size_t max_x( tImgPlanar const& im );
     size_t min_x( tImgPlanar const& im );
     size_t max_y( tImgPlanar const& im );
     size_t min_y( tImgPlanar const& im );


     //testpattern
     void fill( tImgPlanar& img, uint32_t val ) ;
     void rampx( tImgPlanar& img, size_t start = 1, size_t end = 255 );
     void rampy( tImgPlanar& img, size_t start = 1, size_t end = 255 );
     void rampxy( tImgPlanar& img, size_t start = 1, size_t end = 255 );
     bool rectangle( tImgPlanar& img,  uint32_t val, uint32_xy pos, uint32_xy size ) ;

     // rimg_math, insert
     bool Insert( const tImgViewPlanar& from, tImgPlanar& to, int32_xy xy ) ;


     // ring_math, aoi
     bool ExtractAoi( tImgViewPlanar const& s, tImgPlanar& t, tAoi& aoi ) ;


     // helper
     void ExtendImage( const tImgViewPlanar& in, tImgPlanar& extended, size_t kernel ) ;
     void ToExtendedImage( const tImgViewPlanar& in, tImgPlanar& out, int border ) ;
     void FitToImgPlanar( tIntPlane32 const& hor , tImgPlanar& img, int32_xy minmax ) ;
     void ToExtendedImageArea( const tPlane8& in, tPlane8& out, int border ) ;
     void ToExtendedImageArea( const tImgViewPlanar& in,
                               tImgPlanar& extended, size_t border ) ;

     // lowpass
     void Gauss3( tImgPlanar& img );
     void Gauss( tImgPlanar& img, int ker_size ) ;
     void Gauss1( tImgPlanar& img, int ker_size ) ;

     // edges
     void Sobel( tImgViewPlanar const& source, tImgPlanar& abs, tImgPlanar& orient ) ;

     // bin edit

     void Add( tImgPlanar& sum,   const tImgViewPlanar& summand,  int constant ) ;
     void Add( tImgPlanar& source, int const1 ) ;


     void Subtract( tImgPlanar& target, const tImgViewPlanar& second, int const1 = 0 ) ;
     void Subtract( tImgPlanar& target, int constant ) ;

     void Or( tImgPlanar& target,  const tImgViewPlanar& or_ ) ;
     void Xor( tImgPlanar& target, const tImgViewPlanar& xor_ ) ;

     void BitwiseAnd( tImgPlanar& target, const tImgViewPlanar& xor_ ) ;

     void Average( tImgPlanar& target, const tImgViewPlanar& source ) ;
     void LogicalAnd( tImgPlanar& target, const tImgViewPlanar& second ) ;
     void AndBitwiseNot( tImgPlanar& target, const tImgViewPlanar& second ) ;


     void SubtractShift( tImgPlanar& target, const tImgViewPlanar& sub, int c , int shift ) ;
     void Scale( tImgPlanar& source, int scale ) ;
     void Multiplicate( tImgPlanar& source,  int factor ) ;


     vminmax Maximum( tImgPlanar& source ) ;
     vminmax Minimum( tImgPlanar& source ) ;

     void Normalize( tImgPlanar& source, Dword norm ) ;

     void CompareBinWithGray( tImgViewPlanar const& gray, tImgPlanar& bin, uint32_t thre, uint32_t c ) ;
     void BinMaskGray( tImgViewPlanar const& gray, tImgPlanar& bin, uint32_t color ) ;
     void Invert( tImgPlanar& gray ) ;


     bool Closing( tImgPlanar& im, int strength, int color );
     bool Opening( tImgPlanar& im, int strength, int color );
     bool Dilate( tImgPlanar& im, int strength, int color );
     bool Erode( tImgPlanar& im, int strength, int color );
     void BinEdit( tImgPlanar& im, int strength, int color, int edit_case );

     bool Closing( tPlane8& im, int strength, int color );
     bool Opening( tPlane8& im, int strength, int color );
     bool Dilate( tPlane8& im, int strength, int color );
     bool Erode( tPlane8& im, int strength, int color );
     bool BinEdit( tPlane8& im, int strength, int color, int edit_case );


     // rimg_graph
     void DrawText( tImgPlanar& img, uint32_xy xy, const string& text, vcolors const& colors ) ;
     void Line( tImgPlanar& img,  int32_xy from, int32_xy to, vcolors const& colors ) ;
     void Circle( tImgPlanar& img, int32_xy xy, int r, vcolors const& colors ) ;
     void FilledCircle( tImgPlanar& img, int32_xy xy, int r, vcolors const& colors ) ;
     void VerticalLine( tImgPlanar& img,  int xpos, vcolors const& colors ) ;
     void HorizontalLine( tImgPlanar& img,  int xpos, vcolors const& colors ) ;
     void WedgeHorizontal( tImgPlanar& img,  int sy ) ;
     void WedgeVertical( tImgPlanar& img,  int sy ) ;

     void OrthogonalCross( tImgPlanar& img, tixy pos, int size, vcolors const& colors ) ;
     void DiagonalCross( tImgPlanar& img, tixy xy, int const& c ) ;

     void DrawPixelList( tImgPlanar& img, std::vector<int32_xy> v,  uint32_t val ) ;
     std::vector<uint32_t> GetLinePixels( tImgPlanar const& img, uint32_xy from, uint32_xy to ) ;
     int GetLinePixels( tImgPlanar const& img, uint32_xy from, uint32_xy to, std::vector<uint32_t> &v ) ;


     // in rimg_median.cpp
     void Median( tPlane8& im, uint32_t kernel ) ;
     void Median( tImgPlanar& source, uint32_t kernel );

     void Rank( tPlane8 const& im, tPlane8& min_img, tPlane8& max_img, int kernel ) ;
     void Rank( tImgViewPlanar const& source,  tImgPlanar& min_img,  tImgPlanar& max_img, uint32_t kernel ) ;

     void Binarize( tPlane8& source, uint8_t thre, uint8_t color ) ;
     void Binarize( tImgPlanar& source, uint8_t thre, uint8_t color ) ;

     // zoom
     void ZoomIn( tImgPlanar const& source, tImgPlanar& target, int scale ) ;
     void ZoomOut( tImgPlanar const& source, tImgPlanar& target, int scale ) ;
     void Zoom( tImgPlanar const& source, tImgPlanar& target, double scale );
     void ZoomToSize( tImgPlanar const& source, tImgPlanar& target,  Dword sizex, Dword sizey ) ;
     void zoom( tImgPlanar const& source, tImgPlanar &target, double xscale, double yscale );
     
test in progress,
    ZoomIn works
    ZoomOut works
    Sobel works
    Binarize works
    all in rimg_graph are working
    Scale works
    Multiplicate works 
    Gauss3 works
    all in helper are working
    all in testimages are working
    ExtractAoi works
    all image read/write is working
    Blob analysis is working, see main.cpp
        tBlobs bl;
        bl.threshold() = 25;
        bl.extract( img );
        bl.background() = 25;
        bl.min_area() = 50;
        bl.calculateMidpnt();
        bl.calculateSize();
        bl.calculateIntegral();
        bl.calculateArea();