Press Release

    AMSTERDAM, Netherlands--(BUSINESS WIRE)--Sept. 12, 2003--

          DiviCom(R) MV 450 Delivers Flexible Software-based
          Architecture and Superior Compression Rates Needed
                  for Existing and Emerging Services

Harmonic Inc. (Nasdaq:HLIT) today introduced the DiviCom(R) MV 450 high definition digital video encoder, a new addition to its industry leading digital video compression and delivery solutions. With a software-based architecture, superior compression capabilities and more output transport options, this real-time high definition encoder provides the power and flexibility that is essential for delivering value-added high definition broadcast and on-demand services.

Building on Harmonic's leadership in high definition (HD) and standard definition (SD) encoding systems, the new MV 450 incorporates a series of technologies pioneered by Harmonic that enable operators to more effectively address the trade-off between bit rate and picture quality. This is a particularly critical issue with HD services since inefficiently encoded material can easily consume the capacity of several -- perhaps 10 or more -- efficiently encoded, constant bit rate SD programs. As demand for HD services grows, bandwidth efficiency becomes a significant consideration.

"Driven by falling prices of HDTV-capable television sets and increased HD programming from major broadcast and cable networks, more than 10 U.S. million homes will have high-definition TVs by mid-2004," said Adi Kishore, Media and Entertainment Analyst at The Yankee Group. "For video service providers, offering HDTV is becoming increasingly important. HD encoders, like the Harmonic DiviCom MV 450, will be valuable in helping them efficiently manage network bandwidth for their rapidly growing line-up of HD programming."

The MV 450 incorporates a flexible software-based architecture that allows features and capabilities to be added to the system as needed. This architecture -- field-proven in other Harmonic encoders -- provides an added level of "future proofing" to both the encoder and the infrastructure in which it is deployed. Features enabled through the software architecture include digital program insertion (DPI), which allows advertisements to be dynamically inserted into an already compressed digital video stream, and Harmonic's advanced LookAhead feature to maximize encoding efficiency. The encoder also features Dolby-E and VANC closed-captioning data extraction as well as 4:2:0 and 4:2:2 color sampling. In addition, the MV 450 supports 1080i, 720p and 480p formats to meet the requirements of various transmission systems and markets.

The MV 450's advanced features make it ideal for a variety of contribution, distribution and broadcast applications. The variable bit rate (VBR) MV 450, used in conjunction with Harmonic's third generation DiviTrackXE(TM) closed-loop statistical multiplexing system, can handle the most challenging video content -- including fast action sports -- while sharing limited bandwidth with other SD and HD services. Furthermore, its efficiency in constant bit rate (CBR) mode combined with the new native IP output makes it attractive to program originators and network distributors who must convey their HD content jitter-free over wide area networks with a specific level of video quality. This configuration is also well suited for emerging services such as HD switched broadcast -- which allows operators to deliver programming to communities of interest without consuming bandwidth until someone "tunes in" -- and HD video-on-demand.

"Harmonic is an established leader in enabling HD services through both real-time encoding and digital turnaround systems. Our standard and high definition encoders are used by satellite, cable, telecom and terrestrial operators around the world to deliver thousands of high-quality digital television channels to millions of viewers," said Buddy Snow, Vice President of Marketing for Harmonic's Convergent Systems Division. "The utility and versatility of the DiviCom MV 450 will enable new categories of HD services and, as a result, expand the application of Harmonic's digital video systems across the entire content creation and delivery chain."

About Harmonic Inc.

Harmonic Inc. is a leading provider of digital video, broadband optical networking and IP delivery systems to cable, satellite, telecom and broadcast network operators. Harmonic's open standards-based solutions for the headend through the last mile enable customers to develop new revenue sources and a competitive advantage by offering powerful interactive video, voice and data services such as video-on-demand, high definition digital television, telephony and Internet access.

Harmonic (Nasdaq:HLIT) is headquartered in Sunnyvale, Calif. with R&D, sales and system integration centers worldwide. The Company's customers, including many of the world's largest communications providers, deliver services in virtually every country. Visit www.harmonicinc.com for more information.

This press release contains forward-looking statements including, but not limited to, growing demand for HD services, more than 10 million U.S. homes having high-definition TVs by mid-2004, the increasing importance of offering HDTV for video service providers, the value of HD encoders in efficiently managing network bandwidth, and the MV 450 enabling new categories of HD services, within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. In addition, actual results could differ materially from those projected in the forward-looking statements as a result of the risk factors set forth in documents that Harmonic files with the SEC, including reports on Form 10-K and 10-Q.

EDITOR'S NOTE -- Product and company names used herein are trademarks or registered trademarks of their respective owners.

    CONTACT: AxiCom (for Harmonic)
             Stephen Orr, +44-20-8600-4613 or 408-543-2360
             Media Relations
             stephen.orr@axicom.com
                  or
             StreetConnect (for Harmonic)
             Michael Newman, 408-542-2760
             Investor Relations
             mnewman@stct.com

    SOURCE: Harmonic Inc.