convolve(_:of:depth:kernel:)

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

static func convolve<A, T, C>(_ buffer: [UInt8], of _: A.Type, depth: Int, kernel: ((T, T, T, T)) -> C) -> [C] where A : FixedWidthInteger, A : UnsignedInteger, T : FixedWidthInteger, T : UnsignedInteger

Mangled symbol

s3PNGAAO8convolve_2of5depth6kernelSayq0_GSays5UInt8VG_xmSiq0_q__q_q_q_t_tXEts17FixedWidthIntegerRzSURzsAKR_SUR_r1_lFZWhat are these?

FNV24: [1TEDY]

Parameters

buffer: An image data buffer. Its length must be divisible by four times the stride of A.
_: An atom type.
depth: A color depth used to interpret the intensity of each atom. This depth must be no greater than A.bitWidth.
kernel: A pixel kernel.

Returns

An array of pixels constructed by the given kernel function. This array has a length of buffer.count divided by the four times the stride of A.

This function interprets buffer as an array of big-endian atoms of type A. It then scales the atoms to the range of T, according to the given color depth, and constructs instances of C by mapping the given kernel function over consecutive (T, T, T, T) quadruplets.

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), (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)) -> Int, kernel: (C) -> (T, 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.