BitmapDataExtensionsBeginAdjustContrast Method

Begins to adjust the contrast of the specified bitmapData asynchronously.

Definition

Namespace: KGySoft.Drawing.Imaging
Assembly: KGySoft.Drawing.Core (in KGySoft.Drawing.Core.dll) Version: 9.0.0
C#
public static IAsyncResult BeginAdjustContrast(
	this IReadWriteBitmapData bitmapData,
	float contrast,
	IDitherer? ditherer = null,
	ColorChannels channels = ColorChannels.Rgb,
	AsyncConfig? asyncConfig = null
)

Parameters

bitmapData  IReadWriteBitmapData
The IReadWriteBitmapData to be transformed.
contrast  Single
A float value between -1 and 1, inclusive bounds. Positive values increase the contrast, while negative values decrease the it.
ditherer  IDitherer  (Optional)
An optional IDitherer instance to dither the result of the transformation if the transformed colors are not compatible with the PixelFormat of the specified bitmapData. This parameter is optional.
Default value: .
channels  ColorChannels  (Optional)
The ColorChannels, on which the adjustment has to be performed. This parameter is optional.
Default value: Rgb.
asyncConfig  AsyncConfig  (Optional)
The configuration of the asynchronous operation such as parallelization, cancellation, reporting progress, etc. When Progress is set in this parameter, then this library always passes a DrawingOperation instance to the generic methods of the IAsyncProgress interface. This parameter is optional.
Default value: .

Return Value

IAsyncResult
An IAsyncResult that represents the asynchronous operation, which could still be pending.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type IReadWriteBitmapData. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).

Remarks

In .NET Framework 4.0 and above you can use also the AdjustContrastAsync method.

To finish the operation and to get the exception that occurred during the operation you have to call the EndAdjustContrast method.

This method is not a blocking call even if the MaxDegreeOfParallelism property of the asyncConfig parameter is 1.

  Tip

See the Remarks section of the AdjustContrast method for more details.

Exceptions

ArgumentNullExceptionbitmapData is .
ArgumentOutOfRangeExceptioncontrast is not between -1 and 1
-or-
channels is out of the defined flags.

See Also