audio(1audio)

Name
audio - TSP Audio Programs

Description
The AFsp package provides several audio file utility programs and a library of routines for reading and writing audio files.

Audio File Utilities
    CompAudio
        Compare audio files, producing statistics and signal-to-noise ratio figures.
    CopyAudio
        Copy audio files. This program combines samples from input audio files (an arbitrary linear combination) and writes them to the output file in a user selectable format. One application is to provide format conversion for an audio file; another is to combine samples from multi-channel files.
    FiltAudio
        Filter audio files. This program filters an audio file with an FIR, IIR or all-pole filter. This program can be used with an appropriate filter for sample rate conversion. The AFsp package includes a number of filter from the ITU-T Software Tool Library (G.191) in a form that can be used directly with the FiltAudio program.
    GenNoise
        Generate noise. This program generates an audio file containing Gaussian white noise.
    GenTone
        Generate a sinusoid. This program generates an audio file containing a sine wave of a given amplitude and frequency.
    InfoAudio
        Display information about an audio file.
    LPanal
        Demonstration program to do LPC analysis on a speech file.
    LPsyn
        Demonstration program to do LPC synthesis from a residual file.
    ResampAudio
        Resample data from an audio file. This process involves interpolating between the samples in the original file to create a new sequence of samples with a new spacing (sampling rate).
    SunAudioPort
        Change the gain, balance and port settings for a Sun audio device.
    SunPlay
        Play any of the audio file types supported by the AFsp routines on a Sun audio device.

Audio File Library Routines
The audio file open routine automatically senses the input file type. The data format for the file is passed to the audio file reading routines. The audio file reading routine does byte swapping and format conversion on the fly as the file is read. The user sees float data without needing to worry about the underlying data format.

Once a file is opened for writing, the user calls routines which take the user's float data and do byte swapping and format conversion of the data transparently.

The library routines supplied in AFsp package form part of the libtsp signal processing library. The AFsp routines are written in C and have been tested on Unix and Windows.
    AFclose
        Close an audio file
    AFopenRead
        Open an audio file for reading
    AFopenWrite
        Open an audio file for writing
    AFreadData
        Read data from an audio file (return float values)
    AFsetFileType
        Explicitly set the input audio file type
    AFsetHinfo
        Set the audio file header information string
    AFsetNHpar
        Set defaults for headerless audio files
    AFwriteData
        Write data to an audio file (float input values)

Audio File Formats
The following file formats are supported for reading.

    Headerless audio files

    AU audio files

    RIFF WAVE files

    AIFF/AIFF-C audio files

    NIST SPHERE audio files

    IRCAM soundfiles

    INRS-Telecom audio files

    ESPS sampled data feature files

    Comdisco SPW Signal files

    Text audio files

The following file formats are supported for writing.

    Headerless audio files (including text data)

    AU audio files

    RIFF WAVE files

    AIFF-C audio files

Audio File Data Types
The following (uncompressed) data types are supported.

    8-bit mu-law and A-law

    8-bit signed and unsigned fixed-point

    9-bit to 32-bit signed fixed-point

    32-bit floating-point

    64-bit floating-point

    text data

See Also
InfoAudio CompAudio ConcatAudio CopyAudio GenNoise LPanal LPsyn ResampAudio SunAudioPort SunPlay