New image-modeling software used for 3-D analysis of biological EM data on silicon graphics computers

Since the early 1980’s, there have been several software packages available for no or low cost that have been developed for image processing of 3-dimensional (3-D) biological images as well as several viewing packages that can be used for viewing 3-D data sets. Work has been done to develop a modeling program that can make interactive 3-D models in stereo, but there is a present a gap between the image processing and model viewing steps for complex 3-D biological data. Although packages available for no or low cost have only rudimentary model building tools the biologist would like to have as accurate a 3-D model as possible. Here we describe a new image modeling software package for the 3-D analyses of biological EM data. We have developed a useful software package (IMOD, Image Modeler) that allows the user to draw two dimensional contours in 3-dimensional image data. The power of IMOD is the ability to see the 3-dimensional image data in several different views at the same time.