MP3 (.mp3)

  • Import and Export support the MP3 specification.
  • Background & Context

      • MIME types: audio/mpeg, audio/mpeg3, audio/x-mpeg-3MP3 digital audio format, known as MPEG Audio Layer 3.
      • A lossy compression scheme commonly used for consumer audio streaming, storage, transfer, and playback, which can also be used on the web.
      • Binary file format.
      • Follows the ISO/IEC 11172-3 and ISO/IEC 13818-3 standard.
      • Supports a few sampling frequencies from 8kHz to 48kHz.
      • Supports up to two audio channels.

    Import & Export

    • Import["file.mp3"] imports an MP3 file, returning an audio object.
    • Import["file.mp3",elem] imports the specified element from an MP3 file.
    • The import format can be specified with Import["file","MP3"] or Import["file",{"MP3",elem,}].
    • Export["file.mp3",expr] exports an audio or sound object to an MP3 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 MP3 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 MP3 files and the "AudioFile" element otherwise.
    • Advanced Import element:
    • "AudioChannels"number of audio channels
      "Duration"duration of the audio given in seconds
      "Length"number of samples
      "SampleRate"number of amplitude samples per second and channel
    • Metadata elements:
    • "MetaInformation"interpreted metadata as quantities, dates, locations, etc.
      "RawMetaInformation"uninterpreted metadata including strings and numbers only
    • Available metadata tags include ID3v1, ID3v2 and APE.
    • Multiple channels are represented as an array of audio samples.

    Options

    Examples

    open all close all

    Basic Examples  (2)

    Import an MP3 file:

    Generate an audio signal and export to MP3:

    Scope  (4)

    Show all import elements available in this file:

    Import audio properties:

    Generate an audio signal and export to MP3:

    Compare to a size of a WAV file:

    Use ExportString and ImportString with an MP3:

    Import Elements  (14)

    Available Elements  (3)

    List of available elements:

    Get audio-related information as a list of rules:

    Import some audio options:

    The "Options" element does not return all options that are present in the imported audio object:

    Data Representation  (5)

    "Audio"  (1)

    Get an audio signal given as an Audio object:

    "AudioFile"  (1)

    Get an audio signal given as an out-of-core Audio object:

    "Data"  (1)

    Get raw audio samples, given as a list of real numbers:

    Create audio from imported data:

    "SampledSoundList"  (1)

    Get an audio signal given as a SampledSoundList object:

    "Sound"  (1)

    Get an audio signal given as an Sound object:

    Metadata  (6)

    "AudioChannels"  (1)

    Get the number of audio channels:

    "Duration"  (1)

    Get the duration of the audio given in seconds:

    "Length"  (1)

    Get the number of samples:

    "MetaInformation"  (1)

    Get the audio metadata:

    "RawMetaInformation"  (1)

    Get the audio metadata in a raw form:

    "SampleRate"  (1)

    Get the number of amplitude samples per second and channel:

    Import Options  (6)

    "AudioChannels"  (2)

    Generate a stereo MP3 file:

    By default, the number of audio channels is set to be Automatic:

    Specify all the audio channels to be imported:

    Import the second channel only:

    IncludeMetaInformation  (3)

    By default, all available metadata is imported:

    Import an audio file with no metadata:

    Import the audio with only specified classes of metadata:

    SampleRate  (1)

    By default, the sample rate is extracted from the file:

    Specify the sample rate of the imported sound:

    Export Options  (5)

    "AudioChannels" (1)

    By default, the audio is exported using the default number of channels:

    Specify the number of channels of exported audio:

    CompressionLevel (1)

    By default, the audio is exported using the 0.5 compression level:

    Specify the encoding of exported audio:

    IncludeMetaInformation (2)

    By default, all existing metainformation is exported:

    Specify the metadata to include:

    SampleRate  (1)

    By default, the audio is exported using the default sample rate:

    Specify the sample rate of exported audio:

    Introduced in 2014
     (10.0)
     |
    Updated in 2018
     (11.3)