@itk-wasm/compare-images

Compare images with a tolerance for regression testing.

👨‍💻 Live API Demo ✨

🕮 Documentation 📚

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 |