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AT&T's Error Resilient Video Transmission Technique (RFC2448)

IP.com Disclosure Number: IPCOM000004280D
Original Publication Date: 1998-Nov-01
Included in the Prior Art Database: 2005-May-22
Document File: 8 page(s) / 15K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

M. Civanlar: AUTHOR [+3]

Abstract

This document describes a set of techniques for packet loss resilient transmission of compressed video bitstreams based on reliable delivery of their vital information-carrying segments. The described techniques can be used over packet networks without packet prioritization. These techniques are related to AT&T/Lucent patents [1, 2].

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 19% of the total text.

Network Working Group                                        M. Civanlar
Request for Comments: 2448                                       G. Cash
Category: Informational                                       B. Haskell
                                                      AT&T Labs-Research
                                                           November 1998


          AT&T's Error Resilient Video Transmission Technique

Status of this Memo

   This memo provides information for the Internet community.  It does
   not specify an Internet standard of any kind.  Distribution of this
   memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (1998).  All Rights Reserved.

Abstract

   This document describes a set of techniques for packet loss resilient
   transmission of compressed video bitstreams based on reliable
   delivery of their vital information-carrying segments. The described
   techniques can be used over packet networks without packet
   prioritization. These techniques are related to AT&T/Lucent patents
   [1, 2].

1. Introduction

   It is well known that every bit in a compressed video bitstream is
   not equal. Some bits belong to segments defining vital information
   such as picture types, quantization values, parameter ranges, average
   intensity values for image blocks, etc. When transporting compressed
   video bitstreams over packet networks, packet losses from such
   segments cause a much longer lasting and severe degradation on the
   output of a decoder than that caused by packet losses from other
   segments. We will call the vital information-carrying segments "High
   Priority (HP)" segments. The rest of the bitstream consists of "Low
   Priority (LP)" segments. Clearly, the video outputs resulting from
   transport techniques that protect the HP segments against packet
   losses are more resilient to packet losses in general.

   Protection of the HP segments can be accomplished in many ways. These
   include:

      - redundant transmission of the HP segments as described
        in [3] for MPEG RTP payloads

Civanlar, et. al.            Informational                      [Page 1]
RFC 2448                AT&T's Error Resilient             November 1998


      - using forward error correction (FEC) techniques
      - transmitting HP segments over reserved channels or using
        differentiated services.

   Both redundant transmission and FEC techniques increase the bandwidth
   needed to transmit the compressed video bitstream. FEC techniques
   increase the effectiveness of this additional bandwidth for packet
   loss protec...