Patent ID: 7693188

Claim:
A method, operating in electronic remultiplexing apparatus, of dynamically remultiplexing at least one transport stream of transport packets, each transport packet having the same length, each transport packet having a payload carrying information for only one specific stream, such as an elementary stream or systems information, such as program specific information, the method comprising the steps of: (a) extracting selected transport packets from at least one received transport stream, (b) generating new transport packets containing new systems information not already carried in the received at least one transport stream, (c) assembling at least one of the extracted transport packets and the new transport packets containing systems information into an output transport stream according to a first specification of streams to be carried in the output transport stream, wherein each stream specified in the first specification of streams includes information of a respective program, and outputting the output transport stream, (d) receiving a request to effectuate a second specification of streams different from the first specification for the output transport stream, wherein each stream specified in the second specification of streams includes information of a respective program, the second specification indicating a change in the streams carried in the output transport stream relative to the first specification, (e) determining whether or not the second specification is valid to produce a valid output transport stream, (f) if it is determined that the second specification is valid to produce a valid transport stream then: (1) selectively changing the particular transport packets that are extracted, if necessary according to the second specification, (2) selectively changing the generation of new transport packets, if necessary to effectuate the second specification, and (3) selectively changing the assembly of the extracted transport packets and the new transport packets from the assembly according to the first specification to an assembly according to the second specification, at specific times so as to ensure that contiguity of the output transport stream is seamlessly maintained while changing from extraction, generation and assembly according to the first specification to extraction, generation and assembly according to the second specification, and so as to ensure that the systems information carried in the output transport stream validly references other streams carried in the output transport stream while extracting, generating and assembling according to each of the first specification and the second specification.