RTP Payload Format for JPEG-compressed Video (RFC2035)
Original Publication Date: 1996-Oct-01
Included in the Prior Art Database: 2000-Sep-13
Internet Society Requests For Comment (RFCs)
L. Berc: AUTHOR [+4]
This memo describes the RTP payload format for JPEG video streams. The packet format is optimized for real-time video streams where codec parameters change rarely from frame to frame.
Network Working Group L. Berc
Request for Comments: 2035 Digital Equipment Corporation
Category: Standards Track W. Fenner
Lawrence Berkeley Laboratory
RTP Payload Format for JPEG-compressed Video
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
This memo describes the RTP payload format for JPEG video streams.
The packet format is optimized for real-time video streams where
codec parameters change rarely from frame to frame.
This document is a product of the Audio-Video Transport working group
within the Internet Engineering Task Force. Comments are solicited
and should be addressed to the working group's mailing list at rem-
firstname.lastname@example.org and/or the author(s).
The Joint Photographic Experts Group (JPEG) standard [1,2,3] defines
a family of compression algorithms for continuous-tone, still images.
This still image compression standard can be applied to video by
compressing each frame of video as an independent still image and
transmitting them in series. Video coded in this fashion is often
We first give an overview of JPEG and then describe the specific
subset of JPEG that is supported in RTP and the mechanism by which
JPEG frames are carried as RTP payloads.
The JPEG standard defines four modes of operation: the sequential DCT
mode, the progressive DCT mode, the lossless mode, and the
hierarchical mode. Depending on the mode, the image is represented
in one or more passes. Each pass (called a frame in the JPEG
standard) is further broken down into one or more scans. Within each
scan, there are one to four components,which represent the three
components of a color signal (e.g., "red, green, and blue", or a
luminance signal and two chromanince signals). These components can
be encoded as separate scans or interleaved into a single scan.
Each frame and scan is preceded with a header containing optional
definitions for compression parameters like quantization tables and
Huffman coding tables. The headers and optional parameters are
identified with "markers" and comprise a marker segment; each scan
appears as an entropy-coded bit...