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Free/shareware Image Manipulation programmes for the Apple Macintosh.

Alan Leavy. IT Coordinator. Loughborough College of Art and Design

Programmes reviewed
Escher Draw (Freeware)
Colour Knit (Shareware $15)
Imagic (Freeware)
GreyStation (30UKP)

Since Apple introduced the Mac 128k and included MacPaint with the deal, many programmers have designed alternative drawing, painting and image manipulation programmes that are either free or shareware. In some cases the programmes have been labours of love and dedication that have provided a cheap and effective alternative to the cornmercial tools such as Adobe Photoshop and Letraset Painter. In other cases, the programme has filled a niche requirement that is not available commercially.

This case study examines four freely available programmes that attempt to solve typical image-related problems in a cheap if not necessarily, cheerful manner.


A small programme of 99k, that offers repetitive pattern designing in black and white. Escher Draw would be useful to students studying textile- design or fashion who wish to.develop, or experiment with, simplistic, repeating designs. The programme is simple to use and offers only a few basic features of pattern designing which is used in conjunction with a chosen symmetry from a list of 17. These Above: The main drawing window showing the include parallelogram, square, hexagonal and rectangle. The user chooses a symmetry and draws using a basic, one width tool, on a given pattern size. As the drawing continues, the pattern is repeated to show the development of the overall design. The user may edit at any stage. There are some limitations of Escher Draw, notably the inability to apply a symmetry to a design 'after-the-event' This narrows any free-form or happy-accident creative potential. The prograrnmer also admits to the print feature being a bit buggy and suggests saving all work before printing!

The bottom line

For people looking for repetitive design on the cheapest possible budget - free! - Escher Draw might be what you're after. Used in conjunction with a colour paint programme such as Imagic (reviewed later) that allows importing of patterns from Escher Draw and subsequent colour adaptions, the designer would have the basis of a useful and quick pattern generation facility.

Escher Draw Vl.0 by Wam Development. Available via anonymous ftp from a number of Mac ftp sites.


Another one for the textile designers !

On running this programme one is presented with what seems a simplistic, painting-by-squares drawing programme. However, Colour Knit provides comprehensive facilities for textile and knitting pattern designers that don't seem to be covered by commercially available programmes - at this cost anyway !

Paul Duffy a weaver and the pr~ ie of Colour Knit has provides features for colour choice, knit gauge and weave style as well as providing the ability to 'evolve' a design in an organic manner similar to the game of Life that many older users of computers will be familiar with. The programme is very stable and ran happily on colour Mac's from Mac II to the new Performa 630.

As can be seen from the examples, the user has a variable grid that can be set up for all common stitch gauges and a bar that offers simple drawing tools. Part of the tool bar is used to 'push' the grid around and to reflect or mirror the image. A help menu is also available direct from the tool bar as well as the comprehensive text file supplied with the programme. Brush size is variable and there are three palletes of colour to experiment with as well as the ability to choose your own colour ways. Colour Knit works well with other programmes and uses the common Pict file method for transferring images. There is also a useful preview feature.

The bottom line

For the student of textile or knitting design, or the professional working to a tight budget, Colour Knit might present you with an opportunity for quick mock-ups or visualisation of projects that traditionally might take longer. The bonus is the ability to evolve and mature designs 'on-the-fly' and this feature could provide inspiration that is not possible when working with pencil and graph paper.

Colour Knit V3.0 by Paul Duffy. Available via anonymous ftp from a number of Mac ftp sites.


Ok. So you can't afford Photoshop and it's too complex anyway. And all you want to do is some retouching of a colour photograph. Maybe you're a geography or physics student who wishes to manipulate the colour balance of some surface temperature scans to bring out some hidden detail. Well this is for you !

The Features

From this list you'll see that Imagic has been given the right kind of name. However, it's not really the kind of programme that you might choose for photo-retouching as in many ways it' s power is best used in a scientific or technical project where interpretation of an existing image is called for. Imagic allows many types of interpretation to be applied to images. One of the most useful is the prograrnmes ability to change the colour balance and colour table. This can bring out hidden features or emphasise difficult to see areas of an image. These different areas of the image can be checked for density and then labelled. A quick density graph can also be obtained and presented - the density relating to the colour value in the range 0 - 255.

There are basic drawing and selecting tools and these can be useful for making minor amendments to photographs and the enhancement menu can provide the means to increase contrast or polarise an image.

Imagic can import and export in three formats: pict, image and raw format. Raw might be useful for users working on types of platform other than the Mac. Additionally, there are External Functions that can be used to write your own Imagic functions and if you know how to programme in C, then documentation is included in the package. Also, a Save Selection as Text. . . command has been included in the File Menu. When you make a selection, you may save the pixel values out as an Excel text file. This allows you to take your data and put it into the Spreadsheet for direct calculations if you're that way inclined.

The bottom line

Imagic is a powerful tool that has developed over time into a scientifically-oriented programme suitable for image enhancement but it also has features that would be useful to designers who wish to experiment with particular kinds of image manipulation or three-dimensional imaging. The addition of a Macro feature for repeating often-used steps speeds up the use of the programme and Imagic's ability to use many colour taLbles is a major feature for geographers and physicists.

Imagic by Brian Powell V0.9 Available via anonymous ftp from a number of Mac ftp sites.


This programme is fairly new and with it's sister programme Colour Station, provides high-quality, cost-effective, mono and colour image editing for the amateur or professional designer. The illustrations show the straightforward and modern 3D interface that control many features of the programme.

Editing and retouching of images is controlled through the simple, iconic toolbar that allows pixel-based editing, painting of larger areas, filling with greyscale colour, air brushing and deletion. Also incorporated are basic drawing tools and effective selection and type toc ls. Each of the tools has a 'hidden' parameter control panel accessed by double-clicking the tool. The programme is quick when selecting contiguous areas with the magic wand and this particular tool has very fine control over the tvpe of area to be selected.

Grey Station comes into it's own when printing to postscript printers. There are controls for calibrating specific printers by printing grey,scale test strips and the programme has it's own methods of dithering images to obtain the highest quality printing from the average LaserWriter or image setter.

The bottom line

For day-to-day, grey-scale, pixel-level editing that is quick and provides a good quality printing facility, Grey Station is fine for the job. For those people who want image manipulation and/or contrast controls look to alternative programmes such as Imagic.

Grey Station by Le Pixel Available via anonymous ftp from a number of Mac ftp sites.


This case-study covers only a few of the many free or shareware image-manipulation programmes available for the Mac. Apologies if I've left out your favourite one or you're a Windows or DOS user.

I'm sure that with the advent and development of the 'super' programmes like Photoshop, Illustrator and Xpress, there is room for individual developers and programrners to fill the niche areas of design that are often overlooked by the big boys in their moves to cover the more popular and commercial vertical markets.

Without the likes of Imagic and Colour Knit the potential users of these programmes would be left out in the cold or have to revert to expensive commercial programmes dlat might require another platform to run on. If you use these programmes- or others - support your 'local' developer and pay the shareware fee or send a note of gratitude if you liked the programme.

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