Sunday, August 24, 2014

Motion-JPEG in AVI and Motion-JPEG in MOV

There is no document that defines a single standard format that is universally recognized as a complete specification of “Motion-JPEG” for use in all contexts. This raises compatibility concerns about Motion-JPEG video streams from different manufacturers.  

Each particular file format usually has some specification how Motion-JPEG shall be encoded. There are two popular Motion-JPEG file formats, AVI and MOV.  

Microsoft documents their standard format to store Motion-JPEG in AVI files at http://www.fileformat.info/format/bmp/spec/b7c72ebab8064da48ae5ed0c053c67a4/view.htm Motion-JPEG in AVI doesn’t use custom Huffman table. Instead, default Huffman table is always used. That is, each Motion-JPEG frame won’t have DHT marker.  

Apple documents how Motion-JPEG is stored in QuickTime MOV files, with two types of coding, Motion-JPEG format A and Motion-JPEG format B at https://developer.apple.com/standards/qtff-2001.pdf Each field of Motion JPEG format A fully complies with the ISO JPEG specification. Motion-JPEG format B does not support markers. In place of the marker, therefore, QuickTime inserts a header at the beginning of the bitstream.

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