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Vol.32 No.3 August 1998
ACM SIGGRAPH



Beyond Paint



Rosalee Wolfe
DePaul University


August 98 Columns
Professional Chapters Student Art Gallery


Rosalee Wolfe
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Figure 1: This demonstrates GIMP’s variety of textures.
Figure 1: This demonstrates GIMP’s variety of textures.

This is another installment in the continuing “scrounge series” that addresses the problem of locating and acquiring graphics software and hardware for classroom use given the realities of tight resources. The last issue discussed free and low-cost 3D graphics modeling and rendering packages. This article covers several freeware and shareware options for digital painting and image processing. Although free paint programs come bundled with several popular operating systems, they are relatively limited in what they offer to students. This article compares features and costs of several packages that provide more than just the basic pen and fill commands.

At a Glance

Table 1 is a quick comparison of five paint and image processing packages and includes GIMP, Graphics Workshop for Windows, NIH Image/Scion Image, Paint Shop Pro and Webfx. The software spans all of the commonly available operating systems and offers a wide range of features.

GIMP

GIMP (GNU Image Manipulation Program) is a flexible program capable of many options usually found only on high-end software. As a paint program it offers brush, pencil, airbrush and clone tools. The clone feature allows a user to make new brushes. Users can choose from a large number of stock textures or create their own for use with the fill or brush tools. It supports alpha channels and full layers functionality, allowing users to dynamically set opacity, stacking order and visibility. Filters include the standard ones such as sharpen, blur and emboss as well as the more exotic types of mosaic, Van Gogh (LIC), oilify and sparkle. Capable of importing and exporting dozens of file types, GIMP also has a batch processing system that frees a user from the chore of converting large numbers of files by hand.

GIMP comes with documentation in HTML format that is compatible with any browser, but there is no help feature in the software itself. A large range of tutorials and examples are available on the GIMP Web site. GIMP runs on any Unix platform with X Window System, but you will have to compile it for your own system. Installed, with documentation, GIMP requires about 50 MB of disk.

GIMP is available for download at the GIMP website. Peter Mattis and Spencer Kimball wrote GIMP, and dozens of others have contributed plug-ins.

Editor’s note: For an insider’s look at GIMP, see Gonzalo León’s article in the Chapters Column.

Figure 2a Figure 2b
Figure 2c Figure 2d
Figure 2: This demonstrates several effects available in Graphics Workshop for Windows. Created by Amy Tse.

Graphics Workshop for Windows

Graphics Workshop for Windows by Alchemy Mindworks is an image management package that provides users with a way to view, print, convert and catalog images. Its strength is file conversion — it accepts more file formats than any of the other packages. While it does not have paint tools such as brush, text or fill, it does offer a full range of filters to fine tune photographs as well as options to flip, scale and crop images. Graphics Workshop for Windows provides an image database facility with keyword searching that allows a user to catalog images, associate keywords with those images and create arrays of thumbnails for later reference. Another feature is the slide show, which displays a series of images at full screen size at any user-specified transition speed. One of the more unusual features is the ability to take any text file and convert it into an image file that contains a picture of the text in its bitmap. The images in Figure 2 demonstrate some of the effects available in this package. Amy Tse created this figure.

Graphics Workshop for Windows requires 8 MB of disk space and runs on Windows 3.1, 95 and NT. It comes with on-line help and an electronic reference manual. Its cost is $40 and evaluation copies are available for download.

Figure 3: Created in NIH Image by Wendy Fischer.
Figure 3: Created in NIH Image by Wendy Fischer.

NIH Image/Scion Image

NIH Image was developed at the National Institute of Mental Health as an image processing and analysis program. Intended for work with CAT scans or with MRI, it can also be used as a means of creative expression. It features drawing tools (fill, draw, line, curves, air brush, text, etc.), filters for smoothing, sharpening, blurring and edge detection, and operations for flipping, rotating, inverting and scaling selected portions of an image. Layers can be emulated with stacks. A stack can contain up to 1,000 images called slices. The stack menu allows a user to order the slices and to select a slice for further editing. A user can adjust the transparency of images in the stack. Another menu option will animate the slices.

NIH Image uses a native file format that preserves the stacking information and imports TIFF, PICT and MacPaint files. It requires a color capatible Macintosh running System 7.0 or later and at least 4MB of RAM. For large stacks, having 32 MB of RAM is preferred. NIH Image is free and available for download. The software comes with a generous amount of documentation and an on-line help capability.

Recently, the Scion Corporation ported NIH Image to a Windows 95/NT platform and is offering it free of charge on their Web site. This version of the software requires Windows 95/NT with DirectX extensions. Scion recommends 32MB of RAM and a video card capable of displaying more than 256 colors.

For a taste of what NIH Image can do, see Figure 3. Wendy Fischer created this piece using NIH Image.

Figure 4: Created by Timothy Welch in Paint Shop Pro.
Figure 4: Created by Timothy Welch in Paint Shop Pro.

Figure 5a Figure 5b Figure 5c
Figure 5d Figure 5e Figure 5f
Figure 5g Figure 5h Figure 5i
Figure 5: This demonstrates various effects available through Webfx.

Rosalee Wolfe is an Associate Professor of Computer Science at DePaul University and teaches computer graphics and human-computer interaction. She has served on various SIGGRAPH committees since 1993 and has edited several Technical and Education Slide Sets.



Rosalee J.Wolfe
Department of Computer Science
AC 450
DePaul University
243 S.Wabash Ave.
Chicago, IL 60604

Tel: +1-312-362-6248
Fax: +1-312-362-6116


The copyright of articles and images printed remains with the author unless otherwise indicated.

Paint Shop Pro

Paint Shop Pro 5 by Jasc Software, is shareware that runs on Windows 95 or NT. In addition to airbrush, Paint Shop Pro features a wide set of drawing and painting tools, including brush types of marker, crayon, chalk and charcoal. It allows a user to choose from a set of preset brush textures as well as the opportunity to create new ones. The fill tool allows custom patterns as well as a variety of gradients in addition to the traditional solid fill. Digital photography techniques provide ways to blur, sharpen and emboss as well as dodging and burning images for proper exposure correction. There are filters to buttonize, erode and mosaic your image in addition to an option to create new animations from still images. It imports and exports over 40 file formats, including PICT, BMP, GIF, TIFF and JPG.

New in this version are layers. A user can adjust the opacity and stacking order of layers as well as the ability to group them together for further processing.

In order to run, Paint Shop Pro 5 requires a minimum of 12 MB RAM, 10MB of hard disk and a 486 running Windows 95/NT, but Jasc recommends a Pentium with MMX technology, 32 MB RAM and 40MB of disk space.

The purchase price is $99 and it is possible to download an evaluation copy from the Jasc Web site. The software comes with an extensive interactive Help capability, and Jasc has on-line support via the Internet. For Windows 3.1, Paint Shop Pro 3 provides most of the functionality of Paint Shop Pro 5 except for the layers feature. Its minimum requirements are a little less demanding as it needs only a 386 and 4MB RAM to operate. Its price is $69 and an evaluation copy is available on the Jasc Web site.

Timothy Welch used Paint Shop Pro to create the image in Figure 4.

Webfx

If you don’t have the time or inclination to download or install software, it is still possible to use dozens of exciting graphics filters to create dazzling images and animations. Bill Kendrick’s Webfx site provides a graphics manipulation tool that you can access over the Internet with your favorite browser without Java or additional plug-ins. You select an effect (Old Photo, motion blur, explode, etc.) and type in the URL of the image you want to change. In a few minutes, you see the results on your Web browser. You can save your new image for future use or you can use the option that allows you to email your creation. Some of the effects result in still images while others create animated GIF files. Figure 5 shows some of Webfx’s effects.

Conclusion

There are viable low-cost alternatives to expensive paint and image processing packages that are easily available on the Internet. Just as with higher-priced software, there are tradeoffs in functionality, ease of installation and price. In the hands of a student, however, all of them are capable for facilitating creative expression.