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 | WAVE. Waveform Audio File Format |
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| Description | File format for audio. Wrapper file format that can incorporate an audio bitstream with other data chunks. The default bitstream encoding is the Microsoft Pulse Code Modulation (LPCM) format. |
| Relationship to other formats | |
| Subtype of | RIFF, Resource Interchange File Format for Windows 3.1 |
| Has subtype | WAVE_LPCM, WAVE Audio File Format with LPCM Audio |
| Has subtype | WAVE_LPCM_BWF, Broadcast WAVE Audio File Format |
| May contain | LPCM, Linear Pulse Code Modulation audio encoding |
| May contain | µ-Law, µ-Law (Mu-Law) Compressed Sound Format |
| May contain | A-Law, A-Law Compressed Sound Format |
| May contain | DPCM, Differential PCM Sound Format |
| May contain | ADPCM, Adaptive Differential PCM Sound Format |
| LC experience or existing holdings | See WAVE_LPCM |
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| LC preference | See WAVE_LPCM |
| Disclosure | Fully documented. Documentation freely available. Proprietary format developed by Microsoft and IBM as part of the Resource Interchange File Format (RIFF) for Windows 3.1. Incorporated into Broadcast Wave standard. |
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| Documentation |
Multimedia Programming Interface and Data Specifications 1.0. IBM Corporation and Microsoft Corporation, August 1991. Available online, e.g., at http://www.tactilemedia.com/info/MCI_Control_Info.html Multimedia Data Standards Update April 15, 1994 at http://www-mmsp.ece.mcgill.ca/Documents/AudioFormats/WAVE/Docs/RIFFNEW.pdf |
| Adoption |
Widely adopted for exchange of broadcast audio and for telephony. Broadcast: Adopted by the European Broadcast Union as the basis for Broadcast Wave (BWF). BWF recommended as the preferred format for the delivery of music recordings to record companies in the Draft Recommendation for Delivery of Recorded Music Projects developed by the Delivery Specifications Committee of the Producer's and Engineer's Wing of the Recording Academy (National Academy of the Recording Arts and Sciences). BWF specified in AES31-3-1999, the Audio Engineering Society's specification for simple project interchange. Also, with uncompressed PCM encoding, a preferred or recommended format for sound in many long-term archives. Examples include Florida Digital Archive, DSpace at MIT, Libraries and Archives Canada. |
| Licensing and patents | No licensing required. |
| Transparency | Depends on audio codec employed for bitstream encoding (which may incorporate compression); see LPCM, µ-Law, A-Law, DPCM, and ADPCM. |
| Self-documentation | Metadata can be placed in the INFO chunk (aka "LIST" chunk with a list type of "INFO") associated with all RIFF files. Additional metadata is a feature of the bext (Broadcast Audio Extension) associated with WAVE_LPCM_BWF (Broadcast WAVE Audio File Format). A further chunk of metadata for the CART/Audio Delivery Extension to BWF has been defined by the Audio Engineering Society in AES46-2002. |
| External dependencies | None |
| Technical protection considerations | None |
| Sound | |
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| Normal rendering | Excellent. |
| Fidelity (high audio resolution) | Varies according to encoding; see LPCM, µ-Law, A-Law, DPCM, and ADPCM. |
| Multiple channels | Requires use of WAVE Format Extensible (WAVE_FORMAT_EXTENSIBLE). See http://www.microsoft.com/whdc/device/audio/multichaud.mspx |
| Functionality beyond normal rendering | Not applicable |
| Tag | Value | Note |
|---|---|---|
| Filename extension | wav |
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| Internet Media Type | audio/wav audio/wave audio/x-pn-wav |
Selected from The File Extension Source. |
| Internet Media Type | audio/x-wav |
From LC web server configuration (Apache) of 2004-04-28. |
| Internet Media Type | audio/vnd.wave |
From http://www.iana.org/assignments/wave-avi-codec-registry. No examples found in IANA MIME Media Types. |
| Magic numbers | Hex: 52 49 46 46 xx xx xx xx 57 41 56 45 66 6D 74 20 ASCII: RIFF....WAVEfmt |
From Gary Kessler's File Signatures Table. |
| Microsoft WAVE format registry | Varies according to the audio codec selected; see the Microsoft registry. |
| General | |
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| History |
Format created by Microsoft and introduced with Windows 3.1. Adopted as basis for European Broadcasting Union (EBU) Broadcast Wave standard. With Windows 2000, Microsoft introduced a WAVE_FORMAT_EXTENSIBLE header which specifies multiple audio channel data (surround sound) along with speaker positions. This enhancement provided for custom extensions to the format chunk. Ambiguity relating to sample types and container sizes in the standard WAV format was also addressed. |
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