This example will load a PDF document using different rasterize document options and show its effect on the result raster image width, height and resolution.

Visual Basic

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Public Sub RasterizeDocumentExample()    ' Unlock support for loading raster PDF files    RasterSupport.Unlock(RasterSupportType.PdfRead, "Your key here")    ' Initialize the RasterCodecs object to use    RasterCodecs.Startup()    Dim codecs As New RasterCodecs()    ' Enable using the RasterizeDocumentOptions    Dim rasterizeDocumentLoadOptions As CodecsRasterizeDocumentLoadOptions = codecs.Options.RasterizeDocument.Load    rasterizeDocumentLoadOptions.Enabled = True    ' No margins (only used with RTF and TXT files)    rasterizeDocumentLoadOptions.LeftMargin = 0    rasterizeDocumentLoadOptions.TopMargin = 0    rasterizeDocumentLoadOptions.RightMargin = 0    rasterizeDocumentLoadOptions.BottomMargin = 0    ' The PDF file we are testing. This could be an XPS, RTF, TXT or XLS file as well    Dim imageFileName As String = "C:\Users\Public\Documents\LEADTOOLS Images\Leadtools.pdf"    ' Show the file information    Using imageInfo As CodecsImageInfo = codecs.GetInformation(imageFileName, True)       Dim documentImageInfo As CodecsDocumentImageInfo = imageInfo.Document       ' If this is a document file, show the document information       If documentImageInfo.IsDocumentFile Then          Console.WriteLine("Document file")          Console.WriteLine(" Original size is: {0} by {1} {2}", _             documentImageInfo.PageWidth, documentImageInfo.PageHeight, documentImageInfo.Unit)          Console.WriteLine(" Using current rasterization, load size will be: {0} by {1} pixels at {2} by {3}", _             imageInfo.Width, imageInfo.Height, imageInfo.XResolution, imageInfo.YResolution)       Else          ' Regular raster image, show the image information          Console.WriteLine("Raster file")          Console.WriteLine(" Original size is: {0} by {1} pixels at {2} by {3}", _             imageInfo.Width, imageInfo.Height, imageInfo.XResolution, imageInfo.YResolution)       End If    End Using    ' Example 1. Load at original document size at 300 DPI    rasterizeDocumentLoadOptions.SizeMode = CodecsRasterizeDocumentSizeMode.None    rasterizeDocumentLoadOptions.XResolution = 300    rasterizeDocumentLoadOptions.YResolution = 300    Using image As RasterImage = codecs.Load(imageFileName, 0, CodecsLoadByteOrder.BgrOrGray, 1, 1)       ShowResult(codecs, image)    End Using    ' Example 2. Fit the document at 640 by 480 pixels at 96 DPI keeping the aspect ratio    rasterizeDocumentLoadOptions.SizeMode = CodecsRasterizeDocumentSizeMode.Fit    rasterizeDocumentLoadOptions.PageWidth = 640    rasterizeDocumentLoadOptions.PageHeight = 480    rasterizeDocumentLoadOptions.Unit = CodecsRasterizeDocumentUnit.Pixel    rasterizeDocumentLoadOptions.XResolution = 96    rasterizeDocumentLoadOptions.YResolution = 96    Using image As RasterImage = codecs.Load(imageFileName, 0, CodecsLoadByteOrder.BgrOrGray, 1, 1)       ShowResult(codecs, image)    End Using    ' Example 3. Fit the document at 8.5 by 11 inches at 96 DPI keeping the aspect ratio    rasterizeDocumentLoadOptions.SizeMode = CodecsRasterizeDocumentSizeMode.Fit    rasterizeDocumentLoadOptions.PageWidth = 8.5    rasterizeDocumentLoadOptions.PageHeight = 11    rasterizeDocumentLoadOptions.Unit = CodecsRasterizeDocumentUnit.Inch    rasterizeDocumentLoadOptions.XResolution = 300    rasterizeDocumentLoadOptions.YResolution = 300    Using image As RasterImage = codecs.Load(imageFileName, 0, CodecsLoadByteOrder.BgrOrGray, 1, 1)       ShowResult(codecs, image)    End Using    ' Example 4. Stretch the image to always be 4 by 4 inches at 150 DPI. Aspect ratio may differ    rasterizeDocumentLoadOptions.SizeMode = CodecsRasterizeDocumentSizeMode.Stretch    rasterizeDocumentLoadOptions.PageWidth = 4    rasterizeDocumentLoadOptions.PageHeight = 4    rasterizeDocumentLoadOptions.Unit = CodecsRasterizeDocumentUnit.Inch    rasterizeDocumentLoadOptions.XResolution = 150    rasterizeDocumentLoadOptions.YResolution = 150    Using image As RasterImage = codecs.Load(imageFileName, 0, CodecsLoadByteOrder.BgrOrGray, 1, 1)       ShowResult(codecs, image)    End Using    codecs.Dispose()    RasterCodecs.Shutdown() End Sub Private Shared Sub ShowResult(ByVal codecs As RasterCodecs, ByVal image As RasterImage)    Dim rasterizeDocumentLoadOptions As CodecsRasterizeDocumentLoadOptions = codecs.Options.RasterizeDocument.Load    Console.WriteLine("Showing result..")    Console.WriteLine(" Current rasterization options:")    Console.WriteLine(" Size mode is: {0}", rasterizeDocumentLoadOptions.SizeMode)    Console.WriteLine(" Page size is {0} by {1} {2}", _       rasterizeDocumentLoadOptions.PageWidth, rasterizeDocumentLoadOptions.PageHeight, rasterizeDocumentLoadOptions.Unit)    Console.WriteLine(" Resolution is {0} by {1}", _       rasterizeDocumentLoadOptions.XResolution, rasterizeDocumentLoadOptions.YResolution)    Console.WriteLine(" Loaded raster image size is: {0} by {1} at {2} by {3}", _       image.ImageWidth, image.ImageHeight, image.XResolution, image.YResolution)    ' Code to verify our results    ' Get the suggested page width and height in pixels    Dim pageWidthInPixels As Double    Dim pageHeightInPixels As Double    Select Case rasterizeDocumentLoadOptions.Unit       Case CodecsRasterizeDocumentUnit.Inch          pageWidthInPixels = rasterizeDocumentLoadOptions.PageWidth * rasterizeDocumentLoadOptions.XResolution          pageHeightInPixels = rasterizeDocumentLoadOptions.PageHeight * rasterizeDocumentLoadOptions.YResolution       Case CodecsRasterizeDocumentUnit.Millimeter          pageWidthInPixels = rasterizeDocumentLoadOptions.PageWidth * rasterizeDocumentLoadOptions.XResolution * 25.400000025908          pageHeightInPixels = rasterizeDocumentLoadOptions.PageHeight * rasterizeDocumentLoadOptions.YResolution * 25.400000025908       Case CodecsRasterizeDocumentUnit.Pixel          pageWidthInPixels = rasterizeDocumentLoadOptions.PageWidth          pageHeightInPixels = rasterizeDocumentLoadOptions.PageHeight    End Select    ' Verify    Select Case rasterizeDocumentLoadOptions.SizeMode       Case CodecsRasterizeDocumentSizeMode.Fit, CodecsRasterizeDocumentSizeMode.FitAlways          ' The image width/height must not be greater than suggested page width/height          Console.WriteLine("Image width/height must be less than or equal to page width/height")          System.Diagnostics.Debug.Assert(image.ImageWidth <= pageWidthInPixels)          System.Diagnostics.Debug.Assert(image.ImageHeight <= pageHeightInPixels)       Case CodecsRasterizeDocumentSizeMode.FitWidth          ' The image width must be equal to the suggested page width          Console.WriteLine("Image width must be equal to page width")          System.Diagnostics.Debug.Assert(image.ImageWidth = pageWidthInPixels)       Case CodecsRasterizeDocumentSizeMode.Stretch          ' The image width/height must be equal to the suggested page width/height          Console.WriteLine("Image width/height must be equal to suggested page width/height")          System.Diagnostics.Debug.Assert(image.ImageWidth = pageWidthInPixels)          System.Diagnostics.Debug.Assert(image.ImageHeight = pageHeightInPixels)       Case CodecsRasterizeDocumentSizeMode.None          Console.WriteLine("Loading at original document page size")          ' No checking    End Select End Sub

C#

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public void RasterizeDocumentExample()  {     // Unlock support for loading raster PDF files     RasterSupport.Unlock(RasterSupportType.PdfRead, "Your key here");     // Initialize the RasterCodecs object to use     RasterCodecs.Startup();     RasterCodecs codecs = new RasterCodecs();       // Enable using the RasterizeDocumentOptions     CodecsRasterizeDocumentLoadOptions rasterizeDocumentLoadOptions = codecs.Options.RasterizeDocument.Load;     rasterizeDocumentLoadOptions.Enabled = true;       // No margins (only used with RTF and TXT files)     rasterizeDocumentLoadOptions.LeftMargin = 0;     rasterizeDocumentLoadOptions.TopMargin = 0;     rasterizeDocumentLoadOptions.RightMargin = 0;     rasterizeDocumentLoadOptions.BottomMargin = 0;       // The PDF file we are testing. This could be an XPS, RTF, TXT or XLS file as well     string imageFileName = @"C:\Users\Public\Documents\LEADTOOLS Images\Leadtools.pdf";       // Show the file information     using(CodecsImageInfo imageInfo = codecs.GetInformation(imageFileName, true))     {        CodecsDocumentImageInfo documentImageInfo = imageInfo.Document;          // If this is a document file, show the document information        if(documentImageInfo.IsDocumentFile)        {           Console.WriteLine("Document file");           Console.WriteLine("  Original size is: {0} by {1} {2}",              documentImageInfo.PageWidth, documentImageInfo.PageHeight, documentImageInfo.Unit);             Console.WriteLine("  Using current rasterization, load size will be: {0} by {1} pixels at {2} by {3}",              imageInfo.Width, imageInfo.Height, imageInfo.XResolution, imageInfo.YResolution);        }        else        {           // Regular raster image, show the image information           Console.WriteLine("Raster file");           Console.WriteLine("  Original size is: {0} by {1} pixels at {2} by {3}",              imageInfo.Width, imageInfo.Height, imageInfo.XResolution, imageInfo.YResolution);        }     }       // Example 1. Load at original document size at 300 DPI     rasterizeDocumentLoadOptions.SizeMode = CodecsRasterizeDocumentSizeMode.None;     rasterizeDocumentLoadOptions.XResolution = 300;     rasterizeDocumentLoadOptions.YResolution = 300;       using(RasterImage image = codecs.Load(imageFileName, 0, CodecsLoadByteOrder.BgrOrGray, 1, 1))     {        ShowResult(codecs, image);     }       // Example 2. Fit the document at 640 by 480 pixels at 96 DPI keeping the aspect ratio     rasterizeDocumentLoadOptions.SizeMode = CodecsRasterizeDocumentSizeMode.Fit;     rasterizeDocumentLoadOptions.PageWidth = 640;     rasterizeDocumentLoadOptions.PageHeight = 480;     rasterizeDocumentLoadOptions.Unit = CodecsRasterizeDocumentUnit.Pixel;     rasterizeDocumentLoadOptions.XResolution = 96;     rasterizeDocumentLoadOptions.YResolution = 96;       using(RasterImage image = codecs.Load(imageFileName, 0, CodecsLoadByteOrder.BgrOrGray, 1, 1))     {        ShowResult(codecs, image);     }       // Example 3. Fit the document at 8.5 by 11 inches at 96 DPI keeping the aspect ratio     rasterizeDocumentLoadOptions.SizeMode = CodecsRasterizeDocumentSizeMode.Fit;     rasterizeDocumentLoadOptions.PageWidth = 8.5;     rasterizeDocumentLoadOptions.PageHeight = 11;     rasterizeDocumentLoadOptions.Unit = CodecsRasterizeDocumentUnit.Inch;     rasterizeDocumentLoadOptions.XResolution = 300;     rasterizeDocumentLoadOptions.YResolution = 300;       using(RasterImage image = codecs.Load(imageFileName, 0, CodecsLoadByteOrder.BgrOrGray, 1, 1))     {        ShowResult(codecs, image);     }       // Example 4. Stretch the image to always be 4 by 4 inches at 150 DPI. Aspect ratio may differ     rasterizeDocumentLoadOptions.SizeMode = CodecsRasterizeDocumentSizeMode.Stretch;     rasterizeDocumentLoadOptions.PageWidth = 4;     rasterizeDocumentLoadOptions.PageHeight = 4;     rasterizeDocumentLoadOptions.Unit = CodecsRasterizeDocumentUnit.Inch;     rasterizeDocumentLoadOptions.XResolution = 150;     rasterizeDocumentLoadOptions.YResolution = 150;       using(RasterImage image = codecs.Load(imageFileName, 0, CodecsLoadByteOrder.BgrOrGray, 1, 1))     {        ShowResult(codecs, image);     }       codecs.Dispose();     RasterCodecs.Shutdown();  }    private static void ShowResult(RasterCodecs codecs, RasterImage image)  {     CodecsRasterizeDocumentLoadOptions rasterizeDocumentLoadOptions = codecs.Options.RasterizeDocument.Load;       Console.WriteLine("Showing result..");     Console.WriteLine("  Current rasterization options:");     Console.WriteLine("    Size mode is: {0}", rasterizeDocumentLoadOptions.SizeMode);     Console.WriteLine("    Page size is {0} by {1} {2}",        rasterizeDocumentLoadOptions.PageWidth, rasterizeDocumentLoadOptions.PageHeight, rasterizeDocumentLoadOptions.Unit);     Console.WriteLine("    Resolution is {0} by {1}",        rasterizeDocumentLoadOptions.XResolution, rasterizeDocumentLoadOptions.YResolution);       Console.WriteLine("  Loaded raster image size is: {0} by {1} at {2} by {3}",        image.ImageWidth, image.ImageHeight, image.XResolution, image.YResolution);       // Code to verify our results       // Get the suggested page width and height in pixels     double pageWidthInPixels;     double pageHeightInPixels;       switch(rasterizeDocumentLoadOptions.Unit)     {        case CodecsRasterizeDocumentUnit.Inch:           pageWidthInPixels = rasterizeDocumentLoadOptions.PageWidth * rasterizeDocumentLoadOptions.XResolution;           pageHeightInPixels = rasterizeDocumentLoadOptions.PageHeight * rasterizeDocumentLoadOptions.YResolution;           break;          case CodecsRasterizeDocumentUnit.Millimeter:           pageWidthInPixels = rasterizeDocumentLoadOptions.PageWidth * rasterizeDocumentLoadOptions.XResolution * 25.400000025908000026426160026955;           pageHeightInPixels = rasterizeDocumentLoadOptions.PageHeight * rasterizeDocumentLoadOptions.YResolution * 25.400000025908000026426160026955;           break;          case CodecsRasterizeDocumentUnit.Pixel:        default:           pageWidthInPixels = rasterizeDocumentLoadOptions.PageWidth;           pageHeightInPixels = rasterizeDocumentLoadOptions.PageHeight;           break;     }       // Verify     switch(rasterizeDocumentLoadOptions.SizeMode)     {        case CodecsRasterizeDocumentSizeMode.Fit:        case CodecsRasterizeDocumentSizeMode.FitAlways:           // The image width/height must not be greater than suggested page width/height           Console.WriteLine("Image width/height must be less than or equal to page width/height");           System.Diagnostics.Debug.Assert(image.ImageWidth <= pageWidthInPixels);           System.Diagnostics.Debug.Assert(image.ImageHeight <= pageHeightInPixels);           break;          case CodecsRasterizeDocumentSizeMode.FitWidth:           // The image width must be equal to the suggested page width           Console.WriteLine("Image width must be equal to page width");           System.Diagnostics.Debug.Assert(image.ImageWidth == pageWidthInPixels);           break;          case CodecsRasterizeDocumentSizeMode.Stretch:           // The image width/height must be equal to the suggested page width/height           Console.WriteLine("Image width/height must be equal to suggested page width/height");           System.Diagnostics.Debug.Assert(image.ImageWidth == pageWidthInPixels);           System.Diagnostics.Debug.Assert(image.ImageHeight == pageHeightInPixels);           break;          case CodecsRasterizeDocumentSizeMode.None:        default:           Console.WriteLine("Loading at original document page size");           // No checking           break;     }  }

LEADTOOLS provides support for loading a document as a raster image. Documents formats such as PDF, XPS, XLS, RTF and Text do not contain physical width, height or resolution. It is up to the loader (in this case, the RasterCodecs object) to specify the transformation from logical coordinates to physical pixels through a process called rasterization.

Rasterization is the process of converting a document to a raster image. To check if a certain file on disk (or in a .NET stream) contains a document file rather than a regular raster image, call the RasterCodecs.GetInformation and check the CodecsDocumentImageInfo.IsDocumentFile property. Here is a code snippet:

             CodecsImageInfo imageInfo = rasterCodecsInstance.GetInformation(fileName, true);
             if(imageInfo.Document.IsDocumentFile)
             {
                // A document file (PDF, XPS, rtc), show the original document size:
                Console.WriteLine("Document file, original size is {0} by {1} {2}",
                   imageInfo.Document.PageWidth, imageInfo.Document.PageHeight, imageInfo.Document.Unit);
            
                // Your code specific to rasterization based on the original document size goes here
             }
             

To rasterize a document file, set the properties of the CodecsRasterizeDocumentLoadOptions to the required value. For example, the following code snippet will instruct LEADTOOLS to fit any document files into 8.5 by 11 inches at 300 paper size. Every document file loaded with the RasterCodecs.Load methods will have width/height of no more than 2550 by 3300 pixels with a resolution of 300 by 300:

             CodecsRasterizeDocumentLoadOptions rasterDocumentLoadOptions = rasterCodecsInstance.Options.RasterizeDocument.Load;
             // Enable rasterization
             rasterDocumentLoadOptions.Enabled = true;
             // Set the size mode, we want to fit
             rasterDocumentLoadOptions.SizeMode = CodecsRasterizeDocumentSizeMode.Fit;
             // Set the page size
             rasterDocumentLoadOptions.PageWidth = 8.5;
             rasterDocumentLoadOptions.PageHeight = 11;
             rasterDocumentLoadOptions.Unit = CodecsRasterizeDocumentUnit.Inch;
             // And the resolution
             rasterDocumentLoadOptions.XResolution = 300;
             rasterDocumentLoadOptions.YResolution = 300;
            
             // Load the image
             RasterImage image = rasterCodecsInstance.Load(fileName);
            
             // Show its pixel size, it should be less than or equal to
             // 2550 by 3300 pixels (8.5 * 300 by 11 * 300)
             Console.WriteLine("Loaded image size: {0} by {1} pixels at {2} by {3}",
             image.ImageWidth, image.ImageHeight, image.XResolution, image.YResolution);
             

The CodecsRasterizeDocumentLoadOptions class contains the following properties:

The value of CodecsRasterizeDocumentLoadOptions.Enabled:P:Leadtools.Codecs.CodecsRasterizeDocumentLoadOptions.Enabled This is done for backward compatibilty and means the current T:Leadtools.Codecs.CodecsRasterizeDocumentLoadOptions A convenient way to do that is after instantiating the T:Leadtools.Codecs.RasterCodecs object you will be using in your codeCodecsRasterizeDocumentLoadOptions.Enabled:P:Leadtools.Codecs.CodecsRasterizeDocumentLoadOptions.Enabled% to true in the next version so it is recommended you start porting your code to use the new options.

System.Object
   Leadtools.Codecs.CodecsRasterizeDocumentLoadOptions

Target Platforms: Microsoft .NET Framework 3.0, Windows XP, Windows Server 2003 family, Windows Server 2008 family

Reference