Lens Docs

Appearance

Resample Filter API ​

Resample filter uses weighting functions for calculating pixel color weights, depending on distance from EWA ellipse center in EWA resampling.

ResampleFilter interface ​

ts
interface ResampleFilter {
  getWorkingSupport(): number;
  getWeight(x: number): number;
}

Methods ​

getWorkingSupport() ​

  • Returns: number

Returns filter practical working support.

getWeight() ​

  • Param: x: number
  • Returns: number

Returns color weight at given distance from EWA ellipse center.

Type guard ​

isResampleFilter function checks if given argument is ResampleFilter and can be used as type guard.

ResampleFilterPreset interface ​

ResampleFilterPreset interface is object with predefined resample filter settings.

ts
interface ResampleFilterPreset {
  filterFunctionFactory: WeightingFunctionName | string;
  filterFunctionFactoryArgs: number[];
  windowFunctionFactory: WeightingFunctionName | string;
  windowFunctionFactoryArgs: number[];
  support: number;
  scale: number;
  blur?: number;
  windowSupport?: number;
}

Properties ​

filterFunctionFactory ​

  • Type: WeightingFunctionFactoryName | string

Name of weighting function factory. Internally, factory will be supplied by filterFunctionFactoryArgs to produce filter function, which is responsible for pixel color weights inside EWA ellipse.

filterFunctionFactoryArgs ​

  • Type: number[]

Array of arguments, which will be passed to corresponding WeightingFunctionFactory.

windowFunctionFactory ​

  • Type: WeightingFunctionFactoryName | string

Name of weighting function factory. Internally, factory will be supplied by filterFunctionFactoryArgs to produce window function, which is responsible for modulation of filter function.

windowFunctionFactoryArgs ​

  • Type: number[]

Array of arguments, which will be passed to corresponding WeightingFunctionFactory.

support ​

  • Type: number

Filter support value.

scale ​

  • Type: number

Filter scale value.

blur ​

  • Type: number

Optional filter blur value. Defaults to 1.

windowSupport ​

  • Type: number

Optional filter window support value. By default, equals filter support.

Type guard ​

isResampleFilterPreset checks if given argument is ResampleFilterPreset and can be used as type guard.

ResampleFilterPresetsPool interface ​

Pool of built-in filter presets. Keys are FilterName enum values.

ts
interface ResampleFilterPresetsPoolKeyMap {
  [FilterName.ROBIDOUX]: ResampleFilterPreset;
  [FilterName.ROBIDOUX_SHARP]: ResampleFilterPreset;
  [FilterName.BOX]: ResampleFilterPreset;
  [key: FilterName | string]: ResampleFilterPreset;
}

type ResampleFilterPresetsPool = Pool<
  ResampleFilterPreset,
  ResampleFilterPresetsPoolKeyMap
>;