An interactive television system where interactive information is inserted in the vertical blanking interval of a standard television signal. The signal is received and decoded by a settop decoder which sends the decoded signal via an infrared signal to a handheld device. The viewer using the handheld device can interact with a game, sports, or educational event or other presentation on the television. The system includes a proprietary high level command language and programmer (PIU) tables which are maintained in the memory of the handheld device. The PIU tables store the transactions of the various events presented on the television. The transactions are sent from the insertion system to the decoder throughout the broadcast of the television program. Thus, for a sports event with interleaved commercials, one or more of the PIU tables would be used to store a collection of transactions used for the main event and one or more additional PIU tables are used for storing transactions for each of the interleaved commercials. This system allows a viewer to enter and exit any event at any time without having to wait for information to be downloaded and without losing any scores. Further, the system allows the user to change from event to event such as, for example, by tuning to different stations and be able to immediately interact and have responses scored and stored.

Transaction based interactive television system

A method for decoding auxiliary data from media signals in multimedia content decodes watermarks from different media signals and uses the watermarks to control processing of the multimedia content. A copy control method decodes a watermark from one of the media signals in multimedia content, and uses the watermark to control processing of the multimedia content. Another method uses a watermark decoded from a first media signal to decode a second media signal. Yet another method uses a watermark decoded from a media signal to decode metadata associated with the media signal. Finally, another method forms a key for decoding data from at least first and second watermarks extracted from first and second media signals.

Integrating digital watermarks in multimedia content

A system for providing security on an interactive television system (see the figure). Two sets of interactive data, with time stamps (22), are separately sent (24, 26) to a remote location (28, 32, 34). At the remote location (28, 32, 34), the time stamps are checked against a remote clock, a time difference being noted for both sets of data. The two differences are compared to determine if one set of data has been delayed as compared to the other. Non-delayed data can be used to update a game score for an interactive game. After the game is completed, the remote clock is compared with a central clock. The difference between the two clocks is compared to the time difference for non-delayed data to determine whether the entire aggregate of interactive data was delayed.

Interactive television security through transaction time stamping

Data which is transmitted over the internet or other transmission networks is first divided up into individual information packets, transmitted and then reassembled into useful data after reception. Parity packets are included in with the information packets in the transmission of data in order to enable the regeneration of any information packets which were lost or damaged during transmission. The grouping of information packets and parity packets derived therefrom is termed a chunk. Chunk arrangements to recover from all cases of single and double lost packets are disclosed. Bursts of lost packets are recovered by interleaving the transmission of packets from different chunks. If the recovery is not successful then retransmission occurs in a manner similar to TCP.

System for recovering lost information in a data stream

A distributed database system having a central station (11) for distributing data to a plurality of receiver stations (13). The central station (11) includes a server (17) for extracting data from a database stored in its data store and generating a sequential data stream for distribution, and a transmitter (21) for encoding and transmitting the data stream. Each receiver station (13) includes a decoder (25) for decoding a received data stream so as to reconstitute the database data, a keypad (31) for a user to selectively key in user commands, a receiver processor (27) for constituting a database based on the user commands, memory (29) for storing the constituted database, and communication means (33) for communicating selected data to the user.

Distributed database system and database receiver therefor

An encoding technique for data that enables the data to be reliably transmitted via television signals, even when impulse noise may be present, uses a two-fold approach for forward error correction. As a first step, the data is assembled into blocks of suitable length and each block is encoded with an error correcting code to enable individual bit errors to be identified and corrected at the receiving end. In addition, the blocks of data are interleaved over several different lines of information. Each line of information is transmitted during the vertical blanking interval in a respective field of a video signal. At the receiving end, the individual lines of data are reassembled into the blocks of information. If impulse noise or other disruptions cause one of the lines to be lost, the result at the receiving end would only be the loss of one bit of data in each block. The error correcting code with which each block is encoded enables this individual bit error to be identified and corrected.

Forward error correction of data transmitted via television signals

This article discusses the PBS VBI data delivery system, a point-to-multipoint data link using the vertical blanking interval {VBI) of the public television signal. Development of the system for PBS Enterprises, a subsidiary of PBS, has taken place over the past several years, with emphasis on quality performance. Since broadcast television has traditionally been a harsh environment for VBI data systems, PBS has developed and implemented its own unique error-correction techniques. The methodology used to determine the error-correction parameters is discussed. Major components of the system, including the data inserter at the PBS uplink, the data bridge at a typical PBS member station, and the VBI Data Receiver (VDR TM ) at the end user's site, are described. A summary of the system performance is also presented.

Aderemi A. Adeyeye

Papers

Forward error correction of data transmitted via television signals

Development and Performance of the PBS VBI Data Delivery System