GifEncoderEncodeHighColorImage Method

public static void EncodeHighColorImage(
	IReadableBitmapData imageData,
	Stream stream,
	bool allowFullScan = false,
	Color32 backColor = default,
	byte alphaThreshold = 128
)

Public Shared Sub EncodeHighColorImage ( 
	imageData As IReadableBitmapData,
	stream As Stream,
	Optional allowFullScan As Boolean = false,
	Optional backColor As Color32 = Nothing,
	Optional alphaThreshold As Byte = 128
)

public:
static void EncodeHighColorImage(
	IReadableBitmapData^ imageData, 
	Stream^ stream, 
	bool allowFullScan = false, 
	Color32 backColor = Color32(), 
	unsigned char alphaThreshold = 128
)

static member EncodeHighColorImage : 
        imageData : IReadableBitmapData * 
        stream : Stream * 
        ?allowFullScan : bool * 
        ?backColor : Color32 * 
        ?alphaThreshold : byte 
(* Defaults:
        let _allowFullScan = defaultArg allowFullScan false
        let _backColor = defaultArg backColor new Color32()
        let _alphaThreshold = defaultArg alphaThreshold 128
*)
-> unit 

Parameters

imageData  IReadableBitmapData

The image data to write. Possible alpha pixels might be blended with backColor but otherwise the color depth will be preserved.

stream  Stream

The stream to save the encoded animation into.

allowFullScan  Boolean  (Optional)

to allow scanning the whole image for each layers to be able to re-use the local palette of the current layer.
to expand the initial layer area to the local pixels only. This parameter is optional.
Default value: .

backColor  Color32  (Optional)

Colors with alpha (transparency), whose Color32.A field is equal to or greater than alphaThreshold will be blended with this color during the encoding. The alpha value (Color32.A field) of the specified background color is ignored. This parameter is optional.
Default value: The default value of the Color32 type, which has the same RGB values as Black.

alphaThreshold  Byte  (Optional)

Specifies a threshold value for the Color32.A field, under which a pixel is considered transparent. If 0, then the final composite image will not have transparent pixels. This parameter is optional.
Default value: 128.

If allowFullScan is , then both the processing time and memory usage is higher. It helps to minimize the number of layers of the final image; however, the final image size will not be necessarily smaller, especially for true color images.

If allowFullScan is , then each layer is attempted to be as compact as possible. It allows a very fast processing with lower memory usage. Though it usually produces more layers, the final size will not be necessarily larger, especially for true color images.

To encode an Image you can use also the ImageExtensions.SaveAsHighColorGif methods.

To create a multi-layered image completely manually you can create a GifEncoder instance that provides a lower level access.

Reference