@itk-wasm/downsample


> Pipelines for downsampling images.

💻 Live API Demo ✨

🕮 Documentation 📚

Installation

``sh
npm install @itk-wasm/downsample
`

Usage

$3

Import:

`js
import {
downsampleBinShrink,
downsampleLabelImage,
downsampleSigma,
downsample,
gaussianKernelRadius,
setPipelinesBaseUrl,
getPipelinesBaseUrl,
} from "@itk-wasm/downsample"
`

#### downsampleBinShrink

Apply local averaging and subsample the input image.

`ts
async function downsampleBinShrink(
input: Image,
options: DownsampleBinShrinkOptions = { shrinkFactors: [] as number[], }
) : Promise
`

| Parameter | Type | Description |
| :-------: | :-----: | :---------- |
| input | Image | Input image |

DownsampleBinShrinkOptions interface:

| Property | Type | Description |
| :---------------: | :-------------------------: | :---------------------------------------------------------------------------------------------------------------------------------------------------- |
| shrinkFactors | number[] | Shrink factors |
| informationOnly | boolean | Generate output image information only. Do not process pixels. |
| 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. |

DownsampleBinShrinkResult interface:

| Property | Type | Description |
| :-----------: | :------: | :------------------------------ |
| downsampled | Image | Output downsampled image |
| webWorker | Worker | WebWorker used for computation. |

#### downsampleLabelImage

Apply a smoothing anti-alias filter and subsample the input image.

`ts
async function downsampleLabelImage(
input: Image,
options: DownsampleLabelImageOptions = { shrinkFactors: [] as number[], }
) : Promise
`

| Parameter | Type | Description |
| :-------: | :-----: | :---------- |
| input | Image | Input image |

DownsampleLabelImageOptions interface:

| Property | Type | Description |
| :-------------: | :-------------------------: | :---------------------------------------------------------------------------------------------------------------------------------------------------- |
| shrinkFactors | number[] | Shrink factors |
| cropRadius | number[] | Optional crop radius in pixel units. |
| 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. |

DownsampleLabelImageResult interface:

| Property | Type | Description |
| :-----------: | :------: | :------------------------------ |
| downsampled | Image | Output downsampled image |
| webWorker | Worker | WebWorker used for computation. |

#### downsampleSigma

Compute gaussian kernel sigma values in pixel units for downsampling.

`ts
async function downsampleSigma(
options: DownsampleSigmaOptions = { shrinkFactors: [] as number[], }
) : Promise
`

| Parameter | Type | Description |
| :-------: | :--: | :---------- |

DownsampleSigmaOptions interface:

| Property | Type | Description |
| :-------------: | :-------------------------: | :---------------------------------------------------------------------------------------------------------------------------------------------------- |
| shrinkFactors | number[] | Shrink factors |
| 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. |

DownsampleSigmaResult interface:

| Property | Type | Description |
| :---------: | :--------------: | :------------------------------ |
| sigma | JsonCompatible | Output sigmas in pixel units. |
| webWorker | Worker | WebWorker used for computation. |

#### downsample

Apply a smoothing anti-alias filter and subsample the input image.

`ts
async function downsample(
input: Image,
options: DownsampleOptions = { shrinkFactors: [] as number[], }
) : Promise
`

| Parameter | Type | Description |
| :-------: | :-----: | :---------- |
| input | Image | Input image |

DownsampleOptions interface:

| Property | Type | Description |
| :-------------: | :-------------------------: | :---------------------------------------------------------------------------------------------------------------------------------------------------- |
| shrinkFactors | number[] | Shrink factors |
| cropRadius | number[] | Optional crop radius in pixel units. |
| 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. |

DownsampleResult interface:

| Property | Type | Description |
| :-----------: | :------: | :------------------------------ |
| downsampled | Image | Output downsampled image |
| webWorker | Worker | WebWorker used for computation. |

#### gaussianKernelRadius

Radius in pixels required for effective discrete gaussian filtering.

`ts
async function gaussianKernelRadius(
options: GaussianKernelRadiusOptions = { size: [] as number[], sigma: [{}, ], }
) : Promise
`

| Parameter | Type | Description |
| :-------: | :--: | :---------- |

GaussianKernelRadiusOptions interface:

| Property | Type | Description |
| :--------------: | :-------------------------: | :---------------------------------------------------------------------------------------------------------------------------------------------------- |
| size | number[] | Size in pixels |
| sigma | number[] | Sigma in pixel units |
| maxKernelWidth | number | Maximum kernel width in pixels. |
| maxKernelError | number | Maximum kernel error. |
| 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. |

GaussianKernelRadiusResult interface:

| Property | Type | Description |
| :---------: | :--------------: | :------------------------------ |
| radius | JsonCompatible | Output kernel radius. |
| webWorker | Worker | WebWorker used for computation. |

#### setPipelinesBaseUrl

Set base URL for WebAssembly assets when vendored.

`ts
function setPipelinesBaseUrl(
baseUrl: string | URL
) : void
`

#### getPipelinesBaseUrl

Get base URL for WebAssembly assets when vendored.

`ts
function getPipelinesBaseUrl() : string | URL
`

$3

Import:

`js
import {
downsampleBinShrinkNode,
downsampleLabelImageNode,
downsampleSigmaNode,
downsampleNode,
gaussianKernelRadiusNode,
} from "@itk-wasm/downsample"
`

#### downsampleBinShrinkNode

Apply local averaging and subsample the input image.

`ts
async function downsampleBinShrinkNode(
input: Image,
options: DownsampleBinShrinkNodeOptions = { shrinkFactors: [] as number[], }
) : Promise
`

| Parameter | Type | Description |
| :-------: | :-----: | :---------- |
| input | Image | Input image |

DownsampleBinShrinkNodeOptions interface:

| Property | Type | Description |
| :---------------: | :--------: | :------------------------------------------------------------- |
| shrinkFactors | number[] | Shrink factors |
| informationOnly | boolean | Generate output image information only. Do not process pixels. |

DownsampleBinShrinkNodeResult interface:

| Property | Type | Description |
| :-----------: | :-----: | :----------------------- |
| downsampled | Image | Output downsampled image |

#### downsampleLabelImageNode

Apply a smoothing anti-alias filter and subsample the input image.

`ts
async function downsampleLabelImageNode(
input: Image,
options: DownsampleLabelImageNodeOptions = { shrinkFactors: [] as number[], }
) : Promise
`

| Parameter | Type | Description |
| :-------: | :-----: | :---------- |
| input | Image | Input image |

DownsampleLabelImageNodeOptions interface:

| Property | Type | Description |
| :-------------: | :--------: | :----------------------------------- |
| shrinkFactors | number[] | Shrink factors |
| cropRadius | number[] | Optional crop radius in pixel units. |

DownsampleLabelImageNodeResult interface:

| Property | Type | Description |
| :-----------: | :-----: | :----------------------- |
| downsampled | Image | Output downsampled image |

#### downsampleSigmaNode

Compute gaussian kernel sigma values in pixel units for downsampling.

`ts
async function downsampleSigmaNode(
options: DownsampleSigmaNodeOptions = { shrinkFactors: [] as number[], }
) : Promise
`

| Parameter | Type | Description |
| :-------: | :--: | :---------- |

DownsampleSigmaNodeOptions interface:

| Property | Type | Description |
| :-------------: | :--------: | :------------- |
| shrinkFactors | number[] | Shrink factors |

DownsampleSigmaNodeResult interface:

| Property | Type | Description |
| :------: | :--------------: | :---------------------------- |
| sigma | JsonCompatible | Output sigmas in pixel units. |

#### downsampleNode

Apply a smoothing anti-alias filter and subsample the input image.

`ts
async function downsampleNode(
input: Image,
options: DownsampleNodeOptions = { shrinkFactors: [] as number[], }
) : Promise
`

| Parameter | Type | Description |
| :-------: | :-----: | :---------- |
| input | Image | Input image |

DownsampleNodeOptions interface:

| Property | Type | Description |
| :-------------: | :--------: | :----------------------------------- |
| shrinkFactors | number[] | Shrink factors |
| cropRadius | number[] | Optional crop radius in pixel units. |

DownsampleNodeResult interface:

| Property | Type | Description |
| :-----------: | :-----: | :----------------------- |
| downsampled | Image | Output downsampled image |

#### gaussianKernelRadiusNode

Radius in pixels required for effective discrete gaussian filtering.

`ts
async function gaussianKernelRadiusNode(
options: GaussianKernelRadiusNodeOptions = { size: [] as number[], sigma: [{}, ], }
) : Promise
`

| Parameter | Type | Description |
| :-------: | :--: | :---------- |

GaussianKernelRadiusNodeOptions interface:

| Property | Type | Description |
| :--------------: | :--------: | :------------------------------ |
| size | number[] | Size in pixels |
| sigma | number[] | Sigma in pixel units |
| maxKernelWidth | number | Maximum kernel width in pixels. |
| maxKernelError | number | Maximum kernel error. |

GaussianKernelRadiusNodeResult interface:

| Property | Type | Description |
| :------: | :--------------: | :-------------------- |
| radius` | JsonCompatible | Output kernel radius. |