FT4FTIRS

FT4FTIRS (Fourier Tranform for Fourier Transform Infrared Spectroscopy) is a Python package for processing interferograms from FTIR (Fourier Transform Infrared Spectroscopy) data. It supports reading Bruker OPUS files, processing interferograms (apodization, zero-filling, Fourier transform), and extracting spectra for further analysis.

Installation

You can install the package using pip:

pip install ft4ftirs

Quick start

from ft4ftirs.io.bruker_opus import BrukerOpusReader
from ft4ftirs.processing.pipeline import SpectralPipeline
from ft4ftirs.processing.scan_averaging import average_spectra

# Load the interferogram(s) plus the instrument-recommended apodizer, phase
# corrector and zero-filling factor from a Bruker OPUS file.
reader = BrukerOpusReader()
data = reader.load("sample.0")

# Run the interferogram -> single-beam spectrum pipeline (apodization,
# zero-filling, FFT and phase correction).  Passing the file's zero-filling
# factor reproduces the spectral point spacing OPUS produced.
pipeline = SpectralPipeline(
    data["apodizer"], data["phase_corrector"], data["zero_filling_factor"]
)

# A bidirectional file holds a forward and a backward scan.  They carry
# different phase errors, so transform each one separately and average the
# resulting *spectra* -- never the interferograms.
spectrum = average_spectra([pipeline(ig) for ig in data["interferograms"]])

print(spectrum.wavenumbers, spectrum.intensities)

See examples/example_opus.py for a complete, runnable script.

Package layout

• ft4ftirs.data — Interferogram and Spectrum containers.
• ft4ftirs.io — instrument file readers (currently Bruker OPUS).
• ft4ftirs.processing — apodization, ZPD finding, phase correction, and the SpectralPipeline.
• ft4ftirs.analysis — transmittance/absorbance/reflectance conversion and spectral quality metrics.