Add an image watermark on an image file, not work

Aspose.Imaging Product Family
1

I want to add a png file as watermark on tiff file. I used Aspose.Imaging.Brushes.TextureBrush class,but it did not work. Also I did not find method to set opacity of the watermark and I dont know if the watermark could keep the original color but not turn black and white.

Here is my current test code

using (Aspose.Imaging.Image image = Aspose.Imaging.Image.Load(img))
{
    // Load the watermark image
    string watermarkPath = @"D:\AI\水印.png";
    using (Aspose.Imaging.Image watermark = Aspose.Imaging.Image.Load(watermarkPath))
    {
        // Set the watermark position and scale
        double x = 100;
        double y = 100;
        double width = 200;
        double height = 200;

        // Create a brush from the watermark image
        var brush = new Aspose.Imaging.Brushes.TextureBrush(watermark);

        // Add the watermark to the TIF file
        Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(image);

        graphics.FillRectangle(brush, new Aspose.Imaging.RectangleF((float)x, (float)y, (float)width, (float)height));

        // Save the modified TIF file
        string savePath = Path.Combine(@"C:\Users\xj2ssf\Desktop\EDM_test",
                string.Format("{0}_{1}{2}", Path.GetFileNameWithoutExtension(img),
                                            DateTime.Now.ToString("yyyy_MM_dd_hh_mm_fff"),
                                            Path.GetExtension(img)));
        image.Save(savePath);
    }
}
2

@msdos41, such question was asked before and answered in topic How do you add a transparent image watermark to an image? , you can use this answer.