KR100637006B1 - Interactive television transmission system - Google Patents

Abstract

The interactive television transmission system comprises a television transmitter 1 and at least one television receiver 3. In addition to the television program TV, the transmitter transmits an operation signal OP which defines the actions taken by the receiver upon user participation. According to the invention, the transmitter comprises means 15 for transmitting an indication signal ID indicating, for example, that the television program is an interactive program in a teletext packet 8/30. The receiver is arranged to receive and detect the indication signal and generates a recognizable indication (OSD) in response to the detection to inform the user about the program type and activate the associated processing circuit 36.

Description

Interactive television transmission system

The present invention relates to an interactive television transmission system comprising a television transmitter and at least one television receiver. The transmitter comprises means for transmitting television signals and means for transmitting an operation signal for an interactive mode of operation of the television receiver. The receiver includes means for receiving and reproducing television signals. The invention also relates to a transmitter and a receiver for such a system.

The known interactive television transmission system mentioned at the outset is disclosed in international patent application WO-A 93/10605. In this prior art system, the user can interact with the television program. To this end, an operating signal defining actions to be taken by the receiver upon user participation is transmitted in the vertical blanking interval of the television signal. The prior art receiver comprises a set top box for this, i.e. a dedicated processing circuit for processing the operation signals and enabling interactive participation. The processing circuitry also implicitly informs the user that the interactive television program is being broadcast.

1 illustrates an interactive television transmission system in accordance with the present invention.

FIG. 2 shows a part of a television signal waveform transmitted by the transmitter shown in FIG. 1; FIG.

3 shows a flowchart of a control program executed by the microprocessor shown in FIG.

It is an object of the present invention to further improve an interactive television transmission system.

To this end, the system transmits an indication signal indicating that an operating signal is transmitted, and the receiver includes means for receiving and detecting the indication signal and generates a perceptible indication in response to the detection. Characterized in that. In this way, the interactive television program broadcast is displayed to the user without the operation signals being processed. Another advantage of the present invention is that if the user does not want to participate in the interactive programs, there is no need to process the operation signal. In particular, the processing circuit can be used for other purposes, inter alia, for the advanced capture of teletext pages transmitted together in the vertical blanking interval of the television signal. The invention also provides for the development and production of television receivers that, if the user wants to participate in interactive television programs, the producer detects an indication signal without processing the operation signals and displays a message to the user to promote the upgrade of the receiver. Make it possible.

In an embodiment of the invention, the indication signal is transmitted repeatedly at regular time intervals, for example once per second. This achieves a significant reduction in transmission capacity, and nevertheless, the user can talk without regard to whether the mode of operation is enabled while the user watches a certain channel or whether the mode of operation is already available on the channel just selected by the user. Appropriate and timely notification of the availability of the type mode of operation. In a preferred embodiment, the indication signal is a predetermined bit pattern of a predetermined teletext packet, for example a packet 8/30 of the World System Teletext standard.

1 illustrates an interactive television transmission system in accordance with the present invention. The system comprises a television transmitter 1, a broadcast channel 2, an interactive television receiver 3 and a backward channel 4. The broadcast channel 2 may be a storage medium such as a magnetic tape or an optical disk on which a television program is stored. The reverse channel is here assumed to be a public switched telephone network (PSTN).

The transmitter 1 comprises here a television program signal source, represented by a television camera 11 which generates a conventional television signal TV. The transmitter further comprises a teletext generator 12 for generating a teletext signal TX in a conventional way, ie, using lines in the vertical blanking interval of the television signal. The television program is assumed to be a quiz show in which the public can participate by sending an answer to a question. To this end, the computer 13 generates operational signals OP in the form of data sequences that define the actions taken by the receivers in response to participation by the user. For example, the data sequence defines a telephone number to be called by the receiver, identifies how the user's response is encoded in the telephone call, and specifies a time interval during which responses can be given. The operation signals are transmitted in the same way as the teletext of the vertical blanking interval of the television signal. To receive telephone calls from the public, computer system 13 is connected to public access telephone network 4 via telephone connection 14. According to the invention, the transmitter further comprises means 15 for generating an indication signal ID indicating that the interactive television program is being broadcast. The means 15 are controlled by the computer system 13 via a connection 16. The television signal TV, the teletext signal TX, the display signal ID and the operation signal OP are coupled to the coupling end 17 and collectively on the modulator 18 for RF transmission through the antenna 20. Is applied.

2 shows a portion of a television signal waveform transmitted by a transmitter. Reference numeral 25 denotes the vertical blanking interval of the television signal, which in a 625-line system includes 6-22 lines in one field and 318-335 lines in the other field. In this example, reference numeral 26 denotes a teletext data packet. Reference numeral 27 denotes an operation signal in the form of a data sequence, which is transmitted only when the television program is an interactive program. Reference numeral 28 denotes one of the lines of the active video interval carrying the conventional analog video signal.

Each teletext packet 26 contains a 3-bit magazine number and a 5-bit column number. Packets with column numbers in the range 0-24 are defined as display columns. Teletext data packets with magazine number 8 and column number 30 are transmitted once per second. These packets 8/30 are generally referred to as broadcast service data packets. This includes, among others, the initial teletext page to be captured, the current time, network identification, program label, and the like. Some bits of the broadcast service data packet are not defined yet. According to the invention, one or more of these bits (indicated 29 in FIG. 2) are used to indicate that the operating signals 27 are transmitted, ie that the television program is an interactive program.

Referring to FIG. 1, the transmitted signal is received by the receiver 3 via the antenna 21 and demodulated by the tuner 30. The tuner applies a demodulated baseband signal to conventional audio and video processing circuitry 31 to reproduce a TV program through loudspeaker 32 and display screen 33. The baseband signal is also applied to a data slicer 34 which extracts data inserted in the vertical blanking interval of the signal, which is stored in the buffer portion of the memory 35. The memory 35 is connected to the microprocessor 36 which receives user commands from the (remote) control unit 37 and is also connected to the telephone network 4 via the modem 39. The memory 35 also includes a display unit. The data stored in this display by the microprocessor 36 is converted into an on-screen display signal OSD for display on the screen 33. It can be appreciated that the microprocessor can generate a signal that can also be heard in this manner and apply it to the loudspeaker 32.

The operation of the receiver 3 will now be described with reference to FIG. 3, which shows a flow chart of the control program executed by the microprocessor 36. As already mentioned, the data packets (ie, packets 26 and 27 shown in FIG. 2) transmitted in the lines of the vertical blanking interval are stored in the buffer portion of the memory 35. These are processed by the microprocessor during the active video interval.

In the initial stage 300 of the control program, the interactive TV flag ITV is assigned an initial value of zero. In step 301, the microprocessor waits for the end of the vertical blanking interval. In step 302, a packet received in the vertical blanking interval is read from the buffer portion of the memory 35. In step 303, it is determined whether the packet is a teletext broadcast service packet 8/30. If it is a packet 8/30, it is checked in step 304 whether the indication signal ID is transmitted by the transmitter (see FIG. 1). This step includes determining the value of the particular bit or multi-bit code 29 shown in FIG. If the display signal ID is detected, the flag ITV is assigned a value 1 in step 305, which initially stores information that the current television program is an interactive program. In step 306, an on-screen display signal (OSD; see FIG. 1) is generated and notifies the user that the user can participate in the program if desired. If the indication signal ID has not been detected in packet 8/30, the flag ITV is reset (step 307) and the OSD signal is not generated or switched off (step 308).

After packet processing, it is checked in step 309 whether all packets received in the buffer portion of the memory have been processed. If all packets are not processed, the control program returns to step 302 to process the next packet. On the other hand, if all packets have been processed, the program returns to step 301 to wait for the end of the next vertical blanking interval and process the next burst of data.

If the data packet is not a broadcast service packet, the program determines if the television program is an interactive program by testing a flag (ITV) at step 310. If the program is not interactive (ITV = 0), the microprocessor executes the teletext operation program 311. By this program, the teletext data packet TX (26 in Fig. 2) is captured and decoded to store a plurality of teletext pages in memory for immediate access in the teletext mode of operation. Since the operation signals OP 27 in Fig. 2 are not transmitted, they do not need to be processed in this case.

If the program is interactive (ITV = 1), then at step 312 it is determined whether the user is actively participating in the program. Step 312 includes checking whether the key 370 (see FIG. 1) of the receiver is pressed or already pressed. If the program is interactive but the user does not participate, the aforementioned teletext action program 311 is executed. Even if the operation signals OP are available, this case does not need to be processed. If the program is interactive and the user participates, the interactive mode of operation is activated. In this mode of operation, operational signals OP (27 in FIG. 2) are processed by the microprocessor in accordance with program 313. Optionally, checking 312 whether the user actually participates can be omitted. This progressively allows the receiver to process the operating signals OP, thus predicting the user's participation in later steps.

As can be readily appreciated from the above technique, processing of operating signals (which can be a complex and time-consuming operation) is performed only when the TV program is actually interactive. Processing is not required for generation of the OSD signal. Thus, as long as the program is not interactive, the associated processing circuitry (in this example, the microprocessor) can alleviate the processing of the operating signals and perform other tasks instead.

In summary, an interactive television transmission system comprising a television transmitter 1 and at least one television receiver 3 is disclosed. In addition to the television program TV, the transmitter transmits operational signals OP which define the actions taken by the receiver upon user participation. According to the invention, the transmitter comprises means 15 for transmitting an indication signal ID indicating, for example, that the television program is an interactive program in a teletext packet 8/30. The receiver is arranged to receive and detect the indication signal, generate a recognizable indication (OSD) in response to the detection to inform the user about the type of program and activate the associated processing circuit 36. .

Claims (14)

An interactive television transmission system comprising a television transmitter (1) and at least one television receiver (3), The transmitter, Means 11 for transmitting television signals 28, Means (13) for transmitting operational signals (27) defining actions to be taken by the television receiver in an interactive mode of operation of the television receiver, The receiver, Means (31) for receiving and reproducing the television signals; Means for receiving (35) and processing (36) the operational signals, The transmitter comprises means 15 for transmitting an indication signal 29 indicating whether the operation signals are transmitted, the receiver receiving 34 and detecting 36 the indication signal and the operation signals being transmitted. And means (38) for generating (38) a perceptible indication (OSD) in response to said detection. The method of claim 1, And the indication signal is repeatedly transmitted at regular time intervals. The method of claim 2, And the indication signal is a predetermined bit pattern of a predetermined teletext packet. In the interactive television transmitter 1 Means 11 for transmitting television signals 28, Means 13 for transmitting operational signals 27 defining actions to be taken by the television receiver in the interactive mode of operation of the television receiver 3, and Means (15) for transmitting an indication signal (29) indicating whether the operational signals are transmitted. The method of claim 4, wherein And the indication signal is transmitted repeatedly at regular time intervals. The method of claim 5, And the indication signal is a predetermined bit pattern of a predetermined teletext packet. As the television receiver 3, Means (31) for receiving and reproducing television signals transmitted by a transmitter, Means for receiving 35 and processing 36 operational signals 27 sent by the transmitter, the operational signals defining actions to be taken by the television receiver in an interactive mode of operation of the television receiver, The receiving and processing means, and Receive 35 and detect 36 an indication signal 29 indicative of whether the operation signals are transmitted and generate 38 a recognizable indication (OSD) in response to the detection indicating that the operation signals are transmitted. And means for doing so. The method of claim 7, wherein Processing means for processing the operation signals in the interactive mode of operation, And the receiver comprises user-operable means for activating the processing means when the indication signal is detected. The method of claim 7, wherein And the indication signal is repeatedly received at regular time intervals. The method of claim 9, And the indication signal is a predetermined bit pattern of a predetermined teletext packet. CLAIMS 1. A method of transmitting television signals to at least one television receiver, comprising: transmitting (13) operational signals 27 that define actions to be taken by the television receiver in an interactive mode of operation of the television receiver, and Transmitting (15) an indication signal indicative of whether the operation signals are being transmitted. A method of receiving television signals from an interactive television transmitter, the method comprising: receiving (35) and processing (36) operational signals (27) transmitted by the transmitter, wherein the operational signals are interactive mode of operation of the receiver The receiving and processing step of defining the actions to be taken by the television receiver at, and Receiving and detecting 304 an indication signal indicative of whether the operation signals are transmitted, and generating 306 a perceptible indication in response to the detection indicating that the operation signals are transmitted. , A method for receiving television signals. In a television signal comprising operational signals 27 defining actions to be taken by the television receiver in an interactive mode of operation of the television receiver, And a display signal (29) indicating whether the operation signals are transmitted. The storage medium according to claim 13, wherein the television signal is stored.