@itk-wasm/htj2k


> Wasm-SIMD accelerated decoding and encoding of High-throughput JPEG2000 (HTJ2K) images.

👨‍💻 Live API Demo ✨

🕮 Documentation 📚

Installation

``sh
npm install @itk-wasm/htj2k
`

Usage

$3

Import:

`js
import {
decode,
encode,
setPipelinesBaseUrl,
getPipelinesBaseUrl,
setPipelineWorkerUrl,
getPipelineWorkerUrl,
} from "@itk-wasm/htj2k"
`

#### decode

Decode a High Throughput JPEG2000 codestream and generate an ITK Image

`ts
async function decode(
webWorker: null | Worker,
codestream: Uint8Array,
options: DecodeOptions = {}
) : Promise
`

| Parameter | Type | Description |
| :----------: | :----------: | :--------------------- |
| codestream | Uint8Array | Input HTJ2K codestream |

DecodeOptions interface:

| Property | Type | Description |
| :------------------: | :-------: | :----------------------------------------------------------------- |
| decompositionLevel | number | Decomposition level to decode. 0 is the highest resolution. |
| informationOnly | boolean | Only read metadata for the image but do not decode the pixel data. |

DecodeResult interface:

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

#### encode

Encode an ITK Image into a High Throughput JPEG2000 codestream

`ts
async function encode(
webWorker: null | Worker,
image: Image,
options: EncodeOptions = {}
) : Promise
`

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

EncodeOptions interface:

| Property | Type | Description |
| :----------------: | :--------: | :-------------------------------------------------------------------------------------- |
| decompositions | number | Number of wavelet decompositions |
| notReversible | boolean | Lossy and not reversible, i.e. not lossless, encoding |
| quantizationStep | number | Quantization step size for lossy compression. Ignored unless not reversible is enabled. |
| progressionOrder | number | Progression order. 0 = LRCP, 1 = RLCP, 2 = RPCL, 3 = PCRL, 4 = CPRL |
| tileSize | number[] | Tile size |
| tileOffset | number[] | Tile offset |
| blockDimensions | number[] | Block dimensions |

EncodeResult interface:

| Property | Type | Description |
| :-----------: | :----------: | :----------------------------- |
| webWorker | Worker | WebWorker used for computation |
| output | Uint8Array | Output binary HTJ2K codestream |

#### 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
`

#### setPipelineWorkerUrl

Set base URL for the itk-wasm pipeline worker script when vendored.

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

#### getPipelineWorkerUrl

Get base URL for the itk-wasm pipeline worker script when vendored.

`ts
function getPipelineWorkerUrl() : string | URL
`

$3

Import:

`js
import {
decodeNode,
encodeNode,
setPipelinesBaseUrl,
getPipelinesBaseUrl,
setPipelineWorkerUrl,
getPipelineWorkerUrl,
} from "@itk-wasm/htj2k"
`

#### decodeNode

Decode a High Throughput JPEG2000 codestream and generate an ITK Image

`ts
async function decodeNode(
codestream: Uint8Array,
options: DecodeOptions = {}
) : Promise
`

| Parameter | Type | Description |
| :----------: | :----------: | :--------------------- |
| codestream | Uint8Array | Input HTJ2K codestream |

DecodeNodeOptions interface:

| Property | Type | Description |
| :------------------: | :-------: | :----------------------------------------------------------------- |
| decompositionLevel | number | Decomposition level to decode. 0 is the highest resolution. |
| informationOnly | boolean | Only read metadata for the image but do not decode the pixel data. |

DecodeNodeResult interface:

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

#### encodeNode

Encode an ITK Image into a High Throughput JPEG2000 codestream

`ts
async function encodeNode(
image: Image,
options: EncodeOptions = {}
) : Promise
`

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

EncodeNodeOptions interface:

| Property | Type | Description |
| :----------------: | :--------: | :-------------------------------------------------------------------------------------- |
| decompositions | number | Number of wavelet decompositions |
| notReversible | boolean | Lossy and not reversible, i.e. not lossless, encoding |
| quantizationStep | number | Quantization step size for lossy compression. Ignored unless not reversible is enabled. |
| progressionOrder | number | Progression order. 0 = LRCP, 1 = RLCP, 2 = RPCL, 3 = PCRL, 4 = CPRL |
| tileSize | number[] | Tile size |
| tileOffset | number[] | Tile offset |
| blockDimensions | number[] | Block dimensions |

EncodeNodeResult interface:

| Property | Type | Description |
| :------: | :----------: | :----------------------------- |
| output` | Uint8Array | Output binary HTJ2K codestream |