Class DecodedRasterImage

Namespace

DocWright.Core.Imaging

Assembly

DocWright.Core.dll

A decoded raster image in a renderer-neutral form: interleaved 8-bit colour samples plus an optional 8-bit alpha plane.

public sealed class DecodedRasterImage

Inheritance

object

DecodedRasterImage

Inherited Members

object.GetType()

object.ToString()

object.Equals(object)

object.Equals(object, object)

object.ReferenceEquals(object, object)

object.GetHashCode()

Remarks

Colour and alpha are kept in separate planes rather than interleaved as RGBA because that is what a PDF image XObject needs — the alpha plane becomes an /SMask, a separate stream — and a raster compositor can walk two planes as cheaply as one. Merging them here would force the PDF writer to split them apart again.

Samples are not premultiplied and carry no colour management: values are exactly what the source file encoded, in sRGB by convention.

Constructors

DecodedRasterImage(int, int, int, byte[], byte[]?)

Initializes a decoded image.

Properties

AlphaData

Gets the alpha plane, or null when the image is fully opaque.

Channels

Gets the number of colour samples per pixel.

ColorData

Gets the interleaved colour samples.

HasAlpha

Gets true when an alpha plane is present.

Height

Gets the height in pixels.

Width

Gets the width in pixels.

Methods

GetAlpha(int, int)

Reads one pixel's alpha, or 255 when the image is opaque.

GetRgb(int, int, out byte, out byte, out byte)

Reads one pixel as RGB, converting from whatever colour model the image carries.