audio-mpg123

A native node binding to write raw PCM data to an OS driver.

This is a pure native node binding for the library mpg123. This is used particularly with audio-speaker which provides a nice API over this native binding to play audio.

It is highly recommended you use audio-speaker if you are looking for a way to play audio. Please look at audio-speaker before using this module.

Install

Basic install (pre-built): npm install audio-mpg123

Advanced install is not recommended at this time as it is difficult to use at production. We are working on a fix for this.

Usage

mpg123.create(finish)

Creates new out123_handle and returns pointer that is used in subsequent calls. The finish param is a callback as finish(success) with either 1 or 0.

var pointer = mpg123.create(function (success) {
  if (success === 0) {
    // ...
  }
})

mpg123.open(pointer, sampleRate, channels, encoding, finish)

Start out123 with sampleRate, channels, and encoding. The finish param is a callback as finish(success) with either 1 or 0

mpg123.open(pointer, 44100, 2, mpg123.MPG123_ENC_FLOAT_32, function (success) {
  if (success === 0) // ...
})

The different formats are constants in the form of:

mpg123.MPG123_ENV_<SIGNED|UNSIGNED>_<8|16|24|32>
mpg123.MPG123_ENV_FLOAT_<32|64>

This specifies if it is signed/unsigned, the bitdepth, and if it is a float.

mpg123.write(pointer, buf, length, finish)

Write to out123 with buf and length. finish is called as finish(success) with 1 and 0

mpg123.write(pointer, buf, buf.length, function (success) {
  if (success === 0) // ...
})

mpg123.flush(pointer, finish)

Flush out123 (clears write buffer) and handle finish(success) with either 1 or 0

mpg123.flush(pointer, function (success) {
  if (success === 0) // ...
})

mpg123.close(pointer, finish)

Close out123 and handle finish(success) with either 1 or 0

mpg123.close(pointer, function (success) {
  if (success === 0) // ...
})

Support

Out123 Version: 2

The following device support table below only applies to those wanting the pre-built binary.

Operating System	Node	Arch	Driver
Windows	4.x, 6.x, 7.x	x64	win32
Linux	4.x, 5.x, 6.x, 7.x	x64	alsa

It is important to note that if you need support other than what's in this table, it is possible to build the binary yourself.

NOTE: Windows, Linux and MacOS are currently the only supported operating systems. We are unable to provide a prebuilt binary for Windows ia32 and MacOS x64 at this time and when you install the module, you will need build tools to build it yourself.

Credits

Connor Hartley	Jamen Marz