No examples found in IANA MIME Media Types. Good to excellent, given that the options for audio are those available in the MP3_CBR and WAVE formats.įile type signifiers and format identifiersįrom. However, some desirable technical information is not well represented in the metadata see Notes.ĭepends upon the codec selected, with uncompressed or lossless codecs providing excellent clarity. Technical information is provided in header chunks (e.g., hdrl, movi, and others) descriptive metadata may appear in a RIFF INFO chunk. The AVI file wrapper is transparent the encoded video bitstreams carried in the wrapper require tools and documentation to decode. None known to the compiler of this resource. Adoption may not extend to all permitted codecs and other features. Widely adopted for video production and filemaking. Some additional citations in Useful references below. Additional information may be found at John McGowan's AVI Overview and. Specifications available from third parties for example, the Multimedia Programming Interface and Data Specifications 1.0 (Issued as a joint design by IBM Corporation and Microsoft Corporation, August 1991), is available online from (link available through Internet Archive) and other sites. Proprietary file format developed by Microsoft and IBM as part of RIFF, the Resource Interchange File Format for Windows 3.1. For web access: MPEG-4_AVC (profile unknown).įully documented. After 2000, the files for web service were reproduced in the MPEG-4_AVC (profile unknown).įor preservation reformatting, the Library of Congress' Packard Campus for Audio-Visual Conservation has chosen losslessy-compressed JPEG 2000 encoded video wrapped in MXF. These AVI files were retired and replaced by MPEG-1 and QuickTime files in 19. Microsoft Resource Interchange File FormatĪVI File Format with OpenDML Extensions, Version 1.02ĪVI files containing streams produced by other video codecs, not documented at this time.Īmerican Memory produced AVI_Indeo files in 19, using version 3.1 or 3.2 of the Indeo codec, at 15 fps and 320x240 pixels, and yielding a data rate of about 188 Kb/s. Used as a master format, as a middle-state format, and as a final state format for enduser delivery. Other AVI limitations are described in the Notes, which also provide comments on the evolution of the AVI format. One important shortcoming is limited file size: the single RIFF AVI chunk, in a FAT16 filesystem, limits file size to 2 GB commentators state that the OpenDML extensions permit files as large as 32 TB in an NTFS filesystem. These extensions are unofficially dubbed AVI 2.0, and they are supported by Microsoft and help address some of the shortcomings of the original AVI format described here. (The codecs are also identified by FOURCC tags.) A third optional subchunk is tagged idx1 and it indexes the offsets of the data chunks within the file.ĪVI was first specified in 1992 and, according to the Wikipedia AVI article (consulted February 25, 2016), most AVI files today employ the 1996 OpenDML extensions see the separate AVI_OpenDML_1_02 description. The second subchunk is tagged movi and it carries the actual picture and sound data, which may employ a wide range of codecs, including those listed under Relationships below. The first subchunk is tagged as hdrl and plays the role of file header, providing metadata about the video, such as width, height and frame rate. AVI files consist of one RIFF "chunk" tagged as AVI and divided into "subchunks," each identified by Microsoft's FOURCC four character code. File format for moving image content that wraps a video bitstream with other data chunks and supports synchronous picture-sound playback.
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