HOW TO: Use Virtual LEADDocument to Merge Documents and Images into One Text-searchable PDF File - The DocumentConverter will OCR images only as needed

private static void MergeAndConvertToPdf(IReadOnlyCollection<string> inputFiles)
{
	Console.WriteLine();
	ConsoleHelper.WriteStatus("Converting Files... ");
	using (var documentConverter = new DocumentConverter())
	{
		var firstFile = GetFirst(inputFiles);
		var outputFile = GetNewFilePath(firstFile);

		var loadOptions = new LoadDocumentOptions {UseCache = false};
		var createOptions = new CreateDocumentOptions {UseCache = false};
		documentConverter.SetDocumentWriterInstance(GetDocumentWriter());

		using (var ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.LEAD, false))
		{
			ocrEngine.Startup(null, null, null, null);
			documentConverter.SetOcrEngineInstance(ocrEngine, false);

			using (var masterDocument = DocumentFactory.Create(createOptions))
			{
				masterDocument.AutoDisposeDocuments = true;
				foreach (var inputFile in inputFiles)
					masterDocument.Pages.AddRange(DocumentFactory.LoadFromFile(inputFile, loadOptions).Pages);

				var jobData =
					DocumentConverterJobs.CreateJobData(masterDocument, outputFile, DocumentFormat.Pdf);
				jobData.JobName = "merge and convert job";
				var job = documentConverter.Jobs.CreateJob(jobData);
				documentConverter.Jobs.JobOperation += JobOperationEventHandler;
				documentConverter.Jobs.RunJob(job);
				documentConverter.Jobs.JobOperation -= JobOperationEventHandler;

				DisplayResultMessage(job, outputFile);
			}

			ocrEngine.Shutdown();
		}
	}
}