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AVI OpenDML with Motion JPEG Video

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Format Description Properties Explanation of format description terms

Identification and description Explanation of format description terms

Full name AVI OpenDML with Motion JPEG Video
Description File format that wraps a series of JPEG images with other data chunks, e.g., audio, in AVI_OpenDML_1_02, to produce a moving image sequence, referred to as Motion JPEG (MJPEG). The images represent individual frames (or fields? Comments welcome) from a pre-existing video recording, generally analog. The images employ a form of the JPEG still image compression algorithm, as specified by AVI_OpenDML_1_02. Microsoft refers to this encoding as JPEG DIB (Device Independent Bitmap). See Notes for more information.
Production phase Generally a middle-state or final-state format.
Relationship to other formats
    Subtype of AVI_OpenDML_1_02, AVI File Format with OpenDML Extensions
    Contains MJPEG, MJPEG (Motion JPEG) Video Codec
    May contain WAVE, WAVE Audio File Format. For audio interleaved with video.
    May contain MP3_CBR, MP3, Constant Bit Rate. For audio interleaved with video

Local use Explanation of format description terms

LC experience or existing holdings  
LC preference See AVI.

Sustainability factors Explanation of format description terms

Disclosure See AVI, AVI_OpenDML_1_02, and JPEG.
    Documentation See AVI, AVI_OpenDML_1_02, and JPEG.
Adoption AVI and AVI_OpenDML_1_2 are widely adopted for video production and filemaking; in 2000, the expert commentator John McGowan wrote, "Most PC video capture and editing systems capture video to AVI files using Motion JPEG video compression."
    Licensing and patents See AVI and AVI_OpenDML_1_02
Transparency See AVI, AVI_OpenDML_1_02, and MJPEG.
Self-documentation See AVI and AVI_OpenDML_1_02
External dependencies See AVI and AVI_OpenDML_1_02
Technical protection considerations See AVI and AVI_OpenDML_1_02

Quality and functionality factors Explanation of format description terms

Moving Image
Normal rendering Good support.
Clarity (high image resolution) Moderate to very good, depending on the compression quality level applied.
Functionality beyond normal rendering See AVI and AVI_OpenDML_1_02

File type signifiers and format identifiers Explanation of format description terms

Tag Value Note
Filename extension avi
 
Internet Media Type See related format.  See AVI and AVI_OpenDML_1_02
Magic numbers See related format.  See AVI and AVI_OpenDML_1_02
Microsoft FOURCC MJPG
See the archived version of the Microsoft registry of FOURCC and WAVE codes mounted by IANA.

Notes Explanation of format description terms

General

Avery Lee, writing in the rec.video.desktop newsgroup in 2001, commented that "MJPEG, or at least the MJPEG in AVIs having the MJPG fourcc, is restricted JPEG with a fixed -- and *omitted* -- Huffman table. The JPEG must be YCbCr colorspace, it must be 4:2:2, and it must use basic Huffman encoding, not arithmetic or progressive. . . . You can indeed extract the MJPEG frames and decode them with a regular JPEG decoder, but you have to prepend the DHT segment to them, or else the decoder won't have any idea how to decompress the data. The exact table necessary is given in the OpenDML spec."

History

OpenDML was initially developed in 1996-97 to support the carriage of MJPEG (Motion JPEG), with frames are encoded as JPEG-DIB (Device-Independent Bit compression). Subsequently, the "OpenDML extensions," as they are called, have come into wide use for video codecs, in large part because they permit the creation of the large files needed to carry video data at medium or high resolution.


Format specifications Explanation of format description terms


Useful references

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Last Updated: Tuesday, 21-Feb-2017 07:56:37 EST