images-to-deflate-tiff v0.2.1

images-to-deflate-tiff

Generate a deflate-compressed tiff file from one or more images.

Demo

Installation

npm i images-to-deflate-tiff

Usage

import { imagesToDeflateTiff, imagesToZlibTiff, imagesToUncompressedTiff } from "images-to-deflate-tiff";

const canvas = document.querySelector("canvas");
const images = [canvas.getContext("2d").getImageData(0, 0, canvas.width, canvas.height)];

// these option values are defaults.
const options = {
  littleEndian: true,
  alpha: true,
  xResolution: 72,
  yResolution: 72,
  resolutionUnit: 2, // 1 (unspecified) | 2 (inch) | 3 (cm)
};

// Compression: 1 (No compression)
const uncompressedTiffArrayBuffer = await imagesToUncompressedTiff(images, options);

// Compression: 32946 (Deflate)
const deflateTiffArrayBuffer = await imagesToDeflateTiff(images, options);

// Compression: 8 (Zlib = Deflate)
const zlibTiffArrayBuffer = await imagesToZlibTiff(images, options);

The argument is an array of ImageData (or object with data, width, height and colorSpace: "srgb" properties).

See https://developer.mozilla.org/docs/Web/API/ImageData

import { imagesToZlibTiff } from "images-to-deflate-tiff";

async function imageDataFromImageFile(file: File): Promise<ImageData> {
  const bitmap = await createImageBitmap(file);
  const canvas = document.createElement("canvas");
  canvas.width = bitmap.width;
  canvas.height = bitmap.height;
  const context = canvas.getContext("2d");
  context.drawImage(bitmap, 0, 0);
  const image = context.getImageData(0, 0, canvas.width, canvas.height);
  bitmap.close();
  return image;
}

async function tiffFileFromImageFiles(files: FileList): Promise<File> {
  const images = await Promise.all(Array.from(files, imageDataFromImageFile));
  const tiffArrayBuffer = await imagesToZlibTiff(images);
  return new File([tiffArrayBuffer], "file.tiff", { type: "image/tiff" });
}