Node WebP

Prerequisites

• CMake >= 3.21.0

Installation

npm install giovannicalo/node-webp

Not yet published to NPM. This will install it from GitHub.

Usage

Decoding

const { promises: { readFile, writeFile } } = require("fs");

const { Format, decode } = require("webp");

(async () => {
    const webp = await readFile("foo.webp");
    const rgba = await decode(webp, Format.rgba);
    console.log(rgba);
    // {
    //   data: Uint8ClampedArray(8294400) [...],
    //   format: 0,
    //   height: 1080,
    //   width: 1920
    // }
    await writeFile("foo.rgba", rgba.data);
    const yuv = await decode(webp, Format.yuv);
    console.log(yuv);
    // {
    //   data: Uint8ClampedArray(3110400) [...],
    //   format: 1,
    //   height: 1080,
    //   width: 1920
    // }
    await writeFile("foo.yuv", yuv.data);
})();

Encoding

const { promises: { readFile, writeFile } } = require("fs");

const { Format, encode } = require("webp");

(async () => {
    const rgba = {
        data: await readFile("foo.rgba"),
        format: Format.rgba,
        height: 1080,
        width: 1920
    };
    const webp = await encode(rgba, 90);
    console.log(webp);
    // <Buffer ...>
    await writeFile("foo.webp", webp);
})();

API

Format.rgba = 0

Standard RGBA format.

Format.yuv = 1

YUV I420 format, currently supports only decoding. Smaller and faster than RGBA, but less straightforward. When decoding, if the source WebP has odd dimensions, they will be rounded up to the nearest even number.

decode(data: Buffer, format: Format = Format.rgba): Promise<Image>

Decodes the WebP image stored in the data Buffer as format, which can be either Format.rgba or Format.yuv.

Returns a promise resolving to an object with data, height, format and width properties.

encode(image: Image, quality: number = 90): Promise<Buffer>

Encodes a raw image as WebP with the given quality. image must be an object with data, height, format and width properties. image.format currently has to be Format.rgba.

Returns a promise resolving to a Buffer.