Class: TYIQColor

Declaration: YIQColor.h

Taxonomy Categories:

Member Functions:


Interface Category:

API.

Inherits From:

TColor

Inherited By:

None.

Purpose:

The National Television System Committee (NTSC) in 1952 defined the color television system which is used in North America and Japan. In doing so, they also defined the CIE xy chromaticity coordinates of the display phosphors as: Phosphors x y z Red 0.67 0.33 0.00 Green 0.21 0.71 0.08 Blue 0.14 0.08 0.78 The Y is defined as luminance and is exactly the same as the Y in the XYZ color space. It is also the same as the black and white signals on a TV. Two chromaticities, represented by I and Q, are used to transmit color information. The class provides arithmetic operators that operate on two colors.

Instantiation:

Allocate on the heap or the stack.

Deriving Classes:

Derive new color models from TColor.

Concurrency:

Multithread safe.

Resource Use:

No special requirements.

Member Function: TYIQColor::TYIQColor

  1. TYIQColor ()
  2. TYIQColor (const TColor & aColor)
  3. TYIQColor (TColorProfile * theDeviceColorProfile)
  4. TYIQColor (GIntensity aY, GIntensity aI, GIntensity aQ, GIntensity opacity =1.0)
  5. TYIQColor (const TYIQColor & aYIQColor)
  6. TYIQColor (TColorProfile * theDeviceColorProfile, GIntensity aY, GIntensity aI, GIntensity aQ, GIntensity opacity =1.0)

Interface Category:

API.

Purpose:

  1. Default constructor; it has the default color profile, and color components are not initialized.
  2. Creates a TYIQColor from a TColor.
  3. Creates a TYIQColor with the specified color profile. The color components are not initialized.
  4. Creates a TYIQColor with the specified components. It has the default color profile.
  5. Copy constructor.
  6. Creates a TYIQColor with the specified components and color profile.

Calling Context:

  1. Called by the stream-in operators. You can also call this function directly.
  2. Call this function directly.
  3. Call this function directly.
  4. Call this function directly.
  5. Called to copy an object. You can also call this function directly.
  6. Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Member Function: TYIQColor::GetComponents

void GetComponents (GIntensity & aY, GIntensity & aI, GIntensity & aQ, GIntensity & opacity) const

Interface Category:

API.

Purpose:

Gets the components of this TCMYKColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::GetClampedComponents

void GetClampedComponents (GIntensity & aY, GIntensity & aI, GIntensity & aQ, GIntensity & opacity) const

Interface Category:

API.

Purpose:

Gets the components of this TYIQColor clamped between 0.0 <= N <=1.0.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::GetY

GIntensity GetY () const

Interface Category:

API.

Purpose:

Gets the Y component of this TYIQColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns the Y component of the color.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::GetI

GIntensity GetI () const

Interface Category:

API.

Purpose:

Gets the I component of this TYIQColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns the I component of the color.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::GetQ

GIntensity GetQ () const

Interface Category:

API.

Purpose:

Gets the Q component of this TYIQColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns the Q component of the color.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::GetColorDifference

GCoordinate GetColorDifference (const TYIQColor & aColor2) const

Interface Category:

API.

Purpose:

Calculates the color difference between this TYIQColor and the specified one. The color difference is defined as the sqrt( (Y1-Y2)^2+(I1-I2)^2+(Q1-Q2)^2 ).

Calling Context:

Call this function directly.

Parameters:

Return Value:

The value of the color difference between the two colors.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::SetComponents

void SetComponents (GIntensity aY, GIntensity aI, GIntensity aQ, GIntensity opacity =1.0)

Interface Category:

API.

Purpose:

Sets the components of this TYIQColor to the specified values.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::SetI

void SetI (GIntensity aI)

Interface Category:

API.

Purpose:

Sets the I component of this TYIQColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::SetQ

void SetQ (GIntensity aQ)

Interface Category:

API.

Purpose:

Sets the Q component of this TYIQColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::operatorTRGBColor

virtual operator TRGBColor () const

Interface Category:

API.

Purpose:

Casts this TYIQColor to a TRGBColor.

Calling Context:

Call this operator directly.

Parameters:

Return Value:

Returns an RGBColor that corresponds to this color.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::operatorTXYZColor

virtual operator TXYZColor () const

Interface Category:

API.

Purpose:

Casts this TYIQColor to a TXYZColor.

Calling Context:

Call this operator directly.

Parameters:

Return Value:

Returns an XYZColor that corresponds to this color.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::operator=

  1. TYIQColor & operator =(const TYIQColor & aSource)
  2. TColor & operator =(const TColor & aSource)

Interface Category:

API.

Purpose:

  1. Assignment operator.
  2. Assignment operator that casts the specified operand to a TYIQColor.

Calling Context:

  1. Called when an object is assigned to another compatible object.
  2. Called when an object is assigned to another compatible object.

Parameters:

Return Value:

A non-const reference to the left-hand side object.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::operator+

  1. TYIQColor operator + (const TYIQColor & aColor2) const
  2. TYIQColor operator + (const float aScalar) const

Interface Category:

API.

Purpose:

  1. Adds the components of the two TYIQColors together.
  2. Adds the specified scalar to each component of this TYIQColor.

Calling Context:

  1. Call this operator directly.
  2. Call this operator directly.

Parameters:

Return Value:

  1. Returns a new color with the new components.
  2. Returns a new color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The values of the components are not clamped to the range 0.0 <= N <= 1.0.

Member Function: TYIQColor::operator-

  1. TYIQColor operator -(const TYIQColor & aColor2) const
  2. TYIQColor operator -(const float aScalar) const

Interface Category:

API.

Purpose:

  1. Subtracts the components of the specified color from this TYIQColor.
  2. Subtracts the specified scalar from each component of this TYIQColor.

Calling Context:

  1. Call this operator directly.
  2. Call this operator directly.

Parameters:

Return Value:

  1. Returns a new color with the new components.
  2. Returns a new color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The values of the components are not clamped to the range 0.0 <= N <= 1.0.

Member Function: TYIQColor::operator*

  1. TYIQColor operator * (const float aScalar) const
  2. TYIQColor operator * (const TYIQColor & aColor2) const

Interface Category:

API.

Purpose:

  1. Multiplies each component of this TYIQColor by the specified scalar.
  2. Multiplies the components of this TYIQColor by the components of the specified color.

Calling Context:

  1. Call this operator directly.
  2. Call this operator directly.

Parameters:

Return Value:

  1. Returns a new color with the new components.
  2. Returns a new color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The values of the components are not clamped to the range 0.0 <= N <= 1.0.

Member Function: TYIQColor::operator/=

TYIQColor & operator /= (const float aScalar)

Interface Category:

API.

Purpose:

Divides the components of this TYIQColor by the specified scalar and assigns the new values to the respective components.

Calling Context:

Call this operator directly.

Parameters:

Return Value:

Returns this color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TYIQColor::operator+=

  1. TYIQColor & operator += (const float aScalar)
  2. TYIQColor & operator += (const TYIQColor & aColor2)

Interface Category:

API.

Purpose:

  1. Adds the specified scalar to the components of this TYIQColor and assigns the new values to the respective components.
  2. Adds the specified colors to the components of this TYIQColor and assigns the new values to the respective components.

Calling Context:

  1. Call this operator directly.
  2. Call this operator directly.

Parameters:

Return Value:

Returns this color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TYIQColor::operator-=

  1. TYIQColor & operator -=(const float aScalar)
  2. TYIQColor & operator -=(const TYIQColor & aColor2)

Interface Category:

API.

Purpose:

  1. Subtracts the specified scalar from the components of this TYIQColor and assigns the new values to the respective components.
  2. Subtracts the specified scalar from the components of this TYIQColor and assigns the new values to the respective components.

Calling Context:

  1. Call this operator directly.
  2. Call this operator directly.

Parameters:

Return Value:

Returns this color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TYIQColor::operator*=

TYIQColor & operator *= (const float aScalar)

Interface Category:

API.

Purpose:

Multiplies the components of this TYIQColor by the specified scalar and assigns the new values to the respective components.

Calling Context:

Call this operator directly.

Parameters:

Return Value:

Returns this color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TYIQColor::operator/

TYIQColor operator / (const float aScalar) const

Interface Category:

API.

Purpose:

Divides each component of this TYIQColor by the specified scalar.

Calling Context:

Call this operator directly.

Parameters:

Return Value:

Returns this color with the new components.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The values of the components are not clamped to the range 0.0 <= N <= 1.0.

Member Function: TYIQColor::FuzzyCompare

  1. bool FuzzyCompare (const TYIQColor & aYIQColor, float acceptableErrorPerComponent =0.0001) const
  2. bool FuzzyCompare (const TYIQColor & aYuvColor, float errOpacity, float errY, float errI, float errQ) const

Interface Category:

API.

Purpose:

  1. Compares this TYIQColor and the specified color with reference to the specified tolerance. It takes the absolute difference between the components of the color and compares them to a known value.
  2. Compares this TYIQColor and the specified color to a given accuracy on a component by component level.

Calling Context:

  1. Call this function directly.
  2. Call this function directly.

Parameters:

Return Value:

  1. Returns true if the two colors are equal with reference to the specified tolerance.
  2. Returns true if the two colors are equal with reference to the specified tolerance.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::LinearInterpolate

void LinearInterpolate (const float aWeight, const TYIQColor & aColor2)

Interface Category:

API.

Purpose:

Makes a weighted linear interpolation of each component of this TYIQColor. The interpolation is returned in this color. The interpolation that is done for each component is (using Y as an example) given by Y1 =Y1 + (Y2 -Y1) * Weight.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TYIQColor::AddAndPin

void AddAndPin (const TYIQColor & aColor2)

Interface Category:

API.

Purpose:

Adds the specified color to this TYIQColor and then clamps the resulting values of the components.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TYIQColor::SubtractAndPin

void SubtractAndPin (const TYIQColor & aColor2)

Interface Category:

API.

Purpose:

Subtracts the specified color from this TYIQColor and then clamps the resulting values of the components.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TYIQColor::Maximum

void Maximum (const TYIQColor & aColor2)

Interface Category:

API.

Purpose:

Determines the maximum of individual components of this TYIQColor and the specified color. It sets the components of this color to the resulting maximum values.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TYIQColor::Minimum

void Minimum (const TYIQColor & aColor2)

Interface Category:

API.

Purpose:

Determines the minimum of individual components of this TYIQColor and the specified color. It sets the components of this color to the resulting minimum values.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TYIQColor::Blend

void Blend (const TYIQColor & aColor2)

Interface Category:

API.

Purpose:

Averages the individual components of the two colors and returns them in this TYIQColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TYIQColor::Invert

void Invert ()

Interface Category:

API.

Purpose:

Inverts this TYIQColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TYIQColor::Clamp

void Clamp ()

Interface Category:

API.

Purpose:

Clamps the components of this TYIQColor between 0.0 <= N <= 1.0. If a value is less than 0.0, it is set to 0.0, and if it is greater than 1.0, it is set to 1.0.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TYIQColor::Scale

void Scale ()

Interface Category:

API.

Purpose:

Scales this TYIQColor to 1.0. If all of the color's components are between 0.0 <= N <= 1.0, the color is untouched. If there are components with values greater than 1.0, then the largest component is used to renormalize the color. If any of the color's components are less than 0.0 they are set to 0.0.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

The color's opacity is set to 1.0.

Member Function: TYIQColor::TemporaryTypeID

virtual TemporaryColorClassID TemporaryTypeID () const

Interface Category:

API.

Purpose:

Returns TColor::kYIQColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns TColor::kYIQColor.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::operator<<=

virtual TStream & operator <<= (TStream &)

Interface Category:

API.

Purpose:

Stream-in operator.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns a reference to the stream the object streams itself in from.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::operator>>=

virtual TStream & operator >>=(TStream &) const

Interface Category:

API.

Purpose:

Stream-out operator.

Calling Context:

Called to stream out data.

Parameters:

Return Value:

Returns a reference to the stream the object streams itself out to.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::SetY

void SetY (GIntensity aY)

Interface Category:

API.

Purpose:

Sets the Y component of this TYIQColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::~TYIQColor

virtual ~ TYIQColor ()

Interface Category:

API.

Purpose:

Destructor.

Calling Context:

Called to destroy an object.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::ClampOpacity

void ClampOpacity ()

Interface Category:

API.

Purpose:

Pins the opacity of this TYIQColor to the range 0.0 to 1.0.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::SetOpacity

void SetOpacity (GIntensity opacity =1.0)

Interface Category:

API.

Purpose:

Sets the opacity of this TYIQColor to the specified value.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::GetClampedOpacity

GIntensity GetClampedOpacity () const

Interface Category:

API.

Purpose:

Returns the opacity of this TYIQColor and pins the value to the range 0.0 to 1.0.

Calling Context:

Call this function directly.

Parameters:

Return Value:

The clamped opacity.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.

Member Function: TYIQColor::GetOpacity

GIntensity GetOpacity () const

Interface Category:

API.

Purpose:

Returns the opacity of this TYIQColor.

Calling Context:

Call this function directly.

Parameters:

Return Value:

The opacity that can be outside the range 0.0 to 1.0.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Multithread safe.

Other Considerations:

None.
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