Complex multidimensional datasets generated by digital imaging
spectroscopy can be organized and analyzed by applying software and
computer-based methods comprising sorting algorithms. Combinations of
these algorithms to images and graphical data, allow pixels or features
to be rapidly and efficiently classified into meaningful groups according
to defined criteria. Multiple rounds of pixel or feature selection may be
performed based on independent sorting criteria. In one embodiment
sorting by spectral criteria (e.g., intensity at a given wavelength) is
combined with sorting by temporal criteria (e.g., absorbance at a given
time) to identify microcolonies of recombinant organisms harboring
mutated genes encoding enzymes having desirable kinetic attributes and
substrate specificity. Restriction of the set of pixels analyzed in a
subsequent sort based on criteria applied in an earlier sort ("sort and
lock" analyses) minimize computational and storage resources.
User-defined criteria can also be incorporated into the sorting process
by means of a graphical user interface that comprises a visualization
tools including a contour plot, a sorting bar and a grouping bar, an
image window, and a plot window that allow run-time interactive
identification of pixels or features meeting one or more criteria, and
display of their associated spectral or kinetic data. These methods are
useful for extracting information from imaging data in applications
ranging from biology and medicine to remote sensing.