LEADTOOLS Image File Support (Leadtools.Codecs assembly)
LEAD Technologies, Inc

ReadComment(String,Int32,RasterCommentMetadataType) Method

Example 





Leadtools.Codecs Namespace > RasterCodecs Class > ReadComment Method : ReadComment(String,Int32,RasterCommentMetadataType) Method
A System.String containing the input file name.
1-based index of the page from which to read the comment.
The type of comment. Refer to Types of File Comments.
Gets a comment field from a file. .NET support Silverlight support
Syntax
'Declaration
 
Public Overloads Function ReadComment( _
   ByVal fileName As String, _
   ByVal pageNumber As Integer, _
   ByVal type As RasterCommentMetadataType _
) As RasterCommentMetadata
'Usage
 
Dim instance As RasterCodecs
Dim fileName As String
Dim pageNumber As Integer
Dim type As RasterCommentMetadataType
Dim value As RasterCommentMetadata
 
value = instance.ReadComment(fileName, pageNumber, type)
 function Leadtools.Codecs.RasterCodecs.ReadComment(String,Int32,RasterCommentMetadataType)( 
   fileName ,
   pageNumber ,
   type 
)

Parameters

fileName
A System.String containing the input file name.
pageNumber
1-based index of the page from which to read the comment.
type
The type of comment. Refer to Types of File Comments.

Return Value

A Leadtools.RasterCommentMetadata object containing the comment field information. If no such comment is found in the file, this method will return a null reference (Nothing in Visual Basic).
Remarks

Some file formats can contain comments, and some cannot, and each file format has its own set of comment types. When you save a file, the comments in the Leadtools.RasterImage object can be saved in the file. The index into the array (specified using a constant) determines the type of comment.

You can use CommentsSupported to determine whether a certain file format supports tags.

To read all the comments stored in a file, use ReadComments(String,Int32).

Example
  
Public Sub CommentsExample()
      Dim codecs As RasterCodecs = New RasterCodecs()

      Dim srcFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp")
      Dim destFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Image1_Comments.tif")

      ' Convert the source file to TIF
      Console.WriteLine("Converting the source file to TIF")
      codecs.Convert(srcFileName, destFileName, RasterImageFormat.Tif, 0, 0, 24, Nothing)

      ' Add the artist comment
      Dim writeComment As RasterCommentMetadata = New RasterCommentMetadata()
      writeComment.Type = RasterCommentMetadataType.Artist
      writeComment.FromAscii("LEADTOOLS")

      Console.WriteLine("Writing the following comment:")
      Console.WriteLine(" Type:{0}, Data:{1}", writeComment.Type, writeComment.ToAscii())

      codecs.WriteComment(destFileName, 1, writeComment)

      ' Read the comment back
      Dim readComment As RasterCommentMetadata = codecs.ReadComment(destFileName, 1, RasterCommentMetadataType.Artist)
      Console.WriteLine("The following comment has been read:")
      Console.WriteLine(" Type:{0}, Data:{1}", readComment.Type, readComment.ToAscii())

      ' Write a few comments to the file in one pass
      Dim comments As RasterCollection(Of RasterCommentMetadata) = New RasterCollection(Of RasterCommentMetadata)()
      writeComment = New RasterCommentMetadata()
      writeComment.Type = RasterCommentMetadataType.Artist
      writeComment.FromAscii("LEADTOOLS Again")
      comments.Add(writeComment)

      writeComment = New RasterCommentMetadata()
      writeComment.Type = RasterCommentMetadataType.Copyright
      writeComment.FromAscii("(c) 2006")
      comments.Add(writeComment)

      Console.WriteLine("Writing the following comments to the file:")
      For Each comment As RasterCommentMetadata In comments
         Console.WriteLine(" Type:{0}, Data:{1}", comment.Type, comment.ToAscii())
      Next comment

      codecs.WriteComments(destFileName, 1, comments)

      ' Now get all the comments in the file and show them:
      Console.WriteLine("Reading all comments from the file:")

      Dim tifComments As RasterCommentMetadataType() = _
      { _
         RasterCommentMetadataType.Artist, _
         RasterCommentMetadataType.Copyright, _
         RasterCommentMetadataType.DateTime, _
         RasterCommentMetadataType.Description, _
         RasterCommentMetadataType.HostComputer, _
         RasterCommentMetadataType.Make, _
         RasterCommentMetadataType.Model, _
         RasterCommentMetadataType.NameOfDocument, _
         RasterCommentMetadataType.NameOfPage, _
         RasterCommentMetadataType.Software _
      }

      For Each tifComment As RasterCommentMetadataType In tifComments
         Dim comment As RasterCommentMetadata = codecs.ReadComment(destFileName, 1, tifComment)
         If Not comment Is Nothing Then
            Console.Write("Found comment, Type:{0}, Data:", comment.Type)

            Dim dataType As RasterCommentMetadataDataType = RasterCommentMetadata.GetDataType(comment.Type)

            Dim byteData As Byte()
            Dim shortData As Short()
            Dim rationalData As RasterMetadataRational()
            Dim urationalData As RasterMetadataURational()

            Select Case dataType
               Case RasterCommentMetadataDataType.Ascii
                  Console.WriteLine(comment.ToAscii())

               Case RasterCommentMetadataDataType.Byte
                  byteData = comment.ToByte()
                  Dim i As Integer = 0
                  Do While i < byteData.Length
                     Console.Write("{0:X} ", byteData(i))
                     i += 1
                  Loop
                  Console.WriteLine()

               Case RasterCommentMetadataDataType.Int16
                  shortData = comment.ToInt16()
                  Dim i As Integer = 0
                  Do While i < shortData.Length
                     Console.Write("{0:X} ", shortData(i))
                     i += 1
                  Loop
                  Console.WriteLine()

               Case RasterCommentMetadataDataType.Rational
                  rationalData = comment.ToRational()
                  Dim i As Integer = 0
                  Do While i < rationalData.Length
                     Console.Write("{0}/{1) ", rationalData(i).Numerator, rationalData(i).Denominator)
                     i += 1
                  Loop
                  Console.WriteLine()

               Case RasterCommentMetadataDataType.URational
                  urationalData = comment.ToURational()
                  Dim i As Integer = 0
                  Do While i < urationalData.Length
                     Console.Write("{0}/{1) ", urationalData(i).Numerator, urationalData(i).Denominator)
                     i += 1
                  Loop
                  Console.WriteLine()
            End Select
         End If
      Next tifComment

      ' Clean up
      codecs.Dispose()
   End Sub

Public NotInheritable Class LEAD_VARS
   Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images"
End Class
public void CommentsExample()
     {
         RasterCodecs codecs = new RasterCodecs();

         string srcFileName = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp");
         string destFileName = Path.Combine(LEAD_VARS.ImagesDir, "Image1_Comments.tif");

         // Convert the source file to TIF
         Console.WriteLine("Converting the source file to TIF");
         codecs.Convert(srcFileName, destFileName, RasterImageFormat.Tif, 0, 0, 24, null);

         // Add the artist comment
         RasterCommentMetadata writeComment = new RasterCommentMetadata();
         writeComment.Type = RasterCommentMetadataType.Artist;
         writeComment.FromAscii("LEADTOOLS");

         Console.WriteLine("Writing the following comment:");
         Console.WriteLine(" Type:{0}, Data:{1}", writeComment.Type, writeComment.ToAscii());

         codecs.WriteComment(destFileName, 1, writeComment);

         // Read the comment back
         RasterCommentMetadata readComment = codecs.ReadComment(destFileName, 1, RasterCommentMetadataType.Artist);
         Console.WriteLine("The following comment has been read:");
         Console.WriteLine(" Type:{0}, Data:{1}", readComment.Type, readComment.ToAscii());

         // Write a few comments to the file in one pass
         RasterCollection<RasterCommentMetadata> comments = new RasterCollection<RasterCommentMetadata>();
         writeComment = new RasterCommentMetadata();
         writeComment.Type = RasterCommentMetadataType.Artist;
         writeComment.FromAscii("LEADTOOLS Again");
         comments.Add(writeComment);

         writeComment = new RasterCommentMetadata();
         writeComment.Type = RasterCommentMetadataType.Copyright;
         writeComment.FromAscii("(c) 2006");
         comments.Add(writeComment);

         Console.WriteLine("Writing the following comments to the file:");
         foreach (RasterCommentMetadata comment in comments)
             Console.WriteLine(" Type:{0}, Data:{1}", comment.Type, comment.ToAscii());

         codecs.WriteComments(destFileName, 1, comments);

         // Now get all the comments in the file and show them:
         Console.WriteLine("Reading all comments from the file:");

         RasterCommentMetadataType[] tifComments =
      {
         RasterCommentMetadataType.Artist,
         RasterCommentMetadataType.Copyright,
         RasterCommentMetadataType.DateTime,
         RasterCommentMetadataType.Description,
         RasterCommentMetadataType.HostComputer,
         RasterCommentMetadataType.Make,
         RasterCommentMetadataType.Model,
         RasterCommentMetadataType.NameOfDocument,
         RasterCommentMetadataType.NameOfPage,
         RasterCommentMetadataType.Software,
      };

         foreach (RasterCommentMetadataType tifComment in tifComments)
         {
             RasterCommentMetadata comment = codecs.ReadComment(destFileName, 1, tifComment);
             if (comment != null)
             {
                 Console.Write("Found comment, Type:{0}, Data:", comment.Type);

                 RasterCommentMetadataDataType dataType = RasterCommentMetadata.GetDataType(comment.Type);

                 byte[] byteData;
                 short[] shortData;
                 RasterMetadataRational[] rationalData;
                 RasterMetadataURational[] urationalData;

                 switch (dataType)
                 {
                     case RasterCommentMetadataDataType.Ascii:
                         Console.WriteLine(comment.ToAscii());
                         break;

                     case RasterCommentMetadataDataType.Byte:
                         byteData = comment.ToByte();
                         for (int i = 0; i < byteData.Length; i++)
                             Console.Write("{0:X} ", byteData[i]);
                         Console.WriteLine();
                         break;

                     case RasterCommentMetadataDataType.Int16:
                         shortData = comment.ToInt16();
                         for (int i = 0; i < shortData.Length; i++)
                             Console.Write("{0:X} ", shortData[i]);
                         Console.WriteLine();
                         break;

                     case RasterCommentMetadataDataType.Rational:
                         rationalData = comment.ToRational();
                         for (int i = 0; i < rationalData.Length; i++)
                             Console.Write(@"{0}/{1) ", rationalData[i].Numerator, rationalData[i].Denominator);
                         Console.WriteLine();
                         break;

                     case RasterCommentMetadataDataType.URational:
                         urationalData = comment.ToURational();
                         for (int i = 0; i < urationalData.Length; i++)
                             Console.Write(@"{0}/{1) ", urationalData[i].Numerator, urationalData[i].Denominator);
                         Console.WriteLine();
                         break;
                 }
             }
         }

         // Clean up
         codecs.Dispose();
     }

static class LEAD_VARS
{
   public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images";
}
RasterCodecsExamples.prototype.CommentsExample = function  ( ) 
{
   Tools.SetLicense ( ) ;
   with ( Leadtools ) { with ( Leadtools.Codecs ) { 
      var codecs = new RasterCodecs();

      var srcFileName = "Assets\\Image1.cmp";
      var destFileName = "Image1_Comments.tif";
      var saveFile ;
      var loadFile;
      // Convert the source file to TIF
      return Tools.AppInstallFolder().getFileAsync(srcFileName).then(function (loadFileX) {
         loadFile = loadFileX;
         return Tools.AppLocalFolder().createFileAsync(destFileName)})
      .then ( function ( saveFileX ) {
         saveFile = saveFileX ;
         console.info("Converting the source file to TIF");
         return codecs.convertAsync(LeadStreamFactory.create(loadFile), LeadStreamFactory.create(saveFile), RasterImageFormat.tif, 0, 0, 24, null)})
      .then ( function ( ) {

         // Add the artist comment
         var writeComment = new RasterCommentMetadata();
         writeComment.type = RasterCommentMetadataType.artist;
         writeComment.fromAscii("LEADTOOLS");

         console.info("Writing the following comment:");
         console.info(" Type:", writeComment.type, ", Data:", writeComment.toAscii());

         return codecs.writeCommentAsync(LeadStreamFactory.create(saveFile), 1, writeComment)})
      .then ( function ( ) {

         // Read the comment back
         
         return codecs.readCommentAsync(LeadStreamFactory.create(saveFile), 1, RasterCommentMetadataType.artist)})
      .then ( function ( readComment ) {
         console.info("The following comment has been read:");
         console.info(" Type:", readComment.type, ", Data:", readComment.toAscii());

         // Write a few comments to the file in one pass
         var comments = [];
         
         writeComment = new RasterCommentMetadata();
         writeComment.Type = RasterCommentMetadataType.artist;
         writeComment.fromAscii("LEADTOOLS Again");
         comments[0] = writeComment;

         writeComment = new RasterCommentMetadata();
         writeComment.type = RasterCommentMetadataType.copyright;
         writeComment.fromAscii("(c) 2006");
         comments[1]= writeComment;

         console.info("Writing the following comments to the file:");
         for (var i=0; i < comments.length;i++)
         {
            var comment = comments[i];
            console.info(" Type:", comment.type, ", Data:", comment.toAscii());
         }
         
         return codecs.writeCommentsAsync(LeadStreamFactory.create(saveFile), 1, comments)
      }) 
      .then ( function ( ) {

         // Now get all the comments in the file and show them:
         Debug.writeln("Reading all comments from the file:");

         var tifComments =
           [
              RasterCommentMetadataType.artist,
              RasterCommentMetadataType.copyright,
              RasterCommentMetadataType.dateTime,
              RasterCommentMetadataType.description,
              RasterCommentMetadataType.hostComputer,
              RasterCommentMetadataType.make,
              RasterCommentMetadataType.model,
              RasterCommentMetadataType.nameOfDocument,
              RasterCommentMetadataType.nameOfPage,
              RasterCommentMetadataType.Software
           ];

         var promises = tifComments.map ( function ( tifComment ) {
         
            return codecs.readCommentAsync(LeadStreamFactory.create(saveFile), 1, tifComment).then ( function ( comment ) {
               if (comment != null)
               {
                  console.info("Found comment, Type:", comment.type, ", Data:");

                  var dataType = RasterCommentMetadata.getDataType(comment.Type);

                  var byteData;
                  var shortData;
                  var rationalData;
                  var urationalData;

                  switch (dataType)
                  {
                     case RasterCommentMetadataDataType.ascii:
                        console.info(comment.toAscii());
                        break;

                     case RasterCommentMetadataDataType.byte:
                        byteData = comment.toByte();
                        for (var i = 0; i < byteData.length; i++)
                           console.info(byteData[i]);
                        console.info("");
                        break;

                     case RasterCommentMetadataDataType.int16:
                        shortData = comment.toInt16();
                        for (var i = 0; i < shortData.length; i++)
                           console.info(shortData[i]);
                        console.info("");
                        break;

                     case RasterCommentMetadataDataType.rational:
                        rationalData = comment.toRational();
                        for (var i = 0; i < rationalData.length; i++)
                           console.info(rationalData[i].numerator, "//", rationalData[i].denominator);
                        console.info("");
                        break;

                     case RasterCommentMetadataDataType.urational:
                        urationalData = comment.toURational();
                        for (var i = 0; i < urationalData.length; i++)
                           console.info(urationalData[i].numerator, "//", urationalData[i].denominator);
                        console.info("");
                        break;
                  }
               }
            });
         });

         return WinJS.Promise.join ( promises )})
         .then ( function ( ) {
            // Clean up
            codecs.close();});
   }
   }
}
[TestMethod]
public async Task CommentsExample()
{
   RasterCodecs codecs = new RasterCodecs();
   string srcFileName = @"Assets\Image1.cmp";
   string destFileName = "Image1_Comments.tif";

   // Convert the source file to TIF
   StorageFile loadFile = await Tools.AppInstallFolder.GetFileAsync(srcFileName);
   StorageFile saveFile = await Tools.AppLocalFolder.CreateFileAsync(destFileName);
   Debug.WriteLine("Converting the source file to TIF");
   await codecs.ConvertAsync(LeadStreamFactory.Create(loadFile), LeadStreamFactory.Create(saveFile), RasterImageFormat.Tif, 0, 0, 24, null);

   // Add the artist comment
   RasterCommentMetadata writeComment = new RasterCommentMetadata();
   writeComment.Type = RasterCommentMetadataType.Artist;
   writeComment.FromAscii("LEADTOOLS");

   Debug.WriteLine("Writing the following comment:");
   Debug.WriteLine(" Type:{0}, Data:{1}", writeComment.Type, writeComment.ToAscii());

   await codecs.WriteCommentAsync(LeadStreamFactory.Create(saveFile), 1, writeComment);

   // Read the comment back
   RasterCommentMetadata readComment = await codecs.ReadCommentAsync(LeadStreamFactory.Create(saveFile), 1, RasterCommentMetadataType.Artist);
   Debug.WriteLine("The following comment has been read:");
   Debug.WriteLine(" Type:{0}, Data:{1}", readComment.Type, readComment.ToAscii());

   // Write a few comments to the file in one pass
   List<RasterCommentMetadata> comments = new List<RasterCommentMetadata>();
   writeComment = new RasterCommentMetadata();
   writeComment.Type = RasterCommentMetadataType.Artist;
   writeComment.FromAscii("LEADTOOLS Again");
   comments.Add(writeComment);

   writeComment = new RasterCommentMetadata();
   writeComment.Type = RasterCommentMetadataType.Copyright;
   writeComment.FromAscii("(c) 2006");
   comments.Add(writeComment);

   Debug.WriteLine("Writing the following comments to the file:");
   foreach (RasterCommentMetadata comment in comments)
      Debug.WriteLine(" Type:{0}, Data:{1}", comment.Type, comment.ToAscii());

   await codecs.WriteCommentsAsync(LeadStreamFactory.Create(saveFile), 1, comments);

   // Now get all the comments in the file and show them:
   Debug.WriteLine("Reading all comments from the file:");

   RasterCommentMetadataType[] tifComments =
     {
        RasterCommentMetadataType.Artist,
        RasterCommentMetadataType.Copyright,
        RasterCommentMetadataType.DateTime,
        RasterCommentMetadataType.Description,
        RasterCommentMetadataType.HostComputer,
        RasterCommentMetadataType.Make,
        RasterCommentMetadataType.Model,
        RasterCommentMetadataType.NameOfDocument,
        RasterCommentMetadataType.NameOfPage,
        RasterCommentMetadataType.Software,
     };

   foreach (RasterCommentMetadataType tifComment in tifComments)
   {
      RasterCommentMetadata comment = await codecs.ReadCommentAsync(LeadStreamFactory.Create(saveFile), 1, tifComment);
      if (comment != null)
      {
         Debug.WriteLine("Found comment, Type:{0}, Data:", comment.Type);

         RasterCommentMetadataDataType dataType = RasterCommentMetadata.GetDataType(comment.Type);

         byte[] byteData;
         short[] shortData;
         RasterMetadataRational[] rationalData;
         RasterMetadataURational[] urationalData;

         switch (dataType)
         {
            case RasterCommentMetadataDataType.Ascii:
               Debug.WriteLine(comment.ToAscii());
               break;

            case RasterCommentMetadataDataType.Byte:
               byteData = comment.ToByte();
               for (int i = 0; i < byteData.Length; i++)
                  Debug.WriteLine("{0:X} ", byteData[i]);
               Debug.WriteLine("");
               break;

            case RasterCommentMetadataDataType.Int16:
               shortData = comment.ToInt16();
               for (int i = 0; i < shortData.Length; i++)
                  Debug.WriteLine("{0:X} ", shortData[i]);
               Debug.WriteLine("");
               break;

            case RasterCommentMetadataDataType.Rational:
               rationalData = comment.ToRational();
               for (int i = 0; i < rationalData.Length; i++)
                  Debug.WriteLine(@"{0}/{1) ", rationalData[i].Numerator, rationalData[i].Denominator);
               Debug.WriteLine("");
               break;

            case RasterCommentMetadataDataType.URational:
               urationalData = comment.ToURational();
               for (int i = 0; i < urationalData.Length; i++)
                  Debug.WriteLine(@"{0}/{1) ", urationalData[i].Numerator, urationalData[i].Denominator);
               Debug.WriteLine("");
               break;
         }
      }
   }

   // Clean up
   codecs.Dispose();
}
public void CommentsExample(Stream inStreamCmp, Stream outStreamTif)
{
   RasterCodecs codecs = new RasterCodecs();
   // Convert the source file to TIF
   Debug.WriteLine("Converting the source file to TIF");
   codecs.Convert(inStreamCmp, outStreamTif, RasterImageFormat.Tif, 0, 0, 24, null);

   // Add the artist comment
   RasterCommentMetadata writeComment = new RasterCommentMetadata();
   writeComment.Type = RasterCommentMetadataType.Artist;
   writeComment.FromAscii("LEADTOOLS");

   Debug.WriteLine("Writing the following comment:");
   Debug.WriteLine(" Type:{0}, Data:{1}", writeComment.Type, writeComment.ToAscii());

   codecs.WriteComment(outStreamTif, 1, writeComment);

   // Read the comment back
   RasterCommentMetadata readComment = codecs.ReadComment(outStreamTif, 1, RasterCommentMetadataType.Artist);
   Debug.WriteLine("The following comment has been read:");
   Debug.WriteLine(" Type:{0}, Data:{1}", readComment.Type, readComment.ToAscii());

   // Write a few comments to the file in one pass
   RasterCollection<RasterCommentMetadata> comments = new RasterCollection<RasterCommentMetadata>();
   writeComment = new RasterCommentMetadata();
   writeComment.Type = RasterCommentMetadataType.Artist;
   writeComment.FromAscii("LEADTOOLS Again");
   comments.Add(writeComment);

   writeComment = new RasterCommentMetadata();
   writeComment.Type = RasterCommentMetadataType.Copyright;
   writeComment.FromAscii("(c) 2006");
   comments.Add(writeComment);

   Debug.WriteLine("Writing the following comments to the file:");
   foreach(RasterCommentMetadata comment in comments)
      Debug.WriteLine(" Type:{0}, Data:{1}", comment.Type, comment.ToAscii());

   codecs.WriteComments(outStreamTif, 1, comments);

   // Now get all the comments in the file and show them:
   Debug.WriteLine("Reading all comments from the file:");

   RasterCommentMetadataType[] tifComments =
   {
      RasterCommentMetadataType.Artist,
      RasterCommentMetadataType.Copyright,
      RasterCommentMetadataType.DateTime,
      RasterCommentMetadataType.Description,
      RasterCommentMetadataType.HostComputer,
      RasterCommentMetadataType.Make,
      RasterCommentMetadataType.Model,
      RasterCommentMetadataType.NameOfDocument,
      RasterCommentMetadataType.NameOfPage,
      RasterCommentMetadataType.Software,
   };

   foreach(RasterCommentMetadataType tifComment in tifComments)
   {
      RasterCommentMetadata comment = codecs.ReadComment(outStreamTif, 1, tifComment);
      if(comment != null)
      {
         Debug.WriteLine("Found comment, Type:{0}, Data:", comment.Type);

         RasterCommentMetadataDataType dataType = RasterCommentMetadata.GetDataType(comment.Type);

         byte[] byteData;
         short[] shortData;
         RasterMetadataRational[] rationalData;
         RasterMetadataURational[] urationalData;

         switch(dataType)
         {
            case RasterCommentMetadataDataType.Ascii:
               Debug.WriteLine(comment.ToAscii());
               break;

            case RasterCommentMetadataDataType.Byte:
               byteData = comment.ToByte();
               for(int i = 0; i < byteData.Length; i++)
                  Debug.WriteLine("{0:X} ", byteData[i]);
               Debug.WriteLine("");
               break;

            case RasterCommentMetadataDataType.Int16:
               shortData = comment.ToInt16();
               for(int i = 0; i < shortData.Length; i++)
                  Debug.WriteLine("{0:X} ", shortData[i]);
               Debug.WriteLine("");
               break;

            case RasterCommentMetadataDataType.Rational:
               rationalData = comment.ToRational();
               for(int i = 0; i < rationalData.Length; i++)
                  Debug.WriteLine(@"{0}/{1) ", rationalData[i].Numerator, rationalData[i].Denominator);
               Debug.WriteLine("");
               break;

            case RasterCommentMetadataDataType.URational:
               urationalData = comment.ToURational();
               for(int i = 0; i < urationalData.Length; i++)
                  Debug.WriteLine(@"{0}/{1) ", urationalData[i].Numerator, urationalData[i].Denominator);
               Debug.WriteLine("");
               break;
         }
      }
   }
}
Public Sub CommentsExample(ByVal inStreamCmp As Stream, ByVal outStreamTif As Stream)
   Dim codecs As RasterCodecs = New RasterCodecs()
   ' Convert the source file to TIF
   Debug.WriteLine("Converting the source file to TIF")
   codecs.Convert(inStreamCmp, outStreamTif, RasterImageFormat.Tif, 0, 0, 24, Nothing)

   ' Add the artist comment
   Dim writeComment As RasterCommentMetadata = New RasterCommentMetadata()
   writeComment.Type = RasterCommentMetadataType.Artist
   writeComment.FromAscii("LEADTOOLS")

   Debug.WriteLine("Writing the following comment:")
   Debug.WriteLine(" Type:{0}, Data:{1}", writeComment.Type, writeComment.ToAscii())

   codecs.WriteComment(outStreamTif, 1, writeComment)

   ' Read the comment back
   Dim readComment As RasterCommentMetadata = codecs.ReadComment(outStreamTif, 1, RasterCommentMetadataType.Artist)
   Debug.WriteLine("The following comment has been read:")
   Debug.WriteLine(" Type:{0}, Data:{1}", readComment.Type, readComment.ToAscii())

   ' Write a few comments to the file in one pass
   Dim comments As RasterCollection(Of RasterCommentMetadata) = New RasterCollection(Of RasterCommentMetadata)()
   writeComment = New RasterCommentMetadata()
   writeComment.Type = RasterCommentMetadataType.Artist
   writeComment.FromAscii("LEADTOOLS Again")
   comments.Add(writeComment)

   writeComment = New RasterCommentMetadata()
   writeComment.Type = RasterCommentMetadataType.Copyright
   writeComment.FromAscii("(c) 2006")
   comments.Add(writeComment)

   Debug.WriteLine("Writing the following comments to the file:")
   For Each comment As RasterCommentMetadata In comments
      Debug.WriteLine(" Type:{0}, Data:{1}", comment.Type, comment.ToAscii())
   Next comment

   codecs.WriteComments(outStreamTif, 1, comments)

   ' Now get all the comments in the file and show them:
   Debug.WriteLine("Reading all comments from the file:")

   Dim tifComments As RasterCommentMetadataType() = {RasterCommentMetadataType.Artist, RasterCommentMetadataType.Copyright, RasterCommentMetadataType.DateTime, RasterCommentMetadataType.Description, RasterCommentMetadataType.HostComputer, RasterCommentMetadataType.Make, RasterCommentMetadataType.Model, RasterCommentMetadataType.NameOfDocument, RasterCommentMetadataType.NameOfPage, RasterCommentMetadataType.Software}

   For Each tifComment As RasterCommentMetadataType In tifComments
      Dim comment As RasterCommentMetadata = codecs.ReadComment(outStreamTif, 1, tifComment)
      If Not comment Is Nothing Then
         Debug.WriteLine("Found comment, Type:{0}, Data:", comment.Type)

         Dim dataType As RasterCommentMetadataDataType = RasterCommentMetadata.GetDataType(comment.Type)

         Dim byteData As Byte()
         Dim shortData As Short()
         Dim rationalData As RasterMetadataRational()
         Dim urationalData As RasterMetadataURational()

         Select Case dataType
            Case RasterCommentMetadataDataType.Ascii
               Debug.WriteLine(comment.ToAscii())

            Case RasterCommentMetadataDataType.Byte
               byteData = comment.ToByte()
               Dim i As Integer = 0
               Do While i < byteData.Length
                  Debug.WriteLine("{0:X} ", byteData(i))
                  i += 1
               Loop
               Debug.WriteLine("")

            Case RasterCommentMetadataDataType.Int16
               shortData = comment.ToInt16()
               Dim i As Integer = 0
               Do While i < shortData.Length
                  Debug.WriteLine("{0:X} ", shortData(i))
                  i += 1
               Loop
               Debug.WriteLine("")

            Case RasterCommentMetadataDataType.Rational
               rationalData = comment.ToRational()
               Dim i As Integer = 0
               Do While i < rationalData.Length
                  Debug.WriteLine("{0}/{1) ", rationalData(i).Numerator, rationalData(i).Denominator)
                  i += 1
               Loop
               Debug.WriteLine("")

            Case RasterCommentMetadataDataType.URational
               urationalData = comment.ToURational()
               Dim i As Integer = 0
               Do While i < urationalData.Length
                  Debug.WriteLine("{0}/{1) ", urationalData(i).Numerator, urationalData(i).Denominator)
                  i += 1
               Loop
               Debug.WriteLine("")
         End Select
      End If
   Next tifComment
End Sub
Requirements

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

See Also

Reference

RasterCodecs Class
RasterCodecs Members
Overload List
Implementing Extended FlashPix Support
Implementing GIF Features
Implementing TIFF Comments and Tags

 

 

Products | Support | Contact Us | Copyright Notices

© 2006-2012 All Rights Reserved. LEAD Technologies, Inc.