What is texture? The GLCM Texture Calculations Practical Notes More Information and References
What is texture?
Everyday texture terms - rough, silky, bumpy - refer to touch.
A texture that is rough to touch has:
- a large difference between high and low points, and
- a space between highs and lows approximately the same size as a finger.
Silky
would have
- little difference between high and low points, and
- the differences would be spaced very close together relative to finger size.
Image texture works in the same way, except
the highs and lows are brightness values (also called grey levels, GL, or
digital numbers, DN) instead of elevation changes. Instead of probing a finger
over the surface, a "window" - a (usually square) box defining the size of the
probe - is used.
Textures in images quantify:
- Grey level differences (contrast)
- Defined size of area where change occurs (window)
- Directionality or lack of it