افزودن واترمارک از طریق C#

var inputFile = Path.Combine(dataDir, "sample.pdf");
var imageFile = Path.Combine(dataDir, "watermark.jpeg");
var outputFile = Path.Combine(dataDir, "AddWatermark.pdf");

var pdfDocument = new Aspose.Pdf.Document(inputFile);
var artifact = new Aspose.Pdf.WatermarkArtifact();
artifact.SetImage(imageFile);

artifact.ArtifactHorizontalAlignment = Aspose.Pdf.HorizontalAlignment.Center;
artifact.ArtifactVerticalAlignment = Aspose.Pdf.VerticalAlignment.Center;
artifact.Rotation = 15;
artifact.Opacity = 1;
artifact.IsBackground = true;
pdfDocument.Pages[1].Artifacts.Add(artifact);
pdfDocument.Save(outputFile);