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Publication numberCA2837461 C
Publication typeGrant
Application numberCA 2837461
Publication date16 Jun 2015
Filing date6 Oct 2000
Priority date8 Oct 1999
Also published asCA2322909A1, CA2322909C, CA2575035A1, CA2575035C, CA2575037A1, CA2575037C, CA2575038A1, CA2575038C, CA2627816A1, CA2627816C, CA2628000A1, CA2628000C, CA2629277A1, CA2629277C, CA2630140A1, CA2630140C, CA2688848A1, CA2688848C, CA2688849A1, CA2688849C, CA2688851A1, CA2688851C, CA2688917A1, CA2688917C, CA2688918A1, CA2688918C, CA2688919A1, CA2688919C, CA2688931A1, CA2688931C, CA2688933A1, CA2688933C, CA2689061A1, CA2689061C, CA2689063A1, CA2689063C, CA2689070A1, CA2689070C, CA2730358A1, CA2730358C, CA2730368A1, CA2730368C, CA2730576A1, CA2730576C, CA2730840A1, CA2730840C, CA2767311A1, CA2767311C, CA2776412A1, CA2776412C, CA2776418A1, CA2776418C, CA2776605A1, CA2776605C, CA2776645A1, CA2776645C, CA2776655A1, CA2776655C, CA2796906A1, CA2796906C, CA2796926A1, CA2796926C, CA2797143A1, CA2797143C, CA2797145A1, CA2797145C, CA2797146A1, CA2797146C, CA2824560A1, CA2824560C, CA2824562A1, CA2824562C, CA2824564A1, CA2824564C, CA2824634A1, CA2824634C, CA2824638A1, CA2824638C, CA2837460A1, CA2837460C, CA2837461A1, CA2837617A1, CA2837617C, CA2837633A1, CA2837633C, CA2837640A1, CA2837640C, CA2837643A1, CA2837643C, CA2837675A1, CA2837675C, CA2837908A1, CA2837908C, CA2837910A1, CA2837910C, CN1187981C, CN1305309A, US7051359, US7051361, US7073194, US7080401, US7100189, US7448064, US7448065, US7469415, US7603695, US7620972, US7620973, US7735112, US7748024, US7757266, US7779447, US7779448, US7802289, US7814529, US7814530, US7831994, US7882534, US7882535, US7882536, US7886331, US7958538, US8347330, US8539521, US8539522, US8544041, US8555307, US8640155, US8677405, US8683506, US8701142, US8707344, US8707345, US8707356, US8707367, US8707368, US8726333, US8732752, US8739209, US8752082, US8782695, US8898699, US8910204, US8910205, US8938754, US8966529, US8978063, US8984553, US8997147, US9003444, US9003469, US9015752, US9015753, US9015754, US9021523, US9021524, US9032436, US9038101, US9043836, US9078032, US9084009, US9088806, US9113179, US9124927, US9124938, US9294812, US9300988, US9307271, US9307282, US9351042, US9525915, US9525916, US20040244052, US20040250290, US20040268382, US20040268411, US20040268412, US20050005307, US20050163148, US20080075105, US20080080546, US20080083007, US20090172735, US20090178076, US20090178077, US20090219448, US20090219450, US20090222856, US20090322965, US20100031289, US20100058392, US20100122298, US20100122299, US20100169922, US20100169923, US20100169924, US20110187923, US20120137331, US20120144431, US20120144432, US20130010200, US20130010201, US20130010202, US20130014204, US20130081086, US20130219450, US20130298165, US20130305284, US20130305309, US20130305310, US20130312036, US20130339995, US20130340008, US20130340010, US20130347042, US20140089974, US20140089975, US20140089976, US20140089977, US20140089978, US20140259064, US20140259066, US20140259076, US20140259077, US20140351856, US20140366077, US20140373056, US20140373058, US20140373059, US20140373060, US20140373068, US20140373069, US20140373072, US20140373083, US20140373084, US20150135215, US20150143428, US20150143429, US20150195610, US20150195622, US20150319483, US20150319495, US20150319496, US20150350695, US20150350696, US20150358673, US20150365718, US20170064392
Publication numberCA 2837461, CA 2837461 C, CA 2837461C, CA-C-2837461, CA2837461 C, CA2837461C
InventorsJin Pil Kim
ApplicantLg Electronics Inc., Jin Pil Kim
Export CitationBiBTeX, EndNote, RefMan
External Links: CIPO, Espacenet
Virtual channel table for a broadcast protocol and method of broadcasting and receiving broadcast signals using the same
CA 2837461 C
Abstract
A virtual channel,table for broadcasting protocol and a method for broadcasting by using the virtual channel table includes identification information identifying and permitting discrimination of active and inactive channels contained in the virtual channel table. At a receiver, the virtual channel table transmitted from the transmitting side Is parsed, thereby determining whether the current received channel is an active or inactive channel.
Claims(5)
CLAIMS:
1. A method of processing a digital broadcasting signal in a digital television receiver, comprising:
demodulating a digital broadcasting signal including program and system information protocol (PSIP) data including a virtual channel table (VCT), and outputting demodulated PSIP data, wherein the VCT includes a predefined data field which is set to zero for an inactive charmel, wherein the inactive channel is a channel that is not presently carrying a broadcast program; however, the same inactive channel is scheduled to carry a broadcast program at a predetermined later time from a broadcasting station without local viewer interaction; and processing display of the corresponding virtual channel, wherein when the virtual channel is currently inactive, the receiver is capable of skipping over the virtual channel while a user is surfing, wherein the VCT further includes a table_id field, wherein the VCT further includes a current_next_indicator field, wherein the VCT further includes a minor_channel_number field, wherein the VCT further includes a access_controlled field, and wherein the PSIP data further includes a System Time Table (STT).
2. The method of claim 1, wherein the digital broadcasting signal is a digital terrestrial broadcast signal.
3. The method of claim 1, wherein the digital broadcasting signal is a digital cable broadcast signal.
4. The method of claim 1, wherein the predefined data field is included in a statement of a for_loop in a bit stream syntax of the VCT.
5. The method of claim 1, wherein the table_id field is set to 0xC8.
Description  (OCR text may contain errors)

, , VIRTUAL CHANNEL TABLE FOR A BROADCAST PROTOCOL
AND METHOD OF BROADCASTING AND RECEIVING BROADCAST SIGNALS
USING THE SAME
This application is a divisional of Canadian Patent Application Serial No. 2,824,634, which is a divisional of Canadian Patent Application Serial No.

2,796,926, which is a divisional of Canadian Patent Application Serial No. 2,767,311, which is a divisional of Canadian Patent Application Serial No. 2,688,918, which is a divisional of Canadian Patent Application Serial No. 2,628,000, which is a divisional of Canadian Patent Application Serial No. 2,575,037, which is a divisional of Canadian Patent Application Serial No. 2,322,909, filed on October 6, 2000.
BACKGROUND OF THE INVENTION
Field of the Invention The present invention relates to a virtual channel table for a broadcast protocol and a method of broadcasting using the same.
Discussion of the Related Art Generally a program and system information protocol (hereinafter, referred to PSIP) of an advanced television systems committee (hereinafter, referred to as ATSC) standard for digital television broadcasting contains a virtual channel table (VCT).
The PSIP typically contains an electronic program guide (EPG) and system information (SI). The PSIP is defined as the protocol of the ATSC standard for terrestrial and cable digital television broadcasting, which parses encoded messages by using a moving picture experts group-2 (MPEG-2; ISO/IEC 13818-1) system to thereby provide various kinds of information on the broadcast programs. This ATSC standard is described in "Program and System Information Protocol For Terrestrial Broadcast and Cable", ATSC
Document A/65, 23 DEC 1997.

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audio/vidp 4ata With MPEG-2' video and 4C..- audio .formats., = = .
, . .
. . .
= -and. contains several tables for.transmitting information on . ' = .
the channel of each broadcasting Station, .and information on . ' = ' .
=
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-. . 5 the.programs on each channel: The PSIP has .a. primary .
, . function of, conducting the 'audio and. video pervices'of the " ' = -,broadcast corresponding to a desired. channel, and an . .. , .= , . .
. -.additional function of conducting the electronic program =
: - =
service for the broadcast programs.
.-= =
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. 10 ' The Channel information for the channel selection =
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and ..the packet identification (PIM, information for , . .
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reception of the.audio and video' data are cOntained'in a .
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. = . - virtual channeltsbld (VCT), and the eleCtronic,program ' - = , .
. , . .
. bervice.infOrmation on the broadcast programs on each -. .
. 15' channel is contained in, an .even information -table OUT).=
. . =
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Aliso, the PSI?., a system WM for' .
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. information', a rating region table (RRT) for transmitting ' . = .
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. information on the.region.and organizatiom,for program = . . .
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.. = . 'rating, an.6xtended text table. uni3 for providing. an . = = .
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-additional=explanation On,the channel and broadcast. program;
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an a' master guide table' for management of the version -.
, . of 'each table-mentioned' above and the packet identification:
.
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. =
(PXD). these tabled are transmitted in data units, which.
:-= ' ' are called sections. Namely, all of the tables have one or . .
.
.
- . 25. more sections.. as a basic. unit..
. .
. . = . -= . . ..=. = ' = =
' = Sy way of example, the Virtual. channel table may . .
:
= .
= be divided into. 256 sections. A single section may Contain.
. .
Information on several virtual channels,. but information for ' , = .
_ = a single 'virtual channel may.not=be spread over on two' . or = ' i .
. 30. more -Sections.-. . = . .
= .
. . .
' .
. .
. .
. .
-= = - . - -.Fig. 1..is aAliagram illustrating the bit stream -.
.
- - .
syntax of a general virtual channel table for terrestrial -, -, = .
= ,_= = . . -2- . . . = =
.
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=
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74420-21D9 =
broadcast, which' has been described in the abOve-mentioned *= document A/65. The general virtual channel table contains a transpoxt stream identifier, a major channel number, a minor.
channel number, a-short channel name, a carrier frequency, a program number and the like, and contains additional -information in*the descriptor(s) thereof..
Referring to Fig. 1, the virtual channel table has the table identifier field of "OxC8", and the value of the = packet identification (PID) for the virtual channel table is "Ox1FFB". The version number field "version number"
=
represents the version value of the virtual channel table, the section number field "section number" represents a corresponding section number, the last section number field =
"last section number" represents a last section number of the virtual-channel'table, and the section number channel field "num channels _ in section" represents the number of _ ' = whole virtual channels existing within the Sections of the virtual channel table.
.The short name field "short:name" within the . .
statement in the "for loop" represents the name of the ' =.virtual channel,- and the major channel number field =
"major channel number" represents a major channel number.
=
among the virtual.Channels defined in the statement mentioned above. Each virtual channel number is connected to the major and minor channel numbers, respectively, .and =
'the major and minor channel numbers *function as the user =
= reference number for the corresponding virtual channel. ,In=
other words, the virtual channel table carries the data for each=virtual channel through the statement of the "for loop". =
=
The program number field "program number" contains the information for connecting the virtual channel where the=
=

-3---=
= =

=
=
=
74420-21D9 =
MPEG-2 program association table (PAT) and prOgram map table (PMT) are defined, which corresponds to the program numbers = in the program association table and the program map table.
, In this case, the program association table defines the components of:the program for every program number, namely, indicates the packet identification of the .transport packet = transmitting the program map table. The program map table defines the list and the annex information thereof on the =
packet identifiCation, of the = -.
.
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- =
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=

CA 02837461 2013-12-19 =

=
transport packet transmitting the program identification number and the bit stream of the. = =
video and audio signals constituting the=program.
= =
The source identifier field "source_id" represents the program source connected to the. =
.= .corresponding virtual channel. In this case, the source means a specific source such as image, -text, data or sound. The source identifier field-"source id " has a unique value in the transport.
streamtransinitting the virtual channel table. The descriptor length field "descriptOrsiength"
- indicates the whole length of the descriptors of the corresponding virtuat channel, and the = additiOnal descriptor length field "additional descriptorsiength"
indicates the whole length .=
of all of the additional descriptors of the.virtual channel table.
. =
. - Fig. 5 shows an exemplary list of descriptors for PSIP tables according to the ATSC
. . =
standard.
. .
=
ơ
Fig. 2 is a diagram illustrating an example of execntingscheduled broadcasting by t =
-using four virtual-channels in a broadcasting .station.
. By way of example, it is-assumed that the scheduled broadcast as shown in Fig. 2 is executed through the four virtual channels, 51-1, 51-2, 51-3 and. 51-8 in an arbitrary broadcast station and a virtual channel table composed of a single section is transmitted.
. .
If the current time is 20;15, the system time table transmits the.current time information. In this case, the channels 51-1 and 51-3 .broadcasting at the current time 20:15 are defined as the active channels. =
=
.20. On the other hand, the channel 51-2 is not broadcasting at the current time and is going to be broadcast the next day, and the channel 51-8 is going to be broadcast next at 06:00. In this case,, the channels 51-2 and 51-8, which are not broadcasting at thecurrent time =
=
= =
=
=
=

==

, = =
= .
200.5 and are going to be broadcant=in the future, are -'defined an the. inactive channels.
=
=
=
As a. result, each channel may be an active or =
= inactive channel, based.upon an arbitrary point in time. .
Within the PSIP, the virtual channel table should contain the active- channels as required and may also contain'.
=
=
=
the inactive channels as recommended facts, for conducting =
= the electronic program guide:
==Therefore, at.the current time 20:15 the virtual channel table may. contain information on all of the channels .
= 51-1, 51-2, 51-3 and 51-8, and thue a digital television '-broadcast receiver or a. digital cable broadcast receiver ' = .
receives the virtual channel table to.thereby.provide the = -... =
=- channel delection information to TV viewers.
15- However, as shown in Fig. .1, according to the bit stream. syntax of the virtual Channel table according to the .
. .
A165 standard tfie digital television broadcast receiver or "
=
tht'digital-cable.broadcast'receiver cannot discriminate = = between the active channels (for example, the channels 51-1 -20¨and 51-3) and the inactive channels (for example, the channels . 51-2 and.51-8);..when parsing-the-virtual channel table.
.
=
O.
=
.An a-consequence, the. TV viewers see a black = screen because of the 'information on. the Inactive channels transmitted..from the broadcast station for providingthe . .
25 electronic program guide. The black screen means the black = background. color is displayed on the screen when an. inactive.
. .
channel not broadcasting at a current time is selected. On .
the other hand, the character message "service not provided"
is displayed on the screen of the black background color by 30 the on-screen display function of the digital television =
broadcast receiver or the digital cable broadcast=receiver.
. .
By way of example, if the TV viewer selects- the channel 51-2 = =
=
=
= =

. .
74420-21D9 =
- with a channel up .key while viewing the channel 51-4, the -= audiO and video data are not displved because the channel 51-2. is an inactive, channel, such that. the black background = color is dispIayed.on-the screen.
. .
The above-mentioned problem may give many = =
= =
inconvenience to the 'TV viewers at a point of time when digital television broadcast receivers or digital cable broadcast. receivers become popular and a.large number 'of virtual channels are broadcast.
: SUMMARY OF THE 'INVENTION
= =
Accordingly,- some embodiments of the present invention are directed to a virtual channel table that.
substantially obviates one or more of the problems due to limitations and disadvantages of the related art.' - 15 An object of-some embodiments of the present = =
. invention is to provide a virtual channel table tor a broadcast protocol, and a method of broadcasting by using=
=
. the.' same table, which are capable of identifying-and .
permitting discrimination between active and inactive = . .20 channels from the channels received by a broadcast reCeiver.
=
Another object of some embodiments of the .
=
=
invention is to provide a virtual channel table for a . *
broadcast protocol, "and a method of-broadCasting.by using =
the same table, which are capable of rapidly displaying only = 25 the channels being broadcast at a current time.
=
.
.
Additional features andadvantages of embodiments =
of the invention will be set forth in the description which =
follows, and in part will be apparent from the description, - or may be learned by.practice of the invention. The 30 objectives and other advantages of the invention will'be =
=
= ==
=
= =

realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
According to one aspect, there is provided a method of processing a digital broadcasting signal in a digital television receiver, comprising: demodulating a digital broadcasting signal including program and system information protocol (PSIP) data including a virtual channel table (VCT), and outputting demodulated PSIP data, wherein the VCT
includes a predefined data field which is set to zero for an inactive channel, wherein the inactive channel is a channel that is not presently carrying a broadcast program; however, the same inactive channel is scheduled to carry a broadcast program at a predetermined later time from a broadcasting station without local viewer interaction; and processing display of the corresponding virtual channel, wherein when the virtual channel is currently inactive, the receiver is capable of skipping over the virtual channel while a user is surfing, wherein the VCT further includes a table_id field, wherein the VCT further includes a current next indicator field, wherein the VCT further includes a minor_channel_number field, wherein the VCT further includes a access_controlled field, and wherein the PSIP data further includes a System Time Table (STT).
The identification information may be loaded on or included in at least one reserved field in the virtual channel table. Preferably, the identification information assigns at least one or more bits of a reserved field as a =
= =
= . =
,.
.
, .
1, thereby indicating that a'corresponaing Channel is an inactive, channel. =
=
For example, the value of the program number field =
'program number" in the virtual channel table is set to "0", =
= 5 .thereby indicating that the corresponding channel is the inactive channel.. .
The identification information seta the value 'of . the number elements field "number_elements" (which indicates =
the number of PID's used for a' program) of the service position descriptor field "service_locationLdescriptor"
.(which is used to list available bit' streams by their PID's) in the virtual channel table to "0", thereby indicating that;
the corresponding c4annql is an inactive channel.
, . In.a.case where the corresponding -channel is an =
inabtive channel,.the virtual channel.table does not contain the service location descriptor field therein, 'for the -purpose of indicating that the corresponding channel is an inactive channel.
=
It is to be understood that both the foregoing =
.general description andthe'lollowing detailed description =
= =
=
are exemplary and' explanatory and are intended to provide =
further explanation of the invention as claimed.
=
BRIEF DESCRIPTION OF THE DRAWINGS
=
=
The.accompanying drawings,.which are included to '=
. provide a further underatapding of the invention and are incorporated in and constitute a part of this specification, .
illustrate embodiments of the:invention and together with the =
description serve to explain the principles of embodiments of .
the invention. =
=
= =
= = 9 .
=
= =
= =

In the drawings: = *
FIG. 1 is a diagram illustrating the. bit stream syntax of a general virtual channel table for terrestrial =
broadcast;
= . =
= .
=
FIG. 2 is a_.diagram= illustrating an example of executing schedule broadcasting by using four virtual =
=
channels in.a broadcast Station;
=
' FIG.. 3 is a diagram illustrating the bit stream =
== = syntax of a virtual channel table for terrestrial broadcast.
= 10 according to an embodiment of the present invention;
=
FIG. -4 is a diagram-illustrating the bit stream : syntax of a virtual channel table for cable according to =
= .another embodiment of the present invention; and .
=
FIG. 5 is chart listing, various descriptors available according to a program and system information = protocol of an advanced television systems committee =
=
. standard digital television broadcast..
=
DETAILED DESCRIPTION OF THE: PREFERRED EMBODIMENTS =
=
=
Reference will now be made in detail to the -.20 preferred embodiments of the present invention, examples of .
which. are illustrated in the accompanying' drawings.
According. to the present invention, a virtual = .channel 'table' for a broadcast protocol comprises identification information capable of identifying and .
permitting discrimination between active and inactive channels in the bit stream syntax thereof. A' transmitting side, namely, a broadcast station transmits the virtual channel table having the identification information to the receivers. Each of the receivers parses the virtual channel =
io =
= =

= =
= -= = =
.
.
table received, thereby determining whether the channel =
=
currently Selected is an active channel or an inactive.
=
=
channel..
= =
The identification information, which is. capable =
= 5 . of identifying and permitting discrimination between an.
active channel and an inactive channel under the standard of =
the loSIP, is contained in at least one field of the virtual .
channel table: of the above protocol,.puch that only active' . = .
channels being currently broadcast are displayed to TV
. 10 .viewers. =
=
.4 =
=
=
Hereinafter, preferred embodiments of a virtual =
=
channel table and a method according to the present =
= 'invention .will be in. detail described With reference to Figs. 3and4.
15 = In order for a-digital television receiver and a .digital.cable broadcast receiver to parse the virtual .
Channel table:and.thus to ,determine whether the channel selected currently is an. active channel or an inactive channel, the bit Streamsyntax.of the virtual channel table .
20 may be corrected. =
:
For example, = the fact that channels' 51-2 and 51-8 are not broadcast at the current time 20:15, but are going =
tq be. broadcast in the future, should be ecognized in a - digital television receiver' and a cable broadcast receiver. -25- In a preferred, embodiment, the identification information capable of identifying an inactive channelis contained in =
' the pr6gram nuMber field "program_number", the service location' descriptor field "service location descriptor"
.and/or Other reserved fields contained in the bit stream 30 syntax.of the virtual channel table.
=
=
=
2 11 =
=
=
=

.
Fig. Yis a diagram illustrating the .bit stream_ syntax of a. virtual Channel table for terrestrial broadcast according to an embodiment of the present invention. To . indicate that a corresponding channel is an inactive channel, the value of the program number field "program number" is set to "0". And, since there are no audio and video signals.of the current service location _ descriptor, the value of. the number elements field "number elements" of the service location descriptor "service_location_descriptor".is set to "0". Also, or =
alternatively, to indicate that the corresponding Channel is =
=
an inactive channel, the service location descriptor =
"service location descriptor" (see Fig. 5) kb not contained.
= in the virtual channel table. In other words, for the digital television receiver and the cable broadcait - . receiver, the sewice location descriptor field should be . =
contained in the virtual channel table only in a case where =
=
the corresponding channel is the active channel. If the corresponding channel is an inactive channel, however, the-.
service location descriptor field is not contained in the = = =
.virtual channel table.
= . .
In a preferred embodiment, in.order to recognize the fact that the corresponding channel is an inactive channel in a more apparent manner, 1 bit of the reserved =
=
field of 6 bits for. each channel is assigned to define -a =
flag indicative of an inactive channel. In,the preferred .
. embodiment, -I bit in the reserved field between the hidden =
field "hidden" and the service type field !Iservice_type" in the statement of the."for_loops! is assigned to define a flag =
=

. .
, =

74420-21D9 = . , =
indicative of an inactive channel. For. example, 'in a caSe.
where the flag indicative of the inactive channel Is "1", .the corresponding channel is an active channel, and if the flag is "0", the corresponding channel is an inactive channel.
In the preferred embodiment, the above three cases may be added as requirements to the A/65 standard. Any of all of the three cases may be added to the A/65 standard.
=
=
As mentioned above, since the information on an inactive channel is contained in the. virtual channel table, the digital television receiver can determine whether the virtual channel currently received is an active channel or an inactive channel by parsing only the virtual Channel table. For examplelif the value of.the program number . 15 field "program_number" in the virtual channel table is "0";
.if the value of the information on the inactive channel defined by assigning a predetermined bit in the reserved =. field is "0", or if the service location descriptor field "service location descriptor" is not contained in the .virtual channel table, the Major channel number field "major channel number" and the minor channel number field "minor channel number" defined in the bit stream syntax of =
the virtual channel table currently transmitted can be used to determine that the current virtual channel is an inactive channel for example by both being assigned a value of "0".
.0n the-other hand, if an. inactiye channel has been = determined under the. above process, the digital television receiver can skip the inactive channel, without displaying it-on =
=
12a = =

=
= = = '' =
= =
74420-21D9 = . =
=
= '- ' the screen, upon channel conversion by means of a channel up key or a chatmel down key: .
. . .
= =Fig. 4 is a diagram illustrating the bit stream syntax of a virtual channel table for cable aCcording to another embodiment. /.1+.3 shown, the -virtual amulet table may be.applied to = = = .
= - cable broadcasting in the same manner as ftboy.e, - . =
As is apparent from-the foregoing description, a virtual channel table for a broadcast protocol, ,ad a method of broadcasting by using the virtual channel table are capable of = =
including the identification information capable of identifying and -perMitting discrimination between active and inactive channels in a tianstnitting side, and in a receiving side parsing the virtdal channel table to thereby determine whether the channel currently=selected is the active, =
= 10 channel or the inietive channel. Therefore, inactive channels may. be skipped, without being = .
displayed, upon the channel conversion by using a channel up key or a channel down key, such that the TV viewer can enjoy channelsurfing in a convenient manner, without viewing a =
= = .blick screen. Irl addition, the virtual channel table May be transmitted, while containing-the inactive channels 'therein, thereby making it posiible to provide a more abundant electronic = 15 program service.
= = It will be apparent to those skilled in the art that varions modifications and vaiiations can be made to the embodimdnts described herein. =
=
Thus, it is intended that the th 'present invention coVere Modifica. dons and =
=
. .
==variations of this invention provided they come within the t copeqf the appended claims and . -=
20 their equivalents.
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Legal Events
DateCodeEventDescription
27 Jan 2014EEERExamination request
Effective date: 20131219