# Image Analysis and Processing for Generating Camouflages from Digital Earth Photographs
## 2 Selected Practical Aspects of Camouflage
### Design Classification  
Color camouflages use various phenomena to achieve the desired effect. Some of them break the silhouette of the object well, and others make the object blend in with the surroundings. They can also use different techniques, e.g., some camouflages use geometric shapes, and others use overlaid photos of vegetation or the ground. Due to these differences, the camouflages can be classified as follows [4; 5; 8]:  
* Mimetic--usually made up of small spots to make the object resemble its surroundings, which naturally consists of a noise of various colors. These spots are used to make  
Figure 1: Example of color camouflage—a tank without camouflage on the **left**, camouflage on the **right**[6].  
Figure 2: Example of vegetal camouflage—grass camouflage [6].  
the object similar to a given color noise occurring in a given area. There is a micro- and macro-pattern in mimetic patterns. The camouflages presented in Figure 3 are an example of German mimetic camouflages from the times of the Second World War.
* Deformational--composed of overlapping geometries of soft, natural, or sharp geometric shapes. Camouflages of this type are very effective at longer distances, because large shapes do not merge into one color.
* Pixel/Digital--currently the most popular type of camouflage. Its pattern is built by pixels filled with appropriate colors. The principle of operation is similar to the mimetic camouflage; it also has a micro- and macro-pattern. The camouflage shown in Figure 4 is one of the first digital camouflages.  
The _micro-pattern_ is a composition of small spots that can be distinguished only when viewed from close range [4; 5; 6]. The role of this type of pattern is to hide the object from spatial vision, i.e., the area where the observer does not focus the pattern and thoughts. The micro-pattern makes the camouflaged object blend into its environment through carefully selected small shapes and colors that are similar to the natural noise of colors found in nature. It is ideally suited to hide from spatial vision. Figure 5 presents an example scale of micro-pattern. An example of a micro-pattern is shown in Figure 3, where the camouflage is made up of a large number of small spots, i.e., a micro-pattern. In addition, it can be observed in Figure 4, where it appears as small spots that merge into larger lumps.  
Figure 4: Examples of pixel camouflages: MARPAT on the **left**, CADPAT on the **right**[6].  
Figure 3: Example of Zeltbahn mimetic camouflage in spring (**left**) and autumn (**right**) versions [8].  
The _macro-pattern_ is a large stain designed to break the shapes of camouflaged objects. Its role is mainly to influence central vision, focused on finding shapes. When an object is spotted through spatial vision, the observer will focus on it and try to identify the object by recognizing the shape of the shadows as well as the lines of symmetry. The right macro-pattern is able to confuse the observer's eyesight, who will not be able to match it with the appropriate pattern, and may inadvertently consider it as unimportant, which will lead to the target not being detected. Figure 6 shows an example of macro-pattern deforming a human silhouette.