Foss / WinISI

Status: Supported (scoped) · Vendor: Foss (NIRSystems) · Extensions: native .cal, .nir; .txt, .csv (exports); native .DA, .eqa (not yet sampled)

Foss NIRSystems / WinISI / ISIscan is a long-standing industrial NIR platform. nirs4all-formats now decodes the native .cal / .nir binaries directly through a reverse-engineered reader, and still reads the exported text or CSV spectral matrix where only an export is available: Wavelengths: text blocks through the spectral-matrix reader and wide CSV exports through the delimited-text reader. The remaining native project formats (.DA, .eqa) are not yet sampled.

Native .cal / .nir reader

The native reader decodes the WinISI / ISIscan binary container directly. It is routed by header signature, never by extension: a file is claimed only when its binary header carries the version word followed by an ASCII ISIscan / NIRSystems marker. This is what resolves the .nir extension collision with BUCHI NIRCal — WinISI never fires on a BUCHI file and BUCHI never fires on a WinISI file, so each keeps its own .nir payloads.

Three probes are exposed, all at Definite confidence:

  • foss-winisi-cal — calibration .cal files (file-type word 2) carrying per-sample spectra and constituent reference values.

  • foss-winisi-nir — spectra-only .nir files (file-type word 1), no constituents.

  • foss-ds-nir — the same container emitted by the newer FOSS DS-series benches (DS2500, DS3 F). These carry no ISIscan/NIRSystems string; they are pinned instead by a NIRS DS... instrument model at offset 0x82. Spectra-only (file-type word 1), decoded identically to foss-winisi-nir.

Each sample becomes one SpectralRecord:

  • Signal — an absorbance spectrum (f32), axis Wavelength in nm built from the file’s segment table of f32 start/step/end values.

  • Targets — the constituent reference values (e.g. CDpcMS, NDpcMS, K, P), with constituent names normalised to lower-case target keys.

  • Metadata — sample_number, product_code, acquired_unix_time, acquired_utc, instrument_model, master_number, constituent_count, file_kind, version_word, record_index.

  • Provenance — source file + SHA-256, reader name and version, plus the foss_winisi_reverse_engineered_blocks warning.

Instruments & software

Produced by WinISI / ISIscan for Foss NIRSystems instruments (e.g. XDS, NIRSystems 5000) when exporting calibration or sample data. Committed fixtures include a synthetic WinISI-style matrix export and two real Foss XDS CSV exports from a University of Cordoba (sensAIfood) dataset.

File structure

  • Wavelengths: text export — a labelled wavelength block followed by one-spectrum-per-row data; read as a spectral matrix.

  • Wide CSV export — leading metadata / target columns (ID, properties) followed by numeric wavelength headers, one sample per row; read as delimited text. The delimiter is auto-detected.

What nirs4all-formats extracts

  • Signal — one spectral signal per sample row, axis in nm.

  • Metadata — ID is promoted to metadata.sample_id.

  • Targets — numeric property columns (e.g. Moisture, Protein, Year) become per-record targets.

  • Provenance — source file + SHA-256, reader name and version.

Variants & support status

Variant

Status

Notes

Native .cal (calibration)

Supported (native)

foss-winisi-cal probe; spectra + constituent targets. Sniffed by header signature.

Native .nir (spectra-only)

Supported (native)

foss-winisi-nir probe; spectra, no constituents. Sniffed by header signature.

Native DS-series .nir (DS2500, DS3 F)

Supported (native)

foss-ds-nir probe; same container, pinned by the NIRS DS model at 0x82, no ISIscan/NIRSystems string. Spectra-only.

Wavelengths: text matrix export

Supported

Read via the spectral-matrix reader.

Wide CSV export (metadata/targets + numeric headers)

Supported

Read via the delimited-text reader.

Native .DA / .eqa

Not yet sampled

No binary fixture found yet; not reverse-engineered.

DS3 / Inframatic property-only reports

Detected / refused

No numeric spectral headers, so explicitly refused.

Limitations & known gaps

  • The native .cal / .nir reader is reverse-engineered (hence the foss_winisi_reverse_engineered_blocks warning); the wavelength axis is reconstructed from the file’s segment table of f32 start/step/end values.

  • Native sample-block strides are detected from record headers. Most 1050-point files use the compact 24-byte post-spectrum gap, while DS3 F 700-point files use the 128-byte-aligned variant.

  • The real native vendor binaries are local-only under samples_local/foss_winisi/ (private, licence TBD); only the synthetic synthetic.cal fixture is redistributable.

  • The remaining native .DA / .eqa formats are not yet sampled or reverse-engineered, so calibration-equation payloads are not extracted.

  • The export path does not replace the native reader; it only covers the text / CSV interchange where no native binary is available.

Reference readers

The text and CSV exports are equally readable with pandas or R read.table; nirs4all-formats adds axis detection, target promotion and provenance. No open native reader is available for the binary project formats, so the native .cal / .nir reader is validated against the ISIscan .txt exports of the same files rather than against a third-party binary loader.

Samples & validation

Fixtures under samples/foss_winisi/ are golden-backed / read-tested: synthetic.cal (native reader; 2 samples, 6-point nm axis 1000–1014 nm, moisture / protein constituent targets), synthetic_winisi_export.txt (50 records, 200-point nm axis, protein target), foss_xds_barleyground_sensAIfood.csv (7 records, 1050 points, 400–2498 nm) and foss_xds_wheat2_sensAIfood.csv (2 records, same wide layout). DS3 / Inframatic-style property-only reports are kept as expected refusals.

The DS-series native path has its own golden-backed fixtures under samples/foss_winisi/: synthetic_ds2500.nir (foss-ds-nir; 4 samples, two-segment 100-point nm axis, NIRS DS2500 model) and synthetic_ds3f.nir (3 samples, single-segment 50-point nm axis, NIRS DS3 F model).

The real native corpus is local-only under samples_local/foss_winisi/ (private, licence TBD). The ISIscan/NIRSystems files are validated against their .txt exports: yamtot_2026.cal (18 records, axis 400–2498 nm / 1050 pts, spectra matching to float32 precision ~5e-8, constituents exact), ando4_2026.cal (20 records / 9 constituents), D2026_20240328.cal (18 / 5) and yamtot_2026.nir (16 / 0 constituents). The DS-series files have no vendor text export, so fileDS2500CRAW.nir (10 records, 400–2498 nm / 1050 pts) and fileDS3FCRAW.nir (20 records, 1100–2498 nm / 700 pts) are checked structurally (record count, axis endpoints, instrument model, finite plausible absorbance).