// For complete examples and data files, please go to https://github.com/groupdocs-watermark/GroupDocs.Watermark-for-.NET
using (CellsDocument doc = Document.Load<CellsDocument>(Utilities.MapSourceFilePath (FilePath)))
{
using (var watermark = new ImageWatermark(@"D:\logo.tif"))
{
CellsImageEffects effects = new CellsImageEffects();
effects.Brightness = 0.7;
effects.Contrast = 0.6;
effects.ChromaKey = Color.Red;
effects.BorderLineFormat.Enabled = true;
effects.BorderLineFormat.Weight = 1;
doc.AddImageWatermark(watermark, effects);
}
doc.Save();
}