Keywords: front-page

# Window and Level Contrast Enhancement

[Laboratory]

An interactive contrast enhancement tool normaly available in image processing software is called Window and Level. It is a expansion of the contrast of the pixels within a given window range. Two parameters define the range: the middle point Level, and the width of the range Window. Another name for this operation is Intensity of Interest (IOI).

A graphic visualization of this process is shown below.

Window and Level Transfer Function

### Example

A practical application of this tool is given below. The original image is a CT Image with pixel values ranging from 1024 to 1862. The histogram plotted ranges from 1000 to 1862.

a)Original image; b)Its histogram
a) | b)

Applying the Window and Level technique with parameters `Window=100` and `Level=1100` yields

Window and Level contrast enhanced

- Lab: Window and Level Contrast Enhancement
- Other Examples