public static FIBITMAP EnlargeCanvas<T>(
	FIBITMAP dib,
	int left,
	int top,
	int right,
	int bottom,
	Nullable<T> color,
	FREE_IMAGE_COLOR_OPTIONS options
)
where T : struct, new()

Public Shared Function EnlargeCanvas(Of T As {Structure, New}) ( _
	dib As FIBITMAP, _
	left As Integer, _
	top As Integer, _
	right As Integer, _
	bottom As Integer, _
	color As Nullable(Of T), _
	options As FREE_IMAGE_COLOR_OPTIONS _
) As FIBITMAP

public:
generic<typename T>
where T : value class, gcnew()
static FIBITMAP EnlargeCanvas(
	FIBITMAP dib, 
	int left, 
	int top, 
	int right, 
	int bottom, 
	Nullable<T> color, 
	FREE_IMAGE_COLOR_OPTIONS options
)

Type Parameters

Return Value

So, calling this function with all parameters left, top, right and bottom set to zero, is effectively the same as calling function Clone(FIBITMAP); setting all parameters left, top, right and bottom to value equal to or smaller than zero, my easily be substituted by a call to function Copy(FIBITMAP, Int32, Int32, Int32, Int32). Both these cases produce a new image, which is guaranteed not to be larger than the input image. Thus, since the specified color is not needed in these cases, color may be null.

Both parameters color and options work according to function FillBackground<(Of <(T>)>)(FIBITMAP, T, FREE_IMAGE_COLOR_OPTIONS). So, please refer to the documentation of FillBackground<(Of <(T>)>)(FIBITMAP, T, FREE_IMAGE_COLOR_OPTIONS) to learn more about parameters color and options. For palletized images, the palette of the input image is transparently copied to the newly created enlarged or shrunken image, so any color look-ups are performed on this palette.

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