Difference between revisions of "DVI IMA ADPCM"

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== DVI4 ==
 
== DVI4 ==
  
The [https://www.freesoft.org/CIE/RFC/1890/10.htm DVI4] codec, as defined in [https://www.freesoft.org/CIE/RFC/1890/index.htm RFC1890] is a variant of [[IMA ADPCM]] where, unlike [[IMA ADPCM]] where the header stores the first sample, in DVI4 the header stores the initial predictor state.  
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The [https://www.freesoft.org/CIE/RFC/1890/10.htm DVI4] codec, as defined in [https://www.freesoft.org/CIE/RFC/1890/index.htm RFC1890] is a variant of [[IMA ADPCM]].
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In DVI4 the block header stores the initial predictor state, unlike [[IMA ADPCM]] where the block header stores the first sample.
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Otherwise, DVI4 is decoded identically to [[IMA ADPCM]].
  
 
[[Category:Audio Codecs]]
 
[[Category:Audio Codecs]]
 
[[Category:ADPCM Audio Codecs]]
 
[[Category:ADPCM Audio Codecs]]
 
[[Category:IMA ADPCM Audio Codecs]]
 
[[Category:IMA ADPCM Audio Codecs]]

Latest revision as of 19:30, 11 October 2018

According to the XAnim multimedia application, there are two variants of DVI IMA ADPCM, both of which are encoded and decoded with the IMA ADPCM algorithm. The original variant encodes the top nibble of a byte first, then the bottom nibble. The revised variant has the opposite encoding order.

DVI4

The DVI4 codec, as defined in RFC1890 is a variant of IMA ADPCM. In DVI4 the block header stores the initial predictor state, unlike IMA ADPCM where the block header stores the first sample. Otherwise, DVI4 is decoded identically to IMA ADPCM.