gifencoder
Streaming server-side animated (and non-animated) gif generation for node.js
Installation
This module is installed via npm:
$ npm install gifencoder
Streaming API - Duplex Piping with Writes
You can also stream writes of pixel data (or canvas contexts) to the encoder:
const GIFEncoder = require('gifencoder');
const encoder = new GIFEncoder(854, 480);
const pngFileStream = require('png-file-stream');
const fs = require('fs');
const stream = pngFileStream('test/**/frame?.png')
.pipe(encoder.createWriteStream({ repeat: -1, delay: 500, quality: 10 }))
.pipe(fs.createWriteStream('myanimated.gif'));
stream.on('finish', function () {
// Process generated GIF
});
// Alternately, you can wrap the "finish" event in a Promise
await new Promise((resolve, reject) => {
stream.on('finish', resolve);
stream.on('error', reject);
});
NB: The chunks that get emitted by your read stream must either by a 1-dimensional bitmap of RGBA
data (either an array or Buffer), or a canvas 2D context
.
Example: Streaming API - Reads
You can also use a streaming API to receive data:
const GIFEncoder = require('gifencoder');
const { createCanvas } = require('canvas');
const fs = require('fs');
const encoder = new GIFEncoder(320, 240);
// stream the results as they are available into myanimated.gif
encoder.createReadStream().pipe(fs.createWriteStream('myanimated.gif'));
encoder.start();
encoder.setRepeat(0); // 0 for repeat, -1 for no-repeat
encoder.setDelay(500); // frame delay in ms
encoder.setQuality(10); // image quality. 10 is default.
// use node-canvas
const canvas = createCanvas(320, 240);
const ctx = canvas.getContext('2d');
// red rectangle
ctx.fillStyle = '#ff0000';
ctx.fillRect(0, 0, 320, 240);
encoder.addFrame(ctx);
// green rectangle
ctx.fillStyle = '#00ff00';
ctx.fillRect(0, 0, 320, 240);
encoder.addFrame(ctx);
// blue rectangle
ctx.fillStyle = '#0000ff';
ctx.fillRect(0, 0, 320, 240);
encoder.addFrame(ctx);
encoder.finish();
The above code will generate the following animated GIF:
Contributing
gifencoder is an OPEN Open Source Project. This means that:
Individuals making significant and valuable contributions are given commit-access to the project to contribute as they see fit. This project is more like an open wiki than a standard guarded open source project.
See the CONTRIBUTING.md file for more details.
Contributors
gifencoder is only possible due to the excellent work of the following contributors:
Kevin Weiner | [email protected] |
---|---|
Thibault Imbert | http://www.bytearray.org/ |
Eugene Ware | GitHub/eugeneware |
Raine Virta | GitHub/raine |
Paul Ochoa | GitHub/rochoa |
Heikki Pora | GitHub/heikkipora |