Advanced Multimedia Processing Lab -- Projects -- H.263 Video Codec

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Project - Real-Time Low Bit Rate H.263 Video Codec (1999)



Team Member

Khalid Goudeaux
Joseph Huang
Kehua Jiang
Ta-Chien Lin
Jason Lawrence
Deepak Turaga
Salman Yussof

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The goal of this project is to develop key video technology for videoconferencing. In addition to developing a standard compliant video codec, we are also performing research in novel techniques that are not specified by the standards, in order to fine-tune and enhance the coding performance for a large variety of applications.

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Voice communication of today will be replaced by video communication of tomorrow, and fundamental to realizing this future is real-time compression technology based on ITU-T H.26x standard. The standard defines a syntax and the decoder action, but leaves open the questions of how to implement the encoder. What is the characteristics of a high-quality video codec (encoder and decoder) ? Video quality? Frame rate? Compression ratio? Error resiliency? Or, ill-defined real-world user experience?

CMU H.263 codec is developed in-house with software engineering disciplines - designed to be portable and maintainable and serves as a platform for further video research. Many projects here are built upon CMU H.263 codec platform, and several encoding algorithms have been developed to better the quality of video codec.

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System Description


Written in C/C++ with software engineering discipline, our codec can be compiled by any ANSI-C compatible compiler. The codec can be run on any platform, and have been used on Unix, Windows, TI C6x, and Trimedia DSP platforms.

Optional Features

In addition to the baseline support, the following optional features have been supported on SQCIF, QCIF, and CIF:

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Disclaimer: This web page contains the most current public distribution of the CMU H.263+ Decoder. This is currently not  based on the most current work of CMU H.263+ codec development. The performance of this public distribution software  does not accurately depict the best performance of the CMU H.263+ codec (whether encoder or decoder) due to video hardware, network performance, un-optimized windows programming, etc. Please contact Professor Tsuhan Chen for more information in regards to this codec/decoder.

This release (summer 99) of the decoder takes as input a URL just as you would in the address bar of a web browser. A video window display will output the results of the decoded bitstream as the bits are being read from the Internet. This is an example of the "streaming" capabilities of this implementation of H.263+. The program has been written to give the bitstream decoding process higher priority over the video display process. This will account for any flicker or frame skipping in video display. If you are running the decoder under Windows 95 or 98, have the command prompt window selected to decrease on unnecessary pauses. The pauses are due to the operating system's inability to handle threads efficiently.

Click here to download the H.263 video decoder. (Configure the decoder)

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Our work is used by...

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Any suggestions or comments are welcome. Please send them to Ta

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