using (RasterCodecs codecs = new RasterCodecs())
{
    string masterFormRepository = @"Invoice Master Form Path";
    string filledFormDirectory = @"Filled Invoice Path";
    using (IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.LEAD, false))
    {
        ocrEngine.Startup(codecs, null, null, null);
        IMasterFormsRepository repository = new DiskMasterFormsRepository(codecs, masterFormRepository);
        using (AutoFormsEngine engine = new AutoFormsEngine(repository, ocrEngine, null, AutoFormsRecognitionManager.Default | AutoFormsRecognitionManager.Ocr, 30, 80, false))
        {
            foreach (var file in Directory.EnumerateFiles(filledFormDirectory))
            {
                using (RasterImage image = codecs.Load(file))
                {
                    //Run the recognition
                    AutoFormsRunResult runResult = engine.Run(image, null, null, null);
                }
            }
        }
    }
}