Introduction

AVW is a comprehensive set of imaging functions which facilitates full exploration and analysis of multidimensional, multimodality biomedical image data sets. The software also facilitates the development and implementation of advanced imaging algorithms and techniques and easy integration of these into specific applications solutions by imaging software developers. The extensive functionality and interactive speed of this software are unequivocally the key features which distinguish it from other image processing and visualization packages

Organization

The AVW imaging functions are packaged into a library that provides developers with the power of its predecessor, the ANALYZE system, at a callable C language function level. It is extensible, allowing developers to write their own specialized code while still making full use of the imaging capabilities of the package. The functions are completely user-interface independent, allowing for implementation at the applications level in different interface and operating environments. Each library function has a well defined calling sequence utilizing standardized AVW parameters and data structures.

Functions

AVW is a collection of over 600 functions that are accessible to software developers to build advanced image-based application solutions. While only one linkable library is provided, the functionality in AVW can be separated into eight distinct functional groups: Resource, ImageIO, Transform, Process, Segment, Analysis, Visualize and Tiling.

Resource

The Resource functions include the basic routines to create and destroy many of the AVW structures. Also included are list management, verification , and byte swapping routines.

ImageIO

The ImageIO functions provide a user extendable interface which enables the reading and writing of images in many common formats.

Transform

The Transform functions include 2-D & 3-D spatial transformations, densitometric transformations and mathematical transformations. The functions necessary for oblique and curved sectioning, wavelet enhancement and compression transformations, and image registration/fusion are also included in this group.

Process

The Process functions provide a wide variety of histogram operations, spatial/convolution filtering, 3-D FFT's, 3-D Fourier domain filtering and 3-D deconvolution, including fast nonlinear iterative methods.

Segmentation

The Segment functions include thresholding, 2-D & 3-D region growing, automated boundary detection, creation of object maps, multiresolution decomposition, morphological processing and multispectral classification.

Analysis

The Analysis functions include extraction of line profiles, sampling of ROI's which include the computation of size, density, shape and texture parameters (e.g., area, mean, circularity, fractal signature).

Visualization

The Vizualize functions provide all operations necessary to support 3-D display using volume and surface rendering. Supported algorithms for volume rendering include depth-only shading, depth gradient shading, voxel gradient shading, integrated surface projection, maximum intensity projection and summation projection. Multiple object creation and rendering, color transparency (24-bit), image extraction tools, and image measurement tools are supported in conjunction with the volume rendering functions.

Tiling/Modeling

The Tiling/Modeling Functions provides the function to create and extract tiled surfaces from segmented volumes and object maps. The tiled surfaces can be saved in a variety of common CAD formats.