PureJsImage · JPEG XL

JPEG XL native precision and channels

Inspect actual integer and float bit patterns, alpha, channel grids and color metadata. Export native samples separately from a mapped display.

These tools use the current repository build. Repository functionality may be newer than the npm release. Static lossy encoding is qualified; lossy animation remains Experimental.

Open

Local JPEG XL

Sample planeMap this value to display whiteSample XSample Y

Plane preview maps 0 to black and your white value to white. It does not change stored samples or apply an ICC profile.

Generated samples: repository MIT fixtures. File limit 64 MiB. Previews at most four megapixels. Cancellation discards the worker session; retry reopens the same file.

Try a sample or open a local file.

Timing, metadata and numeric evidence

No file opened.

Browser API

import { openJpegXlSequence, jpegXlNativeUnsignedPlanes } from 'purejsimage/jpegxl'
const sequence = await openJpegXlSequence(file)
try {
  for await (const layer of sequence.layers()) {
    const bits = jpegXlNativeUnsignedPlanes(layer)
    console.log(layer.header, bits[0]?.[0])
    break
  }
} finally { await sequence.close() }

Run codec work in a worker. The example uses the same public APIs as this tool. The display is a scalar plane mapping. Native export supports preservable static Modular integer/binary32 layouts with orientation 1 and default luminance metadata. Additional metadata, custom chromaticities and unsupported writer combinations fail explicitly. A canvas does not prove sample precision.

Actual stages and source reads

Browser API