An Image is the N-dimensional image data structure for itk-wasm.

Image is a JavaScript object with the following properties:

  • imageType: The ImageType for this image.

  • name: An optional name string that describes this image.

  • origin An Array with length imageType.dimension that describes the location of the center of the lower left pixel in physical units.

  • spacing: An Array with length dimension that describes the spacing between pixel in physical units.

  • direction: A dimension by dimension length Float64Array in column-major order, that describes the orientation of the image at its origin The orientation of each axis are the orthonormal columns.

  • size: An Array with length dimension that contains the number of pixels along dimension.

  • data: A TypedArray containing the pixel buffer data.

  • metadata: A Map of string keys to values that could be strings, string arrays, numbers, number arrays, or arrays of number arrays providing additional metadata for the image.

For more information, see the description of an itk::Image in the ITK Software Guide.

Note that the origin, spacing, direction, and size are indexed with an x, y, z convention ordering. This is the reverse indexing convention relative to other libraries such as TensorFlow.js. To generate a TensorFlow tensor from an Image, image:

const tensor = tf.tensor(, image.size.reverse())

To visualize an Image with vtk.js use convertItkToVtkImage from vtk.js/Sources/Common/DataModel/ITKHelper.