### Contrast

The Contrast is a component build as wizard interface and implements methods to apply contrast enhancement on the selected bands of a raster.

Input:

- One Raster,
- A vector of bands indices where the contrast will be applied.

The available methods in Terralib are:

- Linear: The user defines a new minimum and maximum values for the pixels in the image. The algorithm then applies a linear function over the pixels using this 2 values.

- Histogram Equalization: Using this method, the histogram of the image will be equalized automatically.

- Set Mean and Standard Deviation: The contrasted image will have a predefined mean and standard deviation, defined by the user.

It is accessible through:
Layer Explorer > Right Click over a Layer-name > Raster Processing > Contrast... (applies on selected layer)
Raster Processing > Contrast... (list of all layers will be available)
This wizard consists of the following steps:

#### Wizard Page 1 - Selection of the layer with the desired raster (Layer Search).

NOTE: This page will only appear if the user has accessed the contrast operation from the menu "Raster Processing".

#### Wizard Page 2 - The contrast interface.

To execute this operation is required the following steps:

1. Select the type of contrast to be used,
2. Set specific parameters (the parameters will vary depending on the selected contrast type).
3. Preview (through the Check button).

#### Wizard Page 3 - Output information (Output Raster Information).

The result of this operation is shown in the figure below.