เพิ่มแสตมป์รูปภาพลงใน PDF ผ่าน C#

var inputFile = Path.Combine(dataDir, "AddImageStamp.pdf");
var outputFile = Path.Combine(dataDir, "AddImageStamp_out.pdf");
var imageStampFile = Path.Combine(dataDir, "aspose-logo.jpg");
var pdfDocument = new Aspose.Pdf.Document(inputFile);

var imageStamp = new Aspose.Pdf.ImageStamp(imageStampFile)
{
    Background = true,
    XIndent = 100,
    YIndent = 100,
    Height = 300,
    Width = 300,
    Rotate = Aspose.Pdf.Rotation.on270,
    Opacity = 0.5
};
        
pdfDocument.Pages[1].AddStamp(imageStamp);
pdfDocument.Save(outputFile);