A six-pack for the Mac.
(Macintosh-based image processing software)
||ESD: The Electronic System Design Magazine
Institute of Health / NIH Image
||Hollinger, Steven J.
|© Sentry Technology Group, Inc.
Image processing on the microcomputer was revitalized
with the introduction of the Macintosh II. The Mac II, IIx, and IIcx excel
in their abilities to acquire, manipulate, communicate, and output data.
Built on a solid graphical foundation, the Mac II is ideal for scientific
image processing applications. It offers an environment that boasts power
and flexibility, yet is intuitive enough for researchers unfamiliar with
It is no coincidence then, that six image processing software packages
have been released for the Mac: Graftek's Ultimage, 2Ai's Bigmage, MacRAIL
and Image Analyst from Automatix, Perceptic's TCL-Image, and Image 1.06,
a shareware program developed at the National Institutes of Health (Table
1). All claim to address applications ranging from medical to astronomy.
They supply the fundamental features that should be at any image scientist's
fingertips. In addition, each package has strengths and weaknesses that
suit it to specific applications. MacRAIL and TCL are image processing
environments for custom application development. The remaining four products - Ultimage,
Bigmage, Image Analyst, and Image 1.06 - are complete applications with
a standard Macintosh look and feel. Because these four programs use the
Mac interface, a series of processing or analysis functions can be accomplished
without learning special command languages or even consulting the manual.
User-Friendly Image Processing
The imaging platform of choice used to be a DOS-based workstation, such
as a rugged IBM AT. With the Mac family, innovations in application design
have left DOS and OS/2 (and, to some extent, UNIX) systems playing catch-up.
These innovations include a standardized user interface, extensive support
of ROM-based libraries, and a commitment to object-oriented programming
languages. Apple's position in the image processing arena will be further
strengthened by the maturation of true multitasking operating systems
(such as A/UX).
With its ROM-based Toolbox, Mac offers developers a set of libraries for
interfacing with lab equipment using the standard Mac interface of pull-down
menus and dialogue boxes. Below the level of the Toolbox, image applications
can take advantage of the hardware horsepower driving the Mac II line.
Sending a positive signal to the image processing market is Apple's commitment
to the Motorola 680X0 family. The Mac II boasts a 16-MHz 68020 CPU and
a 68881 floating-point coprocessor. Both the Mac IIx and IIcx have a 68030-based
motherboard featuring the 68882 math chip.
The Mac's excellence as a true imaging platform hinges on the simplicity
with which data can be moved from source to destination. Of course, the
user interface facilitates this, but other aspects of the Macintosh environment
are equally important. For instance, Apple's PICT file format has proven
successful for moving images, text, and graphic primitives between applications
and to/from input and output devices. Under the Mac's Multifinder, multiple
application windows are managed. Also, information can be passed back
and forth between each application through the Mac's Clipboard. Simply
put, Macintosh applications and devices talk to each other in a universal
Use of color has also been standardized. To run a color image processing
application on the Mac, only the Apple color monitor and an 8-bit color
video display card are required. With the release of Apple's 32-bit QuickDraw,
display cards supporting 32-bit color will also run software based on
the 8-bit standard. No longer will the lab scientist have to fumble for
a manual to figure out if a DOS image package supports the IBM 8514 standard,
EGA, CGA, MDA, VGA, or super VGA.
Typically, imaging operations fall into one of two categories: processing
or analysis. Image processing refers to the manipulation of image data;
image analysis refers to the extraction of statistics. A crime lab intent
on recovering fingerprints from a dusted glass will likely perform a series
of processing functions to enhance a scan of the print. On the other hand,
a robot hand guided by a machine-vision system will move to specific coordinates
derived through image analysis. To meet the needs of these two different
markets (scientific versus industrial), image processing packages generally
perform both processing and analysis.
Common to all of the packages reviewed is a set of fundamental techniques
for image restoration and manipulation. These include filters (e.g., smoothing,
gradient, sharpening, edge detection, and median), histogram equalization,
geometric transformations (e.g., rotation and flipping), color palette
manipulation, and logic/arithmetic operations (e.g., add, multiply, and
XOR). Aside from subtle differences in how these features are accessed,
performance does not vary significantly from application to application
during the actual processing phases. More significant differences exist
in other areas, however,
In the realm of image analysis, the only features common to all six packages
are histogram display and pixel intensity display. Beyond these two basic
image descriptors, the packages differ. For instance, Image Analyst easily
recognizes and describes relationships between image objects over time
(e.g., the bolt is now 2 mm from the nut). On the other hand, TCL can
facilitate the restoration of image features (e.g., a fetus description
mottled by noise in an ultrasound).
Ultimage from France's Graftek targets industrial, scientific, and research
applications. U.S. distributor GTFS, Inc. (Santa Rosa, CA) describes Ultimage
as a modular toolbox with primary and advanced features for image enhancement,
interpretation, and analysis.
Ported from the VAX to the Mac, the package debuted at the Macworld Expo
in Aug. 1988 (under the name Optimage). Ultimage developers claimed that
it would run at least 20% faster than its MicroVAX twin, and would use
Levco's (San Diego, CA) Transputer board to up performance. At the time
of writing, Ultimage (vl.2.1) does not support the Levco board.
Of the packages reviewed, only Ultimage ships without full functionality.
Several advanced image processing options appear in the menus, but are
disabled. Also, scripting and zooming are unavailable. By including menu
items that will appear in future versions, Ultimage does show where Graftek
plans to take the product.
Even though Ultimage's functional items are difficult to sieve from the
dream list of menu choices, the ones that work are well developed and,
in some instances, provide exceptional user interfaces (Figure 1). Most
Ultimage options are selected from pull-down menus. From the File menu,
PICT (with full-color palette import) and gray-scale TIFF image files
can be opened. The Acquire command can be used to open images from Data
Translation's (Marlboro, MA) QuickCapture board. In addition to the menu
items, a small settings window allows selection of preferences for palette,
cursor style, and threshold.
Ultimage provides support for all fundamental processing operators. For
most operations, the user can act on the source image or produce a new
output image. a rectangular selection (region of interest) can be made
of part of the image, but it is only active for some processing options.
For example, convolutions and filters do not use the region of interest
(ROI), but lookup table (LUT) operations do. Undo is not supported for
all operation classes, either. According to GTFS, these inconsistencies
are being addressed.
Ultimage's morphological processing operators, logic/arithmetic operations,
and reporting features are the program's real strengths, especially for
disciplines involving binary images. The package offers a spectrum of
primary and advanced morphological filters. One option provides a checkbox
for displaying iterations. In this way, morphological filters can be viewed
as they operate on images. Support of these operations makes Ultimage
attractive for use in biomedical research, where objects must be manually
identified, enhanced, and characterized.
Once an image is converted to binary form, a Particle option can be selected
to perform an analysis on individual features. Data can be extracted and
displayed as scatter plots, distributions, or statistics. By placing the
cursor close to a particular object's centroid, characteristics such as
the axis of least inertia for that blob are presented. Because Ultimage's
macro option is disabled, automation for gathering statistics is not possible.
Ultimage demonstrates a unique approach to processing arithmetic and logic
operations. To carry out these functions, a dialogue box is used that
acts as an engine for applying complex functions to images. The Arithmetic/Logic
Operators dialogue box lists the open images and the available operators.
First, an image is selected from the list. Next, an operator such as Multiplication
can be chosen from a comprehensive list of logic and arithmetic operations.
At this point, either another image of identical resolution or a constant
is selected. The values in the second image or the constant are multiplied
by the corresponding pixel intensities in the source image. Output values
of this sequence can be used as new inputs, and a new operator can be
chosen from the list. Finally, the resulting values can be output to a
displayed image. In this way, multiple operations can be applied to various
images without leaving the dialogue box.
Another strength of Ultimage is its provision of some basic Fourier domain
processing operations. These features are often used to eliminate noise,
identify periodic artifacts, or even compress image data. Ultimage carries
out high- and low-pass filtering on images in the frequency domain, and
performs inverse Fast Fourier Transforms (FFTs) to reproduce the enhanced
image in the spatial domain. Neither Ultimage nor any other package reviewed
can mask discrete points in the frequency domain - a desirable option for
eliminating image noise.
Ultimage's use of color is limited. If the document's own palette is undesirable,
five standard palettes can be selected - black and white, rainbow, temperature,
gradient, and binary. However, it is not possible to create a custom palette
for pseudocoloring images.
In sum, Ultimage is fine for performing a rapid series of image processing
operations in lab settings. Though it does not include important items
like zooming and pseudocolor. Ultimage is useful as an engine for prototyping
image restoration experiments.
Another package reviewed, Bigmage from 2Ai (Advanced Analysis and Image,
Pasadena, CA) is a lower-cost version of a medical imaging package called
Multimage. Developed for the Dupuytren Hospital in Limoges, France, Multimage
ran on a Bull mainframe, and was later ported to Sun. Bigmage was introduced
for the Mac II platform in Jan. 1988.
Image processing using Bigmage is intuitive and straightforward for the
Mac-initiated. Bigmage adheres to the standard Mac user interface, with
pull-down menus and dialogue boxes. It uses the Mac File menu, and supports
the Clipboard commands in the Edit menu for cutting and pasting.
The Big Picture
Providing a solid foundation of image processing functions, the package
includes advanced features for biomedical and scientific imaging. Bigmage
and Ultimage have many features in common. Like Ultimage, Bigmage is very
strong in binary and primary morphological operations (Figure 2). Basic
operations include thinning and thickening, typically used to identify
objects of interest. For instance, an erosion might be used to eliminate
bumps in an image, or a dilation might be used to fill in valleys.
More sophisticated morphological functions, such as rolling ball and top-hat
operators, are also supported. Bigmage distinguishes itself from Ultimage
with its Define menu. It allows unique convolution kernels, a connectivity
matrix (used for describing the relationship between a particle and its
neighbors), and other custom settings. At the time of this writing, 2Ai
has also released a version of Bigmage that fully supports integration
with MPW C objects externally compiled, and invoked under a user menu.
The package offers rudimentary options for image analysis. A status window
can be opened that displays morphological characteristics of an image
(i.e., centroids, areas). Bigmage, as in Ultimage, displays pixel intensities
along a user-defined line in the image. Similarly, the line disappears
once the intensity histogram is displayed. For histogramming, a normalized
or cumulative histogram can be chosen. An excellent feature for maintaining
statistical data is the program's ability to open text files to type in
notes, while keeping image windows open for viewing.
Although Bigmage supports basic geometric transformations for rotation
and symmetry (flipping), it lacks translations for scaling and stretching.
While Bigmage can perform an FFT on an image, and then apply a low-or
high-pass filter to the resulting frequency plane, the program does not
include the inverse FFT function.
Bigmage opens images of the SATIE format, as well as two proprietary format
types: one for gray-scale and a second for color palette storage. During
testing, Bigmage would not import the color palette of a PICT file, but
did import the image itself. TIFF files were also supported. Bigmage offers
pseudocolor support that is simple and well adapted to allowing the Mac's
8-bit color palette to be adjusted.
2Ai claims that Bigmage is compatible with its parent program, Multimage.
If so, this package provides advanced medical imaging scientists an upgrade
path for faster processing on Sun workstations. Bigmage ships with a manual
and program disk. The documentation goes beyond the standard "How
to use" demonstrations and offers approaches for solving processing
problems. Most functions are described under the headings, "What
does it do?" and "How does it work?" However, these helpful
explanations are not meant for the novice. Bigmage falls into the category
of advanced processing. The program disk also includes a number of demonstration
files that step through various image processing functions.
A rich, intuitively built image processing program, Bigmage is a particularly
useful tool for recovering information from binary and gray-scale images.
Bigmage's compact, intelligently organized menus are designed to carry
out a rapid succession of operations. They also make Bigmage a good choice
for specialists who are not entirely familiar with image processing jargon.
Railing on Images
Ultimage and Bigmage are typical of applications software that requires
little or no programming talent. MacRAIL from Automatix (Billerica, MA)
is not a typical Mac application. As one of the industry leaders in robot
and machine-vision products, Automatix has delivered a package that combines
a solid infrastructure of imaging tools in the form of an extensible programming
Originally developed from machine-vision and robot programming, the Automatix
RAIL ran on a proprietary 68000-based system. Along with the rest of the
Automatix machine-vision and control products, RAIL has been ported onto
the Mac platform as MacRAIL. Because MacRAIL is an environment, not a
canned application, its power lies in its flexibility. With MacRAIL, runtime
image processing programs or interactive scripts can be created. MacRAIL
moves ahead of its predecessors by including a menu package that helps
the programmer access the Mac user-interface libraries. With this added
functionality, applications created in MacRAIL have the look and feel
of the true Mac interface.
MacRAIL is a Pascal-like interpretive programming language that is block
structured and not strongly typed. (All variable types do not need to
be specified in advance because MacRAIL recognizes them automatically.)
It has all the control constructs of Pascal (if, then, else, and so on),
but MacRail also has built-in variables and functions for image acquisition,
processing, and analysis. Using the Automatix developer's package, optimized
extensions to MacRAIL can be built in MPW C and linked with the MacRAIL
MacRAIL performs simplified image processing, analysis, and control functions
by recognizing specific commands (Figure 3). These commands can be saved
as a named script that will run when invoked under MacRAIL. With scripting,
the scientist can actually prototype a unique image processing application
or environment. The MacRail scripting worksheet works much like the commonly
used MPW development worksheet and supports the Edit, Find, Mark, and
Another strength lies in the provision of access software to the Mac user-interface
library. The MacRAIL Menu Package creates a link between lower-level processing
software and the standard Mac dialogue boxes, alert boxes, pull-down menus,
and so on.
Both image analysis and processing capabilities are robust, and the software
includes extensive manipulation capabilities for image processing. The
dept of MacRAIL's analysis features, especially for machine-vision applications,
is significant. MacRAIL has built-in functions for full 3D camera calibration.
Three-dimensional calibration makes it possible to compute a mathematical
model for transformations between real-world objects and image coordinates.
Most packages only allow a magnification factor to be specified, which
is best suited for measuring 2D coordinates. To identify any image point
as an (x, y, z) coordinate, MacRAIL performs a perspective transformation
that finds its location in 3D space.
MacRAIL also has built-in functions for stereo sensor pair calibration
and structured lighting sensor calibration, the two most common techniques
for recovering depth from 2D images. For many machine-vision applications,
these types of calibrations are not extras; they are necessities. MacRAIL
has built-in functions for image enhancement with mean and median filters
as well as an edge-detection package. Moreover, MacRAIL can perform basic
morphological operations like erosion and dilation. Because it was not
originally designed for use in purely scientific environments, the package
relies on third-party support for more obscure functions, such as the
morphological sets found in Bigmage and Ultimage. In fact, Image 1.06
from the National Institutes of Health is also available through Automatix.
Processing can be initiated by an external event, such as cell motion
under an electron microscope or by a machine part passing a photoelectric
sensor. Without human intervention MacRAIL can trigger a strobe that will
light an event and capture an image in sync with the pulse to perform
a measurement on the image, setting up multiple regions of interest; and
output computations. Hardware support is of primary importance in the
lab as well as on the manufacturing floor. MacRAIL provides extensive
real-world input and output tools. Specifically, it has software support
for third-party digital I/O, analog I/O, and parallel and serial communications.
National Instrument's (Austin, TX) GPIB boards are fully supported in
both C and MacRAIL.
MacRAIL comes with two disks, a user manual, and a debugger. Also included
is a MacRAIL-based application program called ASAP, which is nearly identical
to Image Analyst, except that ASAP can trigger a sequence on an input
strobe, or can signal an output port on a pass/fail condition. MacRAIL
requires the Data Translation QuickCapture board in its minimum configuration.
Automatix offers a selection of MacRAIL-level application packages tailored
for image geometry, statistical analysis, camera calibration, and optic
configuration. Written in MacRAIL or C, the packages are either linked
under MPW or run as scripts in the MacRAIL worksheet. The Profiler is
a performance analysis package that discovers where time is being spent
in MacRAIL applications, so that intensive sections of code can be optimized.
A statistical performance analysis package aids in the identification
of trends found during the analysis of a series of images. Automatix also
offers training and technical support programs for MacRAIL.
See the Image Analyst
Image Analyst represent Automatix's foray into the image processing marketplace
(apart from dedicated machine-vision systems). With Image Analyst, standard
image processing functions such as filtering or convolving an area of
interest can be performed. Image Analyst's strength, however, lies in
the integration achieved between the developed and the powerful MacRAIL-based
analysis library. With true expertise in machine vision rather than scientific
processing, Automatix has created a package that seems to complement rather
than compete with the others reviewed for this article.
Image Analyst is written in MacRAIL and provides access to most of MacRAIL's
image processing and analysis functions. In fact, when Image Analyst is
invoked, it takes about two minutes for the entire MacRAIL library to
be loaded (though MacRAIL is not directly accessible to Image Analyst).
With Image Analyst, macro-like sequences of operations on an image can
be generated, then saved, run, or edited via a Mac interface.
When setting up processing sequences, Image Analyst can maintain multiple
ROIs in the image field (Figure 4). For each ROI, one or more types of
analyses can be performed (e.g., connectivity, edge detection, image enhancement,
image correlation, or gray-scale analysis). Image Analyst automatically
computes features in an ROI according to the selected processing category
assigned to that area. For example, when connectivity has been selected,
access to information such as minimum identifiable blob size in the ROI
is provided. For each identified object in the image, the centroid, orientation
of major and minor axis, area, roundness, and moments of inertia are also
computed. Based on these statistics, measurements can be taken as an additional
step in the sequence of operation. Complementing the standard measurement
tools (point-to-point, point-to-line), Image Analyst has routines to detect
lines or object boundaries within an ROI. For example, the Hough Transform,
used for identifying robust lines within an image, can be applied before
performing a line-to-point measurement.
Generated sequences can be edited and run either automatically or by command.
The results of performing a sequence can be saved to file, printed, or
displayed on a monitor. The specifics of processing for each ROI are saved
as properties of the ROI. When the ROI is moved around the image, the
processing and analysis operations that were performed on the ROI before
it was moved are repeated on the new ROI. This process of automating ROI
operations is useful in scenarios where the ROI must be found using a
vision system, rather than a human operator.
Image Analyst does not include support for I/O with triggers on external
devices. Triggers are essential in industrial environments where vision
is used for automating the manufacturing or inspection process, and in
fact both MacRAIL and the companion application ASAP support them. Image
Analyst is extremely useful in setting up, prototyping, or generating
statistics from a typical automation scenario. However, for ultimate device
control, MacRAIL is required. Image Analyst supports but does not require
the Data Translation Quick Capture board.
In conclusion, Image Analyst is a high-powered vision/analysis program.
The ability to automate sequences in the Image Analyst package would lend
its power to any image processing discipline which has a projected outcome
and which would require automatic gathering of statistical data. Especially
considering the lack of device control capability. Image Analyst is best
suited for prototyping inspection systems that will later be installed
with custom vision systems like MacRAIL.
Power and Strength
TCL-Image, an image processing environment distributed by Perceptics (Knoxville,
TN), has the strongest image processing base of all the reviewed packages.
TCL was developed in the Netherlands by Multihouse TSI. TCL is not based
on Perceptics' own NuVision hardware accelerator, but rather has been
introduced on other platforms, most recently the Mac II.
TCL is well adapted to generating automated sequences for image acquisition,
image restoration, and feature extraction. Like MacRAIL, TCL is a programming
environment. Unlike MacRAIL, TCL is driven by an interpretive command
language, similar to a system language like Digital's DCL, rather than
a programming language like Pascal. One advantage of TCL's command language
interface is the portability of TCL scripts between platforms, including
Apollo, HP, and 386 machines. Some of the more powerful commands available
on these systems have not yet been brought over to the Mac version of
TCL, including use of a text editing worksheet.
Apart from a File menu for capturing images or quitting, and an Edit menu
for specifying a pathname or using the Clipboard, TCL does not have any
Mac-like tools or options. To perform an image processing function, a
command is invoked through the TCL worksheet. The worksheet is not designed
to use the mouse; only a command at the current prompt can be executed
The processing library is expensive in breadth and depth. For each category
of operations (e.g., convolutions, edge detections, and morphology), TCL
supports a multitude of options. TCL's processing library is relatively
difficult to access, since the cryptic TCL command language must first
be mastered. For example, to perform a Laplacian convolution to detect
the edges in an image, the following must be entered:
[is greater than] LAPL imagein imageout
TCL's standard edge-detection operators like the Sobel, Roberts, and Laplacian
filters are complemented by more unusual ones, like the Kirsch, Robinson,
and Lee-Haralick-Verbick. These and many more are not found in other packages.
TCL's connectivity library is equally dense. The TCL manual supplies helpful
references to technical literature where the origins and use of the more
obscure functions can be found. Also, a large demonstration script library
is provided as an introduction.
Elementary programming constructs, useful in an interpretive environment,
are offered, as opposed to more complex expressions associated with compiled
languages. FOR...NEXT loops and WHILE...DO instructions are all part of
the TCL language. Calls to subroutines are supported, but these must be
script-based since TCL does not yet support externally compiled modules.
TCL has an online Help command for quick reference and a Journal command
that records an interactive session with TCL into a script file.
TCL maintains two internal image file types, one of integer type (as in
the other products reviewed and one containing floating-point representations
of the image. Using floating-point pixel intensities, many complex operations
can be carried out with highly accurate results. For example, rotations
typically degrade image quality as fractional pixel intensities are truncated.
By maintaining a floating-point representation, TCL rotations preserve
significant information, protecting the integrity of the original pixel
information. For some operations, it may be necessary to convert from
the integer format to the complex format. One drawback to TCL's file format
support is the absence of import and export functionality. An image must
enter the TCL environment through the frame capture board, or a test pattern
In contrast to MacRAIL, with its strong analysis orientation, TCL's strength
is its ability to customize advanced image processing sequences. The intuitive
Mac interface has been sacrificed in order to maintain portability across
various TCL platforms. With the addition of a Mac interface and a line
option for compiled modules, Perceptic's TCL-Image would be an even more
powerful package for custom processing.
Simple and Intuitive
Image 1.06 is a public domain program from the National Institutes of
Health (Bethesda, MD). The program can be used to acquire, enhance, measure,
and edit images. This is the first program any developer interested in
image analysis should become familiar with because it is both simple and
Image 1.06 includes Pascal source code and example images. Because the
source code is included, the package provides a strong base on which a
researcher can build. Image 1.06 offers most of the elementary image processing
operations. It has menu options for edge detection, inversion, contrast
enhancement, smoothing, sharpening, dithering, noise reduction, and histogram
Unique to the six packages reviewed, Image 1.06's tool palette holds a
variety of MacPaint-like image retouching tools, as well as several image
processing tools. For retouching, tools include a paintbrush, airbrush,
eraser, eyedropper, and smudging finger. Several outlining tools allow
the selection and manipulation of nonrectangular regions. A ruler tool
makes simplified measurements in pixels, metric, or U.S. standard units.
For image analysis, a counting tool counts objects in an image, marks
them, and records their X-Y coordinates. Results can then be displayed
as a simple table.
The density profile tool plots the gray levels in an image, using either
a fixed scale or selectable maximum and minimum values. Resulting plots
can then be cut and pasted into other applications, either as a graph
or as a column of numbers for transfer to analysis and plotting programs.
The CLUT tool lets color LUTs be modified by clocking and dragging in
the CLUT window. Image 1.06 supports four types of LUTs: gray-scale, pseudocolor,
Mac II system palette, and 256-continuous-color spectrum. The CLUT tool
can also highlight and then measure ROIs based on their density.
Two kinds of palettes can be created and saved. Pseudocolor palettes are
limited to 32 colors. Colors can be edited using the eyedropper tool,
and the number of colors can be reset. For more complex palettes with
up to 256 colors or gray levels, image 1.06 recognizes Mac CLUT resource
Images can be captured from Data Translation's QuickCapture board. As
with the other packages, the files can be imported or exported in TIFF
and PICT formats. Image 1.06 also does dithering for printing on a black-and-white
printer, and halftoning for printing on a gray-scale printer. Print commands
can be used to print the image, a density or calibration plot, the contents
of the histogram window, measurements made with the Measure command or
the ruler, or the X-Y coordinates found with the point measurement tool.
Good Starting Point
Image 1.06 is a good starting point for scientific image processing, and
obviously the best value. All of the basic processing functionality is
provided - even in source listings. Image 1.06, the first image processing
software for the Mac, is still undergoing significant revisions, with
future features promised to include more than the 32 pseudocolors, as
well as extensive support for image arithmetic. Image 1.06 can be downloaded
from many Mac bulletin boards and group libraries.
With the six packages, the Mac II becomes a true workstation for an array
of image processing markets. Ultimage from Graftek and Bigmage from 2Ai
Inc. are useful in environments where images are manipulated to detect
features, typical in biomedical research settings. MacRAIL from Automatix
is tailored for automated machine-vision environments requiring customization.
Also from Automatix, Image Analyst is geared toward more intensive analytical
scenarios - for inspection, statistics gathering, or pattern recognition.
With its command language interface and impressive processing library,
TCL-Image from Perceptics is well suited to the automated feature extraction
or image restoration markets. Finally, NIH's Image 1.06 is written by
and for the medical community, but its shareware status and source code
listings make it especially attractive as a stepping-stone to advanced
processing or analysis.
S. H. Pierce & Co.
The author would like to thank Carol McGarry for assistance with editing
and Dr. John Agapakis for contributions in image analysis evaluation.