) capable of identifying an extended DDS.
A `target_view_position` field 1030 may indicate a view position to
which the extended DDS is applied. In other words, the
`target_view_position` field 1030 indicates viewpoint information
for displaying a stereoscopic subtitle. For example, if the
subtitle display of a corresponding extended DDS is applied to a
left image, the `target_view_position` field 1030 may be set to a
value of `0`. If the subtitle display of a corresponding extended
DDS is applied to a right image, the `target_view_position` field
1030 may be set to a value of `1`.
A `minimum_disparity_value` field 1040 may indicate a minimum value
of a disparity capable of being represented by a left image and a
right image. The lower the disparity value of the
`minimum_disparity_value` field 1040 (i.e., the closer the
disparity value of the `minimum_disparity_value` field 1040 is to a
negative value), the image forming position gradually moves to the
front of the screen.
A `maximum_disparity_value` field 1050 may indicate a maximum value
of a disparity value capable of being represented by a left image
and a right image. The higher the disparity value of the
`maximum_disparity_value` field 1050 (i.e., the closer the
disparity value of the `maximum_disparity_value` field 1050 is to a
positive value), the image forming position gradually moves to the
interior of the screen.
The extended DDS may define the range of a disparity value capable
of being allocated when a subtitle is displayed through the
`minimum_disparity_value` field 1040 and the
`maximum_disparity_value` field 1050.
As described above, in association with the DDS, the extended DDS
includes not only viewpoint allocation information for individual
subtitles, but also 3D effect information (i.e., disparity values),
such that a receiver can display a subtitle having the 3D
effect.
FIG. 2 shows a syntax structure of an extended Page Composition
Segment (PCS) acting as extended subtitle display information
according to one embodiment of the present invention.
Referring to FIG. 2, the PCS includes information of constituent
components of a displayed subtitle. The PCS may include usage- and
positioning-information of at least one region constructing the
displayed page. In accordance with one embodiment of the present
invention, the extended PCS (PCS_EXT) shown in FIG. 2 is
transmitted, such that the receiver can control an output of a
subtitle at an extended view.
Individual fields of the extended PCS shown in FIG. 2 are as
follows.
A `page_id` field may indicate an identifier (ID) of a page on
which a subtitle is displayed. In case of a `page_id` value, the
subtitle will be displayed on the same page at a base view and an
extended view, so that the `page_id` value may be identical to a
`page_id` value of a DDS corresponding to the base view, and then
be transmitted.
A `page_time_out` field may indicate a period, expressed in
seconds, after which a page instance is no longer valid and
consequently shall be erased from the screen, should it not have
been redefined before that.
A `page_version_number` field may indicate a version of the
extended PCS.
A `page_state` field may indicate a status of a subtitling page
instance described in the extended PCS.
A `region_id` field may indicate a unique identification of a
region within a page. The `region_id` field may display a subtitle
in the same region at the base view and the extended view, such
that it is identical to a `region_id` value of a PCS corresponding
to the base view and then transmitted.
A `region_horizontal_address` field indicates a horizontal address
of a top left pixel of this region. The left-most pixel of the
active pixels has a horizontal address of zero, and the pixel
address increases from left to right.
A `region_vertical_address` field may indicate a vertical address
of a top line of this region. The top line of the frame is a line
of zero, and the line address increases by one within the frame
from top to bottom.
A `target_view_position` field 2010 may indicate a view position at
which the extended PCS is applied. That is, the
`target_view_position` field 2010 may indicate viewpoint
information for displaying a stereoscopic subtitle. For example, if
a subtitle display of a corresponding extended PCS is applied to a
left image, the `target_view_position` field 2010 may be set to a
value of `0`. If a subtitle display of a corresponding extended PCS
is applied to a right image, the `target_view_position` field 2010
may be set to a value of `1`.
A `region_disparity_value` field 2020 may indicate a disparity
between a first region applied to the left image and a second
region applied to the right image. The `region_disparity_value`
field 2020 may indicate a horizontal displacement of other view on
the basis of a target view. In the case of transmitting a value of
`region_disparity_value` field 2020, a `region_horizontal_address`
field and a `region_vertical_address` field may be redundant, so
that the redundant fields may be omitted as necessary.
For example, it is assumed that the `target_view_position` field of
the extended PCS has a value of 1, the `region_disparity_value`
field has a value of 20, and the `region_horizontal_address` field
has a value of N. In this case, a subtitle for the extended PCS is
displayed as a right image, and a subtitle for the PCS is displayed
as a left image. In this case, the horizontal position of the
subtitle displayed on the left image is `N`, the horizontal
position of the subtitle displayed on the right image is `N-20`, so
that a binocular parallax is generated in response to a difference
in horizontal positions between the left image and the right image,
resulting in the occurrence of a 3D effect.
FIG. 3 shows a syntax structure of an extended Region Composition
Segment (RCS) acting as extended subtitle display information.
The RCS includes a list of displayed objects and position
information of the objects. In accordance with one embodiment of
the present invention, the extended RCS (RCS_EXT) shown in FIG. 3
is transmitted, so that the receiver can control an output of a
subtitle at the extended view.
Individual fields of the extended RCS shown in FIG. 3 are as
follows.
A `region_id field` may identify a region for which information is
contained in this RCS_EXT.
A `region_version_number` field may indicate a version of this
region.
If a `region_fill_flag` field is set to a value of `1`, the
`region_fill_flag` field means signals indicating that the region
is to be filled with the background color defined in the
`region_n-bit_pixel_code` fields in this segment.
A `region_width` field may specify a horizontal length of this
region, and is expressed in number of pixels.
A `region_height` field may specify a vertical length of the
region, and is expressed in number of pixels.
A `region_level_of_compatability` field may indicate a minimum type
of Color Look Up Table (CLUT) that is necessary in the decoder to
decode this region.
A `region_depth` field may identify an intended pixel depth for
this region.
A `CLUT_id` field may identify a family of CLUTs applied to this
region.
A `region_n(8, 4 and 2)-bit_pixel_code` field may specify the entry
of the applied n-bit CLUT as background color for the region when
the `region_fill_flag` field is set.
A `processed_length` field is the number of bytes from the field(s)
within a while-loop that has been processed by the decoder.
An `object_id` field may identify an object shown in the
region.
An `object_type` field may identify a type of object.
An `object_provider_flag` field may indicate how this object is
provided.
An `object_horizontal_position` field may specify a horizontal
position of the top left pixel of this object, and is expressed in
number of horizontal pixels, relative to a left hand edge of the
associated region.
An `object_vertical_position` field may specify a vertical position
of the top left pixel of this object, and is expressed in number of
lines, relative to the top of the associated region.
A `foreground_pixel_code` field may specify the entry in the
applied CLUT that has been selected as the foreground color of the
character(s).
A `background_pixel_code` field may specify the entry in the
applied CLUT that has been selected as the background color of the
character(s).
A `target_view_position` field 3010 may indicate a view position at
which the extended RCS is applied. That is, the
target_view_position' field 3010 may indicate viewpoint information
for displaying a stereoscopic subtitle. For example, if the
subtitle display of a corresponding extended RCS is applied to a
left image, the `target_view_position` field 3010 may be set to a
value of `0`. If a subtitle display of a corresponding extended RCS
is applied to a right image, the `target_view_position` field 3010
may be set to a value of `1`.
An `object_disparity_value` field 3020 may indicate a disparity
between a first object applied to a left image and a second object
applied to a right image. A value of the `object_disparity_value`
field 3020 may indicate a horizontal displacement of other view on
the basis of a target view.
FIG. 4 shows a syntax structure of an extended Object Data Segment
(ODS) acting as extended subtitle display information according to
one embodiment of the present invention.
The ODS may include data of a plurality of displayed objects. In
one embodiment of the present invention, an extended ODS (ODS_EXT)
shown in FIG. 4 is transmitted, so that a receiver can control an
output of a subtitle at an extended view.
In case of the ODS, if a disparity field is added in units of each
object contained in the region of the extended RCS, a disparity can
be adjusted in units of each object using the disparity field, so
that different 3D effects can be assigned to each objects contained
in the region. Therefore, the ODS for a base view can be applied
even to a process for displaying a subtitle at an extended view
without any change. At this time, an identifier (ID) identical to
that of the ODS used in the base view may be established in the
extended RCS, and then transmitted. Alternatively, the broadcast
receiver may copy or read a received ODS, such that it may control
a subtitle display for the extended view. However, different
objects may be used at respective viewpoints. At this time, the
extended ODS may transmit data of an additional object. In the
embodiment of the present invention, the ODS used for displaying a
subtitle for the extended view may be referred to as an extended
ODS. In this case, the term `extended ODS` may include the
above-mentioned examples in the following description.
Individual fields of the extended ODS are as follows.
An `object_id` field may identify within the page an object for
which data is contained in this `ODS_EXT` field.
An `object_version_number` may indicate a version of this segment
data.
An `object_coding_method` may specify a method used for coding the
object.
When a `non_modifying_colour_flag` field is set to a value of 1,
this `non_modifying_colour_flag` field indicates that the CLUT
entry value `1` is a non-modifying color.
A `top_field_data_block_length` field may specify the number of
bytes contained in the `pixel-data_sub-blocks` field for the top
field.
A `bottom_field_data_block_length` field may specify the number of
bytes contained in the `data_sub-block` field for the bottom
field.
A `processed_length` field may indicate the number of bytes from
the field(s) within a while-loop that has been processed by the
decoder.
An `stuff_bits` field may indicate eight stuffing bits that shall
be coded as `0000 0000`.
A `number_of_codes` field may specify the number of character codes
in the string.
A `character_code` field may specify a character through its index
number in the character table identified in the
`subtitle_descriptor` field.
Configuration of subtitle display information for displaying a
stereoscopic subtitle in accordance with one embodiment of the
present invention and a method for processing the subtitle display
information will hereinafter be described.
The configuration and process of a Display Definition Segment (DDS)
and a Page Composition Segment (PCS) for displaying a stereoscopic
subtitle according to one embodiment of the present invention will
hereinafter be described.
In order to allow a receiver to display a stereoscopic subtitle,
the receiver must receive subtitle information of two views, i.e.,
one subtitle information for a base view and the other subtitle
information for an extended view. A transmission system can
transmit a DDS and a PCS for the base view and the extended DDS and
the extended PCS for the extended view.
In this case, in the case where a value incapable of being
recognized by a related 2D broadcast receiver is established in a
segment type of each of the extended DDS and the extended PCS, and
is then transmitted, the related 2D broadcast receiver discards the
extended DDS and the extended PCS, and controls a subtitle display
using the DDS and the PCS. The 3D broadcast receiver controls a
subtitle display for the base view using the DDS and the PCS, and
controls a subtitle display for the extended view using the
extended DDS and the extended PCS, so that it can display a
subtitle having the 3D effect.
Next, the configuration and process of a Region Composition Segment
(RCS) for displaying a stereoscopic display according to another
embodiment of the present invention will hereinafter be
described.
The RCS may include information about a list of displayed objects
and information about positions of the objects in the region. In
the case of transmitting the extended PCS, a segment type value
incapable of being analyzed by the related 2D broadcast receiver
may be established in the extended RCS corresponding to a region
identifier (ID) contained in the extended PCS so as to prevent
operations of the related 2D broadcast receiver from being
affected, and the established segment type value is then
transmitted. In the case of transmitting the extended RCS in
accordance with one embodiment of the present invention, the
segment type value may be set to `0x41`. In this case, the extended
RCS may have the same structure as in the related RCS. In this
embodiment of the present invention, the extended RCS may
correspond to a structure acquired when the `target_view_position`
field 3010 and the `object_disparity_value` field 3020 are deleted
from the table structure shown in FIG. 3.
In addition, region composition information for the extended view
may be transmitted using the RCS (i.e., segment type=0x11) instead
of using the extended RCS. In this case, the region ID of this RCS
is unavailable in the received PCS, so that the related 2D
broadcast receiver can discard the above RCS.
The configuration and process of an Object Data Segment (ODS) for
displaying a stereoscopic subtitle according to another embodiment
of the present invention will hereinafter be described in
detail.
The RCS or the extended RCS includes object information for
constructing the region, and detailed information of a
corresponding object may be contained in the ODS and then be
transmitted. In this case, in order to prevent operations of the
related 2D broadcast receiver from being affected, the extended ODS
for describing a subtitle object for the extended view may be
transmitted. The extended ODS has the same structure as in the
related ODS, and may be assigned another segment type value (e.g.,
0x43) different from that of the related ODS and then be
transmitted.
In addition, object information for the extended view may be
transmitted using the related ODS instead of using the extended
ODS. In this case, the object ID of the received ODS is
unavailable, so that the related 2D broadcast receiver can discard
the above ODS.
In accordance with one embodiment of the present invention, a
variety of combinations may be constructed according to
configurations of the above-mentioned `DDS_EXT`, `PCS_EXT`
`RCS_EXT` (or `RCS`), and `ODS_EXT` (or `ODS`) and methods for
transmitting these segments. That is, the `DDS_EXT`, `PCS_EXT`,
`RCS_EXT`, and `ODS_EXT` are not constructed to have the same 3D
effect, and are constructed to have different 3D effects. For
example, different disparity values may be assigned to the
`DDS_EXT`, `PCS_EXT`, `RCS_EXT`, and `ODS_EXT`. As a result, a
variety of 3D subtitle combinations which have different 3D effects
according to pages, regions, and objects of individual subtitles
can be displayed.
FIG. 5 is a flowchart illustrating a method for receiving and
processing 3D subtitle data according to one embodiment of the
present invention.
Referring to FIG. 5, the broadcast receiver receives a DVB
broadcast stream, and extracts subtitle data from the received
broadcast stream at step S5010. In more detail, the broadcast
receiver parses a Program Map Table (PMT) from the DVB broadcast
stream, obtains a PID value of a stream having a stream type
(stream type=0x06), and receives a Packet Elementary Stream (PES)
corresponding to a DVB subtitle. In this case, the broadcast
receiver can obtain basic information of a subtitle from the PMT.
In accordance with one embodiment of the present invention, the
broadcast receiver determines whether current data is a 3D subtitle
by referring to a `subtitling type` field of a
`subtitling_descriptor` field contained in the PMT, so that it can
inform a user of information about the availability or
non-availability of a 3D subtitle. The broadcast receiver reads a
PES packet, which has a value `0x20` of a `data_identifier` field
and a value `0x00` of a `subtitle stream id` value, so that it can
extract subtitle data using the read PES packet.
The broadcast receiver performs section-filtering of the extracted
subtitle data at step S5020. The broadcast receiver performs
filtering of detailed information contained in subtitle data, and
outputs the filtered information to a corresponding buffer. In this
case, the subtitle data may be classified as follows according to
values of the `segment type` field.
0x10 Page Composition Segment (PCS) for Base View
0x11 Region Composition Segment (RCS) for Base View
0x12 CLUT definition segment for both Base View and Extended
View
0x13 Object Data Segment (ODS) for Base View
0x14 Display Definition Segment (DDS) for Base View
0x40 extended Page Composition Segment (PCS_EXT) for Extended
View
0x41 extended Region Composition Segment (RCS_EXT) for Extended
View
0x43 extended Object Data Segment (ODS_EXT) for Extended View
0x44 extended Display Definition Segment (DDS_EXT) for Extended
View
The broadcast receiver decodes subtitle display information for a
base view from the classified DDS, PCS, RCS, and ODS at step S5030.
The broadcast receiver decodes the DDS, the PCS, the RCS, and the
DDS, so that it can obtain size information of a subtitle to be
displayed, position information of the subtitle, object
configuration information, object's unique information, and the
like. Information needed for the broadcast receiver to display a
subtitle at a base view may also be called subtitle control
information.
The broadcast receiver decodes the ODS, and parses a Color Look Up
Table (CLUT), so that it determines subtitle display color
information at a base view at step S5040. The broadcast receiver
decodes `pixel-data_sub-block` data contained in the ODS, so that
it can acquire a pseudo-color value of a subtitle to be displayed
on a base view graphic plane. The broadcast receiver parses the
CLUT, so that it can convert the pseudo-color value into
information of a color to be actually displayed.
The broadcast receiver decodes extended subtitle display
information for the extended view from the extended DDS, the
extended PCS, the extended RCS (or RCS), and the extended ODS (or
ODS) at step S5050. The broadcast receiver decodes the extended
DDS, the extended PCS, the extended RCS, and the extended ODS (or
ODS), so that it can recognize size information of a subtitle to be
displayed, position information of the subtitle, object
configuration information, object's unique information, and the
like. Information needed for the broadcast receiver to display a
subtitle at the extended view may also be referred to as extended
subtitle control information as necessary.
The broadcast receiver decodes the extended ODS (or an ODS), and
parses a CLUT, so that it determines subtitle display color
information at a extended view at step S5060. The broadcast
receiver decodes `pixel-data_sub-block` data contained in the
extended ODS (or an ODS), so that it can acquire a pseudo-color
value of a subtitle to be displayed on the extended view graphic
plane. The broadcast receiver parses the CLUT, so that it can
convert the pseudo-color value into information of a color to be
actually displayed.
In a 3D display, a color of a left view subtitle may be equal to a
color of a right view subtitle. In this case, the broadcast
receiver may determine only once the color information of a
subtitle to be displayed, and may use subtitle color information of
other viewpoint by reading the determined color information. In
this case, step S5060 may herein be omitted or a process for
copying or reading the color information that has been determined
at step S5040 may be carried out.
The broadcast receiver controls a subtitle for the base view and a
subtitle for the extended view according to individual subtitle
control information, and outputs the controlled subtitles at step
S5070. The broadcast receiver outputs the base view subtitle along
with base view video data according to subtitle control information
and outputs the extended view subtitle along with extended view
video data according to extended subtitle control information, so
that it can display a 3D subtitle.
In the above-mentioned steps, the step for processing subtitle
display information for a base view subtitle and the other step for
processing extended subtitle display information of an extended
view subtitle need not always be carried out in the above order. If
necessary, subtitle display information for the extended view may
be first carried out, or subtitle display information for the base
view and subtitle display information for the extended view may be
simultaneously carried out.
FIG. 6 is a block diagram illustrating a broadcast receiver for
receiving and processing 3D subtitle data according to one
embodiment of the present invention.
Referring to FIG. 6, the broadcast receiver includes a
demultiplexer (denoted by `MPEG2 TS Demux (PID filter)`) 6010, a
section filter 6020, an Extended View (EV) subtitle decoder 6030, a
Base View (BV) subtitle decoder 6040, a composition buffer 6050, a
CLUT processor (denoted by `CLUT`) 6060, an EV pixel buffer 6070, a
BV pixel buffer 6080, and a 3D graphics controller 6090.
Constituent components of the broadcast receiver shown in FIG. 6
will hereinafter be described in detail. In more detail, the
broadcast receiver shown in FIG. 6 is designed to receive and
process the 3D subtitle data shown in FIG. 5. The same or
duplicated parts as those of FIG. 5 will be briefly descried.
In the broadcast receiver, a receiving unit (not shown) receives a
Moving Picture Expert Group 2 Transport Stream (MPEG2 TS) including
subtitle data, and the demultiplexer 6010 performs filtering of the
received MPEG2 TS using a PID corresponding to subtitle data so
that it extracts and outputs subtitle data.
The section filter 6020 performs section-filtering of subtitle
data, so that it outputs PCS, PCS_EXT, RCS, RCS_EXT, DDS, DDS_EXT,
ODS, ODS_EXT, and Color Look Up Table Definition Segment (CLUTDS)
data.
In the following description, the demultiplexer 600 for extracting
subtitle data from the received broadcast signal and the section
filter 6020 for extracting and outputting display information and
CLUTDS of a subtitle may be contained in one extraction unit as
necessary.
In this case, PCS, RCS, DDS, ODS, PCS_EXT, RCS_EXT, DDS_EXT, and
ODS_EXT may be buffered in the composition buffer 6050, and the
buffered results may be applied to the 3D graphics controller 6090.
In addition, PCS, RCS, DDS, and ODS may be applied to the BV
subtitle decoder 6040, and PCS_EXT, RCS_EXT, DDS_EXT, and ODS_EXT
may be applied to the EV subtitle decoder 6030.
The CLUT processor 6060 processes the CLUTDS, so that it outputs
display color information to the BV pixel buffer 6080 and the EV
pixel buffer 6070.
The BV subtitle decoder 6040 decodes PCS, RCS, DDS, and ODS, so
that it decodes subtitle data for the base view and subtitle
display information for the base view and outputs the decoded
subtitle data and the decoded subtitle display information to the
BV pixel buffer 6080. The EV subtitle decoder 6030 decodes PCS_EXT,
RCS_EXT, DDS_EXT, and ODS_EXT, so that it decodes subtitle data for
the extended view and subtitle display information for the extended
view and outputs the decoded subtitle data and the decoded subtitle
display information to the EV pixel buffer 6070.
The 3D graphic controller 6090 receives PCS, RCS, DDS, ODS,
PCS_EXT, RCS_EXT, DDS_EXT, and ODS_EXT from the composition buffer
6050, and receives subtitle display information for the base view,
ODS and color information for the base view from the BV pixel
buffer 6080. The 3D graphics controller 6090 receives subtitle
display information for the extended view, ODS_EXT and color
information for the extended view from the EV pixel buffer 6070.
The 3D graphics controller 6090 reads the received information, so
that it controls subtitles of respective viewpoints and outputs the
controlled subtitles.
In accordance with another embodiment of the present invention, the
BV subtitle decoder 6040 decodes the ODS and the EV subtitle
decoder 6030 decode the ODS_EXT, so that the BV subtitle decoder
6040 and the EV subtitle decoder 6030 acquire information of a
displayed subtitle object. The 3D graphics controller 6090 receives
coordinates-, size-, and configuration-information (for example,
PCS, RCS, DDS, PCS_EXT, RCS_EXT, and DDS_EXT) of a displayed
subtitle object, so that it may control the 3D subtitle display
using the received information.
The method disclosed in the present invention may be implemented in
the form of program commands executable by a variety of computer
means, and recorded on a computer-readable recording medium. The
computer-readable recording medium may include program commands,
data files, data structures, etc. individually or in combination.
The program commands recorded on the medium may be ones specially
designed and configured for the present invention or ones known and
available to those skilled in computer software. Examples of the
computer-readable recording medium include magnetic media such as a
hard disk, a floppy disk and a magnetic tape, optical media such as
a compact disc read only memory (CD-ROM) and a digital versatile
disc (DVD), magneto-optical media such as a floptical disk, and
hardware devices specially configured to store and execute program
commands, such as a ROM, a random access memory (RAM) and a flash
memory. Examples of the program commands include high-level
language codes that may be executed by a computer using an
interpreter, etc., as well as machine language codes such as those
produced by a compiler. The above-stated hardware devices may be
configured to operate as one or more software modules to perform
the operation of the present invention, and vice versa.
Although the present invention has been described in conjunction
with the limited embodiments and drawings, the present invention is
not limited thereto. Those skilled in the art will appreciate that
various modifications, additions and substitutions are possible
from this description. Therefore, the scope of the present
invention should not be limited to the description of the exemplary
embodiments and should be determined by the appended claims and
their equivalents.
MODE FOR THE INVENTION
Various embodiments have been described in the best mode for
carrying out the invention.
INDUSTRIAL APPLICABILITY
As apparent from the above description, embodiments of the present
invention may be wholly or partially applied to a digital
broadcasting system.
It will be apparent to those skilled in the art that various
modifications and variations can be made in the present invention
without departing from the spirit or scope of the invention. Thus,
it is intended that the present invention cover the modifications
and variations of this invention provided they come within the
scope of the appended claims and their equivalents.
* * * * *