MEDIANET

Multiprocessing Active Video Transcoder

User’s Manual

Internal Release Version 1.01 (DRAFT)
Medianet Laboratory, Kent State University
October 9, 2000
comments/bugreport: comments@medianet.kent.edu

We are developing the Active Video Transcoder (AVT) system that can perform full range of video transformation on an MPEG-2 video bit-stream system developed at the Kent MEDIANET lab. The AVT can be dynamically installed and activated on network splice-points inside an Active Network. The AVT system can generate a new bit-stream matching the network characteristics and receiver requirement downstream.

However, MPEG-2 full logic stream transcoding is a daunting computational task. Kent MEDIANET lab is currently investigating the requirements for high performance active networking. As a part, we are outlining the architectural requirements for multi-processing video transcoding. This document accompanies the multiprocessing AVT software that we have implemented for concept demonstration.

This experimental system transcodes ISO-/IEC 13818-2 stream on an Active Router with multiprocessor configuration. The system takes advantage of both kernel level default process scheduling or PSET based explicit process scheduling mechanism implemented in IRIX and Red Hat LINUX.

It provides brief instructions on how to install and run the Active Video Transcoder (AVT). This is an interim distribution of a system under development and has been tested only on a limited platform, and is intended for internal use only.

[ Installation and Compilation | Test Run | General Usage]

Distribution:

The distribution is a tar file format. Follow the steps below to compile it.
1. Compiling environments.
Compilation needs gcc compiler or compatible one. Typically the compilation is done with most UNIX operating systems.

2. Extracting file.
Use tar command to extract it.

% tar xvf p1.2.tar

3. Compile it.
In the top most directory of the extracted files, there is a "Makefile." Run "make" in the directory to compile it.

Sample Run:

After compile the sources, you have executable files in decoder and encoder directory. There is a “test” directory for testing this transcoder. Change to the test directory and run “runme” script file.

It invokes a decoder with a m.m2v video file already placed there. The decoder analyze the stream and invoke encoders per a GOP. After transcoding the decoder gathers the transcoded stream and stores it into an output file out.m2v. Please check the “runme” script for further custom run.

Acknowledgement: The development of this research has been supported by a DARPA research grant. Also the code has been developed based on Barkley MPEG-2 encoder and decoder.