JASCO JWS

Status: Supported (scoped) · Vendor: JASCO · Extensions: .jws

JWS is the native binary format written by JASCO Spectra Manager for FT-IR, UV-Vis, fluorescence and circular-dichroism instruments. A .jws file is an OLE2 compound document; nirs4all-formats reads the reverse-engineered stream pair seen in the committed fixtures and labels channels conservatively from the embedded instrument metadata.

Instruments & software

Produced by JASCO Spectra Manager across the FT/IR, V-series UV-Vis, FP-series fluorescence and CD-1500 / J-1500 circular-dichroism lines. Committed fixtures cover an FT/IR-4100, an FP-8300 and a CD-1500/J-1500 acquisition.

File structure

An OLE2 compound document (magic D0 CF 11 E0 …) with named streams:

• DataInfo — channel count, point count and the spectral axis endpoints;

• Y-Data — float32 ordinate values for all channels;

• BaseInfo — original source path (when present);

• ModuleInfo, SampleInfo, UserInfo, MeasParam — instrument, sample and measurement hint strings used to choose semantic channel labels.

The axis unit is inferred from the endpoint range: nm (wavelength) when the bounds sit within roughly 150-2500, otherwise cm-1 (wavenumber).

What nirs4all-formats extracts

• Signals — one SpectralRecord per file. Single-channel files emit one signal; multi-channel files emit one signal per channel. Channel semantics are inferred from the metadata hints:

  • FT/IR single-channel percent-scale spectra → transmittance (%T);

  • FP-series fluorescence → fluorescence;

  • CD-1500 / J-1500 → cd (mdeg), ht (V), absorbance (dOD);

  • otherwise signal or channel_N.

• Axis — generated from the DataInfo endpoints and point count; kind from the inferred unit.

• Metadata — channel count, channel labels, point count, source path, instrument model and module list, sample label, operator/organization, measurement parameters and the inferred measurement mode.

• Provenance & warnings — jasco_jws_reverse_engineered_data_info, plus jasco_jws_semantic_channels_inferred when a semantic mode was chosen, with source file and SHA-256.

Variants & support status

Variant	Status	Notes
FT/IR transmittance (single channel)	Supported	Percent-scale ordinates typed as transmittance.
Fluorescence (FP-series)	Supported	Single fluorescence channel.
CD / HT / Abs (CD-1500 / J-1500)	Supported	Three labelled channels.
V-series NIR / NRS Raman variants	Planned	Distinct stream layouts; no fixtures yet.
Data / Header / XdataValue stream layouts	Planned	Described by other reverse-engineering projects; pending fixtures.

Limitations & known gaps

• Channel typing is conservative and metadata-driven; layouts whose hints are not specific enough fall back to generic signal / channel_N names.

• V-series NIR, NRS Raman and the alternative Data / Header / XdataValue stream layouts remain pending until fixtures are available.

• JASCO text exports are handled by the row-oriented spectral table reader, not here.

Reference readers

The reverse-engineering follows public JWS projects such as jws2txt and jwsProcessor.

Samples & validation

Fixtures under samples/jasco/ are golden-backed with direct semantic tests: 243.jws (FT/IR-4100, cm-1, 7729 points, transmittance), sample_fluorescence.jws (FP-8300, nm, 301 points, fluorescence) and sample_CD_HT_Abs.jws (CD-1500/J-1500, nm, 1501 points, cd / ht / absorbance). The probe requires both a .jws extension and the OLE2 header, reporting jasco-jws at Confidence::Likely.