cwebp

[][webp]

[webp]: https://developers.google.com/speed/webp/

[![NPM Package][repo_badge]][repo]
![Build Status][workflow_badge]

[repo_badge]: https://img.shields.io/npm/v/cwebp.svg
[workflow_badge]: https://github.com/Intervox/node-webp/actions/workflows/main.yml/badge.svg?branch=latest
[repo]: https://www.npmjs.com/package/cwebp

node-webp
=========

Node.js wrapper for [cwebp][cwebp] and [dwebp][dwebp] binaries
from [WebP][webp] image processing utility.

[cwebp]: https://developers.google.com/speed/webp/docs/cwebp
[dwebp]: https://developers.google.com/speed/webp/docs/dwebp

Installation

npm install cwebp

$3

You can get latest WebP source, pre-compiled binaries and installation instructions
from its [official website][get_webp.1], or from its [downloads repository][get_webp.2].

Linux users may use [this installation script][get_webp.3]
to automatically download and install the latest WebP binaries:

curl -s https://raw.githubusercontent.com/Intervox/node-webp/latest/bin/install_webp | sudo bash

MacOS users may install WebP using [homebrew][homebrew]:

brew install webp

or [MacPorts][macports]:

sudo port selfupdate
sudo port install webp

If none of it suit your needs, you may [build the WebP utilities yourself][get_webp.4].

[get_webp.1]: https://developers.google.com/speed/webp/download
[get_webp.2]: http://downloads.webmproject.org/releases/webp/index.html
[get_webp.3]: https://raw.githubusercontent.com/Intervox/node-webp/latest/bin/install_webp
[get_webp.4]: https://developers.google.com/speed/webp/docs/compiling
[macports]: http://guide.macports.org/
[homebrew]: http://brew.sh/

WebP versions compatibility

| node-webp version | Fully compatible WebP versions | Partially compatible WebP versions |
| -------------------- | ------------------------------ | ---------------------------------- |
| 0.1.x | all versions | all versions |
| 1.x | 0.4.1 and later | all versions |
| 2.x | 0.5.0 and later | all versions |

Usage

``js
var CWebp = require('cwebp').CWebp;
var DWebp = require('cwebp').DWebp;

var encoder = new CWebp(source_image);
var decoder = new DWebp(source_webp);
`

or

`js
// new is optional
var encoder = CWebp(source_image);
var decoder = DWebp(source_webp);
`

or

`js
// Backward-compatibility with cwebp@0.1.x
var CWebp = require('cwebp');
`

$3

By default node-webp looks for cwebp and dwebp binary in your $PATH.

#### Specifying path as a constructor option

`js
var Webp = require('cwebp');
var binPath = require('webp').cwebp;

var webp = new Webp(source, binPath);
`

#### Changing default behaviour

`js
var CWebp = require('cwebp').CWebp;
CWebp.bin = require('webp').cwebp;

var encoder = new CWebp(source);
`

`js
var DWebp = require('cwebp').DWebp;
DWebp.bin = require('webp').dwebp;

var decoder = new DWebp(source);
`

N.B.: webp npm module provide old webp 0.3.x binaries.

$3

When source is a string node-webp treats it as a file path.

`js
var CWebp = require('cwebp').CWebp;
var DWebp = require('cwebp').DWebp;

var encoder = new CWebp('original.jpeg');
var decoder = new DWebp('converted.webp');
`

It also accepts Buffers and Streams.

`js
var encoder = new CWebp(buffer);
`

`js
var decoder = new DWebp(stream);
`

Note that node-webp will start consuming the input stream
only when .write(), .stream() or .toBuffer() is called.

$3

`js
encoder.write('image.webp', function(err) {
console.log(err || 'encoded successfully');
});
`

`js
decoder.write('image.png', function(err) {
console.log(err || 'decoded successfully');
});
`

#### Getting output image as a Buffer

`js
decoder.toBuffer(function(err, buffer) {
// ...
});
`

#### Getting output image as a readable Stream

`js
var stream = encoder.stream();

stream.pipe(destination);
stream.on('error', function(err) {
// something bad happened
});
`

$3

node-webp supports promises.

`js
encoder.write('image.webp').then(function() {
// ...
});
`

`js
encoder.toBuffer().then(function(buffer) {
// ...
});
`

`js
decoder.stream().then(function(stream) {
// ...
});
`

$3

node-webp provides helper functions for most of cwebp and dwebp conversion options.
For the full list of available helpers see [methods.json][methods] file.

`js
encoder.quality(60);
decoder.tiff();
`

[methods]: https://github.com/Intervox/node-webp/blob/latest/methods.json

#### Sending raw command

`js
encoder.command('-d', 'dump.pgm');
`

#### Providing custom spawn options

`js
encoder.spawnOptions({detached: true});
``

[Changelog][history]

[history]: https://github.com/Intervox/node-webp/blob/latest/History.md