Standard spectrum implementation for storing sampled spectral data. More...

#include <CSpectrum.h>

Inheritance diagram for icmm::CSpectrum:

Public Types
typedef imath::CSampledFunction	BaseClass

Public Types inherited from imath::CSampledFunction
typedef istd::TIndex< 1 >	Index

Public Types inherited from imath::TISampledFunction< 1, 1 >
typedef imath::TIMathFunction< istd::TIndex< ArgumentDimensions >, imath::TVector< ResultDimensions > >	BaseClass

typedef BaseClass::ArgumentType	ArgumentType

typedef BaseClass::ResultType	ResultType

typedef istd::TIndex< ArgumentDimensions >	SampleIndex

Public Types inherited from imath::TIMathFunction< istd::TIndex< ArgumentDimensions >, TVector< ResultDimensions > >
typedef istd::TIndex< ArgumentDimensions >	ArgumentType

typedef TVector< ResultDimensions >	ResultType

Public Types inherited from istd::IChangeable
enum	ChangeFlags { CF_ACF_INTERNAL = 0 , CF_ALL_DATA , CF_ANY , CF_DESTROYING , CF_DELEGATED , CF_NO_UNDO }
	Data model change notification flags. More...

enum	SupportedOperations { SO_NONE = 0 , SO_OBSERVE = 1 << 0 , SO_COPY = 1 << 1 , SO_CLONE = 1 << 2 , SO_COMPARE = 1 << 3 , SO_RESET = 1 << 4 }
	Flags for supported operations. More...

enum	CompatibilityMode { CM_STRICT , CM_WITHOUT_REFS , CM_WITH_REFS , CM_CONVERT }
	Control how relationship betweeen objects are interpreted. More...

typedef QMultiMap< QByteArray, QVariant >	ChangeInfoMap

Public Member Functions
	CSpectrum ()

	CSpectrum (const CSpectrum &other)

	CSpectrum (int startWavelength, int endWavelength, const std::vector< double > &spectrumSamples)
	Initialize with given samples First sample is at the start of the range, last sample is at the end.

	CSpectrum (const istd::CIntRange &wavelengthRange, const std::vector< double > &spectrumSamples)

	CSpectrum (int startWavelength, int endWavelength, int step)
	Zero initialize samples to fill range with given step.

	CSpectrum (const istd::CIntRange &wavelengthRange, int step)

virtual const ISpectrumInfo *	GetSpectrumInfo () const override

virtual istd::CIntRange	GetSpectralRange () const override
	Get the spectral range of the measured values given in nm.

virtual int	GetStep () const override
	Get distance/step between the samples in the spectrum definition (in nm).

virtual int	GetSamplesCount () const override
	Return number of samples.

virtual bool	Serialize (iser::IArchive &archive) override
	Load or store state of this object as a archive stream.

virtual int	GetSupportedOperations () const override
	Get set of flags for supported operations.

virtual bool	CopyFrom (const IChangeable &object, CompatibilityMode mode=CM_WITHOUT_REFS) override

virtual bool	IsEqual (const IChangeable &object) const override

virtual istd::IChangeableUniquePtr	CloneMe (CompatibilityMode mode=CM_WITHOUT_REFS) const override
	Make a copy of this object.

virtual bool	ResetData (CompatibilityMode mode=CM_WITHOUT_REFS) override
	Reset data to its default state.

Public Member Functions inherited from imath::CSampledFunction
	CSampledFunction ()

	CSampledFunction (const CSampledFunction &function)

	CSampledFunction (const imath::ISampledFunction &function)

	CSampledFunction (int size, double defaultValue=0)

bool	operator== (const CSampledFunction &other) const

void	Reset ()

bool	Initialize (int size, double defaultValue=0)

double	GetSampleValue (int index) const

void	SetSampleValue (int index, double value)

void	SetLogicalRange (const istd::CRange &logicalRange)

double	GetSamplingStep () const

double	GetSampleCoordinate (int index) const

virtual bool	CreateFunction (double *dataPtr, const ArgumentType &sizes) override
	Create function from input data.

virtual int	GetTotalSamplesCount () const override
	Get number of samples stored in this container.

virtual double	GetSampleAt (const SampleIndex &index) const override
	Get sample value at the given index.

virtual int	GetGridSize (int dimensionIndex) const override
	Get number of samples for specified dimension.

virtual istd::CRange	GetLogicalRange (int dimensionIndex) const override
	Get logical range for the specified dimension.

virtual istd::CRange	GetResultValueRange (int dimensionIndex, int resultDimension=-1) const override
	Get the range (boundary) of possible result values for the given axis.

virtual std::vector< double >	GetSamples () const override
	Get all samples as a vector.

virtual bool	GetValueAt (const ArgumentType &argument, ResultType &result) const override

virtual ResultType	GetValueAt (const ArgumentType &argument) const override

Public Member Functions inherited from imath::ISampledFunction
double	operator[] (int index) const

Public Member Functions inherited from imath::TISampledFunction< 1, 1 >
virtual int	GetArgumentDimensionality () const
	Get the number of argument components.

virtual int	GetResultDimensionality () const
	Get the number of result components.

Public Member Functions inherited from imath::TIMathFunction< istd::TIndex< ArgumentDimensions >, TVector< ResultDimensions > >
virtual bool	GetValueAt (const istd::TIndex< ArgumentDimensions > &argument, TVector< ResultDimensions > &result) const=0
	Get function value for specified argument value.

virtual TVector< ResultDimensions >	GetValueAt (const istd::TIndex< ArgumentDimensions > &argument) const=0
	Get function value for specified argument value.

Public Member Functions inherited from istd::IPolymorphic
virtual	~IPolymorphic ()

Public Member Functions inherited from istd::IChangeable
virtual bool	CopyFrom (const IChangeable &object, CompatibilityMode mode=CM_WITHOUT_REFS)
	Copy this object from another one.

virtual bool	IsEqual (const IChangeable &object) const
	Compare this object with another object.

virtual void	BeginChanges (const ChangeSet &changeSet)
	Starts the change transaction.

virtual void	EndChanges (const ChangeSet &changeSet)
	Ends the change transaction.

virtual void	BeginChangeGroup (const ChangeSet &changeSet)
	Starts group of changes.

virtual void	EndChangeGroup (const ChangeSet &changeSet)
	Ends group of changes.

Public Member Functions inherited from iser::ISerializable
virtual quint32	GetMinimalVersion (int versionId) const
	Get minimal needed version to correct storing of this data.

Additional Inherited Members
Static Public Member Functions inherited from istd::IChangeable
static const ChangeSet &	GetNoChanges ()
	Get empty set of changes.

static const ChangeSet &	GetAnyChange ()
	Get anonymous change set.

static const ChangeSet &	GetAllChanges ()
	Get anonymous change set.

static const ChangeSet &	GetDelegatedChanges ()
	Get delegated change set.

Protected Member Functions inherited from istd::IChangeable
virtual void	OnBeginChanges ()
	Callback function for begin change event.

virtual void	OnEndChanges (const ChangeSet &changeSet)
	Callback function for end change event.

Detailed Description

Standard spectrum implementation for storing sampled spectral data.

Purpose

CSpectrum provides a complete implementation for storing and manipulating spectral data - measurements of light intensity across different wavelengths. It combines sampled function capabilities with spectrum-specific information like wavelength range and step size. This is the concrete class for working with spectral color data.

Data Structure

CSpectrum stores:

Wavelength range: Min and max wavelengths (e.g., 380-780 nm for visible light)
Sample values: Intensity measurements at regular intervals
Step size: Wavelength spacing between samples
Sample count: Number of measurement points

Usage Examples

// Example 1: Creating a spectrum with explicit samples
std::vector<double> samples = {
       0.0, 0.1, 0.3, 0.5, 0.8, 1.0, 0.8, 0.5, 0.3, 0.1, 0.0
};
 
// Visible light range with custom samples
icmm::CSpectrum spectrum(380, 780, samples);
 
// Query properties
istd::CIntRange range = spectrum.GetSpectralRange();
int step = spectrum.GetStep();           // Calculated from range and samples
int count = spectrum.GetSamplesCount();  // 11
 
// Example 2: Creating a spectrum with automatic initialization
// Create spectrum covering 400-700nm with 10nm steps (31 samples)
icmm::CSpectrum spectrum(400, 700, 10);
 
// Set sample values manually
int sampleCount = spectrum.GetSamplesCount();
for (int i = 0; i < sampleCount; ++i) {
       double wavelength = 400 + i * 10;
       
       // Create peaked spectrum (e.g., laser at 550nm)
       double peak = 550.0;
       double width = 20.0;
       double intensity = exp(-pow((wavelength - peak) / width, 2.0));
       
       spectrum.SetSampleValue(i, intensity);
}
 
// Example 3: Getting interpolated values
double GetIntensityAt(const icmm::CSpectrum& spectrum, double wavelength)
{
       // Calculate() uses interpolation for wavelengths between samples
       double intensity;
       if (spectrum.Calculate(wavelength, intensity)) {
              return intensity;
       }
       return 0.0;
}
 
// Get intensity at 525nm (interpolated)
double intensity525 = GetIntensityAt(spectrum, 525.0);
 
// Example 4: Creating standard illuminants
icmm::CSpectrum CreateD65Illuminant()
{
       // D65 daylight illuminant (simplified)
       std::vector<double> d65Samples = {
              50.0, 52.3, 54.6, 68.7, 82.8, 87.1, 91.5, 92.5,
              93.4, 90.1, 86.7, 95.8, 104.9, 110.9, 117.0
              // ... more samples across visible range
       };
       
       return icmm::CSpectrum(380, 780, d65Samples);
}
 
// Example 5: Analyzing spectrum properties
struct SpectrumStats {
       double peakWavelength;
       double peakIntensity;
       double totalEnergy;
};
 
SpectrumStats AnalyzeSpectrum(const icmm::CSpectrum& spectrum)
{
       SpectrumStats stats;
       stats.peakIntensity = 0.0;
       stats.totalEnergy = 0.0;
       
       istd::CIntRange range = spectrum.GetSpectralRange();
       int step = spectrum.GetStep();
       int count = spectrum.GetSamplesCount();
       
       for (int i = 0; i < count; ++i) {
              double intensity = spectrum.GetSampleValue(i);
              double wavelength = range.GetMin() + i * step;
              
              // Find peak
              if (intensity > stats.peakIntensity) {
                     stats.peakIntensity = intensity;
                     stats.peakWavelength = wavelength;
              }
              
              // Integrate energy
              stats.totalEnergy += intensity * step;
       }
       
       return stats;
}
 
// Example 6: Saving and loading spectra
void SaveSpectrum(const icmm::CSpectrum& spectrum, const QString& filename)
{
       ifile::CFileWriteArchive archive(filename);
       if (archive.IsOpen()) {
              icmm::CSpectrum copy = spectrum;
              copy.Serialize(archive);
       }
}
 
void LoadSpectrum(icmm::CSpectrum& spectrum, const QString& filename)
{
       ifile::CFileReadArchive archive(filename);
       if (archive.IsOpen()) {
              spectrum.Serialize(archive);
       }
}
 
// Example 7: Normalizing spectrum
void NormalizeSpectrum(icmm::CSpectrum& spectrum)
{
       // Find maximum intensity
       double maxIntensity = 0.0;
       int count = spectrum.GetSamplesCount();
       
       for (int i = 0; i < count; ++i) {
              double intensity = spectrum.GetSampleValue(i);
              if (intensity > maxIntensity) {
                     maxIntensity = intensity;
              }
       }
       
       // Normalize to [0, 1]
       if (maxIntensity > 0.0) {
              for (int i = 0; i < count; ++i) {
                     double intensity = spectrum.GetSampleValue(i);
                     spectrum.SetSampleValue(i, intensity / maxIntensity);
              }
       }
}
 
// Example 8: Combining spectra (e.g., light filtering)
icmm::CSpectrum MultiplySpectra(const icmm::CSpectrum& spectrum1,
                               const icmm::CSpectrum& spectrum2)
{
       // Assumes same wavelength range and sampling
       icmm::CSpectrum result = spectrum1;
       
       int count = result.GetSamplesCount();
       for (int i = 0; i < count; ++i) {
              double value1 = spectrum1.GetSampleValue(i);
              double value2 = spectrum2.GetSampleValue(i);
              result.SetSampleValue(i, value1 * value2);
       }
       
       return result;
}

Applications

Color science: Converting spectra to tristimulus values (XYZ)
Lighting: Characterizing light sources (LEDs, sunlight, etc.)
Materials: Measuring reflectance, transmittance, emission spectra
Spectroscopy: Analyzing chemical composition
Rendering: Physics-based light transport
Photography: Camera spectral sensitivity

Common Wavelength Ranges

Visible light: 380-780 nm
Extended visible: 360-830 nm
UV-Visible-IR: 300-1000 nm
Typical step: 1, 5, or 10 nm

Best Practices

Use consistent wavelength ranges within a project
Choose step size based on required accuracy (smaller = more accurate, larger = more efficient)
Normalize spectra for comparison
Use interpolation (Calculate method) for wavelengths between samples
Store spectra in appropriate units (absolute or relative)
Consider using standard illuminants (D65, A, F2) for consistency

See also: icmm::ISpectrum, icmm::ISpectrumInfo, imath::CSampledFunction, icmm::CSpectralColor, icmm::ISpectrumInfoProvider

Definition at line 211 of file CSpectrum.h.

Member Typedef Documentation

◆ BaseClass

typedef imath::CSampledFunction icmm::CSpectrum::BaseClass

Definition at line 218 of file CSpectrum.h.

Constructor & Destructor Documentation

◆ CSpectrum() [1/6]

icmm::CSpectrum::CSpectrum ( )

◆ CSpectrum() [2/6]

icmm::CSpectrum::CSpectrum ( const CSpectrum & other )

◆ CSpectrum() [3/6]

icmm::CSpectrum::CSpectrum	(	int	startWavelength,
		int	endWavelength,
		const std::vector< double > &	spectrumSamples
	)

Initialize with given samples First sample is at the start of the range, last sample is at the end.

◆ CSpectrum() [4/6]

icmm::CSpectrum::CSpectrum	(	const istd::CIntRange &	wavelengthRange,
		const std::vector< double > &	spectrumSamples
	)

◆ CSpectrum() [5/6]

icmm::CSpectrum::CSpectrum	(	int	startWavelength,
		int	endWavelength,
		int	step
	)

Zero initialize samples to fill range with given step.

◆ CSpectrum() [6/6]

icmm::CSpectrum::CSpectrum	(	const istd::CIntRange &	wavelengthRange,
		int	step
	)

Member Function Documentation

◆ CloneMe()

virtual istd::IChangeableUniquePtr icmm::CSpectrum::CloneMe ( CompatibilityMode mode = CM_WITHOUT_REFS ) const

overridevirtual

Make a copy of this object.

Returns: new instance or NULL, if this operation is not supported.

Reimplemented from imath::CSampledFunction.

◆ CopyFrom()

virtual bool icmm::CSpectrum::CopyFrom	(	const IChangeable &	object,
		CompatibilityMode	mode = `CM_WITHOUT_REFS`
	)

overridevirtual

Reimplemented from imath::CSampledFunction.

◆ GetSamplesCount()

virtual int icmm::CSpectrum::GetSamplesCount ( ) const

overridevirtual

Return number of samples.

Implements icmm::ISpectrumInfo.

◆ GetSpectralRange()

virtual istd::CIntRange icmm::CSpectrum::GetSpectralRange ( ) const

overridevirtual

Get the spectral range of the measured values given in nm.

Implements icmm::ISpectrumInfo.

◆ GetSpectrumInfo()

virtual const ISpectrumInfo * icmm::CSpectrum::GetSpectrumInfo ( ) const

overridevirtual

Implements icmm::ISpectrumInfoProvider.

◆ GetStep()

virtual int icmm::CSpectrum::GetStep ( ) const

overridevirtual

Get distance/step between the samples in the spectrum definition (in nm).

We assume that we have regular sampling grid.

Implements icmm::ISpectrumInfo.

◆ GetSupportedOperations()

virtual int icmm::CSpectrum::GetSupportedOperations ( ) const

overridevirtual

Get set of flags for supported operations.

See also: SupportedOperations

Reimplemented from imath::CSampledFunction.

◆ IsEqual()

virtual bool icmm::CSpectrum::IsEqual ( const IChangeable & object ) const

overridevirtual

Reimplemented from imath::CSampledFunction.

◆ ResetData()

virtual bool icmm::CSpectrum::ResetData ( CompatibilityMode mode = CM_WITHOUT_REFS )

overridevirtual

Reset data to its default state.

Default implementation in istd::IChangeable does nothing.

Returns: true if the operation was successful, and false otherwise.

Reimplemented from imath::CSampledFunction.

◆ Serialize()

virtual bool icmm::CSpectrum::Serialize ( iser::IArchive & archive )

overridevirtual

Load or store state of this object as a archive stream.

Type of operation is depending on archive type.

See also: iser::IArchive

Implements iser::ISerializable.

The documentation for this class was generated from the following file:

Acf/Include/icmm/CSpectrum.h

Public Types

Public Member Functions

Additional Inherited Members

Detailed Description

Purpose

Data Structure

Usage Examples

Applications

Common Wavelength Ranges

Best Practices

Member Typedef Documentation

◆ BaseClass

Constructor & Destructor Documentation

◆ CSpectrum() [1/6]

◆ CSpectrum() [2/6]

◆ CSpectrum() [3/6]

◆ CSpectrum() [4/6]

◆ CSpectrum() [5/6]

◆ CSpectrum() [6/6]

Member Function Documentation

◆ CloneMe()

◆ CopyFrom()

◆ GetSamplesCount()

◆ GetSpectralRange()

◆ GetSpectrumInfo()

◆ GetStep()

◆ GetSupportedOperations()

◆ IsEqual()

◆ ResetData()

◆ Serialize()