qualpal Namespace Reference

Qualitative color palette generation library. More...

Namespaces
namespace	colors
	Color representation classes for various color spaces.
namespace	metrics
	Color difference metrics for perceptual color comparison.

Classes
class	FixedMatrix
	Fixed-size matrix class with compile-time dimensions. More...
class	Matrix
	Dynamic matrix class with runtime-determined dimensions. More...
struct	PaletteAnalysis
	Holds analysis results for a color palette under a specific vision condition. More...
class	Qualpal
	Builder for qualitative color palette generation. More...
class	Threads
	Centralized management of thread settings for parallel computations. More...

Typedefs
using	PaletteAnalysisMap = std::map< std::string, PaletteAnalysis >
	Map from vision deficiency type to palette analysis results.

Enumerations
enum class	ColorspaceType { HSL , LCHab }
	Supported cylindrical color spaces for input colors. More...

Functions
PaletteAnalysisMap	analyzePalette (const std::vector< colors::RGB > &colors, const metrics::MetricType &metric=metrics::MetricType::CIEDE2000, const std::map< std::string, double > &cvd={ { "deutan", 1.0 }, { "protan", 1.0 }, { "tritan", 1.0 } }, const std::optional< colors::RGB > &bg=std::nullopt, double max_memory=1.0)
	Analyze a color palette for normal and simulated color vision deficiencies (CVD).
template<typename ColorType , typename Metric = metrics::DIN99d>
Matrix< double >	colorDifferenceMatrix (const std::vector< ColorType > &colors, const Metric &metric=Metric{}, const double max_memory=1)
	Generate a symmetric color difference matrix for a set of colors.
Matrix< double >	colorDifferenceMatrix (const std::vector< colors::XYZ > &colors, const metrics::MetricType &metric_type, const double max_memory=1)
	Generate a color difference matrix for XYZ colors with runtime metric selection.

Detailed Description

Qualitative color palette generation library.

Typedef Documentation

PaletteAnalysisMap

using qualpal::PaletteAnalysisMap = typedef std::map<std::string, PaletteAnalysis>

Map from vision deficiency type to palette analysis results.

The key is a string representing the vision type:

• "normal" : Normal color vision (no simulation)
• "deutan" : Deuteranomaly simulation
• "protan" : Protanomaly simulation
• "tritan" : Tritanomaly simulation

The value is a PaletteAnalysis struct with results for that vision type.

Definition at line 59 of file analyze.h.

Enumeration Type Documentation

ColorspaceType

enum class qualpal::ColorspaceType

strong

Supported cylindrical color spaces for input colors.

This enum defines the available cylindrical color spaces that can be used for generating palettes. Currently, it supports HSL (Hue, Saturation, Lightness) and LCHab (Lightness, Chroma, Hue in CIE Lab).

Definition at line 63 of file qualpal.h.

Function Documentation

analyzePalette()

PaletteAnalysisMap qualpal::analyzePalette	(	const std::vector< colors::RGB > &	colors,
		const metrics::MetricType &	metric = metrics::MetricType::CIEDE2000,
		const std::map< std::string, double > &	cvd = { { "deutan", 1.0 }, { "protan", 1.0 }, { "tritan", 1.0 } },
		const std::optional< colors::RGB > &	bg = std::nullopt,
		double	max_memory = 1.0
	)

Analyze a color palette for normal and simulated color vision deficiencies (CVD).

Computes color difference matrices and minimum color distances for the input palette, for normal vision as well as common color vision deficiencies ("deutan", "protan", "tritan") at the specified severity. Results are returned as a map keyed by vision type.

For each vision type:

• Simulates the palette (and optional background) under the specified CVD severity.
• Computes the pairwise color difference matrix using the selected metric.
• Computes the minimum distance to any other color for each palette color.
• Computes the minimum distance from the background (if provided) to the palette.

Parameters

colors	Vector of RGB colors to analyze. Each channel should be in [0, 1].
metric	Color difference metric to use (e.g., CIEDE2000, DIN99d, CIE76).
cvd	Map of CVD type ("deutan", "protan", "tritan") to severity [0, 1]. If a type is omitted or severity is 0, simulation is skipped for that type.
bg	Optional background color to include in the analysis (RGB in [0, 1]).
max_memory	Maximum memory (in GB) allowed for the difference matrix computation.

Returns

Map from vision type string to PaletteAnalysis for each simulated vision.

Exceptions

std::invalid_argument

if input parameters are invalid.

See also

PaletteAnalysis, PaletteAnalysisMap

colorDifferenceMatrix() [1/2]

Matrix< double > qualpal::colorDifferenceMatrix	(	const std::vector< colors::XYZ > &	colors,
		const metrics::MetricType &	metric_type,
		const double	max_memory = 1
	)

Generate a color difference matrix for XYZ colors with runtime metric selection.

Computes the pairwise color differences between all colors in the input vector, using the specified color difference metric (selected at runtime via MetricType). Internally converts XYZ colors to the appropriate color space for the selected metric.

Parameters

colors	Vector of colors::XYZ colors to compare.
metric_type	Color difference metric to use (DIN99d, CIEDE2000, or CIE76).
max_memory	Maximum memory (in GB) allowed for the matrix (default: 1.0).

Returns

Matrix<double> Symmetric matrix of pairwise color differences [size: n x n].

Exceptions

std::invalid_argument	if the metric type is unsupported or input is invalid.
std::runtime_error	if the estimated matrix size exceeds max_memory.

See also

metrics::MetricType

colorDifferenceMatrix() [2/2]

template<typename ColorType , typename Metric = metrics::DIN99d>

Matrix< double > qualpal::colorDifferenceMatrix	(	const std::vector< ColorType > &	colors,
		const Metric &	metric = Metric{},
		const double	max_memory = 1
	)

Generate a symmetric color difference matrix for a set of colors.

Computes the pairwise perceptual color differences between all colors in the input vector, using the specified color difference metric (e.g., DIN99d, CIEDE2000, CIE76). The result is a symmetric matrix where element (i, j) is the distance between colors[i] and colors[j].

Template Parameters

ColorType	Any color class convertible to the required color space (e.g., colors::RGB, colors::HSL, colors::XYZ, colors::Lab, colors::DIN99d).
Metric	Color difference metric functor (defaults to metrics::DIN99d).

Parameters

colors	Vector of colors to compare.
metric	Color difference metric to use (optional; default is DIN99d).
max_memory	Maximum memory (in GB) allowed for the matrix (default: 1.0).

Returns

Matrix<double> Symmetric matrix of pairwise color differences [size: n x n].

Exceptions

std::invalid_argument	if fewer than one color is provided.
std::runtime_error	if the estimated matrix size exceeds max_memory.

See also

metrics::DIN99d, metrics::CIEDE2000, metrics::CIE76

Definition at line 65 of file color_difference.h.