canvas-screenshot

canvas-screenshot

A one trick pony package to download an image from a canvas.

Installation

npm install canvas-screenshot

Usage

import canvasScreenshot from "canvas-screenshot";
import canvasContext from "canvas-context";

// Create
const { context, canvas } = canvasContext("2d", {
  width: 100,
  height: 100,
});

// Draw
context.fillStyle = "salmon";
context.fillRect(40, 40, 20, 20);

// Export
const button = document.createElement("button");
button.addEventListener("click", () => {
  canvasScreenshot(canvas);
});

API

Modules

canvasScreenshot

Typedefs

CanvasScreenshotOptions : object

Options for canvas screenshot. All optional.

canvasScreenshot

canvasScreenshot(canvas, [options]) ⇒ string | Promise.<Blob> ⏏

Take a screenshot. Setting options.useBlob to true will consequently make the module async and return the latter.

Kind: Exported function Returns: string | Promise.<Blob> - A DOMString or a Promise resolving with a Blob.

Type is inferred from the filename extension:

• png for "image/png" (default)
• jpg/jpeg for "image/jpeg"
• webp for "image/webp"

Param	Type	Default	Description
canvas	HTMLCanvasElement		The canvas element
[options]	CanvasScreenshotOptions	{}

CanvasScreenshotOptions : object

Options for canvas screenshot. All optional.

Kind: global typedef Properties

Name	Type	Default	Description
[filename]	string	"Screen Shot YYYY-MM-DD at HH.MM.SS.png"	File name.
[quality]	number	1	Quality between 0 and 1.
[useBlob]	boolean		Use canvas.toBlob.
[download]	boolean	true	Automatically download the screenshot.

License

MIT. See license file.

Changelog

4.2.0 (2024-01-22)

Features

• add support for image/webp (b645d38)