sharp-ico

ICO encoder and decoder for sharp base on ico-endec (for encode) and decode-ico (for decode).

Install

npm install sharp-ico

Usage

Create instances of sharp from an ICO image

ico.sharpsFromIco(input, options?, resolveWithObject?)

• input (string | Buffer) - A String containing the filesystem path to an ICO image file, or a Buffer containing ICO image data.
• options Object (optional) - sharp constructor options.
• resolveWithObject boolean (optional) - Return an array of Object containing image (instance of sharp) property and decoding info instead of only instance of sharp. Default by false.

Returns Sharp[] | ImageData[] - Return an array of instance of sharp or Object containing image (instance of sharp) property and decoding info.

const ico = require("sharp-ico");

ico
  .sharpsFromIco("input.ico", {
    // sharp constructor options
  }) // returns an array of instance of sharp
  .forEach(async (icon, index) => {
    icon.toFile(`output-${index}.png`);

    // Or
    const metadata = await icon.metadata();
    icon.toFile(`output-${metadata.width}x${metadata.height}.png`);
  });

// Set the third option to `true`, will return objects with decoding info
ico
  .sharpsFromIco("input.ico", null, true)
  .forEach((icon) => {
    icon.image.toFile(`output-${icon.width}x${icon.height}.png`);
  });

Write an ICO file

ico.sharpsToIco(icons, fileOut, options?)

• icons Sharp[] - An array of instance of sharp.
• fileOut string - The path to write the image data to.
• options Object (optional)
  • sizes (number[] | "default") - Array of sizes to use when resizing. "default" equal to [256, 128, 64, 48, 32, 24, 16].
  • resizeOptions Object (optional) - sharp resize options.

Returns Promise<Object> - Resolve with an Object containing size, width, height properties.

const sharp = require("sharp");
const ico= require("sharp-ico");
const bmp = require("sharp-bmp"); // if need to write bmp icons

ico
  .sharpsToIco(
    [
      sharp("input-256x256.png"),
      bmp.sharpFromBmp("input-64x64.bmp"),
      sharp("input-32x32.png"),
      // more sizes...
    ],
    "output.ico"
  )
  .then((info) => {
    console.log(info); // { size, width, height }
  })
  .catch((err) => {
    console.error(err);
  });

// sizes options
ico
  .sharpsToIco(
    [
      sharp("input-256x256.png")
    ],
    "output.ico",
    {
      sizes: [64, 32, 24],
      // sizes: "default", // equal to [256, 128, 64, 48, 32, 24, 16]
      resizeOptions: {}, // sharp resize optinos
    }
  ); // will output a 64x64 ico image (with 32x32 and 24x24 sizes)

Decode ICO

ico.decode(buffer)

• buffer Buffer - A Buffer containing ICO image data.

Returns Object[] - Return an array of Object contains the following decoding info:

• width number - The width of the image, in pixels.
• height number - The height of the image, in pixels.
• type string - The type of image, will be one of bmp or png.
• data Uint8Array - The data of the image, format depends on type, see below.
• bpp number - The color depth of the image as the number of bits used per pixel.
• hotspot null | { x: number, y: number } - If the image is a cursor (.cur), this is the hotspot.

The format of the data parameter depends on the type of image. When the image is of type bmp, the data array will hold raw pixel data in the RGBA order, with integer values between 0 and 255 (included). When the type is png, the array will be png data.

const fs = require("fs");
const sharp = require("sharp");
const ico = require("sharp-ico");

const buffer = fs.readFileSync("input.ico");
const icons = ico.decode(buffer);

icons.forEach((icon) => {
  const image = icon.type === "png"
    ? sharp(icon.data)
    : sharp(icon.data, {
        raw: {
          width: icon.width,
          height: icon.height,
          channels: 4,
        },
      });
  image.toFile(`output-${icon.width}x${icon.height}.png`);
});

Encode ICO

ico.encode(bufferList)

• bufferList Buffer[] - An array of Buffer containing PNG or BMP image data.

Returns Buffer - Return a buffer containing ICO image data.

const fs = require("fs");
const sharp = require("sharp");
const ico = require("sharp-ico");
const bmp = require("sharp-bmp"); // if need to write bmp icons

(async () => {
  const icons = [
    sharp("input-256x256.png"),
    bmp.sharpFromBmp("input-64x64.bmp"),
    sharp("input-32x32.png"),
  ];
  const bufferList = [];
  for (let i = 0; i < icons.length; i++) {
    const buffer = await icons[i].toFormat("png").toBuffer();
    bufferList.push(buffer);
  }
  const icoBuffer = ico.encode(bufferList);
  fs.writeFileSync("output.ico", icoBuffer);

  console.log(icoBuffer.length); // size of output.ico
})();

Change Log

0.1.1

• sharpsToIco support sizes option

0.1.5

• Use decode-ico instead of ico-endec for decoding to support transparent bmp icons.