BitmapDataExtensionsBeginAdjustContrast Method

public static IAsyncResult BeginAdjustContrast(
	this IReadWriteBitmapData bitmapData,
	float contrast,
	IDitherer? ditherer = null,
	ColorChannels channels = ColorChannels.Rgb,
	AsyncConfig? asyncConfig = null
)

<ExtensionAttribute>
Public Shared Function BeginAdjustContrast ( 
	bitmapData As IReadWriteBitmapData,
	contrast As Single,
	Optional ditherer As IDitherer = Nothing,
	Optional channels As ColorChannels = ColorChannels.Rgb,
	Optional asyncConfig As AsyncConfig = Nothing
) As IAsyncResult

public:
[ExtensionAttribute]
static IAsyncResult^ BeginAdjustContrast(
	IReadWriteBitmapData^ bitmapData, 
	float contrast, 
	IDitherer^ ditherer = nullptr, 
	ColorChannels channels = ColorChannels::Rgb, 
	AsyncConfig^ asyncConfig = nullptr
)

[<ExtensionAttribute>]
static member BeginAdjustContrast : 
        bitmapData : IReadWriteBitmapData * 
        contrast : float32 * 
        ?ditherer : IDitherer * 
        ?channels : ColorChannels * 
        ?asyncConfig : AsyncConfig 
(* Defaults:
        let _ditherer = defaultArg ditherer null
        let _channels = defaultArg channels ColorChannels.Rgb
        let _asyncConfig = defaultArg asyncConfig null
*)
-> IAsyncResult 

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 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

Usage Note

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.

Reference