70 lines
2.0 KiB
Markdown
70 lines
2.0 KiB
Markdown
node-lame
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=========
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### NodeJS native bindings to libmp3lame & libmpg123
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[](https://travis-ci.org/TooTallNate/node-lame)
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For all your async streaming MP3 encoding/decoding needs, there's `node-lame`!
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This module hooks into libmp3lame, the library that the `lame` command uses, to
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provide `Encoder` and `Decoder` streams to NodeJS.
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Installation
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------------
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`node-lame` comes bundled with its own copy of `libmp3lame` and `libmpg123`, so
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there's no need to have them installed on your system.
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Simply compile and install `node-lame` using `npm`:
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``` bash
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$ npm install lame
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```
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Example
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-------
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Here's an example of using `node-lame` to encode some raw PCM data coming from
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`process.stdin` to an MP3 file that gets piped to `process.stdout`:
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``` javascript
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var lame = require('lame');
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// create the Encoder instance
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var encoder = new lame.Encoder({
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// input
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channels: 2, // 2 channels (left and right)
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bitDepth: 16, // 16-bit samples
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sampleRate: 44100, // 44,100 Hz sample rate
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// output
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bitRate: 128,
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outSampleRate: 22050,
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mode: lame.STEREO // STEREO (default), JOINTSTEREO, DUALCHANNEL or MONO
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});
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// raw PCM data from stdin gets piped into the encoder
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process.stdin.pipe(encoder);
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// the generated MP3 file gets piped to stdout
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encoder.pipe(process.stdout);
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```
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See the `examples` directory for some more example code.
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API
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---
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### Decoder class
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The `Decoder` class is a `Stream` subclass that accepts MP3 data written to it,
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and outputs raw PCM data. It also emits a `"format"` event when the format of
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the MP3 file is determined (usually right at the beginning).
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### Encoder class
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The `Encoder` class is a `Stream` subclass that accepts raw PCM data written to
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it, and outputs a valid MP3 file. You must specify the PCM data format when
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creating the encoder instance. Only 16-bit signed samples are currently
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supported (rescale before passing to the encoder if necessary)...
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