Avantes AvaSoft

Status: Supported (scoped) · Vendor: Avantes · Extensions: ASCII .ttt, .trt, .tit, .tat, .IRR, .txt; legacy binary .TRM, .ABS, .ROH, .DRK, .REF; AvaSoft 8 binary .Raw8, .IRR8 (and other *8 suffixes)

AvaSoft is the acquisition software for Avantes fibre-optic spectrometers. It writes both ASCII exports (recommended for interchange) and per-acquisition binary files in two generations: the legacy AvaSoft 6/7 single-mode layout and the AvaSoft 8 AVS82/AVS84 container. nirs4all-formats reads the ASCII exports fully and decodes the binary layouts covered by committed fixtures.

Instruments & software

Produced by AvaSoft across the AvaSpec range. ASCII wave tables come from AvaSoft 6/7 (Wave;... columns) and AvaSoft 8 text exports; binary files are the native per-measurement records. Reference behaviour was compared against the documented lightr parser layout and its formulas; lightr is GPL and remains a conformance reference only — no runtime dependency is linked into the MIT core.

File structure

  • ASCII wave tables — a short metadata preamble, then a Wave;... header row, an optional units row, and semicolon-delimited columns (axis first). The delimiter is auto-detected. .IRR two-column whitespace files are parsed as a single irradiance trace.

  • Legacy binary (AvaSoft 6/7) — a 400-byte header stored as little-endian float32 values: version_id (= 70) at byte 0, spectrometer id and user name as float32 ASCII code points, wavelength polynomial coefficients a0..a4 at byte 296, first_pixel/last_pixel at 316/320, measure_mode at 324, then the data at byte 400. The axis is a0 + a1·p + a2·p² + a3·p³ + a4·p⁴ for pixel index p. Processed modes (.TRM, .ABS) interleave scope, white, dark triples; raw modes (.ROH, .DRK, .REF) store one vector plus trailing acquisition values.

  • AvaSoft 8 binary — a 5-byte magic (AVS82 / AVS84), a spectra count, then per-subfile headers carrying subfile length, measurement-mode byte, start/stop pixel, integration time/delay, averages, SPC date, comment, and four float32 payload vectors (xcoord, scope, dark, reference). The reader advances to the next subfile with start + length + 10.

What nirs4all-formats extracts

  • Signals — one SpectralRecord per file or AvaSoft 8 subfile, axis in nm. Processed modes derive the primary signal: transmittance/reflectance (scope − dark)/(white − dark)·100, absorbance −log10((scope − dark)/(white − dark)). Raw and reference channels are exposed alongside (sample, white_reference, dark_reference, scope). ASCII Dark/Ref/Reference/ Sample columns are typed raw_counts; processed columns keep their reflectance/transmittance/irradiance types.

  • Metadata (harmonized top level) — measurement_mode, point_count, first_pixel, last_pixel, integration_time_ms, averages_count, integration_delay; legacy adds detector_temperature_c and version_id; AvaSoft 8 adds magic, acquisition_start_date/acquisition_start_time (decoded from the packed SPC date) and, when populated, instrument_serial, operator, comment. Fixed-length C-string fields are cut at the first NUL.

  • Raw vendor block — metadata.avantes preserves byte-level provenance (spec_id, user_name, wavelength coefficients, raw measure-mode byte, decoded SPC date, smooth/trigger fields).

  • Diagnostics — single-channel legacy raw modes carry avantes_legacy_single_channel:<mode>:companion_files_required (consumers need the companion files to recompute processed signals). When the AvaSoft 8 extension implies a mode that contradicts the observed measure_mode byte, the record carries avantes_avasoft8_extension_mode_mismatch:expected=…:observed=….

Variants & support status

Variant

Status

Notes

AvaSoft 6/7 ASCII wave tables (.ttt/.trt/.tit/.tat)

Supported

Multi-column axis-first tables; per-column signal typing.

Two-column irradiance ASCII (.IRR)

Supported

Single irradiance trace.

AvaSoft 8 text export (.txt)

Supported

Raw dark/reference/sample plus processed signal.

Legacy binary .TRM / .ROH / .DRK / .REF

Supported (scoped)

Processed transmittance + channels, or single raw channel.

Legacy binary .ABS

Supported (scoped)

Same layout/formula path; no committed fixture yet.

AvaSoft 8 binary .Raw8 / .IRR8

Partial

One subfile per fixture; IRR8 calibration not yet applied.

AvaSoft 8 .RWD8/.ABS8/.TRM8/.RFL8/.RIR8/.RMN8/.RMD8, multi-subfile

Planned

Recognised by magic but no committed fixtures yet.

Limitations & known gaps

  • IRR8 irradiance calibration is not applied: the primary signal is exposed as irradiance for discoverability with the avantes_irr8_irradiance_calibration_not_applied warning, and the fourth payload vector is exposed as irradiance_calibration (signal type unknown, values spanning ~1e10 down to ~1e0) rather than a misnamed white_reference.

  • Many active AvaSoft 8 suffixes lack committed fixtures, and multi-subfile AVS8 containers are not yet exercised.

  • The remaining AVS8 acquisition fields are preserved raw but not fully normalized.

Reference readers

lightr (GPL) is the layout/formula reference for the binary paths, used only in the isolated conformance lab. ASCII exports are equally readable with pandas and R read.table; nirs4all-formats adds axis derivation, signal typing and provenance. Subprocess conformance reports against lightr are planned once the local R native chain is available.

Samples & validation

Binary fixtures under samples/avantes/ are golden-backed and probe-locked per suffix: avantes2.TRM (1442 pts, 275.27→1100.13 nm, transmittance 11.840215→−127.179425), avantes_trans.TRM (1623 pts), avantes_reflect.ROH (scope 805.0→774.3), 1305084U1.DRK/.REF, 1904090M1_0003.Raw8 (1019 pts, AVS84, mode 0) and eg.IRR8 (1620 pts, AVS84, mode 4, calibration warning). ASCII fixtures include avantes_export.ttt, avantes_export2.trt, avantes_export_long.ttt, irr_820_1941.IRR and avasoft8.txt. AvaSoft 8 SPC dates are unpacked into top-level acquisition_start_date/time metadata while the raw integer and decoded components remain under metadata.avantes.