itk-wasm in a Node.js application¶

An itk-convert command line interface (CLI) example demonstrates how to use itk-wasm in a Node.js application. Find the full example in the itk-wasm/examples/node-js directory of the GitHub repository.

This example assumes you are creating a Node.js package. If you do not already have a package.json file, create one, first.

Add itk-wasm to your project’s dependencies:

npm install --save itk-wasm @itk-wasm/image-io @itk-wasm/mesh-io

This adds itk-wasm and itk-wasm IO packages to the dependencies section of your package.json file:

{
  "name": "itk-convert",
  "version": "3.0.0",
  "description": "Convert image or mesh files from one format to another.",
  "type": "module",
[...]
  "dependencies": {
    "@itk-wasm/image-io": "^1.1.0",
    "@itk-wasm/mesh-io": "^1.1.0",
    "commander": "^11.1.0",
    "itk-wasm": "^1.0.0-b.162"
  }
}

Next, call functions like readImageNode or writeImageNode.

For example,

import { readImageNode, writeImageNode } from '@itk-wasm/image-io'
import { readMeshNode, writeMeshNode, extensionToMeshIo } from '@itk-wasm/mesh-io'
import { getFileExtension } from 'itk-wasm'

const extension = getFileExtension(inputFile).toLowerCase()
const isMesh = extensionToMeshIo.has(extension)

try {
  if (isMesh) {
    const mesh = await readMeshNode(inputFile)
    await writeMeshNode(mesh, outputFile)
  } else {
    const image = await readImageNode(inputFile)
    await writeImageNode(image, outputFile)
  }
} catch (error) {
  console.error('Error during conversion:\n')
  console.error(error)
}