Sustainability of Digital Formats
Planning for Library of Congress Collections
Sustainability of Digital Formats
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| Introduction | Sustainability Factors | Content Categories | Format Descriptions | Contact | |
| Full name | Vorbis Audio Codec, Version I |
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| Description | Bitstream encoding format designed for efficient distribution of waveform sound over moderate bandwidth connections; may be used at higher data rates for better fidelity. From an open source project. The Vorbis specification states: " . . . a general purpose perceptual audio CODEC intended to allow maximum encoder flexibility, thus allowing it to scale competitively over an exceptionally wide range of bitrates." |
| Production phase | Generally used for final-state, end-user delivery. |
| Relationship to other formats | |
| Used by | Ogg_Vorbis, Ogg Vorbis Audio Format |
| LC experience or existing holdings | None. |
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| LC preference | See Ogg_Vorbis. |
| Disclosure | Fully documented. Developed by the Xiph.Org Foundation, a non-profit organization. |
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| Documentation | Vorbis I specification. This writer has found two slightly different versions at this URL (at different times); one with an internal date of 2004-04-06 and one dated 2004-07-20 (available as of September 12, 2007, with a full title of "* 0.8* 1.2Vorbis I specification"). |
| Adoption | Applications include streaming broadcasts ("oggcasts") and computer games. See also Ogg and Ogg_Vorbis |
| Licensing and patents | None. |
| Transparency | Depends upon algorithms and tools to read; requires sophistication to build tools. Open source documentation supports tool building. |
| Self-documentation | For "file" metadata, see Ogg. Technical metadata is included in the Vorbis stream. This is described in the RTP Payload Format for Vorbis Encoded Audio (draft-ietf-avt-rtp-vorbis-06). The June 2007 draft at http://www.ietf.org/internet-drafts/draft-ietf-avt-rtp-vorbis-07.txt expires in December 2007. Since this Web page may not be updated promptly, the link this IETF document is has not been embedded here. |
| External dependencies | Surround sound requires appropriate amplifier and loudspeakers or headphone. |
| Technical protection considerations | None known to the compilers of this document. |
| Sound | |
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| Normal rendering | Good support. |
| Fidelity (high audio resolution) | From the specification: "At the high quality/bitrate end of the scale (CD or DAT rate stereo, 16/24 bits) it is in the same league as MPEG-2 and MPC. Similarly, the 1.0 encoder can encode high-quality CD and DAT rate stereo at below 48kbps without resampling to a lower rate. Vorbis is also intended for lower and higher sample rates (from 8kHz telephony to 192kHz digital masters). . . ." |
| Multiple channels | From the specification: Supports "a range of channel representations (monaural, polyphonic, stereo, quadraphonic, 5.1, ambisonic, or up to 255 discrete channels)." |
| Support for user-defined sounds, samples, and patches | Not supported. |
| Functionality beyond normal rendering | Not fully investigated for this page; may be streamed as raw data under RTP (Realtime Transport Protocol). |
| General | |
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| History |
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