---
title: "BrightnessContrast Class"
canonical: https://www.graphicsmill.com/docs/gm5/T_Aurigma_GraphicsMill_Transforms_BrightnessContrast.htm
product: "Graphics Mill 5.5 for .NET"
---

This documentation is for the old version. [Go to the latest Graphics Mill docs](https://www.graphicsmill.com/docs/gm/)

# BrightnessContrast Class
 
This class enables you to correct brightness and contrast of the image.
 
**Namespace:** [Aurigma.GraphicsMill.Transforms](https://www.graphicsmill.com/docs/gm5/N_Aurigma_GraphicsMill_Transforms.htm.md)
 **Assembly:** Aurigma.GraphicsMill (in Aurigma.GraphicsMill.dll)
 
## Syntax
  
```
Public NotInheritable Class BrightnessContrast _Inherits PerChannelBitmapTransform
```
 
```csharp
public sealed class BrightnessContrast : PerChannelBitmapTransform
```
 
## Remarks
 This class provides simple brightness and contrast adjustment functionality. Being extremely easy-to-use for end user, it is used by professional retouchers very seldom (because as usual it leads to losses of details in highlights and/or shadows). 
It provides two parameters - brightness modifier ([BrightnessAmount](https://www.graphicsmill.com/docs/gm5/P_Aurigma_GraphicsMill_Transforms_BrightnessContrast_BrightnessAmount.htm.md) property) and contrast modifier ([ContrastAmount](https://www.graphicsmill.com/docs/gm5/P_Aurigma_GraphicsMill_Transforms_BrightnessContrast_ContrastAmount.htm.md) property).

If you want to modify only brightness or contrast, you can use [Brightness](https://www.graphicsmill.com/docs/gm5/T_Aurigma_GraphicsMill_Transforms_Brightness.htm.md) or [Contrast](https://www.graphicsmill.com/docs/gm5/T_Aurigma_GraphicsMill_Transforms_Contrast.htm.md) transform. It will work slightly faster.
 
## Examples
  
```
Dim brightnessContrast As New Aurigma.GraphicsMill.Transforms.BrightnessContrast
brightnessContrast.BrightnessAmount = 0.2F
brightnessContrast.ContrastAmount = -0.1F
brightnessContrast.ApplyTransform(bitmap)
```
 
```csharp
Aurigma.GraphicsMill.Transforms.BrightnessContrast brightnessContrast = 
    new Aurigma.GraphicsMill.Transforms.BrightnessContrast();
brightnessContrast.BrightnessAmount = 0.2f;
brightnessContrast.ContrastAmount = -0.1f;
brightnessContrast.ApplyTransform(bitmap);
```
 
## Inheritance Hierarchy
  
- [System.Object](http://msdn2.microsoft.com/en-us/e5kfa45b)
    - [Aurigma.GraphicsMill.SyncHandler](https://www.graphicsmill.com/docs/gm5/T_Aurigma_GraphicsMill_SyncHandler.htm.md)
        - [Aurigma.GraphicsMill.UnitConverterHandler](https://www.graphicsmill.com/docs/gm5/T_Aurigma_GraphicsMill_UnitConverterHandler.htm.md)
            - [Aurigma.GraphicsMill.Transforms.BitmapTransform](https://www.graphicsmill.com/docs/gm5/T_Aurigma_GraphicsMill_Transforms_BitmapTransform.htm.md)
                - [Aurigma.GraphicsMill.Transforms.MaskedBitmapTransform](https://www.graphicsmill.com/docs/gm5/T_Aurigma_GraphicsMill_Transforms_MaskedBitmapTransform.htm.md)
                    - [Aurigma.GraphicsMill.Transforms.PerChannelBitmapTransform](https://www.graphicsmill.com/docs/gm5/T_Aurigma_GraphicsMill_Transforms_PerChannelBitmapTransform.htm.md)
                        - Aurigma.GraphicsMill.Transforms.BrightnessContrast
 
## Thread Safety
 Static members of this type are safe for multi-threaded operations. Instance members of this type are safe for multi-threaded operations.
  
## Supported Pixel Formats

| Member Name | Description |
| --- | --- |
| **Format8bppGrayScale** | 8 bits per pixel. Grayscale. 8 bits are used for luminosity level. |
| **Format16bppGrayScale** | 16 bits per pixel. Grayscale. All 16 bits are used for luminosity level (extended pixel format). |
| **Format16bppAGrayScale** | 16 bits per pixel. Grayscale with alpha channel. 8 bits are used for alpha channel and other 8 bits are used for luminosity level. |
| **Format32bppAGrayScale** | 32 bits per pixel. Grayscale with alpha channel. 16 bits are used for alpha channel and other 16 bits are used for luminosity level (extended pixel format). |
| **Format24bppRgb** | 24 bits per pixel. RGB. 8 bits each are used for the red, green, and blue components. |
| **Format32bppRgb** | 32 bits per pixel. RGB. 8 bits each are used for the red, green, and blue components. The rest 8 bits are unused. |
| **Format32bppArgb** | 32 bits per pixel. RGB with alpha channel. 8 bits each are used for the alpha, red, green, and blue components. |
| **Format48bppRgb** | 48 bits per pixel. RGB. 16 bits each are used for the red, green, and blue components (extended pixel format). |
| **Format64bppArgb** | 64 bits per pixel. RGB with alpha channel. 16 bits each are used for the alpha, red, green, and blue components (extended pixel format). |
| **Format32bppCmyk** | 32 bits per pixel. CMYK. 8 bits each are used for the cyan, magenta, yellow, and black components. |
| **Format64bppCmyk** | 64 bits per pixel. CMYK. 16 bits each are used for the cyan, magenta, yellow, and black components (extended pixel format). |
| **Format80bppAcmyk** | 80 bits per pixel. CMYK with alpha channel. 16 bits each are used for the alpha, cyan, magenta, yellow, and black components (extended pixel format). |
 
## See Also

### Reference

- [BrightnessContrast Members](https://www.graphicsmill.com/docs/gm5/AllMembers_T_Aurigma_GraphicsMill_Transforms_BrightnessContrast.htm.md)
- [Aurigma.GraphicsMill.Transforms Namespace](https://www.graphicsmill.com/docs/gm5/N_Aurigma_GraphicsMill_Transforms.htm.md)