Filter Library

Camera

Interface Physics

ScanFilterDifferential.h

/*
 * ScanFilterDifferential.h - frame by frame differentiation.
 *
 * This file is part of the Camera Filter Library.
 * Computer Aided Measurement Environment for Realtime Atomic imaging (Camera)
 *
 * Copyright (C) 2004-2005, Leiden Probe Microscopy.
 * Copyright (C) 2004-2005, Universiteit Leiden.
 *
 * Authors: M. Seynen (original), Martin J. Moene
 *
 * $Id: ScanFilterDifferential.h 202 2005-05-12 11:00:48Z moene $
 */

#ifndef CFL_SCANFILTERDIFFERENTIAL_H
#define CFL_SCANFILTERDIFFERENTIAL_H

#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000

#include <cfl/ScanFilter.h>             // for base class
#include <cfl/ScanBaseBuffer.h>         // for ValueType

/**
 * \addtogroup cfl_filterdifferential Frame by Frame Differential Filter
 * \brief frame by frame differential filter.
 *

<h3>Purpose</h3>

Differentiate one frame at a time.

<h3>Description</h3>

This filter differentiates one frame at a time. It uses two neihgbor
pixels in the x-direction and two neihgbor pixels in the y-direction to
calculate the delta at each position. 

In addition to this an angle \f$alpha\f$ is used to weigh the direction of
differentiation in the x- and y-direction. This makes the "light source" to
appear fom a certain direction.

<h3>Algorithm</h3>

\f{eqnarray*}
   \textrm{B}{ij} & = & \textrm{cos}\ \alpha\ ( \textrm{A}{ij_{+1}} - \textrm{A}{ij_{-1}} )\ /\ 2 \\
                  & + & \textrm{sin}\ \alpha\ ( \textrm{A}{i_{+1}j} - \textrm{A}{i_{-1}j} )\ /\ 2
\f}

<h3>Examples</h3>
Try to find some interesting pictures for most filters.

<h3>Contact</h3>
Dipl.phys. M.J. Rost<br>
Huygens Laboratorium<br>
Universiteit Leiden<br>
Niels Bohrweg 2<br>
2333 CA Leiden, The Netherlands<br>
<br>
Tel: +31 71 5275600<br>
Fax: +31 71 5275404<br>
<br>
E-mail: rost@physics.LeidenUniv.nl<br>
Web: http://www.geocities.com/marcel_rost/<br>

 *
 * @{
 */

DECLARE_CLASS( CScanFilterDifferential );       // create various types

/**
 * \brief frame-by-frame differential filter.
 *
 */
class CScanFilterDifferential : public CScanFilter
{
friend  class CFilterDlg_Differential;

public:
   /**
    * the value type.
    */
   typedef CScanBaseBuffer::ValueType ValueType;

   /**
    * the parent class.
    */
   typedef CScanFilter Super;

   ///
   /// \name Construction
   /// @{

   /**
    * default constructor.
    */
   CScanFilterDifferential();

   /**
    * destructor.
    */
   virtual ~CScanFilterDifferential();

   /// @}
   /// \name Camera--Filter Interface
   /// @{

   /**
    * \brief configure filter with settings as provided by the application on the
    * filterlist window (e.g. via registry); see also CScanFilterNull::ReadFilterSettings().
    */
   virtual void ReadFilterSettings( );

   /**
    * \brief save filter settings e.g. for use with the filterlist window (e.g. via registry);
    * see also ReadFilterSettings().
    */
   virtual void WriteFilterSettings( ) const;

   /**
    * provide current filter parameter(s) for filter-scripting capture
    * in the main application;
    * see also CScanFilterNull::GetParameters().
    */
   virtual LPCTSTR GetParameters() const;

   /**
    * set parameters for filter-script execution of filter;
    * see also CScanFilterNull::SetParameters().
    */
   virtual BOOL SetParameters( LPCTSTR lpParameters );

   /**
    * start filter dialog to edit parameters; no filter operations;
    * see also CScanFilterNull::EditModeless().
    */
   virtual BOOL EditModeless( CWnd *pParentWnd );

   /**
    * create filter dialog and pre Apply() filter to view result;
    * see also CScanFilterNull::RunModeless().
    */
   virtual BOOL RunModeless( CWnd *pParentWnd, CDocument *pDoc );

   /**
    * check parameters, take care of a properly sized output buffer,
    * set its name and copy filter parameters and process;
    * see also CScanFilterNull::ApplyCore().
    */
   virtual BOOL Apply();

   /// @}
   /// \name Predicates
   /// @{

   /// @}
   /// \name Accessors
   /// @{

   /// @}
   /// \name Mutators
   /// @{

   /// @}

public:
   /**
    * the filter name.
    */
   static LPCTSTR m_lpcsFilterName;

   /**
    * the class short filtername.
    */
   static LPCTSTR m_lpcsShortFilterName;

   /**
    * the default angle for differentiation.
    */
   static const int def_nAngle;

protected:
   /**
    * store or retrieve the object's settings.
    */
   virtual void Serialize( CArchive& ar );
   DECLARE_SERIAL( CScanFilterDifferential )

   /**
    * differentiate the frame part at the given offset (L2R, R2L frame part).
    */
   void Differentiate( DWORD dwOffset );

protected:
   /**
    * the current angle for differentiation.
    */
   int  m_nAngle;
};

/// @}  cfl_filterdifferential

#endif // CFL_SCANFILTERDIFFERENTIAL_H

/*
 * end of file
 */

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