interface IImage in Tinman.Terrain.Imaging

The IImage interface is the basis of the Imaging Object Model.

interface	IImage	extends	IConfigurable
			IEquatable<IImage>
			IImageOps<IImage>
		base of	Image

Remarks

The Imaging Object Model can be used to generate image data from a variety of different input sources using transformations. All transformations, conversions, etc. are performed on-the-fly while an image is being read, scanline after scanline. This allows efficient processing of extremely large images, since buffers and temporary storage space is only necessary for a couple of scanlines.

Methods

Adjust

Adjust the brightness and saturation of this image.

[OwnerReturn, OwnerThis]
method	Adjust (int32 brightness, int32 saturation = 0)
type	T
params	brightness	[-1000..1000]	The adjustment factor for image brightness.
	saturation	[-1000..1000]	The adjustment factor for image saturation. Defaults to 0.
returns		[not-null]	The resulting image.
inherited	IImageOps.Adjust

See also:

Colors.Adjust

Background

The image scanlines will be read using concurrent background tasks.

[OwnerReturn, OwnerThis]
method	Background ()
type	T
returns		[not-null]	The resulting IImageReader object.
inherited	IImageOps.Background

ChannelToIntensity

Returns an opaque grayscale image which pixel values are equal to the given pixel channel of this image.

[OwnerReturn, OwnerThis]
method	ChannelToIntensity (PixelChannel channel)
type	T
params	channel		The pixel channel.
returns		[not-null]	The resulting image.
inherited	IImageOps.ChannelToIntensity

Remarks:

Void pixels in this image will also be void in the resulting image.

See also:

IImageOps.IntensityToChannel

Clip

Returns an image that represents a sub rectangle of this image.

[OwnerReturn, OwnerThis]
method	Clip (int32 x, int32 y, int32 width, int32 height)
type	T
params	x	[>=0]	X-coordinate of top-left corner of rectangle.
	y	[>=0]	Y-coordinate of top-left corner of rectangle.
	width	[>0]	Width of rectangle.
	height	[>0]	Height of rectangle.
returns		[not-null]	The resulting image.
inherited	IImageOps.Clip

Crop

Assumes the image holds a non-rectangular shape that is padded with a uniform color and replaces all padding pixels with void.

[OwnerReturn, OwnerThis]
method	Crop (int64 color = Colors.Black, int32 skip = 1)
type	T
params	color		The padding pixel color (see Colors). Defaults to Black.
	skip		The maximum length (in pixels) of a run surrounded by void pixels that will be interpreted as void, too. Defaults to 1.
returns		[not-null]	The resulting image.
inherited	IImageOps.Crop

Remarks:

Since the source image is read scanline after scanline, cropping is performed locally for each scanline: Beginning at the left and right image borders, all pixels having the same color as the color parameter are replaced with void until a consecutive run of pixels having different colors is found (see skip). The following figures illustrates this: Pixels that have the same color as the color parameter are shown as '.' characters, all others are indicated with X:

+-----------------------------------------------------------------------+
|.......................................................................|
|.......................................................................|
|............................XXX........................................|
|...........................XXXXX.......................................|
|.........................XXXXXXX.......................................|
|.......................XXXXXXXXX.......................................|
|.....................XXXXXXXXXXX.......................................|
|...................XXXXXXXXXXXXXX......................................|
|.................XXXXXXXXXXXXXXXX......................................|
|................XXXXXXXXXXXXXXXXX......................................|
|...............XXXXXXXXXXXXXXXXXXX.....................................|
|................XXXXXXXXXXXXXXXXXXX....................................|
|.................XXXXXXXXXXXXXXXXXXXXX.................................|
|...................XXXXXXXXXXXXXXXXXXXXXXX.....X.......................|
|...............XXXXXXXXXX..XXXXXXXXXXXXXXXXXXXXXXXXXXX.................|
|..........XXXXXXXXXXXX.......XXXXXXXXXXXXXXXXXXXXXXXXXXX...............|
|.............XXXXXXX..........XXXXXXXXXXXXXXXXXXXXXXXXXX...............|
|...............XXX.............XXXXXXXXXXXXXXXXXXXXXXXX................|
|................................XXXXXXXXXXXXXXXXXXXXX..................|
|................................XXXXXXXXXXXXXXXXX......................|
|...................................XXXXXXX.............................|
|.......................................................................|
|.......................................................................|
|.......................................................................|
|.......................................................................|
+-----------------------------------------------------------------------+

The cropped image will look like this (whitespace represents void pixels):

+-----------------------------------------------------------------------+
|                                                                       |
|                                                                       |
|                            XXX                                        |
|                           XXXXX                                       |
|                         XXXXXXX                                       |
|                       XXXXXXXXX                                       |
|                     XXXXXXXXXXX                                       |
|                   XXXXXXXXXXXXXX                                      |
|                 XXXXXXXXXXXXXXXX                                      |
|                XXXXXXXXXXXXXXXXX              cropped because         |
|               XXXXXXXXXXXXXXXXXXX             of skipped pixels       |
|                XXXXXXXXXXXXXXXXXXX            |                       |
|                 XXXXXXXXXXXXXXXXXXXXX         V                       |
|                   XXXXXXXXXXXXXXXXXXXXXXX                             |
|               XXXXXXXXXX..XXXXXXXXXXXXXXXXXXXXXXXXXXX                 |
|          XXXXXXXXXXXX.......XXXXXXXXXXXXXXXXXXXXXXXXXXX               |
|             XXXXXXX..........XXXXXXXXXXXXXXXXXXXXXXXXXX               |
|               XXX.............XXXXXXXXXXXXXXXXXXXXXXXX                |
|                         ^      XXXXXXXXXXXXXXXXXXXXX                  |
|                         |      XXXXXXXXXXXXXXXXX                      |
|                  not reachable    XXXXXXX                             |
|                  from left or                                         |
|                  right border                                         |
|                                                                       |
|                                                                       |
+-----------------------------------------------------------------------+

Cropping will not change the image size or modify the georeference.

Function

Transform linear pixel values using a custom function.

[OwnerReturn, OwnerThis]
method	Function (string function, PixelChannel channel = PixelChannel.Intensity)
type	T
params	function	[not-null]	A function expression (see GrammarRuleExpression) that consumes input linear pixel values in the range [0..1] and returns output linear pixel value in the range [0..1]. Output values are clamped (including infinities), not-a-number output values produce void pixels (see Void).
	channel		The pixel channel the function shall be applied to. If Void, no transformation will be performed. Defaults to Intensity.
returns		[not-null]	The resulting image or this if channel is Void.
inherited	IImageOps.Function

Remarks:

The given function is evaluated on linear pixel values, that is after raw pixels have been translated to normalized pixel values (see SetRange) and after gamma correction has been applied (see SetGamma). The expression may use all members of the default Tinman script (see Tinman). The following arguments are available to the function expression:

• raw
  The input pixel value (raw).
• lin
  The input pixel value (linear) in the range [0..1].
• A, B, C, D, E, F
  Coefficients that can be used to transform between raw and linear pixel values:

  lin = pow(raw * A + B, C)
  raw = pow(lin, D) * E + F
  D   = 1 / C
  E   = 1 / A
  F   = -B / A

  where raw is the raw pixel value that is actually stored in the source image (e.g. [0..255] for 8-bit images) and lin is the linear pixel value that is stored in the image scanline buffer (see Scanline). A and B represent the transformation from raw pixel values to normalized pixel values (see SetRange); C is the exponent that best approximates the performed gamma correction (see SetGamma).

IntensityToChannel

Returns an image that has a single pixel channel (see channel parameter), initialized to the grayscale intensities of this image. All other pixel channels are initialized to their respective default values (see PixelChannel).

[OwnerReturn, OwnerThis]
method	IntensityToChannel (PixelChannel channel)
type	T
params	channel		The pixel channel.
returns		[not-null]	The resulting image.
inherited	IImageOps.IntensityToChannel

Remarks:

Void pixels in this image will also be void in the resulting image.

See also:

IImageOps.ChannelToIntensity

---

Replaces a pixel channel of the given image with the grayscale intensities of this image.

[OwnerReturn, OwnerThis]
method	IntensityToChannel (PixelChannel channel, [Owner] T image)
type	T
params	channel		The pixel channel to replace.
	image	[not-null]	The image which pixel channel is to be replaced.
returns		[not-null]	The resulting image.
inherited	IImageOps.IntensityToChannel

Remarks:

Void pixels in the other image are ignored (i.e. the original pixel remains unchanged). Void pixels in this image are preserved (i.e. the other pixel is ignored).

See also:

PixelChannel

Invert

Inverts the given pixel channel.

[OwnerReturn, OwnerThis]
method	Invert (PixelChannel channel)
type	T
params	channel		The pixel channel.
returns		[not-null]	The resulting image.
inherited	IImageOps.Invert

Remarks:

The Void pixel channel cannot be inverted. The method will do nothing in this case.

Op

Combines this image (first) with the given one (second) using the specified color operation (see ColorOp).

[OwnerReturn, OwnerThis]
method	Op ([Owner] T other, ColorOp colorOp)
type	T
params	other	[not-null]	The other image.
	colorOp		The color operation to apply.
returns		[not-null]	The resulting image.
inherited	IImageOps.Op

Pad

Pads this image by duplicating pixels at the borders.

[OwnerReturn, OwnerThis]
method	Pad (int32 amount = 1)
type	T
params	amount	[>=0]	The pad amount, in pixels. Defaults to 1.
returns		[not-null]	The resulting image.
inherited	IImageOps.Pad

Remarks:

Padding can be used to reduce seams that will occur when tiled geodata is imported incrementally using on-the-fly projection. The correct solution would be to merge all geodata tiles into a dataset and then perform the projection on the whole geodata.

ReadImage

Creates an IImageReader object that reads the image data of this image.

[OwnerReturn]
method	ReadImage (ReadImageFlags flags = ReadImageFlags.Data)
type	IImageReader
params	flags		The read flags to use. Defaults to Data.
returns		[not-null]	The IImageReader object.

Exceptions:

• TinmanException:
  If the image descriptor is incomplete.

ReadImageInfo

Returns information about the image.

method	ReadImageInfo (ReadImageFlags flags = ReadImageFlags.Info)
type	IImageInfo
params	flags		The read flags to use. Defaults to Info.
returns		[not-null]	An ImageInfo object that holds information about the image.

Exceptions:

• GeorefException:
  If the image contains unsupported georeferencing metadata.
• TinmanException:
  If the image descriptor is incomplete.

ReadTexture

Reads this image as a texture.

[OwnerReturn]
method	ReadTexture (CubemapFace face = CubemapFace.NegZ, TextureFormat format = null, bool srgb = true)
type	TexelBuffer
params	face		The cubemap face to read. Set to NegZ for 2D textures. Defaults to NegZ.
	format		The texture format to use, if not specified by the file format. If null, the texture format will be determined from the pixel format (see For), if necessary. Defaults to null.
	srgb		The Srgb flag to use when pixels need to be encoding into texels. Will be ignored if the file format already contains encoded texels. Defaults to true.
returns			The read texture or null if the given cubemap face does not exit.

Scale

Returns an image that represents a scaled version of this image.

[OwnerReturn, OwnerThis]
method	Scale (int32 width, int32 height, InterpolationMode mode = InterpolationMode.UniformB)
type	T
params	width	[>0]	Width of the scaled image.
	height	[>0]	Height of the scaled image.
	mode		The interpolation mode to use for magnification. Defaults to UniformB.
returns		[not-null]	The resulting image.
inherited	IImageOps.Scale

SetCoverage

Updates the value of Coverage, without modifying the image content.

[OwnerReturn, OwnerThis]
method	SetCoverage (PixelCoverage coverage)
type	T
params	coverage		The pixel coverage.
returns		[not-null]	The resulting image.
inherited	IImageOps.SetCoverage

Remarks:

To perform resampling between pixel-is-area and pixel-is point, use ToCoverage.

SetGamma

Updates the value of Gamma.

[OwnerReturn, OwnerThis]
method	SetGamma (float64 gamma)
type	T
params	gamma		The gamma correction.
returns		[not-null]	The resulting image.
inherited	IImageOps.SetGamma

SetGeoref

Updates the value of Georef, without modifying the image content.

[OwnerReturn, OwnerThis]
method	SetGeoref (Raster georef)
type	T
params	georef		The georeferencing information or null.
returns		[not-null]	The resulting image.
inherited	IImageOps.SetGeoref

SetLayer

Updates the value of Layer, without modifying the image content.

[OwnerReturn, OwnerThis]
method	SetLayer (HeightmapLayer layer, PixelFormat format = PixelFormat.Unknown)
type	T
params	layer		The heightmap layer.
	format		The pixel format to use for choosing the heightmap format (see For). If Unknown, the pixel format of this image will be used. Defaults to Unknown.
returns		[not-null]	The resulting image.
inherited	IImageOps.SetLayer

SetNoData

Updates the value of NoData.

[OwnerReturn, OwnerThis]
method	SetNoData (float64 noData)
type	T
params	noData		The raw pixel value to map to void pixels (see NoData).
returns		[not-null]	The resulting image.
inherited	IImageOps.SetNoData

SetRange

Updates the value of Range.

[OwnerReturn, OwnerThis]
method	SetRange (PixelRange range, bool reinterpret = false)
type	T
params	range		The pixel value ranges to use for translating raw pixel values to normalized pixel values (see Range).
	reinterpret		true to leave raw pixels values unchanged and reinterpret them according to range, false to normalize raw pixel values to range. Defaults to false.
returns		[not-null]	The resulting image.
inherited	IImageOps.SetRange

Sharpen

Performs sharpening on this image.

[OwnerReturn, OwnerThis]
method	Sharpen (IImage detail, float32 scale = 1, int32 downsample = 4)
type	T
params	detail	[not-null]	The high-resolution detail image to use for sharpening.
	scale	[>=0]	Scale factor to apply to difference between full and reduced resolution. Defaults to 1.
	downsample	[>0]	The detail image will be downsamples by this factor. The difference between the full and reduced resolutions will be used to sharpen this image. Defaults to 4.
returns		[not-null]	The resulting image.
inherited	IImageOps.Sharpen

Smooth

Performs smoothing on this image.

[OwnerReturn, OwnerThis]
method	Smooth ()
type	T
returns		[not-null]	The resulting image.
inherited	IImageOps.Smooth

Remarks:

Image smoothing is performed using an Uniform-B spline.

ToConfig

Returns the configuration value that describes this object.

method	ToConfig ()
type	ConfigValue
returns		[not-null]	The configuration value.
inherited	IConfigurable.ToConfig

Remarks:

All configurable objects need to implement this interface. For simple types, it is preferable to delegate to ToValue.

The returned value may be of type Invalid, which means that this object in its current state cannot be described with the configuration API.

Before returning the resulting configuration value, Cache must be called on it, passing this IConfigurable object as parameter.

ToCoverage

Transforms this image from the given pixel coverage semantic to the given one.

[OwnerReturn, OwnerThis]
method	ToCoverage (PixelCoverage target, bool wrapX = false)
type	T
params	target		The pixel coverage semantic of the resulting image.
	wrapX		Is this image wrapped around the X-axis?
returns		[not-null]	The resulting image.
inherited	IImageOps.ToCoverage

Remarks:

If this image already has the given pixel coverage semantic, no transformation will be performed.

Write

Outputs the pixels of this image via the given image writer.

[OwnerReturn]
method	Write ([Owner] IImageWriter writer, bool geo = true)
type	IOperation
params	writer	[not-null]	The image writer to use.
	geo		When set to true, the Geo flag will be used when reading this image, iff HasGeoref also returns true. Otherwise, the flag will not be used. Defaults to true.
returns		[not-null]	The background operation.

Extensions

ImportPixels

Returns an operation that imports image pixels into a PXB image file or a rectangular HGT heightmap dataset.

[OwnerReturn]
method	ImportPixels (Path path = null)
type	IOperation
params	path		Output path of image or dataset file. If null, the file path of input will be used, having the file suffix replaced with .pxb resp. .hgt. Defaults to null.
returns		[not-null]	The import operation.

Remarks:

The output format can be chosen by using the corresponding file suffix for the path parameter. If no path is given, a heightmap dataset will be created if the Layer of the input image has been set (i.e. it has a value other than None).

ProjectPixels

Returns an operation that projects image pixels onto a cubemap HGT heightmap dataset.

[OwnerReturn]
method	ProjectPixels ([Owner] IHeightmap output, IMapProjectionFactory projection = null)
type	IOperation
params	output	[not-null]	The output heightmap dataset.
	projection		The map projection to use. If null, the projection is derived from available georeferencing information. Defaults to null.
returns		[not-null]	The operation.

WriteFile

Outputs the pixels of this image to the given image file.

[OwnerReturn, OwnerThis]
method	WriteFile (Path imageFile)
type	IOperation
params	imageFile	[not-null]	The image file to write.
returns		[not-null]	The background operation.

Remarks:

The image file format will be determined from the file suffix (see CanWrite).