@itk-wasm/compare-images NPM

@itk-wasm/compare-images

Compare images with a tolerance for regression testing.

Installation

npm install @itk-wasm/compare-images

Usage

Browser interface

Import:

import {
  compareImages,
  setPipelinesBaseUrl,
  getPipelinesBaseUrl,
} from "@itk-wasm/compare-images"

compareImages

Compare images with a tolerance for regression testing.

async function compareImages(
  testImage: Image,
  options: CompareImagesOptions = { baselineImages: [] as Image[], }
) : Promise<CompareImagesResult>

Parameter	Type	Description
`testImage`	Image	The input test image

CompareImagesOptions interface:

Property	Type	Description
`baselineImages`	Image[]	Baseline images compare against
`differenceThreshold`	number	Intensity difference for pixels to be considered different.
`radiusTolerance`	number	Radius of the neighborhood around a pixel to search for similar intensity values.
`numberOfPixelsTolerance`	number	Number of pixels that can be different before the test fails.
`ignoreBoundaryPixels`	boolean	Ignore boundary pixels. Useful when resampling may have introduced difference pixel values along the image edge.
`webWorker`	null or Worker or boolean	WebWorker for computation. Set to null to create a new worker. Or, pass an existing worker. Or, set to `false` to run in the current thread / worker.
`noCopy`	boolean	When SharedArrayBuffer's are not available, do not copy inputs.

CompareImagesResult interface:

Property	Type	Description
`metrics`	JsonCompatible	Metrics for the baseline with the fewest number of pixels outside the tolerances.
`differenceImage`	Image	Absolute difference image
`differenceUchar2dImage`	Image	Unsigned char, 2D difference image for rendering
`webWorker`	Worker	WebWorker used for computation.

setPipelinesBaseUrl

Set base URL for WebAssembly assets when vendored.

function setPipelinesBaseUrl(
  baseUrl: string | URL
) : void

getPipelinesBaseUrl

Get base URL for WebAssembly assets when vendored.

function getPipelinesBaseUrl() : string | URL

Node interface

Import:

import {
  compareImagesNode,
} from "@itk-wasm/compare-images"

compareImagesNode

Compare images with a tolerance for regression testing.

async function compareImagesNode(
  testImage: Image,
  options: CompareImagesOptions = { baselineImages: [] as Image[], }
) : Promise<CompareImagesNodeResult>

Parameter	Type	Description
`testImage`	Image	The input test image

CompareImagesNodeOptions interface:

Property	Type	Description
`baselineImages`	Image[]	Baseline images compare against
`differenceThreshold`	number	Intensity difference for pixels to be considered different.
`radiusTolerance`	number	Radius of the neighborhood around a pixel to search for similar intensity values.
`numberOfPixelsTolerance`	number	Number of pixels that can be different before the test fails.
`ignoreBoundaryPixels`	boolean	Ignore boundary pixels. Useful when resampling may have introduced difference pixel values along the image edge.

CompareImagesNodeResult interface:

Property	Type	Description
`metrics`	JsonCompatible	Metrics for the baseline with the fewest number of pixels outside the tolerances.
`differenceImage`	Image	Absolute difference image
`differenceUchar2dImage`	Image	Unsigned char, 2D difference image for rendering