WAVEFORMATEX: Difference between revisions

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(Link to xWMA page, mention WAVEFORMAT and WAVEFORMATEXTENSIBLE, explain extradata)
m (Typo)
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  bytes 18..  extradata [actual number of bytes is determined by cbSize field]
  bytes 18..  extradata [actual number of bytes is determined by cbSize field]


It is an extension of the WAVEFORMAT data structure, which is exactly 16 bytes long and omits the cbSize field and the associated extradata).
It is an extension of the WAVEFORMAT data structure, which is exactly 16 bytes long and omits the cbSize field and the associated extradata.


It is a subset of the [[WAVEFORMATEXTENSIBLE]] structure, which is typically used for data with more than two channels. A WAVEFORMATEXTENSIBLE structure can be recognized by wFormat being equal to 0xfffe.
It is a subset of the [[WAVEFORMATEXTENSIBLE]] structure, which is typically used for data with more than two channels. A WAVEFORMATEXTENSIBLE structure can be recognized by wFormat being equal to 0xfffe.


[[Category:Multimedia APIs]]
[[Category:Multimedia APIs]]

Revision as of 05:15, 11 April 2011

The WAVEFORMATEX data structure defines common properties of an audio stream and occurs in a variety of multimedia file formats, including:

Since the format originated on Windows/Intel computers, the defined, multi-byte numbers are stored in little endian format, even if the data structure appears in QuickTime files.

bytes 0-1    wFormat
bytes 2-3    nChannels
bytes 4-7    nSamplesPerSec
bytes 8-11   nAvgBytesPerSec
bytes 12-13  nBlockAlign
bytes 14-15  wBitsPerSample
bytes 16-17  cbSize
bytes 18..   extradata [actual number of bytes is determined by cbSize field]

It is an extension of the WAVEFORMAT data structure, which is exactly 16 bytes long and omits the cbSize field and the associated extradata.

It is a subset of the WAVEFORMATEXTENSIBLE structure, which is typically used for data with more than two channels. A WAVEFORMATEXTENSIBLE structure can be recognized by wFormat being equal to 0xfffe.