ossim2dBilinearTransform Class Reference

ossim2dBilinearTransform allows one to specify a set of input points and output points and will fit a bilinear transform to those points. More...

#include <ossim2dBilinearTransform.h>

Inheritance diagram for ossim2dBilinearTransform:

Public Member Functions
	ossim2dBilinearTransform ()
	Initialize to the identity. More...
	ossim2dBilinearTransform (const ossimDpt *input, const ossimDpt *output, ossim_uint32 arraySize)
	Initialize the transform that best fits the input and output arrays. More...
	ossim2dBilinearTransform (const ossimDpt &in1, const ossimDpt &in2, const ossimDpt &in3, const ossimDpt &in4, const ossimDpt &out1, const ossimDpt &out2, const ossimDpt &out3, const ossimDpt &out4)
	Mapping 4 corners to an output 4 corners. More...
	ossim2dBilinearTransform (const ossim2dBilinearTransform &src)
	Copy constructor. More...
virtual ossimObject *	dup () const
	Duplication method that duplicates this object. More...
const ossim2dBilinearTransform &	operator= (const ossim2dBilinearTransform &src)
	Overloaded operator equal that allows for assignment. More...
void	setFromPoints (const ossimDpt &in1, const ossimDpt &in2, const ossimDpt &in3, const ossimDpt &in4, const ossimDpt &out1, const ossimDpt &out2, const ossimDpt &out3, const ossimDpt &out4)
	Mapping 4 corners to an output 4 corners. More...
void	setFromPoints (const ossimDpt *input, const ossimDpt *output, ossim_uint32 arraySize)
	Initialize the transform that best fits the input and output arrays. More...
virtual void	forward (const ossimDpt &input, ossimDpt &output) const
	forward transform will transform an input point to the output. More...
virtual void	forward (ossimDpt &modify_this) const
	forward transform will transform an input point to the output and modify the passed in point to the new value More...
virtual void	inverse (const ossimDpt &input, ossimDpt &output) const
	Inverts the point back to the original input value. More...
virtual void	inverse (ossimDpt &modify_this) const
	Inverts the point back to the original input value and modifies the passed in point to the new value. More...
virtual bool	saveState (ossimKeywordlist &kwl, const char *prefix=0) const
	Saves the state of this object. More...
virtual bool	loadState (const ossimKeywordlist &kwl, const char *prefix=0)
	loads the state of this object from a keywordlist. More...
virtual std::ostream &	print (std::ostream &out) const
	prints the contents of this object. More...
Public Member Functions inherited from ossim2dTo2dTransform
virtual const ossim2dTo2dTransform &	operator= (const ossim2dTo2dTransform &rhs)
virtual ossimDpt	getOrigin () const
void	setConvergenceThreshold (const double &new_threshold)
void	setMaxIterations (int new_max_iters)
void	setDxDy (const ossimDpt &dxdy)
Public Member Functions inherited from ossimObject
	ossimObject ()
virtual	~ossimObject ()
virtual ossimString	getShortName () const
virtual ossimString	getLongName () const
virtual ossimString	getDescription () const
virtual ossimString	getClassName () const
virtual RTTItypeid	getType () const
virtual bool	canCastTo (ossimObject *obj) const
virtual bool	canCastTo (const RTTItypeid &id) const
virtual bool	canCastTo (const ossimString &parentClassName) const
virtual bool	isEqualTo (const ossimObject &obj, ossimCompareType compareType=OSSIM_COMPARE_FULL) const
virtual void	accept (ossimVisitor &visitor)
Public Member Functions inherited from ossimReferenced
	ossimReferenced ()
	ossimReferenced (const ossimReferenced &)
ossimReferenced &	operator= (const ossimReferenced &)
void	ref () const
	increment the reference count by one, indicating that this object has another pointer which is referencing it. More...
void	unref () const
	decrement the reference count by one, indicating that a pointer to this object is referencing it. More...
void	unref_nodelete () const
	decrement the reference count by one, indicating that a pointer to this object is referencing it. More...
int	referenceCount () const

Protected Attributes
ossim_float64	m_coefficientsXTerm [4]
ossim_float64	m_coefficientsYTerm [4]
ossim_float64	m_inverseCoefficientsXTerm [4]
ossim_float64	m_inverseCoefficientsYTerm [4]
	TYPE_DATA
Protected Attributes inherited from ossim2dTo2dTransform
double	theConvergenceThreshold
int	theMaxIterations
ossimDpt	theDxDy

Additional Inherited Members
Protected Member Functions inherited from ossim2dTo2dTransform
	ossim2dTo2dTransform ()
virtual	~ossim2dTo2dTransform ()
Protected Member Functions inherited from ossimReferenced
virtual	~ossimReferenced ()

Detailed Description

ossim2dBilinearTransform allows one to specify a set of input points and output points and will fit a bilinear transform to those points.

Function of the form is solved for each
output dimension.

z(x,y) = a + b*x + c*y + d*x*y

We use the ossimLeastSquareBilin solver to solve for the coefficients.

Definition at line 15 of file ossim2dBilinearTransform.h.

Constructor & Destructor Documentation

ossim2dBilinearTransform() [1/4]

ossim2dBilinearTransform::ossim2dBilinearTransform

(

)

Initialize to the identity.

Definition at line 6 of file ossim2dBilinearTransform.cpp.

References m_coefficientsXTerm, m_coefficientsYTerm, m_inverseCoefficientsXTerm, and m_inverseCoefficientsYTerm.

{
   std::fill(m_coefficientsXTerm, m_coefficientsXTerm+4, 0.0);
   std::fill(m_coefficientsYTerm, m_coefficientsYTerm+4, 0.0);
   std::fill(m_inverseCoefficientsXTerm, m_inverseCoefficientsXTerm+4, 0.0);
   std::fill(m_inverseCoefficientsYTerm, m_inverseCoefficientsYTerm+4, 0.0);
   
   // setup identity
   //
   m_coefficientsXTerm[1] = 1.0;
   m_coefficientsYTerm[2] = 1.0;
   m_inverseCoefficientsXTerm[1] = 1.0;
   m_inverseCoefficientsYTerm[2] = 1.0;
}

ossim2dBilinearTransform() [2/4]

ossim2dBilinearTransform::ossim2dBilinearTransform ( const ossimDpt *  input, const ossimDpt *  output, ossim_uint32  arraySize  )

inline

Initialize the transform that best fits the input and output arrays.

If the input and output are well dispersed and are 4 points it should fit exactly. Both arrays should be of equal number of points

Parameters

input	the list of input points
output	the list of output points to transform the input to
arraySize	the number of points for the arrays.

Definition at line 32 of file ossim2dBilinearTransform.h.

   {
      setFromPoints(input, output, arraySize);
   }

ossim2dBilinearTransform() [3/4]

ossim2dBilinearTransform::ossim2dBilinearTransform ( const ossimDpt &  in1, const ossimDpt &  in2, const ossimDpt &  in3, const ossimDpt &  in4, const ossimDpt &  out1, const ossimDpt &  out2, const ossimDpt &  out3, const ossimDpt &  out4  )

inline

Mapping 4 corners to an output 4 corners.

Definition at line 43 of file ossim2dBilinearTransform.h.

   {
      setFromPoints(in1, in2, in3, in4, out1, out2, out3, out4);
   }

ossim2dBilinearTransform() [4/4]

ossim2dBilinearTransform::ossim2dBilinearTransform

(

const ossim2dBilinearTransform &

src

)

Copy constructor.

Definition at line 21 of file ossim2dBilinearTransform.cpp.

References m_coefficientsXTerm, m_coefficientsYTerm, m_inverseCoefficientsXTerm, and m_inverseCoefficientsYTerm.

:ossim2dTo2dTransform(src)
{
   std::copy(src.m_coefficientsXTerm, src.m_coefficientsXTerm+4, m_coefficientsXTerm);
   std::copy(src.m_coefficientsYTerm, src.m_coefficientsYTerm+4, m_coefficientsYTerm);
   std::copy(src.m_inverseCoefficientsXTerm, src.m_inverseCoefficientsXTerm+4, m_inverseCoefficientsXTerm);
   std::copy(src.m_inverseCoefficientsYTerm, src.m_inverseCoefficientsYTerm+4, m_inverseCoefficientsYTerm);
}

Member Function Documentation

dup()

virtual ossimObject* ossim2dBilinearTransform::dup ( ) const

inlinevirtual

Duplication method that duplicates this object.

Reimplemented from ossimObject.

Definition at line 57 of file ossim2dBilinearTransform.h.

{return new ossim2dBilinearTransform(*this);}

forward() [1/2]

virtual void ossim2dBilinearTransform::forward ( const ossimDpt &  input, ossimDpt &  output  ) const

inlinevirtual

forward transform will transform an input point to the output.

Implements ossim2dTo2dTransform.

Definition at line 101 of file ossim2dBilinearTransform.h.

References ossimDpt::x, and ossimDpt::y.

   {
      output.x = (m_coefficientsXTerm[0] + 
                  m_coefficientsXTerm[1]*input.x + 
                  m_coefficientsXTerm[2]*input.y + 
                  m_coefficientsXTerm[3]*input.x*input.y);
      output.y = (m_coefficientsYTerm[0] + 
                  m_coefficientsYTerm[1]*input.x + 
                  m_coefficientsYTerm[2]*input.y + 
                  m_coefficientsYTerm[3]*input.x*input.y);
   }

forward() [2/2]

virtual void ossim2dBilinearTransform::forward ( ossimDpt &  modify_this ) const

inlinevirtual

forward transform will transform an input point to the output and modify the passed in point to the new value

Reimplemented from ossim2dTo2dTransform.

Definition at line 118 of file ossim2dBilinearTransform.h.

References ossimDpt::x, and ossimDpt::y.

   {
      double saveX = modify_this.x;
      modify_this.x = (m_coefficientsXTerm[0] + 
                       m_coefficientsXTerm[1]*modify_this.x + 
                       m_coefficientsXTerm[2]*modify_this.y + 
                       m_coefficientsXTerm[3]*modify_this.x*modify_this.y);
      modify_this.y = (m_coefficientsYTerm[0] + 
                       m_coefficientsYTerm[1]*saveX + 
                       m_coefficientsYTerm[2]*modify_this.y + 
                       m_coefficientsYTerm[3]*saveX*modify_this.y);
   }

inverse() [1/2]

virtual void ossim2dBilinearTransform::inverse ( const ossimDpt &  input, ossimDpt &  output  ) const

inlinevirtual

Inverts the point back to the original input value.

Reimplemented from ossim2dTo2dTransform.

Definition at line 134 of file ossim2dBilinearTransform.h.

References ossimDpt::x, and ossimDpt::y.

   {
      output.x = (m_inverseCoefficientsXTerm[0] + 
                  m_inverseCoefficientsXTerm[1]*input.x + 
                  m_inverseCoefficientsXTerm[2]*input.y + 
                  m_inverseCoefficientsXTerm[3]*input.x*input.y);
      output.y = (m_inverseCoefficientsYTerm[0] + 
                  m_inverseCoefficientsYTerm[1]*input.x + 
                  m_inverseCoefficientsYTerm[2]*input.y + 
                  m_inverseCoefficientsYTerm[3]*input.x*input.y);
   }

inverse() [2/2]

virtual void ossim2dBilinearTransform::inverse ( ossimDpt &  modify_this ) const

inlinevirtual

Inverts the point back to the original input value and modifies the passed in point to the new value.

Reimplemented from ossim2dTo2dTransform.

Definition at line 151 of file ossim2dBilinearTransform.h.

References ossimDpt::x, and ossimDpt::y.

   {
      double saveX = modify_this.x;
      modify_this.x = (m_inverseCoefficientsXTerm[0] + 
                       m_inverseCoefficientsXTerm[1]*modify_this.x + 
                       m_inverseCoefficientsXTerm[2]*modify_this.y + 
                       m_inverseCoefficientsXTerm[3]*modify_this.x*modify_this.y);
      modify_this.y = (m_inverseCoefficientsYTerm[0] + 
                       m_inverseCoefficientsYTerm[1]*saveX + 
                       m_inverseCoefficientsYTerm[2]*modify_this.y + 
                       m_inverseCoefficientsYTerm[3]*saveX*modify_this.y);
   }

loadState()

bool ossim2dBilinearTransform::loadState ( const ossimKeywordlist &  kwl, const char *  prefix = 0  )

virtual

loads the state of this object from a keywordlist.

Reimplemented from ossim2dTo2dTransform.

Definition at line 102 of file ossim2dBilinearTransform.cpp.

References ossimKeywordlist::find(), ossim2dTo2dTransform::loadState(), m_coefficientsXTerm, m_coefficientsYTerm, m_inverseCoefficientsXTerm, m_inverseCoefficientsYTerm, and ossimString::split().

{
   bool result = true;
   ossimString xterm = kwl.find(prefix, "xterm");
   ossimString yterm = kwl.find(prefix, "yterm");
   ossimString inverse_xterm = kwl.find(prefix, "inverse_xterm");
   ossimString inverse_yterm = kwl.find(prefix, "inverse_yterm");
   
   std::vector<ossimString> values;
   xterm.split(values, " ");
   if(values.size() == 4)
   {
      m_coefficientsXTerm[0] = values[0].toDouble();
      m_coefficientsXTerm[1] = values[1].toDouble();
      m_coefficientsXTerm[2] = values[2].toDouble();
      m_coefficientsXTerm[3] = values[3].toDouble();
   }
   else 
   {
      result = false;
   }
   values.clear();
   yterm.split(values, " ");
   if(values.size() == 4)
   {
      m_coefficientsYTerm[0] = values[0].toDouble();
      m_coefficientsYTerm[1] = values[1].toDouble();
      m_coefficientsYTerm[2] = values[2].toDouble();
      m_coefficientsYTerm[3] = values[3].toDouble();
   }
   else 
   {
      result = false;
   }
   values.clear();
   inverse_xterm.split(values, " ");
   if(values.size() == 4)
   {
      m_inverseCoefficientsXTerm[0] = values[0].toDouble();
      m_inverseCoefficientsXTerm[1] = values[1].toDouble();
      m_inverseCoefficientsXTerm[2] = values[2].toDouble();
      m_inverseCoefficientsXTerm[3] = values[3].toDouble();
   }
   else 
   {
      result = false;
   }
   values.clear();
   inverse_yterm.split(values, " ");
   if(values.size() == 4)
   {
      m_inverseCoefficientsYTerm[0] = values[0].toDouble();
      m_inverseCoefficientsYTerm[1] = values[1].toDouble();
      m_inverseCoefficientsYTerm[2] = values[2].toDouble();
      m_inverseCoefficientsYTerm[3] = values[3].toDouble();
   }
   else 
   {
      result = false;
   }

   if(result)
   {
      result = ossim2dTo2dTransform::loadState(kwl, prefix);
   }
   
   return result;
}

operator=()

const ossim2dBilinearTransform& ossim2dBilinearTransform::operator= ( const ossim2dBilinearTransform &  src )

inline

Overloaded operator equal that allows for assignment.

Parameters

src	the src data to copy into this object. It will call the base classes equal operator.

Definition at line 65 of file ossim2dBilinearTransform.h.

References m_coefficientsXTerm, m_coefficientsYTerm, m_inverseCoefficientsXTerm, m_inverseCoefficientsYTerm, and ossim2dTo2dTransform::operator=().

   {
      if(this == &src) return *this;
      
      ossim2dTo2dTransform::operator =(*this); // call base classes equal operator
      std::copy(src.m_coefficientsXTerm, src.m_coefficientsXTerm+4, m_coefficientsXTerm);
      std::copy(src.m_coefficientsYTerm, src.m_coefficientsYTerm+4, m_coefficientsYTerm);
      std::copy(src.m_inverseCoefficientsXTerm, src.m_inverseCoefficientsXTerm+4, m_inverseCoefficientsXTerm);
      std::copy(src.m_inverseCoefficientsYTerm, src.m_inverseCoefficientsYTerm+4, m_inverseCoefficientsYTerm);
      
      return *this;
   }

print()

virtual std::ostream& ossim2dBilinearTransform::print ( std::ostream &  out ) const

inlinevirtual

prints the contents of this object.

Will also cal the base classes print method.

Reimplemented from ossim2dTo2dTransform.

Definition at line 180 of file ossim2dBilinearTransform.h.

References ossim2dTo2dTransform::print().

   {
      ossim2dTo2dTransform::print(out);
      out << "xTerm: " << m_coefficientsXTerm[0] << ", " << m_coefficientsXTerm[1] << ", "
          << m_coefficientsXTerm[2] << ", " << m_coefficientsXTerm[3] << "\n";
      out << "yTerm: " << m_coefficientsYTerm[0] << ", " << m_coefficientsYTerm[1] << ", "
          << m_coefficientsYTerm[2] << ", " << m_coefficientsYTerm[3] << "\n";
      
      out << "xInverseTerm: " << m_inverseCoefficientsXTerm[0] << ", " << m_inverseCoefficientsXTerm[1] << ", "
          << m_inverseCoefficientsXTerm[2] << ", " << m_inverseCoefficientsXTerm[3] << "\n";
      out << "yInverseTerm: " << m_inverseCoefficientsYTerm[0] << ", " << m_inverseCoefficientsYTerm[1] << ", "
          << m_inverseCoefficientsYTerm[2] << ", " << m_inverseCoefficientsYTerm[3] << "\n";
      
      return out;
   }

saveState()

bool ossim2dBilinearTransform::saveState ( ossimKeywordlist &  kwl, const char *  prefix = 0  ) const

virtual

Saves the state of this object.

Reimplemented from ossim2dTo2dTransform.

Definition at line 75 of file ossim2dBilinearTransform.cpp.

References ossimKeywordlist::add(), m_coefficientsXTerm, m_coefficientsYTerm, m_inverseCoefficientsXTerm, m_inverseCoefficientsYTerm, ossim2dTo2dTransform::saveState(), and ossimString::toString().

{
   ossimString xterm = (ossimString::toString(m_coefficientsXTerm[0])
                        +" "+ossimString::toString(m_coefficientsXTerm[1])
                        +" "+ossimString::toString(m_coefficientsXTerm[2])
                        +" "+ossimString::toString(m_coefficientsXTerm[3]));
   ossimString yterm = (ossimString::toString(m_coefficientsYTerm[0])
                        +" "+ossimString::toString(m_coefficientsYTerm[1])
                        +" "+ossimString::toString(m_coefficientsYTerm[2])
                        +" "+ossimString::toString(m_coefficientsYTerm[3]));
   ossimString inverse_xterm = (ossimString::toString(m_inverseCoefficientsXTerm[0])
                        +" "+ossimString::toString(m_inverseCoefficientsXTerm[1])
                        +" "+ossimString::toString(m_inverseCoefficientsXTerm[2])
                        +" "+ossimString::toString(m_inverseCoefficientsXTerm[3]));
   ossimString inverse_yterm = (ossimString::toString(m_inverseCoefficientsYTerm[0])
                        +" "+ossimString::toString(m_inverseCoefficientsYTerm[1])
                        +" "+ossimString::toString(m_inverseCoefficientsYTerm[2])
                        +" "+ossimString::toString(m_inverseCoefficientsYTerm[3]));
   
   kwl.add(prefix, "xterm", xterm, true);
   kwl.add(prefix, "yterm", yterm, true);
   kwl.add(prefix, "inverse_xterm", inverse_xterm, true);
   kwl.add(prefix, "inverse_yterm", inverse_yterm, true);
   return ossim2dTo2dTransform::saveState(kwl, prefix);
}

setFromPoints() [1/2]

void ossim2dBilinearTransform::setFromPoints	(	const ossimDpt &	in1,
		const ossimDpt &	in2,
		const ossimDpt &	in3,
		const ossimDpt &	in4,
		const ossimDpt &	out1,
		const ossimDpt &	out2,
		const ossimDpt &	out3,
		const ossimDpt &	out4
	)

Mapping 4 corners to an output 4 corners.

Will use the ossimLeastSquareBilin class to solve the bilinear coefficients that maps the given input points to the output points.

Definition at line 30 of file ossim2dBilinearTransform.cpp.

{
   ossimDpt input[4];
   ossimDpt output[4];
   
   input[0] = in1;
   input[1] = in2;
   input[2] = in3;
   input[3] = in4;
   
   output[0] = out1;
   output[1] = out2;
   output[2] = out3;
   output[3] = out4;
   
   setFromPoints(&input[0], &output[0], 4);
}

setFromPoints() [2/2]

void ossim2dBilinearTransform::setFromPoints	(	const ossimDpt *	input,
		const ossimDpt *	output,
		ossim_uint32	arraySize
	)

Initialize the transform that best fits the input and output arrays.

If the input and output are well dispersed and are 4 points it should fit exactly. Both arrays should be of equal number of points

Parameters

input	the list of input points
output	the list of output points to transform the input to
arraySize	the number of points for the arrays.

Definition at line 49 of file ossim2dBilinearTransform.cpp.

References ossimLeastSquaresBilin::addSample(), ossimLeastSquaresBilin::getLSParms(), m_coefficientsXTerm, m_coefficientsYTerm, m_inverseCoefficientsXTerm, m_inverseCoefficientsYTerm, ossimLeastSquaresBilin::solveLS(), x, and y.

{
   ossimLeastSquaresBilin inx;
   ossimLeastSquaresBilin inversex;
   ossimLeastSquaresBilin iny;
   ossimLeastSquaresBilin inversey;
   ossim_uint32 idx = 0;
   for(idx=0; idx < arraySize; ++idx)
   {
      inx.addSample(input[idx].x, input[idx].y, output[idx].x);
      inversex.addSample(output[idx].x, output[idx].y, input[idx].x);
      iny.addSample(input[idx].x, input[idx].y, output[idx].y);
      inversey.addSample(output[idx].x, output[idx].y, input[idx].y);
   }
   inx.solveLS();
   inversex.solveLS();
   iny.solveLS();
   inversey.solveLS();
   inx.getLSParms(m_coefficientsXTerm[0], m_coefficientsXTerm[1], m_coefficientsXTerm[2], m_coefficientsXTerm[3]);
   iny.getLSParms(m_coefficientsYTerm[0], m_coefficientsYTerm[1], m_coefficientsYTerm[2], m_coefficientsYTerm[3]);
   inversex.getLSParms(m_inverseCoefficientsXTerm[0], m_inverseCoefficientsXTerm[1], m_inverseCoefficientsXTerm[2], m_inverseCoefficientsXTerm[3]);
   inversey.getLSParms(m_inverseCoefficientsYTerm[0], m_inverseCoefficientsYTerm[1], m_inverseCoefficientsYTerm[2], m_inverseCoefficientsYTerm[3]);
}

Member Data Documentation

m_coefficientsXTerm

ossim_float64 ossim2dBilinearTransform::m_coefficientsXTerm[4]

protected

Definition at line 197 of file ossim2dBilinearTransform.h.

Referenced by loadState(), operator=(), ossim2dBilinearTransform(), saveState(), and setFromPoints().

m_coefficientsYTerm

ossim_float64 ossim2dBilinearTransform::m_coefficientsYTerm[4]

protected

Definition at line 198 of file ossim2dBilinearTransform.h.

Referenced by loadState(), operator=(), ossim2dBilinearTransform(), saveState(), and setFromPoints().

m_inverseCoefficientsXTerm

ossim_float64 ossim2dBilinearTransform::m_inverseCoefficientsXTerm[4]

protected

Definition at line 200 of file ossim2dBilinearTransform.h.

Referenced by loadState(), operator=(), ossim2dBilinearTransform(), saveState(), and setFromPoints().

m_inverseCoefficientsYTerm

ossim_float64 ossim2dBilinearTransform::m_inverseCoefficientsYTerm[4]

protected

Definition at line 201 of file ossim2dBilinearTransform.h.

Referenced by loadState(), operator=(), ossim2dBilinearTransform(), saveState(), and setFromPoints().

TYPE_DATA

ossim2dBilinearTransform::TYPE_DATA

protected

Definition at line 202 of file ossim2dBilinearTransform.h.

---

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

• ossim2dBilinearTransform.h
• ossim2dBilinearTransform.cpp