Adding & Managing Signatures

2 min read

There are two ways to add a spectral signature to your library — upload a measurement file, or sample one straight from imagery — and a small set of actions to manage the signatures you own.

Uploading a signature file #

From the Spectral Library, click Upload Spectra, then Choose TXT Files (or drag files onto the dialog — you can add several at once).

File format. Files must be plain-text .txt. Each file has a short header of Key: Value lines followed by the data:

  • Header — metadata as Key: Value lines. Name and Type are required; anything else (Class, Subclass, Origin, Description, units, sample number…) is optional and kept as metadata.
  • Data — two whitespace-separated numeric columns per line: X = wavelength (nm or µm) and Y = reflectance (0–1 or 0–100%).

“` Name: Basanite Type: Rock Class: Igneous X Units: Wavelength (micrometers) Y Units: Reflectance (percent)

14.0510 4.0273 14.0130 3.9140 13.9750 3.7492 … “`

Click Save to add the signature(s) to your library.

📷 Screenshot pending — the Upload Spectra dialog with the file picker and format hint.

Saving a signature from imagery #

You can also capture a signature by sampling a pixel on a rendered scene and saving it — same Name / Type / Class / Origin form, with a Remember last entries option to speed up repeated saves. The full workflow is covered in Plotting Spectra from Imagery.

Managing your signatures #

On any signature you own, the row actions let you:

  • Edit — update the Name, Type, Class and Origin. Note the measured data points can’t be changed after upload; to correct the curve, upload a new file.
  • Share — grant view-only access to teammates. Pick the users and confirm with Share; clearing everyone you’d shared with removes access again. Recipients can see and compare the signature but can’t edit, share or delete it.
  • Delete — remove a signature. Deletion is permanent from your library; deleting several at once requires selecting two or more that you own.

Public and reference signatures, and signatures a teammate shared with you, are read-only — their manage actions are disabled. Unless you share it, a signature you add stays private to you.

Good practice #

  • Validate your spectra before uploading — clean wavelength/reflectance columns and a clear Name.
  • Lean on the public reference library as a benchmark when naming and classifying your own material.
  • Keep your library tidy (consistent Types and Classes) so filtering and comparison stay fast — see The Spectral Library.
Updated on July 28, 2026