#pragma once
#define BOUND(x,a,b) (((x) <= (a)) ? (a) : (((x) > (b)) ? (b) : (x)))
#define PS_MAX_DEPTH 4
// Based on Eran Yariv's TwoPassScale, modified for speed, bug fixes, and variable depths.
// Does 2 pass scaling of bitmaps
// Template based, can use various methods for interpolation.
// Could certainly be improved.
// to use:
// C2PassScale ScaleEngine;
// ScaleEngine.Scale ((UCHAR *)dibSrc.GetBits(), // A pointer to the source bitmap bits
// depth, // The size of a single pixel in bytes (both source and scaled image)
// dibSrc.Width(), // The width of a line of the source image to scale in pixels
// dibSrc.WidthBytes(), // The width of a single line of the source image in bytes (to allow for padding, etc.)
// dibSrc.Height(), // The height of the source image to scale in pixels.
// (UCHAR *)GetBits(), // A pointer to a buffer to hold the ecaled image
// Width(), // The desired width of a line of the scaled image in pixels
// WidthBytes(), // The width of a single line of the scaled image in bytes (to allow for padding, etc.)
// Height()); // The desired height of the scaled image in pixels.
// or AllocAndScale()
// Modified 1-17-05 to use more integer math -- much faater. [JRM]
class CGenericFilter
{
public:
CGenericFilter (double dWidth) : m_dWidth (dWidth) {}
virtual ~CGenericFilter() {}
double GetWidth() { return m_dWidth; }
void SetWidth (double dWidth) { m_dWidth = dWidth; }
virtual double Filter (double dVal) = 0;
protected:
#define FILTER_PI double (3.1415926535897932384626433832795)
#define FILTER_2PI double (2.0 * 3.1415926535897932384626433832795)
#define FILTER_4PI double (4.0 * 3.1415926535897932384626433832795)
double m_dWidth;
};
class CBoxFilter : public CGenericFilter
{
public:
CBoxFilter (double dWidth = double(0.5)) : CGenericFilter(dWidth) {}
virtual ~CBoxFilter() {}
double Filter (double dVal) { return (fabs(dVal) <= m_dWidth ? 1.0 : 0.0); }
};
class CBilinearFilter : public CGenericFilter
{
public:
CBilinearFilter (double dWidth = double(1.0)) : CGenericFilter(dWidth) {}
virtual ~CBilinearFilter() {}
double Filter (double dVal)
{
dVal = fabs(dVal);
return (dVal < m_dWidth ? m_dWidth - dVal : 0.0);
}
};
class CGaussianFilter : public CGenericFilter
{
public:
CGaussianFilter (double dWidth = double(3.0)) : CGenericFilter(dWidth) {}
virtual ~CGaussianFilter() {}
double Filter (double dVal)
{
if (fabs (dVal) > m_dWidth)
{
return 0.0;
}
return exp (-dVal * dVal / 2.0) / sqrt (FILTER_2PI);
}
};
class CHammingFilter : public CGenericFilter
{
public:
CHammingFilter (double dWidth = double(0.5)) : CGenericFilter(dWidth) {}
virtual ~CHammingFilter() {}
double Filter (double dVal)
{
if (fabs (dVal) > m_dWidth)
{
return 0.0;
}
double dWindow = 0.54 + 0.46 * cos (FILTER_2PI * dVal);
double dSinc = (dVal == 0) ? 1.0 : sin (FILTER_PI * dVal) / (FILTER_PI * dVal);
return dWindow * dSinc;
}
};
class CBlackmanFilter : public CGenericFilter
{
public:
CBlackmanFilter (double dWidth = double(0.5)) : CGenericFilter(dWidth) {}
virtual ~CBlackmanFilter() {}
double Filter (double dVal)
{
if (fabs (dVal) > m_dWidth)
{
return 0.0;
}
double dN = 2.0 * m_dWidth + 1.0;
return 0.42 + 0.5 * cos (FILTER_2PI * dVal / ( dN - 1.0 )) +
0.08 * cos (FILTER_4PI * dVal / ( dN - 1.0 ));
}
};
typedef struct
{
unsigned int*Weights; // Normalized weights of neighboring pixels
int Left,Right; // Bounds of source pixels window
} ContributionType; // Contirbution information for a single pixel
typedef struct
{
ContributionType *ContribRow; // Row (or column) of contribution weights
UINT WindowSize, // Filter window size (of affecting source pixels)
LineLength; // Length of line (no. or rows / cols)
} LineContribType; // Contribution information for an entire line (row or column)
typedef BOOL (*ProgressAnbAbortCallBack)(BYTE bPercentComplete);
template <class FilterClass>
class C2PassScale
{
public:
C2PassScale (ProgressAnbAbortCallBack callback = NULL) :
m_Callback (callback) {m_byteDepth = 3;}
virtual ~C2PassScale() {}
UCHAR * AllocAndScale (
UCHAR *pOrigImage,
UINT pixelBytes,
UINT uOrigWidth,
UINT uOrigWidthBytes,
UINT uOrigHeight,
UINT uNewWidth,
UINT uNewWidthBytes,
UINT uNewHeight);
UCHAR * Scale (
UCHAR *pOrigImage,
UINT pixelBytes,
UINT uOrigWidth,
UINT uOrigWidthBytes,
UINT uOrigHeight,
UCHAR *pDstImage,
UINT uNewWidth,
UINT uNewWidthBytes,
UINT uNewHeight);
int m_byteDepth;
private:
ProgressAnbAbortCallBack m_Callback;
BOOL m_bCanceled;
LineContribType *AllocContributions ( UINT uLineLength,
UINT uWindowSize);
void FreeContributions (LineContribType * p);
LineContribType *CalcContributions ( UINT uLineSize,
UINT uSrcSize,
double dScale);
void ScaleRow ( UCHAR *pSrc,
UINT uSrcWidth,
UINT uSrcWidthBytes,
UCHAR *pRes,
UINT uResWidth,
UINT uDstWidthBytes,
UINT uRow,
LineContribType *Contrib);
void HorizScale ( UCHAR *pSrc,
UINT uSrcWidth,
UINT uSrcWidthBytes,
UINT uSrcHeight,
UCHAR *pDst,
UINT uResWidth,
UINT uResWidthBytes);
void ScaleCol ( UCHAR *pSrc,
UINT uSrcWidth,
UINT uSrcWidthBytes,
UCHAR *pRes,
UINT uResWidth,
UINT uResWidthBytes,
UINT uResHeight,
UINT uCol,
LineContribType *Contrib);
void VertScale ( UCHAR *pSrc,
UINT uSrcWidth,
UINT uSrcWidthBytes,
UINT uSrcHeight,
UCHAR *pDst,
UINT uResHeight);
};
template <class FilterClass>
LineContribType *
C2PassScale<FilterClass>
::AllocContributions (UINT uLineLength, UINT uWindowSize)
{
LineContribType *res = new LineContribType;
// Init structure header
res->WindowSize = uWindowSize;
res->LineLen
