|Home Tools Spectral Collections Spectral Collection|
|See also: Dataset Editor, Spectral Collection Data Format, Bookmarks, State Flags in Spectral Collections, Property Editor of Spectral Collections, Logical Combinations in Filter Expressions, Class Names and Unique Class Identifiers
Sometimes it is convenient to store spectra of selected pixels or mean spectra of particular areas for later use. ImageLab supports this by offering spectral collections which are linked to a particular dataset. Each dataset contains exactly one spectral collection. A spectral collection can only contain spectra of the associated dataset.
The spectral collection can store three types of spectra: (1) single pixel spectra, (2) mean spectra obtained from a center pixel and the pixels in a circular area around this pixel, and (3) mean spectra of an arbitrary contiguous region which is defined by a user drawn polygon. Please note that the spectra stored in spectral collections are actually stored in the collection (in contrast to bookmarks which are only pointers to particular pixels). This means that an entry of the spectral collection always reflects the state of the spectrum at the time when it has been added to the collection, later changes are not reflected unless you add the changed spectra as well.
Each spectrum in the spectral collection is augmented by additional information, such as the type of the spectrum, a caption, a class number, user-defined categories and user-defined flags. This additional information can be used to retrieve specific spectra from the collection later-on.
Spectra can be added to the spectral collection in the following ways:
The collected spectra are displayed both in tabular and graphic form. In the collection table you can select any spectrum by clicking the corresponding line. Further you can make a selection permanent by ticking the checkbox in the first column of the table. All selected spectra are displayed in the spectral window below the table, the current selection is always displayed using a thicker line. In order to edit the properties of the selected spectra you have to click the edit button . You can delete the selected spectra by clicking the delete button .
The spectral collection editor provides the following controls: