Field of the Invention The present invention relates to improvements in the processing of television signals for output to the user.

Background A conventional television system is illustrated schematically in Figure 1. The system comprises a television network 2 such as a satellite television network in which signals are broadcast wirelessly via one or more satellites, a terrestrial television network in which signals are broadcast wirelessly via one or more land-based repeater stations, or a cable television network.

The system further comprises a set-top box 4 and a television screen 6. Alternatively the components of the two devices 4, 6 can be combined into the same housing to form a television set, but for illustrative purposes the following will be described by reference to an arrangement comprising a separate set-top box 4 and screen 6.

The set-top box (STB) 4 comprises a receiving interface 3 in the form of one or more of: an input for connecting to a radio-frequency antenna for receiving signals over a terrestrial television network, an input for connecting to a satellite dish for receiving signals over a satellite television network, and/or a cable input for receiving signals over a cable television network. The set-top box 4 further comprises a demultiplexer 8 having in input operatively coupled to the interface 3.

The network interface 3 is arranged to receive multiple concurrent television channels, at least in that the physical signals arrive concurrently at the location of the interface. However, only a certain selected signal will be desired by the user. To this end, the demultiplexer 8 is arranged to receive an indication of the selected television channel from the user and to extract the data of that television channel for signal processing and output to the television screen 6. The interface 3 may be arranged to receive a plurality of different television channels on one or more frequency bands. On a given frequency band, the television channels may be interleaved in time into a transport stream comprising multiple channels in different interleaved time slots. In this case the demultiplexer 8 comprises a deinterleaver arranged to extract the data of the selected television program from its respective time slots (note therefore that channels interleaved into a transport stream are considered to be effectively concurrent for the purpose of this application). In the case of multiple frequency bands, the deultiplexer 8 comprises a television tuner arranged to tune to the frequency band of the selected television channel. It is also possible that both time and frequency division multiplexing are used, such that each of a plurality of frequency bands carries a different respective transport stream, the transport stream on each frequency band comprising a plurality of television channels. In this case the demultiplexer 8 comprises both a television tuner and a de-interleaver.

Each television channel comprises one or more elementary streams in the form of: a video stream, one or more audio streams (e.g. two for stereo), and optionally an additional data stream defining program information and/or interactive content. A given television channel is defined by its user content, being a consistent stream of content from the perspective of the user, and may also be identified by a respective television channel identifier in the form of header information.

The set-top box 4 further comprises a signal processing module 10 having an input operatively coupled to the output of the demultiplexer 8, and a television screen output port 12 such as a coaxial output, SCART or HDMI port, etc. operatively coupled to the output of the signal processing module 10. The television channels will have been transmitted over the network 2 in encoded form, e.g. to compress the data of those channels into a smaller number of bits to save on network resources when transmitted over the television network 2. The signal processing module comprises a decoder arranged to decode the content of the selected television channel for output to the screen via the output port 12. The television channels may also have been transmitted in encrypted form to provide security, e.g. so that only authorised users can view them, in which case the signal processing module 10 comprises a decryption algorithm for decrypting, e.g. given an appropriate decryption key.

The signal processing module 10 is preferably implemented in the form of a portion of executable program code stored on a storage medium of the set-top box 4 and arranged for execution on a processor of the set-top box 4. However, the option of some or all of its functionality being implemented in dedicated hardware circuitry is not excluded. The demultiplexer 8 may also be implemented wholly or partially in executable code, though in the case of a tuner it may comprise at least some dedicated tuner circuitry.

Thus a plurality of television channels are concurrently made available in multiplexed form, from which a selected channel is to be demultiplexed, decode and output to a screen 6. Note that the demultiplexing of a television channel from amongst a plurality of television channels made available at the interface 3 by broadcast distinguishes the system from a multicast arrangement such as internet or IP television. A multicast is a point-to-point transmission (albeit point-to-multpoint) whereby each item of content is transmitted to a specific identified recipient terminal in response to a request for the content from that terminal, the transmitter knowing the identify of the recipient terminal and including that identity in header information in the individual transmitted stream. A broadcast on the other hand is transmitted

"indiscriminately" in that multiple television channels are provided to the location of a terminal even if some or all of those television channels have not been requested by that terminal - hence the terminal requires a demultiplexer such as a TV tuner to filter out all but the required television channel (if any). Information identifying the specific recipients would typically also not be included in a broadcast. Conventionally a user selects the desired channel by means of the television 6 or set-top box 4, e.g. using a dedicated infra-red remote control unit (not shown) associated with the television 6 or set-top box 4. The television or set-top box would then demultiplex, decode and output the selected television channel for display on the television screen 6.

Summary

However, the inventors believe there is scope for improvement of this conventional arrangement. Particularly, the conventional arrangement is inefficient in its use of

demultiplexer resources, e.g. requiring a separate television tuner for every terminal upon which the user wishes to view the broadcast.

According to one aspect of the present invention, there is provided a system comprising:

a first terminal comprising (a) a television receiver comprising a receiving interface at which a plurality of concurrent multiplexed television channels are concurrently made available from a television network, each television channel comprising a respective video stream, and a demultiplexer arranged to demultiplex a selected one of said television channels, (b) a signal processing module comprising a decoder arranged to decode the selected television channel, (c) an output for outputting the decoded television channel to a television screen, and (d) a wireless transceiver other than said television receiver; and

a second terminal comprising another screen, a wireless transceiver operable to establish a wireless connection with the wireless transceiver of the first terminal, and a controller configured to receive the video stream of the selected television channel via said wireless connection and to output the video stream of the selected television channel to the screen of the second terminal dynamically as it is received by the television receiver of the first terminal, thus making use of the demultiplexer on the first terminal to demultiplex the selected channel for output of video on the second terminal. In embodiments, the receiving interface may comprise an input from at least one of a satellite dish and a radio-frequency antenna, at which the plurality of television channels are made available on a plurality of different frequency bands, and the demultiplexer may comprise a television tuner operable to tune to the frequency band of the selected television channel, the controller thus making use of the television tuner on the first terminal to demultiplex the selected channel for output of video on the second terminal.

The plurality of television channels may be made available multiplexed in an interleaved form, and the demultiplexer may comprise a de-interleaver, the controller thus making use of the de- interleaver on the first terminal to demultiplex the selected channel for output of video on the second terminal.

The demultiplexer may be configured to demultiplex a selected two of said concurrent television channels from amongst a larger number of concurrent multiplexed channels concurrently made available at said receiving interface, the output of the first terminal being arranged to output the video stream of a first one of the two television channels to the screen of the first terminal, and the controller on the second terminal being configured to receive the video stream of the second of the two television channels via said wireless connection and to output the video of the second television channel to the screen of the second terminal in parallel with the output of first television channel to the screen of the first terminal.

The video stream of the selected television channel may be received via said wireless connection in encoded form, and the second terminal may comprise a decoder configured to decode the video stream of the selected television channel for output to the screen of the second terminal.

The signal processing module may further comprises a first security module configured to decrypt the selected television channel from a first encryption for output to the television screen, and the security module may be further configured to re-encrypt at least the video stream of the selected television channel according to a second encryption for receipt by the second terminal over said wireless connection, the second terminal comprising a second security module configured to decrypt the video stream of the selected television channel from the second encryption for output to the screen of the second terminal.

The controller on the second terminal may be configured to select the selected television channel.

The controller may be further configured to fetch an electronic program guide from the television receiver of the first terminal and operate the electronic program guide via the screen of the second terminal.

The controller on the second terminal may be further configured to fetch a user interface from the television receiver of the first terminal and operate the user interface via the screen of the second terminal.

The controller on the second terminal may be further configured to schedule recordings of television programs on the first terminal and control playback of the recordings. The second terminal may further comprise an internet interface to an internet being a network other than said television network, and the controller may be further configured to retrieve and display media from the internet via the screen of the second terminal.

The first terminal may comprise an internet interface to an internet being a network other than said television network, and the controller on the second terminal may be further configured to retrieve media from the internet via the internet interface on the first terminal and to display the media via the screen of the second terminal. The first terminal may be one of: a television set comprising said screen, and set-top box for plugging into said television screen.

The second terminal may be a portable terminal, The second terminal may be one of a tablet and a laptop computer.

According to another aspect of the present invention, there is provided a first terminal comprising a controller configured to support relaying of the video stream of the selected television channel from the demultiplexer to the second terminal, in accordance with any of the above combinations features of said system.

According to another aspect of the present invention, there is provided a second terminal having any of the above combinations of features of the second terminal of said system. According to another aspect of the present invention, there is provided a computer program product embodied on a non-transient computer-readable medium and configured so as when executed on a processor to perform the operations of a controller having any of the above combinations of features of the controller of said system. According to another aspect of the present invention, there is provided a computer program product embodied on a non-transient computer-readable medium and configured so as when executed on a processor to perform the operations of a controller of the first terminal.

Brief Description of the Drawings

For a better understanding of the present application and to show how it may be put into effect, reference is made by way of example to the accompanying drawings in which:

Figure 1 is a schematic block diagram of a television system, Figure 2 is a schematic block diagram of another television system,

Figure 3 is a schematic block diagram of a first terminal,

Figure 4 is a schematic block diagram of a second terminal, and

Figures 5a-5i are schematic representations of a user interface on a second terminal.

Detailed Description of Preferred Embodiments

An improved television system in accordance with a preferred embodiment of the present invention is illustrated schematically in Figure 2.

As in Figure 1, the system comprises a television network 2 such as a satellite television network in which signals are broadcast wirelessly via one or more satellites, a terrestrial television network in which signals are broadcast wirelessly via one or more land-based repeater stations, or a cable television network.

The system further comprises a first terminal in the form of a set-top box 4, and a television screen 6 (or the components of the two devices 4, 6 can be combined into the same housing to form a television set, but again for illustrative purposes the following will be described by reference to an arrangement comprising a separate set-top box 4 and screen 6).

In addition, the system further comprises a second terminal 16 in the form of a portable computer, such as a laptop computer or more preferably a tablet style computer. The following may be described in terms of a tablet for illustrative purposes, but it will be appreciated that other kinds of computer could equally be used as the second terminal 16.

The second terminal 16 is a separate terminal than the first terminal 4, by which is meant that they are separate units, i.e. housed within a separate housing (casing) and having separate hardware resources such as separate power sources and separate processors, and each being capable of operating autonomously. The set-top box (STB) 4 comprises a receiving interface 3 in the form of one or more of: an input for connecting to a radio-frequency antenna for receiving signals over a terrestrial television network, an input for connecting to a satellite dish for receiving signals over a satellite television network, and/or a cable input for receiving signals over a cable television network. The set-top box 4 further comprises a demultiplexer 8 having in input operatively coupled to the interface 3.

The network interface 3 is arranged to receive multiple concurrent television channels in the sense described above in relation to Figure V, and the demultiplexer 8 is arranged to receive an indication of the selected television channel from the user and to extract the data of that television channel for signal processing and output to the television screen 6. The set-top box 4 further comprises a signal processing module 10 having an input operatively coupled to the output of the demultiplexer 8, and a television screen output port 12 such as a coaxial output, SCART or HDMI port, etc, operatively coupled to the output of the signal processing module 10. The signal processing module comprises a decoder arranged to decode the content of the selected television channel for output to the screen 6 via the output port 12, and may also comprise a security module for decrypting the selected television channel before output. Again , the signal processing module 10 is preferably implemented in the form of a portion of executable program code stored on a storage medium of the set-top box 4 and arranged for execution on a processor of the set-top box 4. However, the option of some or all of its functionality being implemented in dedicated hardware circuitry is not excluded. The demultiplexer 8 may also be implemented wholly or partially in executable code, though in the case of a tuner it may comprise at least some dedicated tuner circuitry.

In addition, the set-top box 4 comprises another wireless transceiver 14 being of a kind other than that formed by the interface 3 and demultiplexer 8, i.e. other than a television receiver for receiving signals over the television network 2. Preferably the transceiver 14 is a short range or ad-hoc wireless transceiver such wi-fi or Bluetooth transceiver, as might be used to connect to a home network or other local area network (LAN). The following may be described in terms of a wi-fi transceiver for illustrative purpose, but it will be appreciated that other kinds could be used for the additional transceiver 14.

Furthermore, the set-top box may comprise an interface to a wide area internet (inter-network) 20 such as the Internet. This interface may be via a separate modem in the set-top box 4, e.g. a wired modem connected via a telephone land line; or may be via the wireless transceiver 14 and a wireless router on the home or local area network (not shown).

Turning to the second terminal 16, this comprises a wireless transceiver 18, e.g. wi-fi or Bluetooth, to complement the wireless transceiver 14 on the first terminal 4, allowing a wireless connection to be established between the first and second terminals 4, 16. The second terminal 16 also comprises its own screen 17.

Further details of the first terminal 4, e.g. STB, are shown schematically in Figure 3.

The first terminal 4 comprises a processor (CPU) 22 in the form of one or more processing cores, and a non-transient (non-volatile) storage medium 24 such as a magnetic storage medium (hard drive) or electronic storage medium (e.g. flash memory) operatively coupled to the processor 22. The first terminal 4 may further comprises a wired modem 26, infra red (I ) receiver 28 for receiving control signals from an IR remote control unit, the screen output port 12 (or in the case of a TV set an internal connection to the screen), the wi-fi or other such local wireless transceiver 14, and the interface 3 to the TV network 2.

The storage medium 24 stores a plurality of portions of executable program code, arranged for execution on the processor 22 (and shown schematically within the processor 22 in Figure 3 to represent running on the processor). The program code may be considered to comprise an input-output (i/o) layer 30, an operating system layer 32, a middleware layer 34, and an application layer 36. The application layer 36 comprises one or more hybrid TV applications, e.g. according to the HbbTV standard, such as a TV user interface application and further applications allowing additional functionality like web access and interactive services to be accessed via the set-top box 4 and/or television 6. The middleware layer 34 comprises a first television controller application in accordance with a preferred embodiment of the present invention, the function of which will be described shortly. The i/o layer 30 comprises a plurality of signal processing algorithms and drivers allowing the applications 34, 36 to communicate with the hardware resources 3, 12, 14, 24, 26 and 26, mediated via the operating system 32. The i/o layer 30 comprises the signal processing code 10 and de-multiplexing code 8 (in embodiments in addition to demultiplexing circuitry) for receiving a television channel from the TV network 2, an IR interface driver 40 for receiving signals from the remote control unit, a TV screen driver 42 for outputting video and graphics to the TV screen 6, a storage driver 43 for communicating with the storage device 24, and a wi-fi transceiver driver and IP protocol (or such like) for communicating with the second terminal 16 via the wireless connection.

Further details of the second terminal 16, e.g. tablet, are shown schematically in Figure 4. The second terminal 16 comprises a processor (CPU) 46 in the form of one or more processing cores, and a non-transient (non-volatile) storage medium 50 such as a magnetic storage medium (hard drive) or electronic storage medium (e.g. flash memory) operatively coupled to the processor 46. The second terminal 16 may further comprises a cellular modem 48, screen 17, and the complementary wi-fi or other such local wireless transceiver 18.

The storage medium 50 stores a plurality of portions of executable program code, arranged for execution on the processor 46 (and shown schematically within the processor 462 in Figure 4 to represent running on the processor). This program code may be considered to comprise an input-output (i/o) layer 52, an operating system layer 54, and an application layer 56, 58. The application layer comprises one or more conventional applications 58 such as a web browser, games, email client etc. The application layer on the second terminal 16 also comprises a second television controller application 56 to complement the first television controller application 34 on the first terminal 4 in accordance with a preferred embodiment of the present invention, the function of which will be described shortly. The i/o layer 52 comprises a plurality of signal processing algorithms and drivers allowing the applications 56, 58 to communicate with the hardware resources 17, 18 48 and 50, mediated via the operating system 54. The i/o layer 52 comprises a screen driver 66 for outputting video and graphics to the computer screen 17, a storage driver 68 for

communicating with the storage device 50, a wi-fi transceiver driver and IP protocol (or such like) for communicating with the first terminal 4 via the wireless connection, a signal processing module 61, a cellular modem driver and protocol stack 64 for communicating with a cellular network, e.g. 3GPP network, so as to engage in calls or as an alternative route for internet access.

The middleware controller application 34 may comprise an application programming interface (API) 36 facilitating communication with the complementary second controller application 56 via the operating system 54 and/or any other relevant protocols of the second application. Similarly, the second controller application 56 may comprise and API 60 facilitating

communication via the operating system 30 and/or any other relevant protocols on the first terminal 4.

In operation, when executed on the respective processor, the television controller applications 34, 56 operate in conjunction with one another and the other appropriate components described above to perform a process in accordance with a preferred embodiment of the present invention as follows. One function of the second controller 56 is that it is operable receive a video stream (and preferably also the audio stream(s) and any other associated data stream) of a television channel that has been demultiplexed by the demultiplexer 8 on the first terminal 4, e.g. by tuning to the required frequency of the television channel by the tuner. This is achieved by relaying the television channel including its respective video stream via the wireless connection established between the wi-fi transceivers 14 and 18 or other such short-range wireless transceivers, under control of the controller applications 34, 56.

Hence even though the second terminal 16 is not equipped with a TV tuner it is still able to play out the received video stream of a selected television channel.

The video is relayed live from the first terminal to the second terminal 16, i.e. dynamically in real-time, so that the current program of the television channel in question is being streamed from the first terminal 4 to the second terminal 16 and played out from the screen 17 of the second terminal 16 at the same time as it is being received at the receiver 3, 8 of the first terminal (allowing for a small lag between the two). There is no need to download and store the video at the first terminal.

As the local wireless connection 14, 18 (e.g. wi-fi or Bluetooth) between the first and second terminals 4, 16 is likely not to support a bandwidth high enough to relay raw uncompressed data, at least the video stream of the relayed television channel (and optionally also the audio and any associated data stream) is preferably relayed before it is decoded, i.e. the signal processing means 10 on the first terminal 4 does not decode a television channel that is being relayed to the second terminal 16. Instead the second terminal 16 comprises its own signal processing means 61 comprising its own decoder, which is arranged to decompress the video stream (and optionally audio and/or data) of the relayed television channel.

However, the signal processing module 10 may be configured to reformat the data of the relayed television channel to some extent, e.g. to repackage into a different packet format. Furthermore, the signal processing module 10 may comprise a security module configured to decrypt the television channel, including its respective video, from a first encryption standard used to broadcast over the television network 2; and then re-encrypt the television channel, again including at least the video, according to a second encryption standard appropriate for transmission over the wireless connection 14, 18 between the first and second terminals 4, 16. The signal processing module 61 on the second terminal then comprises its own decryption module configured to decrypt the video and any other media of the relayed television channel from the second encryption standard into clear form for output to its screen 17. This re- encryption process is particularly useful as television network operators are unlikely to allow unencrypted content to be transmitted via the wireless connection 14, 18, but on the other hand the encryption standard used over the TV network 2 may not be one that is convenient to decode at the second terminal. Once the television channel including the respective video stream has begun streaming to the second terminal 4 via the wireless connection 14,18, there is no need for the first terminal 4 to continue playing out the same television channel via its own television screen 6, In one embodiment, the demultiplexer 8 may be operable to demultiplex two television channels from amongst an even greater number broadcast to the interface 3. In this case a first one of the television channels, including its video stream, may be played out from the first terminal 4 using the output port 12 and television screen 6; whilst simultaneously the second of the two television channels, including its respective second video stream, may be played out using the local wireless connection 14, 18 and screen 17 of the second terminal. Alternatively the television screen 6 could just go blank or display a placeholder message.

Preferably the switching of the playout from the first terminal 4 to the second terminal 16 (and back again if desired) is controlled by the second controller application 56 acting as master, such that the first controller application 34 is a slave to the second controller application 56. Preferably the second controller application 56 is also able to control the selection of which channel is demultiplexed and relayed. The necessary control signalling between the controller applications 34, 56 is achieved via the APIs 38, 60. The first controller application 34, upon receiving instructions from the second controller application 56, may then in turn issue instructions to the hybrid TV application layer 36, e.g. to control the TV user interface (Ul) application to stop displaying the relayed television channel or to otherwise control the Ul of the STB and TV 4, 6 (such as to display a message). In response to instructions from the second controller application 56, the first controller application 34 may also issue requests to its operating system 32 requesting access to underlying driver and hardware resources 3, 6, 8, 10, 12, 14, 24, 26, 40, 42, 43 and/or 44; particularly so as to request access to the demultiplexer 8, signal processing module 10 and/or local wireless transceiver 14 to achieve the second controller application's instructions to demultiplex and relay the video stream of the required television channel (and any associated audio, data, EPG, Ul etc.); and/or to enact the necessary re-formatting and/or re-encryption of the relayed television channel. In the case where two television channels are played out from the two screens 6 and 17 in parallel, both may be under control of the second controller application 56, or alternatively the first television channel may be selected via controls of the first terminal 4 while only the second television program is selected via the second terminal 16. The selection as to whether to play two streams in parallel may also be under control of the second controller application 56.

In further embodiments, the second controller application 56 is also configured to be able to access other functions of the first terminal 4, e.g. to retrieve via the demultiplexer 8 an electronic program guide (EPG) multiplexed amongst the broadcast channels, and/or to fetch and mimic the user interface of the first terminal 4 on the screen 17 of the second terminal 16. The second controller application 56 may also be configured to obtain internet access, e.g. via the first terminal 4 via wired modem 26; and /or its own internet access via wi-fi transceiver 18 or cellular modem 48, The functionality is based around the idea of a controller application running on a second screen such as a tablet. It can be used whilst the user is watching TV as an extension to the onscreen user interface and also as a remote access device whilst the user is away from their house.

The use cases given below illustrate ways that a second screen could be used to interest the viewer, thus differentiating the solution offerings and potentially give new modes of access for the broadcaster. The main use cases cover examples of the more complex or particular interesting use cases and are not meant to reflect the full range of functionality that such an application could be potentially have.

The descriptions below refer to a tablet and a tablet application as the use cases and requirements are not dependant on the platform on which the solutions will run and versions of the application can be provided to run on multiple different operating systems.

The application may for example be written in HTML/JS and run on the built-in Mobile Safari. It may be wrapped in a native code wrapper to allow it to be distributed via an online store for simplicity.

Visual elements (such as the EPG) will preferably be styled to be recognisably from the same brand as the STB EPG and therefore may reuse some of the graphical elements. The design and the layout of the EPG will be similar to the STB EPG but will be first and foremost designed to be a good tablet implementation of an EPG. For example use of swipe to scroll, pop-ups to show more info, finger size buttons, full screen display, etc.

Here is a summary of the preferred components of the system. The tablet application (second controller application 56) running on the tablet features the following screens:

- EPG

STB recording list browser (completed and scheduled)

- Video playback screen for streamed video

Suitable Platform

The following extensions may be provided:

Export information to tablet such as channel list, programme information, recording list - Tablet control of channel change, recording scheduling, recording playback, catch-up video playback

Feedback on result of control actions

A web server to stream media from the STB to the tablet.

A way to allow photos and other media to be pushed to the STB

A new application may be provided that can be triggered by a playback request from the tablet and can do the following with the data received:

Receive and display photo and photo slideshow

Playback audio stream

- Playback video stream

The example use cases are now provided. All these use cases relate to when the user is in their home network with the STB to be controlled. Extra considerations to implement remote access are given later.

Use case 1: EPG on different devices.

The user can display an EPG on the tablet that allows them to see the channels and

programmes available to them. The channel line up should match what is displayed on the TV including options to show favourite lists set up on the TV. The design of the EPG should match that displayed on the TV in looks/branding and to an extent in feel as well - whilst allowing for difference in usage on a tablet as opposed to a TV. The EPG should go back in time as well as forwards

The user can perform the following actions:

Display information on any programme (maybe including a picture)

Schedule a recording of a programme

Change the channel on the TV

- For a programme in the past then play the programme on the TV as VoD (if available)

Preferred implementation:

EPG implementation in the tablet app

Fetch the channel list from the STB, including favourite lists

- Fetch programme information from the STB , maybe on demand, but preferably caching the entire 7 days.

Control STB to change channel, schedule recording, play catch-up VOD stream

Get feedback from STB on control response (e.g. conflict management) Use case 2: View content on tablet

The user can display a list of videos stored on the STB such as recordings made. The user can: Display information about the video

Play the video on the TV

- Stream the video from the STB to tablet

Preferred implementation:

Fetch video list from STB

Control STB to start playback of video Stream video from STB to tablet

Use case 3: Other media The user can use the TV as an extended display device for their tablet. In the home network the user can:

- Choose a photo from the tablet photo gallery and cause it to be displayed on the TV Choose a selection of photos from the tablet photo gallery and display them as a slideshow on the TV

Choose music or video from the tablet storage and cause it to be played back on the TV.

Preferred implementation:

- Send data from tablet either by uploading or by sending URL(s) and using a web server on the tablet. Uploading is sufficient for photos, web server would be better for music/video

- Application suite to display the media received. Other use cases

Here are other use cases or variants, listed separately as they are not covered explicitly above. A Ul layout might consider incorporating mention of these in menus, tool bars etc.

Search the EPG (and recordings) for programmes matching some search text

Search the internet for related content

- Stream the currently playing channel to the tablet.

Stream catch-up content to the tablet

View, control playback and stream to tablet downloaded content as well as recordings (when downloaded content is supported)

Remote operation A variant of use case 1 would have the user able to perform a sub set of the operations whilst outside the home network, e.g. over 3G or at a WiFi hotspot. In these cases requests to the STB (e.g. schedule recording) would be done via some kind proxy server that would store and forward requests and responses. Whilst the basic functionality required here is simple there are numerous issues around privacy, identification and security that would need to be examined for a production system. Other changes in this case could be:

Ideally need to acquire programme information directly from a remote server so that it is always available even when the user hasn't revisited the home network and synced with the STB for more than a week.

External VOD catalogue - the user can display on the tablet the web site of a VoD provider such as Lovefilm or Netflix. The user can:

- Play a video from the provider on the TV

- Start a download from the provider to the STB for later viewing

Other media - 3 box model - As well as taking media from the local device the user could use the tablet as a controller to take media (photos, music, videos) from a PC server and cause it to be played on the TV. This is a potentially powerful demo that has been an option for many companies for several years but so far no one has built a Ul that is easy to use. The user can: connect to a server, choose some media and ask for it to be rendered on the TV,

Preferred implementation:

- UPnP AV controller in tablet, UPnP AV renderer

- Application suite app to render the received media Further notes on preferred implementation

The way features are used should match the STB where practical, e.g. terminology, base features, theme, etc.

Tablet application: The app should start up into the Home screen, with buttons to link to other screens.

Home screen

- Show information on what is currently being watched or playing on the TV

Trickplay controls for TV including a scrub bar

Buttons to switch to EPG or recording screens

EPG Screen

- Grid view EPG display

Scroll up and down to display more channels

Scroll left and right to display earlier/later programmes (7 days each way)

Select programme to display more info and options

Choose which channel list to view (e.g. favourites)

- Highlight channel and programme currently being viewed

Highlight channels and programmes currently being recorded

- Trick-play current channel/recording

Programme options popup:

- This could be a popup or an info panel relating to the selected item.

Schedule a single recording

Schedule a series recording

Schedule a reminder on the TV

Change to this channel on the TV - For a programme in the past then play on the TV as VoD (if available)

- Other programmes (other showing/episodes, recommendations, etc)

Explore programme (episode guide, external web sites, etc)

View channel on tablet

- For a programme in the past then play on the tablet as VoD (if available)

- Schedule a reminder on the tablet (inside the app or via the calendar)

Rate this programme

Post to twitter/facebook/email/screentribe/... Recordings screen

Display list of recordings with similar filtering and sorting options as STB

Display list of scheduled recordings

Drag and drop recordings to create folders

Delete recording iPad style

Recording options popup

As with programme info this could be a popup or an info panel relating to the selected item.

Play recording on TV

- Stream recording to tablet

Edit recording properties

Video playback screen - this is launched from one of the "play on tablet" menu items. Closing it takes you back to the previous screen.

- Show/hide overlay

Overlay shows trickplay controls, metadata, scrub bar

Pause, play, rewind, fast forward

Stop playback

Close button Media selection screen - this screen is not needed if an AirPlay compatible solution is used as the media will be pushed from the existing iPad applications.

Choose one or more photos from the tablet photo library

- Push them to the TV to be displayed as a slideshow

Choose an audio or video file to play on TV

Communication use cases: the following require some communication between the tablet and the STB.

On launch

Fetch the channel list from the STB, including favourite lists, metadata and icons Fetch programme information from the STB, maybe on demand, but preferably caching the entire 14 days (7 days each way)

Schedule single or series recording

Send record message to STB

Display response or conflict message

Resolve conflict or cancel

Change channel

Send change channel message to STB

Display response or conflict message

Resolve conflict or cancel

Play recording on TV

Send playback request to STB

Display response Stop recording playback on TV

Send stop playback message to STB.

Trickplay

- Send trick play message to STB - Pause, play, rewind, fast forward (live or recording playback), jump to position

Update local trick-play indicators with state

Stream data from STB

Request streaming URI for channel or recording

Push media to the STB

Send photos to the STB to display as a slideshow. This could be done by emulating an AirPlay server or by a custom protocol

If using AirPlay then an mDNS service is needed on the STB that advertises it as supporting AirPlay

Notifications

- The app needs to be notified in any of the following cases so it can update its display.

If any channel list is updated

If recording or scheduled recording changes state (including new and delete)

If current channel changes

Some of the above use case features are illustrated in the schematic mock-up user interface of Figures 5a to 5i, representing schematically the user interface as would be seen and controlled on the screen 17 of the second terminal 16 via the second controller application 56.

Figure 5a: "My TV" (Dashboard)

Figure 5b: EPG Figure 5c: Current Programme Info

Figure 5d: Future Programme Info

Figure 5e: Scheduled Recording Info EPG

Figure 5f: Recordings

Figure 5g: Scheduled Recording Info

Figure 5h: Recorded Programme Info

Figure 5i: Play/Resume

It will be appreciated that the above embodiments have been described only by way of example. Other variants may become apparent to a person skilled in the art given the disclosure herein. The scope of the present invention is not limited by the described embodiments but only by the appendant claims.