Multi-channel television system with viewer-selectable video and audio

Claims

I claim:

1. A method for communicating a packetized data stream including video data corresponding to a primary signal and at least first and second alternative video signals which are associated with said primary signal, said primary signal being associated with a first channel designator, comprising the steps of:

providing control data in said packetized data stream which associates said primary signal and said first and second alternative video signals;

transmitting said packetized data stream to a terminal;

reproducing said primary signal on an output device which is associated with said terminal during a first time period under said first channel designator;

at an end of said first time period, using said control data to provide an on-screen display on said output device to assist a user in selecting one of said first and second alternative video signals for reproduction on said output device during a second time period which follows said first time period; and

mapping the selected alternative video signal to said first channel designator to allow the selected alternative video signal to be displayed on said output device under said first channel designator.

2. The method of claim 1, wherein said selected alternative video signal is said first alternative video signal, at least third and fourth alternative video signals are associated with said first alternative video signal, and said control data associates said first alternative video signal with said third and fourth alternative video signals, comprising the further steps of:

reproducing said first alternative video signal on said output device during said second time period in response to said user command;

at an end of said second time period, using said control data to provide an on-screen display on said output device to assist the user in selecting one of said third and fourth alternative video signals for display on said output device during a third time period which follows said second time period; and

mapping the selected third or fourth alternative video signal to said first channel designator to allow the selected third or fourth alternative video signal to be reproduced on said output device under said first channel designator.

3. The method of claim 1, wherein:

said primary signal comprises a first part of a story line, and said first and second alternative video signals comprise alternative second parts of said story line.

4. A method for processing a packetized data stream which is transmitted to a terminal, said packetized data stream including video data corresponding to a primary signal and at least first and second alternative video signals which are associated with said primary signal, said primary signal being associated with a first channel designator, comprising the steps of:

recovering control data at said terminal from said packetized data stream, said control data associating said primary signal and said first and second alternative video signals;

reproducing said primary signal on an output device which is associated with said terminal during a first time period under said first channel designator;

at an end of said first time period, using said control data to provide an on-screen display on said output device to assist a user in selecting one of said first and second alternative video signals for reproduction on said output device during a second time period which follows said first time period; and

mapping the selected alternative video signal to said first channel designator to allow the selected alternative video signal to be reproduced on said output device under said first channel designator.

5. The method of claim 4, wherein said selected alternative video signal is said first alternative video signal, and at least third and fourth alternative video signals are associated with said first alternative video signal, and said control data associates said first alternative video signal with said third and fourth alternative video signals, comprising the further steps of:

reproducing said first alternative video signal on said output device during said second time period in response to said user command;

at an end of said second time period, using said control data to provide an on-screen display on said output device to assist the user in selecting one of said third and fourth alternative video signals for reproduction on said output device during a third time period which follows said second time period; and

mapping the selected third or fourth alternative video signal to said first channel designator to allow the selected third or fourth alternative video signal to be reproduced on said output device under said first channel designator.

6. The method of claim 4, wherein:

said primary signal comprises a first part of a story line, and said first and second alternative video signals comprise alternative second parts of said story line.

7. A terminal for processing a packetized data stream which is transmitted thereto, said packetized data stream including video data corresponding to a primary signal and at least first and second alternative video signals which are associated with said primary signal, said primary signal being associated with a first channel designator, comprising:

means for recovering control data at said terminal from said packetized data stream, said control data associating said primary signal and said first and second alternative video signals;

means for reproducing said primary signal on an output device which is associated with said terminal during a first time period under said first channel designator;

means for using said control data to provide an on-screen display on said output device at an end of said first time period to assist a user in selecting one of said first and second alternative video signals for reproduction on said output device during a second time period which follows said first time period; and

means for mapping the selected alternative video signal to said first channel designator to allow the selected alternative video signal to be reproduced on said output device under said first channel designator.

8. The terminal of claim 7, wherein said selected alternative video signal is said first alternative video signal, and at least third and fourth alternative video signals are associated with said first alternative video signal, and said control data associates said first alternative video signal with said third and fourth alternative video signals, further comprising:

means for reproducing said first alternative video signal on said output device during said second time period in response to said user command;

means for using said control data to provide an on-screen display on said output device at an end of said second time period to assist the user in selecting one of said third and fourth alternative video signals for reproduction on said output device during a third time period which follows said second time period; and

means for mapping the selected third or fourth alternative video signal to said first channel designator to allow the selected third or fourth alternative video signal to be reproduced on said output device under said first channel designator.

9. The terminal of claim 7, wherein:

said primary signal comprises a first part of a story line, and said first and second alternative video signals comprise alternative second parts of said story line.

10. A method for transmitting a primary signal and at least one associated local program signal to a terminal, wherein said primary signal provides a video and audio account relating to an event at a remote location, and said at least one local program signal provides at least one of a video and an audio account relating to said event, comprising the steps of:

transmitting said primary signal from said remote location to a headend of a local television network in a digital packetized data stream;

providing said local program signal at said headend;

providing control data at said headend for associating said primary signal with said local program signal; and

transmitting said control data and said primary and local program signals in said packetized data stream via said local television network to said terminal;

wherein said control data is adapted to be used by said terminal to provide an on-screen display to allow a user to select a video and audio account relating to said event from at least one of said primary signal and said local programming signal for reproduction on an output device associated with said terminal.

11. The method of claim 10, wherein:

said control data is adapted to be used by said terminal to provide an on-screen display to allow a user to select said video account of said primary signal and said audio account of said local program signal for reproduction on said output device.

12. The method of claim 10, wherein:

said control data is adapted to be used by said terminal to provide an on-screen display to allow a user to select said audio account of said primary signal and said video account of said local program signal for reproduction on said output device.

13. The method of claim 10, wherein:

said control data is adapted to be used by said terminal to provide an on-screen display to allow a user to select said video and audio accounts of said primary signal for reproduction on said output device.

14. The method of claim 10, wherein:

said control data is adapted to be used by said terminal to provide an on-screen display to allow a user to select said video and audio accounts of said local program signal for reproduction on said output device.

15. The method of claim 10, wherein:

said primary signal has an associated channel designator; and

said control data is used by said terminal in mapping said local program signal to said channel designator to allow said terminal to recover either of said primary signal and said local program signal for reproduction on said output device under said channel designator.

16. The method of claim 10, comprising the further steps of:

providing an alternative signal which provides an alternative video and/or audio account relating to said event; and

transmitting said alternative signal from said remote location to said headend in said digital packetized data stream;

wherein said control data provided at said headend associates said alternative signal with said primary signal; and

said control data is adapted to be used by said terminal to provide an on-screen display to allow a user to select a video and/or audio account relating to said event from said alternative signal for reproduction on said output device.

17. The method of claim 16, wherein:

said primary signal has an associated channel designator; and

said control data is used by said terminal in mapping said local program signal and said alternative signal to said channel designator to allow said terminal to recover either of said alternative signal and said local program signal for reproduction on said output device under said channel designator.

18. A method for communicating a packetized data stream including data corresponding to a primary signal which provides a first video viewpoint of an event, and at least a first alternative signal which provides an alternative video viewpoint of said event, said primary signal being associated with a particular channel designator, comprising the steps of:

providing a control message in said packetized data stream which designates locations of said first and alternative video viewpoints;

transmitting said packetized data stream to a terminal;

using said control message to provide an on-screen display on an output device associated with said terminal to inform a viewer of said locations to allow the viewer to select a particular one of said first and alternative video viewpoints; and

mapping the selected video viewpoint to said particular channel designator to allow the selected video viewpoint to be reproduced on said output device under said particular channel designator.

19. The method of claim 18, wherein:

said primary data signal comprises first audio data relating to said event, and said alternative signal comprises alternative audio data relating to said event;

said control message provides descriptive information regarding said first and alternative audio data;

said on-screen display informs the viewer of said descriptive information to allow the viewer to select one of said first and alternative audio data; and

the selected audio data is mapped to said particular channel designator to allow the selected audio data to be reproduced on said output device under said particular channel designator.

20. An apparatus for communicating a packetized data stream including data corresponding to a primary signal which provides a first video viewpoint of an event, and at least a first alternative signal which provides an alternative video viewpoint of said event, said primary signal being associated with a particular channel designator, comprising:

means for providing a control message in said packetized data stream which designates locations of said first and alternative video viewpoints;

means for transmitting said packetized data stream to a terminal;

means for using said control message to provide an on-screen display on an output device associated with said terminal to inform a viewer of said locations to allow the viewer to select a particular one of said first and alternative video viewpoints; and

means for mapping the selected video viewpoint to said particular channel designator to allow the selected video viewpoint to be reproduced on said output device under said particular channel designator.

21. The apparatus of claim 20, wherein:

said primary data signal comprises first audio data relating to said event, and said alternative signal comprises alternative audio data relating to said event;

said control message provides descriptive information regarding said first and alternative audio data;

said on-screen display informs the viewer of said descriptive information to allow the viewer to select one of said first and alternative audio data; and

the selected audio data is mapped to said particular channel designator to allow the selected audio data to be reproduced on said output device under said particular channel designator.

22. A method for processing a packetized data stream at a terminal, said packetized data stream including data corresponding to a primary signal which provides a first video viewpoint of an event, and at least a first alternative signal which provides an alternative video viewpoint of said event, said primary signal being associated with a particular channel designator, comprising the steps of:

recovering a control message from said packetized data stream which designates locations of said first and alternative video viewpoints;

using said control message to provide an on-screen display on an output device associated with said terminal to inform a viewer of said locations to allow the viewer to select a particular one of said first and alternative video viewpoints; and

mapping the selected video viewpoint to said particular channel designator to allow the selected video viewpoint to be reproduced on said output device under said particular channel designator.

23. The method of claim 22, wherein:

said primary data signal comprises first audio data relating to said event, and said alternative signal comprises alternative audio data relating to said event;

said control message provides descriptive information regarding said first and alternative audio data;

said on-screen display informs the viewer of said descriptive information to allow the viewer to select one of said first and alternative audio data; and

the selected audio data is mapped to said particular channel designator to allow the selected audio data to be reproduced on said output device under said particular channel designator.

24. A terminal for processing a packetized data stream which is transmitted thereto, said packetized data stream including data corresponding to a primary signal which provides a first video viewpoint of an event, and at least a first alternative signal which provides an alternative video viewpoint of said event, said primary signal being associated with a particular channel designator, comprising:

means for recovering a control message from said packetized data stream which designates locations of said first and alternative video viewpoints;

means for using said control message to provide an on-screen display on an output device associated with said terminal to inform a viewer of said locations to allow the viewer to select a particular one of said first and alternative video viewpoints; and

means for mapping the selected video viewpoint to said particular channel designator to allow the selected video viewpoint to be reproduced on said output device under said particular channel designator.

25. The terminal of claim 24, wherein:

said primary data signal comprises first audio data relating to said event, and said alternative signal comprises alternative audio data relating to said event;

said control message provides descriptive information regarding said first and alternative audio data;

said on-screen display informs the viewer of said descriptive information to allow the viewer to select one of said first and alternative audio data; and

the selected audio data is mapped to said particular channel designator to allow the selected audio data to be reproduced on said output device under said particular channel designator.

BACKGROUND OF THE INVENTION

The present invention relates to a system for processing packetized audio and video data at a television set-top terminal. More particularly, the system allows a television viewer to select specific camera angles and audio feeds of an event which is broadcast by a programming service provider.

Digital transmission of television signals has become increasingly popular since it can deliver video and audio services of much higher quality than analog techniques. Digital transmission schemes are particularly advantageous for signals that are broadcast via a cable television network or by satellite to cable television affiliates and/or directly to home satellite television receivers. It is expected that digital television transmitter and receiver systems will replace existing analog systems just as digital compact discs have replaced analog phonograph records in the audio industry.

However, a substantial amount of digital data must be transmitted in any digital television system. Furthermore, transmission bandwidths and carrier frequencies are often constrained by the need to maintain compatibility with existing equipment. Conventional analog radio-frequency (RF) television programming is transmitted in an assigned 6 MHz bandwidth in the spectrum from 54 to 890 MHz. For example, conventional televisions recognize "channel three" as the designation of the television signal in the spectrum from 60 to 66 MHz, while "channel four" is assigned the spectrum from 66 to 72 MHz. Moreover, in many digital set-top terminals, the received audio/video signal is converted to a predefined spectrum, typically channel three or four, before being provided to the television for display.

While a digital television signal is converted to a television-compatible spectrum at the terminal, the signal may be transmitted to the terminal from the service provider in a variety of ways. For example, the digital transmission may be provided over a cable system, or via satellite at a frequency (e.g., 1.2 GHz) which is well above the terrestrial broadcast band. Transmission within the assigned 6 MHz bandwidth is known as an "in-band" transmission, while transmission outside of this region is known as an "out-of-band" transmission. Moreover, while video and audio data which comprise a television program are transmitted in the 6 MHz band, auxiliary control data for all channels is transmitted out-of-band (e.g., at 75.25 MHz).

Digital transmission techniques are superior to analog techniques since they can use the available spectrum more efficiently. For example, using known digital compression techniques, up to ten conventional television programs may be carried in a 6 MHz bandwidth with standard resolution. Proposed high-definition television (HDTV) systems provide greater resolution but consume additional bandwidth.

One way to transmit compressed digital data to a receiver is in the form of packets contained within a packetized data stream. Typically, the packets carrying the compressed video data will be multiplexed with other packets which, for example, carry corresponding audio data and control information which are necessary to reconstruct a television signal. One standard for transporting digital television signals in this manner is the MPEG-2 standard, details of which can found in document AVC-491, version 1, Apr., 1993 published by the Telecommunications Standardization Sector, Study Group 15, Experts Group 4ATM-Video Coding of the International Organization for Standardization, ISO-IEC/JTC1/SC29/WG11 entitled "Coded Representation of Picture and Audio Information," incorporated herein by reference. Further details of the video syntax and semantics for MPEG-2 video can be found in International Organization for Standardization document ISO/IEC 11172-6 dated Apr. 2, 1993 and entitled "Revised Syntax and Semantics for MPEG-2 Video," also incorporated herein by reference. Also of interest, and incorporated herein by reference, is document MC68VDP/D, a preliminary data sheet entitled "MPEG-2/DCII Video Decompression Processor," .COPYRGT.Motorola Microprocessor and Memory Technologies Group, 1994 which describes a video decompression processor using the MPEG-2 and DigiCipher.RTM. II standards.

In the MPEG-2 system (and the similar DigiCipher.RTM. II system proprietary to General Instrument Corporation, the assignee hereof) a transport stream, or transport multiplex is made up of a contiguous set of fixed length packets. Each packet is 188 total bytes in length, with the first four of those bytes being defined as the packet header. The payload portion of each packet, which includes either video, audio or other data, is thus normally 184 bytes. However, a variable length adaptation field may be provided to extend the header, when required. When an adaptation field is present, the payload portion of the packet will be correspondingly shorter.

Furthermore, various timing and identification information is provided in different portions of the transport stream. These include a packet identifier (PID) found in the transport header of each transport packet to provide a reference number for identifying the transport packets carrying a specific service component. This number is included in a service definition (e.g., service map, or channel map) used by the receiver to identify those transport packets required to reconstruct a television program signal. The PID may also be referenced for various grooming and remultiplexing functions. In the case of video, audio or isochronous control data, the stream of packets labeled with a single PID represents a single video, audio or isochronous data service elementary stream, respectively. Each type of packet will have a different PID identifying the packet type.

The packetized data stream of a programming service is received by a subscriber via a receiver/descrambler that is typically embodied in a set-top terminal. The terminal decompresses and decodes the digital data and provides the corresponding video, audio and data to an output device (e.g., a television, video recorder, and/or separate high-fidelity audio system). In particular, the viewer selects a channel designation (e.g., channel 2) that corresponds to a particular programming service provider (e.g., network X). The channel map data of the packetized data stream maps the data from the channel designator to the corresponding programming service provider. For example, when a viewer selects "channel 2" on the set-top terminal, programming from "network X" will be processed at the terminal and provided to the television at a fixed, pre-defined carrier frequency, for example, in the spectrum from 60 to 66 MHz (television channel 3).

Moreover, data carried in the packetized data stream may be used by a graphics processor in the terminal to provide an on-screen display of available programming. For example, the display may provide a program guide which lists the program name, viewing time and channel. Additionally, such data may be addressed to particular terminals to provide individual account and billing information.

When the viewer selects a particular programming service to view, the corresponding data packets are retrieved and decompressed to allow reconstruction of the corresponding video and audio signal. In particular, data packets with the appropriate PID are demultiplexed, unpacked and provided to a video decompression processor. Finally, the video and audio signals are modulated at a specific carrier frequency and provided to the television for display.

As can be seen, the advent of digital television transmission techniques provides high fidelity video and audio to subscriber's homes, and further provides the opportunity for new services and features for both entertainment and educational purposes. Moreover, such programming presents lucrative marketing opportunities for service providers and others who market programming to specific demographic groups, including, for example, those who enjoy sports programs, movies, children's programs and the like.

However, conventional systems are somewhat constrained by existing television signal spectrum requirements and channel mapping formats. Accordingly, it would be advantageous to provide a digital transmission system for re-mapping the channel assignment of one or more selected audio and video signals of a programming service. Furthermore, such re-mapping should occur according to user-provided commands. Additionally, it would be advantageous to provide a graphical user interface to assist the user in selecting the audio and video signals. The user interface should be able to group the alternative audio and video signals which are associated with a primary channel of a programming service. The system should be able to group additional audio and video signals of an additional programming service provider when, for example, two or more service providers are covering the same event. Furthermore, the system should be compatible with existing packetized data transmission protocols and channel assignment data provided by programming service providers and/or cable system headend operators.

Such a system would have numerous advantageous applications. For instance, a viewer could tune in to a primary channel which was associated with a particular programming service. The programming service could provide additional video and audio choices that the viewer could select. For example, a viewer watching a sports event could select different camera angles and different audio feeds that are provided on the different audio and video signals of the service without tuning away from the primary channel. The selection process could be carried out via an on-screen display (OSD) that is intuitively easy for the viewer to operate. For instance, a display of a football stadium with different color-coded or numbered regions can allow the viewer to easily select the desired viewing angle, thereby providing the sensation that the viewer is actually in the stands.

Furthermore, it would be advantageous for such a system to be arranged so that other channel assignments would remain intact, thereby enabling other viewers to view other primary channels at another television in the same home at the usual pre-assigned channel designation. The present invention provides the above and other advantages.

SUMMARY OF THE INVENTION

The present invention provides a method and apparatus for allowing a television viewer to control the re-mapping of channel assignments in a digital video decoding terminal in order to access alternative video and/or audio signals of a programming service provider.

In particular, a terminal is presented for processing a packetized data stream which includes data from primary and alternative signals of a first programming service (e.g., network X). The primary signal is associated with a first channel designator (e.g., channel 10). The channel designator is used to inform the viewer that he can view a particular programming service at a particular channel which is indicated by the terminal.

The terminal also includes means for mapping the alternative signal to the first channel designator. This means that the alternative signal, such as an audio/video signal, can be found by the viewer at the same channel as the primary channel. The viewer, who has come to associate "channel 10" with "network X" therefore knows that he is still viewing a program of network X, even though he has the opportunity to view and listen to a number of alternative video and audio selections.

The mapping means is responsive to a selection command such as that provided via a microprocessor. The selection command may be a default command that occurs when the viewer does not select alternative audio/video, when the alternative service is not available for a given programming service at a given time, or when the viewer has not been authorized to access the alternative audio/video.

The terminal also includes means for providing the data of the alternative signal to a device for reproduction of a video and/or audio program. This may include, for instance, a video decompression processor and a modulator which provides a signal having a carrier frequency which is compatible with the television or display monitor.

The terminal may also process data from a second programming service (e.g., network Y), which has a second channel designator (e.g., channel 11). The user can select the data of the second programming service to be displayed under the first channel designator (channel 10). This may be useful, for instance, when two or more service providers cover the same event, and the viewer wishes to have unified control of all available audio and video options.

The terminal may include a user interface such as a hand-held remote control unit which is responsive to a user-provided command. If the user does not enter a command to access the alternative audio/video, a default setting in the terminal provides the data of the primary audio/video signal to the television.

In a particularly advantageous embodiment, the terminal includes an on-screen display (OSD) graphics processor which allows the viewer to interact with the terminal via a graphical display to allow the user to select among the available audio/video signals. The user may choose to view both the primary and alternative video signals, for example, in a split-screen or picture in picture format, while listening to only one of the audio signals.