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 | AVI (Audio Video Interleaved), Indeo Video Codec |
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| Description | File format that wraps an Indeo video bitstream with other data chunks, e.g., audio, in an AVI wrapper. Indeo versions 3.1 and 3.2 employ vector quantization; versions 4 and 5 use forms of wavelet compression. |
| Production phase | Generally a middle-state format (often used as the video source when producing lower-resolution streaming versions); may be used as a final-state format for enduser delivery. |
| Relationship to other formats | |
| Subtype of | AVI, |
| May contain | Indeo_3, video codec |
| May contain | Indeo_4 video codec, not separately documented |
| May contain | Indeo_5, video codec |
| May contain | WAVE, audio (interleaved with video) |
| May contain | MP3_CBR, (constant bit rate) audio (interleaved with video) |
| LC experience or existing holdings | American Memory produced AVI_Indeo files in 1992 and 1993, using version 3.1 or 3.2 of the Indeo codec, options set at 15 fps and 320x240 pixels, and yielding a data rate of about 188 Kb/s. These AVI files were retired and replaced by MPEG-1 and QuickTime files in 1994 and 1995. |
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| LC preference | See AVI. |
| Disclosure | See AVI, Indeo_3, and Indeo_5. |
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| Documentation | See AVI, Indeo_3, and Indeo_5. |
| Adoption | AVI is widely adopted for video production and filemaking; commentator John McGowan writes, "Indeo R3.2 is one of the default Video for Windows codecs." |
| Licensing and patents | See AVI, Indeo_3, and Indeo_5. |
| Transparency | See Indeo_3 and Indeo_5. |
| Self-documentation | See AVI |
| External dependencies | See AVI |
| Technical protection considerations | See AVI |
| Moving Image | |
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| Normal rendering | Good support. |
| Clarity (high image resolution) | Moderate to very good, given that this is a format typically used for compression and does not support interlaced video. Outcome will depend on the version of Indeo employed, the extent of compression, and the encoder used. High resolution work is limited in the Windows environment due to file size limits (2 GB with FAT 16 technology; theoretical 8 GB with later technologies). |
| Functionality beyond normal rendering | See AVI |
| Tag | Value | Note |
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| Filename extension | avi |
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| Internet Media Type | See related format. |
See AVI |
| Magic numbers | See related format. |
See AVI |
| Microsoft FOURCC | IV32 IV41 IV50 |
See the list of FOURCC codes, which also lists a number of additional IV FOURCCs. John McGowan states that IV32 is generally used for Indeo 3; IV41 for Indeo 4, and IV50 for Indeo 5. FOURCC codes are no longer managed by Microsoft, which has developed a new mechanism for identifying rich media types in general. |
| General | |
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| History |
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