node-webpinfo

Node.js Stream based WebP Container Parser.

node-webpinfo Example	webpinfo (libwebp)

Sponsor

• Vingle - Vingle, Very Community. Love the things that you love. - We're hiring!

Install

$ npm install webpinfo

Supported WebP Formats

• Simple File Format (Lossy)
• Simple File Format (Lossless)
• Extended File Format (e.g. Animated WebP)

Supported WebP Chunks

• VP8
• VP8L
• VP8X
• ANIM
• ANMF
• ALPH
• ICCP
• EXIF
• XMP

Usage

Promise interface

import { WebPInfo } from "webpinfo";

// local file path
const info = await WebPInfo.from("/some/local/file/path.webp");
// url
const info = await WebPInfo.from("https://example.com/some/file/path.webp");
// buffer
const info = await WebPInfo.from(buf);
// readable stream
const info = await WebPInfo.from(fs.createReadStream(path));
console.log("INFO: ", info);

Stream interface

import * as http from "http";
import { WebPInfo } from "webpinfo";

http.get("http://www.gstatic.com/webp/gallery/1.webp", (res) => {
  if (res.statusCode !== 200) {
    console.log("unexpected status code: ", res.statusCode);
    return;
  }

  res.pipe(new WebPInfo())
    .on("error", (e) => console.log("error", e))
    .on("riff", (riff) => console.log("riff", riff))
    .on("chunk", (chunk) => console.log("chunk", chunk))
    .on("format", (format) => console.log("format", format));
});

API

Please refer detailed type definitions on src/webpinfo.ts.

WebPInfo => WritableStream

Basically WebPInfo is WritableStream.

WebPInfo.from(input: string | Buffer | ReadableStream) => Promise<WebP>

Parse WebPInfo from given input. Input can be local file path, url, Buffer, or Readable Stream.

WebPInfo.isAnimated(input: string | Buffer | ReadableStream) => Promise<boolean>

Return true if given input contains any animation frame.

WebPInfo.isLossless(input: string | Buffer | ReadableStream) => Promise<boolean>

Return true if given buffer contains VP8L chunk.

Stream Events

riff

• Event Payload: RIFFContainer

emitted after parsing riff header.

chunk

• Event Payload: WebPChunk

emitted after parsing WebP chunk

format

• Event Payload: WebP

emitted after all WebP chunks have parsed

Related

• mooyoul/is-webp-extended - Extended version of is-webp package which supports Animated WebP. Compatible with Browser environment (e.g. File, ArrayBuffer)

Changelog

See CHANGELOG.

Debugging

Set DEBUG environment variable to webpinfo. You will be able to see debug messages on your console.

$ env DEBUG='webpinfo' node your-app.js

Testing

$ npm run test

... OR

$ npm run lint # Check lint
$ npm run coverage # Run test & generate code coverage report

Build

$ npm run build

License

MIT

See full license on mooyoul.mit-license.org