Abstract: The invention relates to methods, devices and computer program codes for enabling simple seamless switch over between content related media streams, selecting a switching scheme and performing simplified switch over between such streams, as well as a set of media signals. The media streams (TS1, TS2, TSN) have access units (AU1, AU2, AU3), the lengths of which are made equal by adding filling packets (N). By doing this, overhead data (O1, O2, ON) related to the streams can also be made almost identical. This fact is then used for fast determination of switch over method and simplified seamless switch over between different media streams.

Abstract: Method of caching teletext page data received from an arrangement of a channel selection circuit, arranged to retrieve a signal comprising video information and embedded teletext page data and belonging to a channel selected in accordance with a user command, and a teletext retrieval circuit, arranged to extract the teletext page data embedded in the received signal. A count of elapsed time is started upon determining that a user command for a switch from a first selected channel to a second selected channel has been issued. Storage of received teletext page data in a memory unit is commenced when the count exceeds a certain time interval. The count of elapsed time is re-started from zero if it is determined that a user command to switch from the second selected channel to any other selected channel has been issued.

Abstract: Disclosed is a system for generating a content presentation signal such as an audiovisual signal. A content source (203), such as a Digital Versatile Disc (DVD) comprises a plurality of content data streams (301, 303, 305, 307). The content source (203) further comprises a virtual content stream (309) comprising content data pointers to the content data of the plurality of content data streams (301, 303, 305, 307). An apparatus (200) comprises an interface (201) for the content source and a virtual content stream processor (205) which retrieves the virtual content stream (309) through the interface (201) and stores it in memory (207). A data pointer processor (209) selects data pointers in response to a presentation criterion, such as a desired quality or data bandwidth of the interface (201). A presentation signal processor (211) generates a content presentation signal by retrieving the content data of the plurality of content data streams pointed to by the content data pointers.