iconv-lite

What is iconv-lite?

The iconv-lite npm package provides utilities for converting character encodings in pure JavaScript. It supports many different encodings and can convert to and from Buffer objects without the need for a native C++ binding. This makes it a lightweight and portable solution for encoding conversion.

What are iconv-lite's main functionalities?

Encoding Conversion

Converts text from one character encoding to another. The example shows how to decode a buffer to a string and encode a string to a buffer using Windows-1251 encoding.

const iconv = require('iconv-lite');

// Convert from an encoded buffer to js string.
const str = iconv.decode(Buffer.from([0x63, 0x61, 0x66, 0xe9]), 'win1251');

// Convert from js string to an encoded buffer.
const buf = iconv.encode('Sample input text', 'win1251');

Streaming Conversion

Provides a streaming interface for encoding conversion. This example demonstrates how to create a read stream from a file and pipe it through iconv-lite's decode stream.

const iconv = require('iconv-lite');
const fs = require('fs');

// Decode stream (from a file, for example)
const readStream = fs.createReadStream('file.txt');
const decodeStream = iconv.decodeStream('win1251');

readStream.pipe(decodeStream);

decodeStream.on('data', function(str) {
  console.log(str); // converted text
});

Encoding Detection

Checks if a particular encoding is supported by iconv-lite. The example checks if UTF-8 encoding is supported.

const iconv = require('iconv-lite');

// Check if encoding is supported
const encodingSupported = iconv.encodingExists('utf-8');

console.log(encodingSupported); // true or false

Other packages similar to iconv-lite

buffer

The 'buffer' package is a Node.js core module that provides a way to handle binary data. It does not offer direct encoding conversion like iconv-lite, but it can be used in conjunction with other modules to achieve similar results.

iconv

The 'iconv' package is similar to iconv-lite but relies on native C++ bindings. It provides more comprehensive encoding support but is not as lightweight or portable as iconv-lite due to its compiled components.

string_decoder

The 'string_decoder' module is a Node.js core module that provides an API for decoding Buffer objects into strings using a specified character encoding. It is less feature-rich compared to iconv-lite and does not support as many encodings.

README

iconv-lite - pure javascript character encoding conversion

Features

• Pure javascript. Doesn't need native code compilation.
• Easy API.
• Works on Windows and in sandboxed environments like Cloud9.
• Encoding is much faster than node-iconv (see below for performance comparison).

Usage

var iconv = require('iconv-lite');

// Convert from an encoded buffer to string.
str = iconv.decode(buf, 'win1251');

// Convert from string to an encoded buffer.
buf = iconv.encode("Sample input string", 'win1251');

Supported encodings

• All node.js native encodings: 'utf8', 'ucs2', 'ascii', 'binary', 'base64'
• All widespread single byte encodings: Windows 125x family, ISO-8859 family, IBM/DOS codepages, Macintosh family, KOI8 family. Aliases like 'latin1', 'us-ascii' also supported.
• Multibyte encodings: 'gbk', 'gb2313'.

Others are easy to add, see the source. Please, participate. Most encodings are generated from node-iconv. Thank you Ben Noordhuis and iconv authors!

Not supported yet: Big5, EUC family, Shift_JIS.

Encoding/decoding speed

Comparison with node-iconv module (1000x256kb, on Ubuntu 12.04, Core i5/2.5 GHz, Node v0.8.7). Note: your results may vary, so please always check on your hardware.

operation             iconv@1.1.3   iconv-lite@0.2.4 
----------------------------------------------------------
encode('win1251')     ~36 Mb/s      ~230 Mb/s
decode('win1251')     ~38 Mb/s      ~130 Mb/s

Notes

Untranslatable characters are set to � or ?. No transliteration is currently supported, pull requests are welcome.

Testing

npm install --dev iconv-lite
vows

# To view performance:
node test/performance.js

TODO

• Support streaming character conversion, something like util.pipe(req, iconv.fromEncodingStream('latin1')).
• Add more encodings.
• Add transliteration (best fit char).
• Add tests and correct support of variable-byte encodings (currently work is delegated to node).