As seen in the previous lessons, Displacement Maps are powerful tools. In this tutorial, we use displacement
mapping and the Differences transfer mode to create a Moirépattern. This sort of manipulation creates
images that are beautiful in their own right. The sounds that result from such pictures are often a great
starting point for creating sound effects.

Step 1. Getting Started

A) With the Image Synth window in front, open the file "Tutorial5.presets", and choose the first preset:

B) Choose a displacement Map :
Double-click on the Displacement tool . The Displacement Map dialog box appears. Click on the pop-up menu's icon  to show the available displacement maps, and choose 
 
 
 
 

Step 2. Warping the Image
A) Click on the Displacement tool , and drag the mouse up and down until you are happy with the image.

B) Press  to smooth the image. The image will look something like this:

Step 3. Creating the MoiréPattern

MetaSynth provides a number of transfer modes which determine how an inserted selection will affect the underlying image.

A) Copy the image you just created by typing 'c' (or by choosing Copy Pict from the Image Synth's Edit Menu).

B) Insert the image by typing 'b' (Insert Pict).

C) Click on the the Transfer Mode tool  and choose Differences from the list of options.

NOTE: The image will momentarily seem to disappear. This is because in Differences mode the two images cancel each other when perfectly aligned.

D) Drag the image around and note the Moiré that appear as you move the picture.

Preset #3
TIP: With images such as this one, you will want to explore how the picture sounds in various tunings. Microtunings frequently give the best results.
 
 

IDEAS FOR FURTHER EXPLORATION:
You can get dramatic effects, by applying this process separately to the red and green channels of the image as we did for preset #4. (See Tutorial 7)

In Preset #5, we set the scale to be the first 64 harmonics of the harmonic series and applied some global
filters to the picture. The picture's duration was increased and the reference pitch set to E1.

Preset #5

The Substractive transfer mode can also yield useful results. For example, you might choose a preset. Copy
it (type "c"). Apply a filter to it. Insert the original preset (type "b"), and choose Subtractive from the
transfer mode pop-up menu, leaving only the pixels that were changed when the image was filtered.