Writing and Reading Multi-Page Files (Delphi 4)

Take the following steps to create a Multi-Page file, then load and display the images from the file. Only TIFF (MPT) and PCX (DCX) formats support Multi-Page files.

procedure TForm1.Button1Click(Sender: TObject);
var
   RasterIO1: LEADRasterIO;
   RasterIO2: LEADRasterIO;
     HeightFactor1, WidthFactor1,
   HeightFactor2, WidthFactor2,
     HeightAllowed, WidthAllowed: Integer;
     ImageWidth1, ImageHeight1: Integer;
     ImageWidth2, ImageHeight2: integer;
   Ret: Smallint;
begin

   RasterIO1:= CreateComObject(CLASS_LEADRasterIO) as LEADRasterIO;
     RasterIO2:= CreateComObject(CLASS_LEADRasterIO) as LEADRasterIO;

     //Disable automatic repainting of the image.
     LEADRasterView1.AutoRepaint := False;
     LEADRasterView2.AutoRepaint := False;
     //Turn off scroll bars to make sure we use the full client area.
     LEADRasterView1.AutoScroll := False;
     LEADRasterView2.AutoScroll := False;
     //Position and size the main form so that it takes up most of the screen.
     Width := Trunc(Screen.Width * 0.9) ;
     Height:= Trunc(Screen.Height* 0.8) ;
     Left := Trunc ((Screen.Width- Width) / 2);
     Top := Trunc ((Screen.Height- Height)/ 2);
     //Display the form and set the mouse pointer to an hourglass.

     Screen.Cursor := crhourGlass;
     //Load the bitmaps. These hard-coded path names may be different on your system.
     RasterIO1.Load ( LEADRasterView1.Raster, WideString('v:\images\image1.cmp'), 0, 0, 1 ) ;
     RasterIO2.Load ( LEADRasterView2.Raster, WideString('v:\images\image2.cmp'), 0, 0, 1 ) ;

     //Save the bitmaps to a single multipage TIFF file
     RasterIO1.Save ( LEADRasterView1.Raster, WideString('v:\images\combined.mpt'), FILE_TIF, 24, 0, SAVE_OVERWRITE ) ;
     RasterIO2.Save ( LEADRasterView2.Raster, WideString('v:\images\combined.mpt'), FILE_TIF, 24, 0, SAVE_APPEND );
     //Get information about the images so that we can size the controls.
     RasterIO1.GetFileInfo ( LEADRasterView1.Raster, WideString('v:\images\combined.mpt'), 1, 0 ) ;
     RasterIO2.GetFileInfo ( LEADRasterView2.Raster, WideString('v:\images\combined.mpt'), 2, 0 );
     //Clear the bitmaps from memory
     LEADRasterView1.Raster.Bitmap := 0;
     LEADRasterView2.Raster.Bitmap := 0;
     //Make the controls visible so that we can size and position them.
     //They will not really appear until we load an image and paint it.
     LEADRasterView1.Visible := True;
     LEADRasterView2.Visible := True;
     //Set the variables used for preserving the aspect ratio.
     HeightFactor1 := Trunc (RasterIO1.InfoHeight);
     WidthFactor1 := Trunc (RasterIO1.InfoWidth);
     HeightFactor2 := Trunc (RasterIO2.InfoHeight);
     WidthFactor2 := Trunc (RasterIO2.InfoWidth);
     HeightAllowed := Trunc (Height * 0.8);
     WidthAllowed := Trunc (Width * 0.45);
     //Center each LEAD control on half of the form, preserving the aspect ratio.
     //Check to see if using the maximum width will make the image too tall.
     //Set the dimensions based on the result.
     if (WidthAllowed * HeightFactor1) / WidthFactor1 < HeightAllowed then
     begin
      LEADRasterView1.Left := Trunc ((Width / 4) - (WidthAllowed / 2));
       LEADRasterView1.Width := WidthAllowed;
       LEADRasterView1.Height := Trunc ((LEADRasterView1.Width * HeightFactor1) / WidthFactor1);
       LEADRasterView1.Top := Trunc ((Height - LEADRasterView1.Height) / 2);
     end
     else
     begin
      LEADRasterView1.Top := Trunc ((Height - HeightAllowed) / 2);
       LEADRasterView1.Height := HeightAllowed;
       LEADRasterView1.Width := Trunc ((LEADRasterView1.Height * WidthFactor1) / HeightFactor1);
       LEADRasterView1.Left := Trunc ((Width / 4) - (LEADRasterView1.Width / 2));
     end;
     if (WidthAllowed * HeightFactor2) / WidthFactor2 < HeightAllowed then
     begin
      LEADRasterView2.Left := Trunc ((Width * 3 / 4) - (WidthAllowed / 2));
       LEADRasterView2.Width := WidthAllowed;
       LEADRasterView2.Height := Trunc ((LEADRasterView2.Width * HeightFactor2) / WidthFactor2);
       LEADRasterView2.Top := Trunc ((Height - LEADRasterView2.Height) / 2);
     end
     else
     begin
      LEADRasterView2.Top := Trunc ((Height - HeightAllowed) / 2);
       LEADRasterView2.Height := HeightAllowed;
       LEADRasterView2.Width := Trunc ((LEADRasterView2.Height * WidthFactor2) / HeightFactor2);
       LEADRasterView2.Left := Trunc ((Width * 3 / 4) - (LEADRasterView2.Width / 2));
     end;
     //Load the bitmaps from the multipage TIFF file
     RasterIO1.Load ( LEADRasterView1.Raster, 'v:\images\combined.mpt', 24, 1, 1);
     RasterIO2.Load ( LEADRasterView2.Raster, 'v:\images\combined.mpt', 24, 2, 1);
     //Set the image display sizes to match the LEAD controls
     ImageWidth1 := Trunc (LEADRasterView1.ScaleWidth);
     ImageHeight1 := Trunc (LEADRasterView1.ScaleHeight);
     LEADRasterView1.SetDstRect ( 0, 0, ImageWidth1, ImageHeight1, Ret ) ;
     LEADRasterView1.SetDstClipRect ( 0, 0, ImageWidth1, ImageHeight1, Ret ) ;
     //Set the image display sizes to match the LEAD controls
     ImageWidth2 := Trunc (LEADRasterView2.ScaleWidth);
     ImageHeight2 := Trunc (LEADRasterView2.ScaleHeight);
     LEADRasterView2.SetDstRect ( 0, 0, ImageWidth2, ImageHeight2, Ret ) ;
     LEADRasterView2.SetDstClipRect (0, 0, ImageWidth2, ImageHeight2, Ret ) ;

     //Display the images
     LEADRasterView1.ForceRepaint (Ret) ;
     LEADRasterView2.ForceRepaint(Ret) ;
     //Set the mouse pointer back to the default
     Screen.Cursor:= crDefault;
end;

Uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, ComObj, LTRASTERIOLib_TLB;