ArtEffect 3.0 - graphics aftertreatment like Photoshop

So, this is now the third article about ArtEffect in the AmigaScene; there always are new versions of this beloved Image Processing program on the Amiga. This is naturally a positive sign in a time where one is always anxious if there will ever be new versions of Amiga programs.

This time it's about version 3.0, which compared to the previous 2.6 has no revolutionary changes or enhancements, but a few practical and useful new things, and it's these we want to cover in this article.

The program is delivered on four disks, and installation was without problem. The handbook is still that of version 1.1. All additional functions are completely covered in the installed AmigaGuide. Unfortunately, there's still no online help in the program itself, so the Help key is rather redundant. In any case, there are help bubbles which give a short tip on the various tools in the tools window when you move the mouse pointer over them.

A quick overview of image processing

Although we can't and won't go into an exhaustive introduction in image processing on the Amiga or ArtEffect specifics, for those that are interested but are not familiar with image processing programs, a short explanation of this topic.

The customary pixel-based paint programs - the best known is surely DPaint - is well understood by every Amiga user. Pictures are mainly drawn or painted with such programs. In their heyday, it was also a characteristic of these programs that there were only a limited amount of usable colours available on the screen simultaneously, due to the limitations of the hardware earlier used. Despite this shortcoming, talented artists could and can achieve quite astounding results with such programs, by careful colour selection and combination.

Later, as these colour limitations slowly disappeared with better graphic cards and greater computer memory capacity, paint programs with so-called "True Colour" came into being, that is, pictures that could be created with 65 thousand or 16 million colours. In contrast to "True Colour" painting programs the other is called "palette based", because they work with a so-called colour palette that represents a selection from the total available colours.

Once the colour limitations were lifted, further areas of use came into being. You were no longer required to draw everything by hand, but could suddenly very easily transfer photographs without any considerable quality loss into the computer. Naturally, there were unthought of possibilities. Naturally, pictures could later be very simply altered with True Colour paint programs. With True Colour pictures, you can accomplish entirely different operations rather than just a little painting around. You could, for example, colour correct specific areas, lighten, darken, retouch, etc. Everything that earlier only a photo laboratory could handle and much more is today be within the power of an image processing program. And now we have reached the theme. Image processing programs are specialized mainly for the manipulation of existing pictures. You can still paint freely with them, but most are used with pictures from various sources such as those scanned-in or photographs from a digital camera or artificially rendered pictures. You can, for example, repair damage in photos or composite elements from different pictures into a new one.

If you should now suddenly realize that for a long time an image processing program is just what you needed, or perhaps you would like to try for yourself what the author in the previous confusing sentences has tried to clarify, then simply download the demo version of ArtEffect from the Haage & Partner homepage.

Support for palette based pictures

A new feature has appeared in ArtEffect 3.0 that converts True Colour pictures down to greyscale or palette based pictures from 2 to 256 colours. An optional Floyd-Steinberg dithering routine to improve quality can be utilized. Other dithering routines are not supported however. Such palette based pictures can also be further processed in a restricted manner with ArtEffect. Simple operations such as mirroring, scaling and rotation are also possible. Most of the painting tools can also be used in a very limiting way with such pictures. Working with masks is in any case not possible with greyscale or palette based pictures.

This feature is especially useful when one needs a picture for the Internet. Such palette-based pictures can now be saved in GIF format, with a colour depth of 1 to 8 bits. Transparency is also supported.

Likewise, they can be saved either in ILBM(IFF) or PNG format. Only colour depths of 8 bits are used for these, which altogether doesn't seem to make much sense. If you have a picture that you have, for example, reduced down to 4 colours, then you should be able to save it as an ILBM with a colour depth of 2 bits (equals 4 colours). This should be something for the next version. In the meantime, this has to be accomplished with an external program.

Further possibilities with layers

Layers are a very useful feature. One can imagine these as clear plastic sheets that lie over each other in a certain order. Drawn elements on overlaying layers cover parts that lie underneath. A layer doesn't necessarily have to completely conceal underlying layers, as the layer itself and the colours applied to the layer has an adjustable opacity. Each layer can be modified and painted independently to each other. There is now no longer any artificial limitation on the number of layers. Naturally, there is a greater demand for memory for each additional layer. In addition, the demand for computer power increases. As well, it is now possible for drawing elements of overlaying layers to cast shadows on underlying layers. These shadows are automatically rendered, and can be switched on and off at any time, and the opacity and position of the shadow can be set as well. The layers can also be moved around against each other, and subsequent placement or shifting of picture elements that lie on different layers are possible at any time.

The brushes have a few more features

You can vary the size of the brush dependent on pressure (especially interesting for pressure sensitive graphic tablets) or randomly during painting. The defined sized is the maximum size, which becomes smaller as pressure is reduced. The minimum size can be set as a percentage of maximum (100%), which determines the intensity of the size variations.

A further effect of the new brushes is the possibility to set a specific spray behaviour. This means the colour pixels won't necessarily be applied under the tip of the mouse pointer, as is normally done, but randomly within an adjustable radius. This is the same effect as the spay can in the paint program DPaint.

New in filters

Of course the filter modules, with which one carries out different effects and changes to the image, have been expanded and improved. A new addition is the deinterlace filter. With the two fields you get from a freeze-frame of a video picture, a flickering picture will be seen with moving scenes. This situation is caused by the interlace sequence, which is used in television. The flickering pictures are always only either the odd or even lines being displayed. Every second line is skipped. Because of the movement of the displayed object between the two fields, you get two slightly different pictures over each other. The deinterlace filter generates a new picture from either the odd or even lines without the flickering. It is not simply that every second line is just left out and replaced by the neighboring line, but an interpolation between both the fields is performed.

In addition, the caricature and gaussian filters are now faster and have new options.

Improvements with graduated colours

Art Effect now lets you define very nice colour graduations. You can set the colour value as well as transparency. To set this, you basically have a frame which represents the whole graduation, in which various keypoints are defined that have a specific colour value assigned to them. An example of such a graduation is included with Art Effect, "the Rainbow". This is accomplished using the key colours red, yellow, green, cyan, blue and magenta. The position of the key points can be changed at any time, and numerical entry of the positions are also planned.

Transparency can be set by the same procedure with an alternate frame.

Internal improvements of version 3.0

There aren't only new functions, but also improvements in the program itself. There are reduced memory requirements, which can be a deciding factor with the use of many layers. Also the refresh operation has been changed and is performed asynchronously to drawing.

Summary

The program gives all in all a very stable and practicable impression. However, my tests with scaling a greyscale picture seemed sometimes an endless operation.

To some extent you must have a computer with an MC68060 processor and plenty of memory for any serious work. Also a fast harddisk is advisable, as virtual memory is used due to the program's high memory demands, where data always has to be exchanged between the harddisk and memory.

Useability
Features
Quality
Value 4 Money
Stability
Documentation
Overall

Thomas Öllinger
Steve Bowman

ArtEffect screen (GIF; 105K)

gradient manager (GIF; 8K)

brush settings (GIF; 6K)