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ResearchChannel/I2. Working Group What is MPEG-4. L. Ross M. Wellings www.researchchannel.com. Compression. A Brief History MPEG-1 MPEG-2 MPEG-7 MPEG-4. MPEG-1. VHS quality video with audio 1989-1991 Approximately 1.2 Mbps Being replaced. MPEG-2.
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ResearchChannel/I2 Working Group What is MPEG-4 L. Ross M. Wellings www.researchchannel.com
Compression • A Brief History • MPEG-1 • MPEG-2 • MPEG-7 • MPEG-4
MPEG-1 • VHS quality video with audio • 1989-1991 • Approximately 1.2 Mbps • Being replaced
MPEG-2 • Broadcast quality video with audio • 1990-1995 • Up to 15 Mbps @ ML • Not interactive • Best viewing • MPEG-3 collapsed in MPEG-2
MPEG-2 • Research Channel has 400 hours of MPEG-2 programs • Searching, evaluating new products
Types of MPEG-2 • MP@LL (Main Profile at Low Level) • MP@ML (Main Profile at Main Level) • 4:2:2: Profile@ML (4:2:2:Profile at Main Level) • MP@HL (Main Profile at High Level)
MPEG-7 • Search Interface • 1997-2000 • Not here yet • Not a compression scheme at all, but a description system for multimedia content.
MPEG-4 • Low bit rate • Is a standard for video, audio, graphics i.e. multimedia compression with general interactivity • Began July 1993 / Release February 2000 • Goal: to make low-bit rate files
Problems with MPEG-4 • Not broadcast quality • Not a replacement for MPEG-2 • Full specification not complete as yet • Not fully supported by Microsoft or Apple • Not inexpensive or easy (potentially high production cost) • Fast processor required at client end • Lack of interactive tools
Advantages to MPEG-4 • Replacement for MPEG-1 • Better quality • Smaller files • More robust
Applications MPEG-4 is Suitable for: • Low bit-rate streaming • Audio, video, V.O.D. and webcast Example: ResearchChannel web site • Webcams • FUTURE: games, wireless, mobile, personal conferencing • Future Future • Highly interactive Web sites • Complex network-based software
Recommendations • Use for low bit-rate applications • Delay implementation of interactive content • Only beta tools available • Process is complex • Process is very new and little understood • Entire project must be fully planned from production to client
What is Interactivity? User Access to Information Random access to information, user chooses
How does MPEG-4 Become Interactive • Decoder-Based Compositing • Picture elements dissembled by the encoder into objects, multiplexed, and transmitted. • Picture elements are demultiplexed by the decoder, and composited according to: • Pre-produced rules • User selections
How does MPEG-4 Become Interactive • Manipulation of objects of delivery system • Embedded hotlinks • Interactive control of delivery system • Future: Possible to create new experience at the client end
Considerations • Hardware and Software Requirements • Processor speed • Software client • Software and hardware integration
Simple Interactivity: • Play • Forward • Rewind • Mouse Clicks
Complex Interactivity • Hotlinks • Camera choices • Embedded video • Embedded Ads • Pop-up windows • Rotation of objects • Animation
For Millionaires • Create new information! • 10 Camera shoots • Encode every element as object • Have editor spend thousands of hours on possibilities • Invent REALLY FAST processors • Move objects around • Change Background
For Millionaires • Think - ”special effect studio with hundreds of employees” • intellectual property considerations
MPEG-4 Production Implications • Video objects can be any shape • Considerations • number of objects • size of objects • coding tools • MPEG-4 s/w decoders required for special function • fast processors • lots of memory , bandwidth