HOW TO: Creating a Searchable PDF from a TIF containing Images using ImageOverText

// Create DocWriter
DocumentWriter docWriter = new DocumentWriter();

// Initialize Ocr engine
IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Advantag

// Start up the engine
ocrEngine.Startup(null, docWriter, null, null);

using (RasterCodecs codecs = new RasterCodecs())
{

   codecs.Load(originalFile);

   // Change the PDF options
   PdfDocumentOptions pdfOptions = docWriter.GetOptions(DocumentFormat.Pdf) as PdfDocumentOptions;

   // Set ImageOverText to true to keep layout of original image
   pdfOptions.ImageOverText = true;

   docWriter.SetOptions(DocumentFormat.Pdf, pdfOptions);

   // Create a new PDF document 
   Console.WriteLine("Creating new PDF document: {0}", outputFileName);

   docWriter.BeginDocument(outputFileName, DocumentFormat.Pdf);

   // Ocr document
   using (IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument())
   {
      IOcrPage ocrPage = ocrDocument.Pages.AddPage(originalFile, null);
      ocrPage.Recognize(null);
      ocrDocument.Save(outputFileName, DocumentFormat.Pdf, null);
   }
}