Front terminal device and method of modem

Abstract

A method (200) and apparatus(100) for recovering a second transport stream included within a first transport stream and reducing timing anomaly imparted to the second transport stream within the context of a front-end device subject to random access via a data bus, illustratively a PCI bus. A first transport stream is received from a transport medium (205), the first transport stream having disposed therein packets associated with a second transport stream, the first medium tending to impart jilter to the first transport stream. Those packets associated with the second transport stream are extracted from the first transport stream (210) and adapted to reduce jitter (220, 230, 240), and launched via a second transport medium (250), the launched adapted packets forming a jitter-reduced second transport stream.

Description

Technical field [0001] The present invention relates to a two-way communication device such as a modem, and more particularly, to a modem that provides a timing error processing function suitable for application of abnormal interface timing. Background technique [0002] A modem is currently used as a separate computer peripheral device that interfaces a host device such as a personal computer (PC) with an external broadband gateway or an access network such as a cable TV or a telecommunication company. The modem can be thought of as a "front-end" device that retrieves information from the access network and provides that information to a "back-end" device such as a PC. In a typical configuration, a modem, such as a digital subscriber line (DSL) or cable modem, interfaces with the PC through an external device interconnection (PCI) slot connected to the PC. [0003] The PCI slot is typically one of many PCI slots or an interface connection sharing a common PCI bus structure. Ther...

AI Technical Summary

Problems solved by technology

[0004] In the case of MPEG audio-visual data, excessive network jitter or incorrect recovery of the 27MHz clock associated with the MPEG transport stream can cause buffer overflow, buffer underflow, unexpected color changes, and other unwanted phenomena, which will result in incorrect playback of transmitted audiovisual material

Such network jitter or incorrect clock recovery (or other timing operations) can be caused by PCI bus accesses / services

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