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#include <Image_Convertor.ixx>
#include <Image_PseudoColorImage.hxx>
#include <Image_ColorImage.hxx>
#include <Image_LookupTable.hxx>
#include <Aspect_ColorMapEntry.hxx>
#ifdef TRACE
static int Verbose = 0 ;
#endif
Image_Convertor::Image_Convertor() { myDitheringMethod = Image_DM_NearestColor;}
void Image_Convertor::SetDitheringMethod( const Image_DitheringMethod Method )
{ myDitheringMethod = Method ; }
Handle(Image_PseudoColorImage) Image_Convertor::Convert(
const Handle(Image_ColorImage)& aImage,
const Handle(Aspect_ColorMap)& aColorMap ) const
{ Handle(Image_PseudoColorImage) ret_image = NULL ;
if ( myDitheringMethod == Image_DM_NearestColor ) {
ret_image = NearestDithering( aImage, aColorMap ) ;
}
else if ( myDitheringMethod == Image_DM_ErrorDiffusion ) {
ret_image = ErrorDiffusionDithering( aImage, aColorMap ) ;
}
return ret_image ;
}
Handle(Image_PseudoColorImage) Image_Convertor::Convert(
const Handle(Image_PseudoColorImage)& aImage,
const Handle(Aspect_ColorMap)& aColorMap ) const
{ Handle(Image_PseudoColorImage) ret_image = NULL ;
if ( myDitheringMethod == Image_DM_NearestColor ) {
ret_image = NearestDithering( aImage, aColorMap ) ;
}
else if ( myDitheringMethod == Image_DM_ErrorDiffusion ) {
ret_image = ErrorDiffusionDithering( aImage, aColorMap ) ;
}
return ret_image ;
}
Handle(Image_ColorImage) Image_Convertor::Convert(
const Handle(Image_PseudoColorImage)& aImage ) const
{ Handle(Image_ColorImage) ret_image = NULL ;
Standard_Integer x, y, val, lastval ;
Quantity_Color aColor ;
Standard_Integer UpX = aImage->UpperX() ;
Standard_Integer UpY = aImage->UpperY() ;
ret_image = new Image_ColorImage( aImage->LowerX(), aImage->LowerY(),
aImage->Width() , aImage->Height() ) ;
lastval = aImage->Pixel(aImage->LowerX(), aImage->LowerY() ).Value() ;
aColor = aImage->ColorMap()->FindEntry(lastval).Color() ;
for ( y = aImage->LowerY() ; y <= UpY ; y++ ) {
for ( x = aImage->LowerX() ; x <= UpX ; x++ ) {
val = aImage->Pixel(x,y).Value() ;
if ( lastval != val ) {
lastval = val ;
aColor = aImage->ColorMap()->FindEntry(lastval).Color() ;
}
ret_image->SetPixel( x, y, aColor );
}
}
return( ret_image ) ;
}
Handle(Image_PseudoColorImage) Image_Convertor::NearestDithering(
const Handle(Image_ColorImage)& aImage,
const Handle(Aspect_ColorMap)& aColorMap ) const
{ Handle(Image_PseudoColorImage) ret_image = NULL ;
Standard_Integer x, y, index ;
Quantity_Color lastval, val ;
Standard_Integer UpX = aImage->UpperX() ;
Standard_Integer UpY = aImage->UpperY() ;
ret_image = new Image_PseudoColorImage( aImage->LowerX(), aImage->LowerY(),
aImage->Width() , aImage->Height(),
aColorMap );
lastval = aImage->PixelColor(aImage->LowerX(),aImage->LowerY()) ;
index = aColorMap->NearestEntry( lastval ).Index() ;
for ( y = aImage->LowerY() ; y <= UpY ; y++ ) {
for ( x = aImage->LowerX() ; x <= UpX ; x++ ) {
val = aImage->PixelColor(x,y) ;
if ( !( val == lastval ) ) {
lastval = val ;
index = aColorMap->NearestEntry( lastval ).Index() ;
}
ret_image->SetPixel( x, y, index ) ;
}
}
return( ret_image ) ;
}
Handle(Image_PseudoColorImage) Image_Convertor::NearestDithering(
const Handle(Image_PseudoColorImage)& aImage,
const Handle(Aspect_ColorMap)& aColorMap ) const
{ Handle(Image_PseudoColorImage) ret_image = NULL ;
Standard_Integer x,y, val, lastval, index ;
Standard_Integer UpX = aImage->UpperX() ;
Standard_Integer UpY = aImage->UpperY() ;
Image_LookupTable ColorMapLookup ;
Aspect_ColorMapEntry aEntry ;
Standard_Integer i, size ;
for ( i = 1 , size = aImage->ColorMap()->Size() ; i <= size ; i++ ) {
aEntry = aImage->ColorMap()->Entry(i) ;
index = aColorMap->NearestEntry( aEntry.Color() ).Index() ;
ColorMapLookup.Bind( aEntry.Index(), index ) ;
}
ret_image = new Image_PseudoColorImage( aImage->LowerX(), aImage->LowerY(),
aImage->Width() , aImage->Height(),
aColorMap );
lastval = aImage->Pixel( aImage->LowerX(), aImage->LowerY() ).Value() ;
index = ColorMapLookup.Find( lastval ).Value() ;
for ( y = aImage->LowerY() ; y <= UpY ; y++ ) {
for ( x = aImage->LowerX() ; x <= UpX ; x++ ) {
val = aImage->Pixel(x,y).Value() ;
if ( val != lastval ) {
lastval = val ;
index = ColorMapLookup.Find( lastval ).Value() ;
}
ret_image->SetPixel( x, y, index ) ;
}
}
return( ret_image ) ;
}
static Standard_Boolean ManageLastKernelError = 1 ;
static struct {
Standard_Real v ;
Standard_Integer dx, dy ;
} Kernel[4] = { { 7./16., 1, 0 },
{ 3./16., -1, 1 },
{ 5./16., 0, 1 },
{ 1./16., 1, 1 } } ;
Handle(Image_PseudoColorImage) Image_Convertor::ErrorDiffusionDithering(
const Handle(Image_PseudoColorImage)& RefImage,
const Handle(Aspect_ColorMap)& aColorMap ) const
{ Handle(Image_PseudoColorImage) ret_image = NULL ;
Standard_Integer UpX = RefImage->UpperX() ;
Standard_Integer UpY = RefImage->UpperY() ;
Standard_Integer LowX = RefImage->LowerX() ;
Standard_Integer LowY = RefImage->LowerY() ;
Standard_Integer x,y, index, i, nx,ny ;
Standard_Integer val, lastval ;
Standard_Integer Error, ErrorDiff, pix, npix, MinIndex, MaxIndex ;
Aspect_IndexPixel aPixel ;
Image_LookupTable ColorMapLookup ;
Aspect_ColorMapEntry aEntry ;
Standard_Integer size ;
MaxIndex = MinIndex = RefImage->ColorMap()->Entry(1).Index() ;
for ( i = 1 , size = RefImage->ColorMap()->Size() ; i <= size ; i++ ) {
aEntry = RefImage->ColorMap()->Entry(i) ;
MinIndex = Min( aEntry.Index(), MinIndex ) ;
MaxIndex = Max( aEntry.Index(), MaxIndex ) ;
index = aColorMap->NearestEntry( aEntry.Color() ).Index() ;
ColorMapLookup.Bind( aEntry.Index(), index ) ;
}
Handle(Image_PseudoColorImage) aImage =
Handle(Image_PseudoColorImage)::DownCast( RefImage->Dup() ) ;
ret_image = new Image_PseudoColorImage( aImage->LowerX(), aImage->LowerY(),
aImage->Width() , aImage->Height(),
aColorMap );
lastval = aImage->Pixel( aImage->LowerX(), aImage->LowerY() ).Value() ;
index = ColorMapLookup.Find( lastval ).Value() ;
for ( y = aImage->LowerY() ; y <= UpY ; y++ ) {
for ( x = aImage->LowerX() ; x <= UpX ; x++ ) {
val = aImage->Pixel(x,y).Value() ;
if ( ! ( val == lastval ) ) {
lastval = val ;
index = ColorMapLookup.Find( lastval ).Value() ;
}
ErrorDiff = Error = val - index ;
#ifdef TRACE
if ( Verbose > 3 )
cout << "ErrorDiffusion : " << Error << endl << flush ;
#endif
if ( Error != 0 ) {
for ( i = 0 ; i < 4 ; i++ ) {
nx = x+Kernel[i].dx ;
ny = y+Kernel[i].dy ;
if ( nx >= LowX && nx <= UpX &&
ny >= LowY && ny <= UpY ) {
aImage->Pixel( nx, ny, aPixel ) ;
pix = aPixel.Value() ;
if ( ManageLastKernelError && i == 3 ) {
// Last one
npix = pix + ErrorDiff ;
}
else {
npix = pix + Standard_Integer( Kernel[i].v * Error ) ;
}
// ErrorDiffusion may produce Pixel out of ColorMap
// Clamp value to min max of ColorMap
npix = Max( npix, MinIndex ) ;
npix = Min( npix, MaxIndex ) ;
ErrorDiff -= ( npix - pix ) ;
#ifdef TRACE
if ( Verbose > 2 && i == 3 ) {
cout << "ErrorDiffusion Last Error: " <<
(ErrorDiff-( Kernel[i].v*Error)) <<endl<<flush ;
}
#endif
aPixel.SetValue( npix ) ;
aImage->SetPixel( nx, ny, aPixel ) ;
}
}
}
ret_image->SetPixel( x, y, index ) ;
}
}
return( ret_image ) ;
}
Handle(Image_PseudoColorImage) Image_Convertor::ErrorDiffusionDithering(
const Handle(Image_ColorImage)& RefImage,
const Handle(Aspect_ColorMap)& aColorMap ) const
{ Handle(Image_PseudoColorImage) ret_image = NULL ;
Standard_Integer UpX = RefImage->UpperX() ;
Standard_Integer UpY = RefImage->UpperY() ;
Standard_Integer LowX = RefImage->LowerX() ;
Standard_Integer LowY = RefImage->LowerY() ;
Standard_Integer x,y, index, i, nx,ny ;
Quantity_Color val, lastval, NewCol ;
Aspect_ColorMapEntry aEntry ;
Aspect_ColorPixel aPixel ;
Standard_Real RedError, GreenError, BlueError, r,g,b,cr,cg,cb ;
Standard_Real RedDiffError, GreenDiffError, BlueDiffError ;
Handle(Image_ColorImage) aImage =
Handle(Image_ColorImage)::DownCast( RefImage->Dup() ) ;
ret_image = new Image_PseudoColorImage( aImage->LowerX(), aImage->LowerY(),
aImage->Width() , aImage->Height(),
aColorMap );
lastval = aImage->PixelColor( aImage->LowerX(), aImage->LowerY() ) ;
aEntry = aColorMap->NearestEntry( lastval ) ;
index = aEntry.Index() ;
for ( y = aImage->LowerY() ; y <= UpY ; y++ ) {
for ( x = aImage->LowerX() ; x <= UpX ; x++ ) {
val = aImage->PixelColor(x,y) ;
if ( ! ( val == lastval ) ) {
lastval = val ;
aEntry = aColorMap->NearestEntry( lastval ) ;
index = aEntry.Index() ;
}
RedDiffError = RedError = val.Red() - aEntry.Color().Red() ;
GreenDiffError = GreenError = val.Green() - aEntry.Color().Green() ;
BlueDiffError = BlueError = val.Blue() - aEntry.Color().Blue() ;
#ifdef TRACE
if ( Verbose > 3 )
cout << "ErrorDiffusion : " << RedError << "," <<
GreenError << "," <<
BlueError << "," << endl << flush ;
#endif
if ( RedError != 0. && GreenError != 0. && BlueError != 0. ) {
for ( i = 0 ; i < 4 ; i++ ) {
nx = x+Kernel[i].dx ;
ny = y+Kernel[i].dy ;
if ( nx >= LowX && nx <= UpX &&
ny >= LowY && ny <= UpY ) {
aImage->Pixel( nx, ny, aPixel ) ;
aPixel.Value().Values( r,g,b, Quantity_TOC_RGB ) ;
if ( ManageLastKernelError && i == 3 ) {
// Last one
cr = r + RedDiffError ;
cg = g + GreenDiffError ;
cb = b + BlueDiffError ;
}
else {
cr = r + ( Kernel[i].v * RedError ) ;
cg = g + ( Kernel[i].v * GreenError ) ;
cb = b + ( Kernel[i].v * BlueError ) ;
}
// ErrorDiffusion may produce Pixel out of ColorMap
// Clamp Color
cr = Max( cr, 0. ) ; cr = Min( cr, 1. ) ;
cg = Max( cg, 0. ) ; cg = Min( cg, 1. ) ;
cb = Max( cb, 0. ) ; cb = Min( cb, 1. ) ;
RedDiffError -= ( cr - r ) ;
GreenDiffError -= ( cg - g ) ;
BlueDiffError -= ( cb - b ) ;
#ifdef TRACE
if ( Verbose > 2 && i == 3 ) {
cout << "ErrorDiffusion Last Error: " <<
RedDiffError << "," <<
GreenDiffError << "," <<
BlueDiffError << "," << endl << flush ;
}
#endif
NewCol.SetValues( cr,cg,cb, Quantity_TOC_RGB ) ;
aPixel.SetValue( NewCol ) ;
aImage->SetPixel( nx, ny, aPixel ) ;
}
}
}
ret_image->SetPixel( x, y, index ) ;
}
}
return( ret_image ) ;
}
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