deconvolve(_:reference:kernel:)

Converts a pixel array to an image data buffer, using the given pixel kernel and referencing function.

static func deconvolve<A, T, C>(_ pixels: [C], reference: ((A, A, A)) -> Int, kernel: (C) -> (T, T, T)) -> [UInt8] where A : FixedWidthInteger, A : UnsignedInteger, T : FixedWidthInteger, T : UnsignedInteger

Mangled symbol

s3PNGAAO10deconvolve_9reference6kernelSays5UInt8VGSayq0_G_Six_xxt_tXEq__q_q_tq0_XEts17FixedWidthIntegerRzSURzsAJR_SUR_r1_lFZWhat are these?

FNV24: [6N3S1]

Parameters

pixels: A pixel array.
reference: A referencing function. Its return value must be in the range 0 ... 255. Depending on bit depth of the image it is being used for, there may be further restrictions on the range of the returned indices.
kernel: A pixel kernel.

Returns

An image data buffer. This array has the same number of elements as pixels.

This function maps the given kernel function over each element in pixels, receiving (T, T, T) intensity triplets in return. It then converts them into atoms of type A, scaling each intensity value to the range of A. Each (A, A, A) triplet is then converted to an Int index using the given reference function, and stored as a byte in the returned image data buffer.

A worked example of how to use this function to implement a custom color target can be found in the custom color targets tutorial.

Other members in extension

Protocols

protocol BytestreamDestination
A destination bytestream.
protocol BytestreamSource
A source bytestream.
protocol Color<Aggregate>
A color target.
protocol Error
Functionality common to all library error types.

Types

struct Background
A background descriptor.
struct Chromaticity
A chromaticity descriptor.
struct Chunk
A chunk type identifier.
struct ColorProfile
An embedded color profile.
enum ColorRendering
A color rendering mode.
struct Context
A decoding context.
enum DecodingError
A decoding error.
enum Format
A color format.
enum FormattingError
A formatting error.
struct Gamma
A gamma descriptor.
struct Header
An image header.
struct Histogram
A palette frequency histogram.
struct Image
A rectangular image.
struct Layout
An image layout.
enum LexingError
A lexing error.
struct Metadata
The metadata in a PNG image.
struct Palette
An image palette.
enum ParsingError
A parsing error.
struct Percentmille
A rational percentmille value.
struct PhysicalDimensions
A physical dimensions descriptor.
struct RGBA<T>
An RGBA color target.
struct SignificantBits
A color precision descriptor.
enum Standard
A PNG standard.
struct SuggestedPalette
A suggested image palette.
struct Text
A text comment.
struct TimeModified
An image modification time.
struct Transparency
A transparency descriptor.
struct VA<T>
A grayscale-alpha color target.

Show obsolete interfaces (2)

enum Bytestream
A namespace for bytestream utilities.
enum Data
A namespace containing the Image type.

Type members

static func convolve<A, T, C>([UInt8], dereference: (Int) -> A, kernel: (T) -> C) -> [C]
Converts an image data buffer to a pixel array, using the given pixel kernel and dereferencing function.
static func convolve<A, T, C>([UInt8], dereference: (Int) -> (A, A), kernel: ((T, T)) -> C) -> [C]
Converts an image data buffer to a pixel array, using the given pixel kernel and dereferencing function.
static func convolve<A, T, C>([UInt8], dereference: (Int) -> (A, A, A), kernel: ((T, T, T)) -> C) -> [C]
Converts an image data buffer to a pixel array, using the given pixel kernel and dereferencing function.
static func convolve<A, T, C>([UInt8], dereference: (Int) -> (A, A, A, A), kernel: ((T, T, T, T)) -> C) -> [C]
Converts an image data buffer to a pixel array, using the given pixel kernel and dereferencing function.
static func convolve<A, T, C>([UInt8], of: A.Type, depth: Int, kernel: ((T, T, T, T)) -> C) -> [C]
Converts an image data buffer to a pixel array, using the given pixel kernel.
static func convolve<A, T, C>([UInt8], of: A.Type, depth: Int, kernel: ((T, T, T), (A, A, A)) -> C) -> [C]
Converts an image data buffer to a pixel array, using the given pixel kernel.
static func convolve<A, T, C>([UInt8], of: A.Type, depth: Int, kernel: ((T, T)) -> C) -> [C]
Converts an image data buffer to a pixel array, using the given pixel kernel.
static func convolve<A, T, C>([UInt8], of: A.Type, depth: Int, kernel: (T, A) -> C) -> [C]
Converts an image data buffer to a pixel array, using the given pixel kernel.
static func deconvolve<A, T, C>([C], as: A.Type, depth: Int, kernel: (C) -> (T, T, T, T)) -> [UInt8]
Converts a pixel array to an image data buffer, using the given pixel kernel.
static func deconvolve<A, T, C>([C], as: A.Type, depth: Int, kernel: (C) -> (T, T, T)) -> [UInt8]
Converts a pixel array to an image data buffer, using the given pixel kernel.
static func deconvolve<A, T, C>([C], as: A.Type, depth: Int, kernel: (C) -> (T, T)) -> [UInt8]
Converts a pixel array to an image data buffer, using the given pixel kernel.
static func deconvolve<A, T, C>([C], as: A.Type, depth: Int, kernel: (C) -> T) -> [UInt8]
Converts a pixel array to an image data buffer, using the given pixel kernel.
static func deconvolve<A, T, C>([C], reference: (A) -> Int, kernel: (C) -> T) -> [UInt8]
Converts a pixel array to an image data buffer, using the given pixel kernel and referencing function.
static func deconvolve<A, T, C>([C], reference: ((A, A)) -> Int, kernel: (C) -> (T, T)) -> [UInt8]
Converts a pixel array to an image data buffer, using the given pixel kernel and referencing function.
static func deconvolve<A, T, C>([C], reference: ((A, A, A, A)) -> Int, kernel: (C) -> (T, T, T, T)) -> [UInt8]
Converts a pixel array to an image data buffer, using the given pixel kernel and referencing function.
static func premultiply<T>(T, alpha: T) -> T
Premultiplies a color component with an alpha value.
static func straighten<T>(T, alpha: T) -> T
Straightens a premultiplied color component given an alpha value.