Abstract: A captioning system is provided for providing captions for audio and/or video presentations. The captioning system can be used to provide text captions or audio descriptions of a video presentation. A user device is provided for the captioning system having a receiver operable to receive the captions together with synchronization information and a caption output circuit which is operable to output the captions at the appropriate timings defined by the synchronization information. The user device is preferably a portable hand-held device such as a mobile telephone, PDA or the like.

Abstract: There is described a communication system in which data is received by and/or transmitted to a telecommunications apparatus using an acoustic data channel. In embodiments, the data is encoded within the audio track of a media broadcast or other public broadcast. The invention has particular, but not exclusive, relevance to a cellular communication system. There are also described acoustic position detection systems for determining the position of a telecommunications apparatus.

Abstract: A bookmarking system is described for allowing users to bookmark audio and video content for sharing with other users. The system allows the bookmark to be generated with minimal user involvement, making the process as easy to use as the bookmarking of websites on a computer device. A disambiguation server is provided to disambiguate the content to be book-marked. The disambiguation server uses information from various sources to provide a number of candidates for selection by the user. Historical data and the bookmarks of other users can also be used to aid the disambiguation process.

Abstract: A cellular telephone is provided for recovering hidden data that is embedded within an input acoustic signal. The telephone passes the acoustic signal through an audio coder of the telephone and then processes the compressed audio generated by the audio coder, to recover the hidden data. A similar telephone is also provided for identifying the audio signal from the compressed output of the audio coder. Various coding techniques are also described for hiding the data within the audio.

Abstract: There is described a communication system in which data is received by and/or transmitted to a telecommunications apparatus using an acoustic data channel. In embodiments, the data is encoded within the audio track of a media broadcast or other public broadcast. The invention has particular, but not exclusive, relevance to a cellular communication system. There are also described acoustic position detection systems for determining the position of a telecommunications apparatus.

Abstract: There is described a communication system in which data is received by and/or transmitted to a telecommunications apparatus using an acoustic data channel. In embodiments, the data is encoded within the audio track of a media broadcast or other public broadcast. The invention has particular, but not exclusive, relevance to a cellular communication system. There are also described acoustic position detection systems for determining the position of a telecommunications apparatus.

Abstract: There is described a number of encoders for encoding a data signal within an audio signal. In some of the encoders, the audio signal is separated into a tonal part and a residual part, and the data signal is shaped based on the residual part. In other encoders, the data signal is separated into a tonal part and a residual part, and the data signal is combined with the audio signal independence upon the residual part. In other encoders, the rate at which the data is encoded within the audio signal is varied in dependence upon the audio signal. There are also described various decoders associated with the described encoders.

Abstract: There is described a communication system in which data is received by and/or transmitted to a telecomunications apparatus using an acoustic data channel. In embodiments, The data is encoded within the audio track of a media broadcast or other public broadcast. The invention has particular, but not exclusive, relevance to a cellular communication system. There are also described acoustic position detection systems for determining the position of a telecomunications apparatus.