Using the spectra extraction tools

You can extract spectra from image data using multispectral or hyperspectral data. You begin spectra extraction by configuring your data with the Spectra Extraction Configuration window. Focus creates a hyperspectral metalayer to hold the extracted spectra. You must first specify the input file and channels you want to work with. You can select an existing channel or you can create a new one.

The spectra extraction tools let you:

• Collect regions of interest from a hyperspectral image or a scatter plot.
• Review mean and ellipse information in a scatter plot for your spectra.
• Create and review spectra plots from a region of interest.
• Compare spectra signatures of regions with reference spectra from either a spectra library or another image.
• Save spectra to either an XLS or to an SPL library.

When you begin with no open data, the Spectra Extraction Configuration window automatically creates a new map and area for your work. If a map and an area are already open in and the input file has the same georeferencing as the area, a new metalayer is added to the map and area. When georeferencing is incompatible, a new area is added to the existing map.

When you have configured a metalayer, you can access both the Scatter Plot and Spectra Plot windows from a menu in the Spectra Extraction window. Scatter plots and spectra plots are automatically linked to the data you specify in the Spectra Extraction window.