GAP LIGHT ANALYZER (GLA), Version
GLA 2.0 is imaging software used to extract forest
canopy structure and gap light transmission indices from true-color hemispherical
- Scientific software (Windows 95/98/NT) to import,
display, and analyze digital hemispherical canopy images.
- Includes "region of interest" image-processing
functions: e.g., image threshold, brightness, contrast, colour fill,
- Designed to process large numbers of photographs
taken from numerous sites - individual configurations can be created
for different camera lenses and orientations, regional climatic patterns
and growing seasons, and topographic settings.
- Extracts canopy structure data (gap fraction, canopy
openness, effective LAI) and gap light transmission indices. Also provides
a number of stand-alone utilities that will compute and display daily
extraterrestrial radiation, sunfleck duration and frequency distribution,
solar positions and intensities, and sky-region brightness.
Modelling and Application Design
Frazer , Simon Fraser University, Burnaby, B.C.
Dr. Charles D. Canham, Institute
of Ecosystem Studies, Millbrook, New York
Dr. Pamela Sallaway,
Spatial Solutions, Inc., Victoria, B.C.
Dimitri Marinakis, University of Victoria, Victoria, B.C.
Forest Renewal BC Research Grant to:
Dr. Kenneth P. Lertzman, Simon Fraser University, Burnaby, B.C.
Copyright (c) 1999: Simon Fraser University, British
Columbia, and the Institute of Ecosystem Studies, New York.