FUNCTION FlipReverseScanLine(CONST Flip, Reverse:  BOOLEAN;
                               CONST Bitmap:  TBitmap):  TBitmap;
  VAR
    i     :  INTEGER;
    j     :  INTEGER;
    RowIn :  pRGBArray;
    RowOut:  pRGBArray;
  BEGIN
    IF   Bitmap.PixelFormat <> pf24bit
    THEN RAISE EBitmapError.Create('Can Flip/Reverse only 24-bit bitmap');
 
    RESULT := TBitmap.Create;
    RESULT.Width       := Bitmap.Width;
    RESULT.Height      := Bitmap.Height;
    RESULT.PixelFormat := Bitmap.PixelFormat;
 
    FOR j := 0 TO Bitmap.Height-1 DO
    BEGIN
      RowIn := Bitmap.Scanline[j];
      IF   Flip
      THEN RowOut := RESULT.Scanline[Bitmap.Height - 1 - j]
      ELSE RowOut := RESULT.Scanline[j];
 
      // Optimization technique:  Use two FOR loops so IF is outside of inner loop
      IF   Reverse
      THEN BEGIN
        FOR i := 0 TO Bitmap.Width-1 DO
          RowOut[i] := RowIn[Bitmap.Width-1-i]
      END
      ELSE BEGIN
        FOR i := 0 TO Bitmap.Width-1 DO
          RowOut[i] := RowIn[i]
      END
 
    END
  END {FlipReverseScanLine};

for(int j=0; j < (ImgHeight-1);j++)
	{
	rowIn = (S_PixelColours*)OrigImg->ScanLine[j];
        rowOut = (S_PixelColours*)result->ScanLine[j];
	for(int i=0; i<(ImgWidth-1);i++)
	{
        rowOut[i] = rowIn[ImgWidth-1-j];
	}