private void setImageTag(string imgFile, string tagFile, string imgTag, string imgTitle)

 {

     uint padding = ;

     if (File.Exists(imgFile))

     {

         BitmapDecoder decoder = null;

         // load the jpg file with a JpegBitmapDecoder

         using (Stream jpegStreamIn = File.Open(imgFile, FileMode.Open, FileAccess.ReadWrite, FileShare.None))

         {

             decoder = new JpegBitmapDecoder(jpegStreamIn, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.OnLoad);

         }

         if (decoder != null)

         {

             BitmapFrame bitmapFrame = decoder.Frames[];

             if (bitmapFrame != null)

             {

                 // the size of the metadata has been increased and we can't save it

                 BitmapMetadata metaData = (BitmapMetadata)bitmapFrame.Metadata.Clone();

                 if (metaData != null)

                 {

                     // Add padding

                     metaData.SetQuery("/app1/ifd/PaddingSchema:Padding", padding);

                     metaData.Title = imgTitle;

                     List<string> taglist = new List<string>();

                     taglist.Add(imgTag);

                     metaData.Keywords = new System.Collections.ObjectModel.ReadOnlyCollection<string>(taglist);

                     // get an encoder to create a new jpg file with the addit'l metadata.

                     JpegBitmapEncoder encoder = new JpegBitmapEncoder();

                     encoder.Frames.Add(BitmapFrame.Create(bitmapFrame, bitmapFrame.Thumbnail, metaData, bitmapFrame.ColorContexts));

                     using (Stream jpegStreamOut = File.Open(tagFile, FileMode.CreateNew, FileAccess.ReadWrite))

                     {

                         encoder.Save(jpegStreamOut);

                     }

                 }

             }

         }

     }

 }