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WAV (.wav)

  • Import and Export support all audio codecs commonly used in the WAV format, including RF64 to store files larger than 4GB.
  • Background & Context

      • MIME type: audio/x-wav
      • Microsoft WAV audio format.
      • Used for storage and interchange of audio data on Windows, in audio recording and processing, and on the web.
      • Binary file format.
      • Known as wave form audio format.
      • Variant of the Microsoft RIFF bitstream format.
      • Typically stores uncompressed sampled audio as pulse-code modulation (PCM) data.
      • Also supports several codecs for compressed audio.
      • Supports arbitrary sampling frequency, arbitrary number of channels, and arbitrary bit depth.

    Import & Export

    • Import["file.wav"] imports a WAV file, returning an audio object.
    • Import["file.wav",elem] imports the specified element from a WAV file.
    • The import format can be specified with Import["file","WAV"] or Import["file",{"WAV",elem,}].
    • Export["file.wav",expr] exports an audio or sound object to a 16-bit WAV file.
    • Sound objects including notes are rasterized to sampled audio.
    • See the reference pages for full general information on Import and Export.
    • ImportString and ExportString support the WAV audio format.

    Import Elements

    • General Import elements:
    • "Elements"list of elements and options available in this file
      "Rules"full list of rules for each element and option
      "Options"list of rules for options, properties, and settings
    • Data representation elements:
    • "Audio"audio signal given as an Audio object
      "AudioFile"audio signal given as an out-of-core Audio object
      "Data"raw audio samples, given as a list of real numbers, each sublist representing an individual audio channel
      "SampledSoundList"audio signal given as a SampledSoundList object
      "Sound"audio signal given as a Sound object
    • Import by default uses the "Audio" element for short WAV files and the "AudioFile" element otherwise.
    • Advanced Import element:
    • "AudioChannels"number of audio channels
      "AudioEncoding"audio encoding
      "Duration"duration of the audio given in seconds
      "Length"number of samples
      "SampleDepth"number of bits used to store every sample
      "SampleRate"number of amplitude samples per second and channel
    • Metadata elements:
    • "MetaInformation"interpreted as quantities, locations, dates, numbers, etc.
      "RawMetaInformation"uninterpreted as strings and numbers
    • Available metadata tags include "ID3v2".


    • Import and Export option:
    • "AudioChannels"Automaticnumber of audio channels
      IncludeMetaInformationAllmetadata types to import and export
      SampleRateAutomaticsamples per second for each channel
    • Export options:
    • "AudioEncoding""Integer16"how samples are encoded
    • If the sample rate is not specified when exporting to WAV, the highest sample rate occurring in the exported sound is used, and all sounds are resampled as necessary.
    • If the number of channels is unspecified, the highest number of simultaneous channels is taken, and silence is inserted if necessary.
    • If "AudioChannels" is set to a value n that is less than the number of channels to be exported, only the first n channels are exported.
    • The WAV format supports PCM (pulse-code modulation) and ADPCM (adaptive differential pulse-code modulation) codecs, and various other audio encoding algorithms.
    • "AudioEncoding" can be set to any of the following codecs:
    • "UnsignedInteger8"Unsigned 8-bit PCM
      "Integer16"16-bit PCM
      "Integer24"24-bit PCM
      "Integer32"32-bit PCM
      "Real32"32-bit IEEE floating point
      "Real64"64-bit IEEE floating point
      "aLaw"a-Law 4-bit PCM (ITU-T G.711)
      "uLaw"μ-Law 4-bit PCM (ITU-T G.711)
      "IMA-ADPCM"IMA 4-bit ADPCM
      "MS-ADPCM"Microsoft 4-bit ADPCM
      "GSM610"GSM 6.10 codec (ETSI 6.10 standard)
    • Not all codecs support arbitrary sample rates and channel specifications.
    • Supported IncludeMetaInformation settings are: "ID3v2", "RawID3v2", All and None.


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    Basic Examples  (2)

    This imports a WAV file:

    Use Play to generate sampled sound and export it to WAV:

    Export it to WAV:

    Export to 24-bit WAV:

    Scope  (3)

    Import Elements  (16)

    Import Options  (6)

    Export Options  (4)

    Introduced in 1999 (4.0) | Updated in 2017 (11.2) 2020 (12.1)