by Neil Ridgway

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FOHMRTSPApplying Open Hypermedia and Temporal
Linking to Audio Streams

• by Neil Ridgway

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Contents

• Introduction
• WWW and Audio
• Streaming Protocols and RTSP
• OHSs and Audio
• FOHM
• My Research
• Conclusion

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Introduction

• Both the WWW and OHSs can create links
• to and from text and images
• only to temporal media (audio and video)
• The WWW
• streaming media protocols for delivery
• embedded links
• OHSs
• no streaming protocols
• link information handled separately

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WWW and Audio

• Originally download entire audio file.
• Can now stream audio information to users.
• Synchronised Multimedia Integration Language
  (SMIL) Version 1 - PowerPoint for the Web.

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Streaming Media Protocols

• De facto standards
• RFC 1889 Real-time Transport Protocol (RTP)
• RFC 2326 Real Time Streaming Protocol (RTSP)
• RTP encoding of the packets and delivery
  (usually over UDP).
• RTSP network remote control.

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Real Time Streaming Protocol
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OHSs and Audio

• Audio domain neglected because
• lack of technology
• HCI challenges
• audio file formats
• Microcosms SoundViewer and HyperWaves Harmony
  Audio Player.

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Fundamental Open Hypermedia Model (FOHM)

• Derived from Open Hypermedia Protocol.
• Interoperable higher-level data structure.
• Designed to work across multiple domains e.g.
  navigational hypertext.
• Defined as a XML DTD.

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My Research FOHMRTSP

• New RTSP implementation
• to support IPv6 (future proofing)
• to control audio streams
• New RTSP implementation extensions
• to support FOHM linkbases
• to provide Open Hypermedia and Temporal Linking
  functionality.

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Extensions to RTSP

• The new methods
• The AVAILABLE_LINKS method.
• The FOLLOW_LINK method.
• The CREATE_LINK method.
• Link information stored in separate FOHM
  linkbases.

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Conclusion

• FOHMRTSP mutually beneficial relationship.
• First application of FOHM to stream media.
• Several issues
• preloading the links
• infinite streams (radio broadcast)