static Image AddWatermark(this Image image)
{
if (Watermark.Image == null || image == null)
{
throw new ArgumentException();
}
var imageResolution = image.GetResolution();
var resultBitmap = new Bitmap((int)imageResolution.Width, (int)imageResolution.Height);
try
{
resultBitmap.SetResolution(image.HorizontalResolution, image.VerticalResolution);
Image watermarkImageCopy = null;
lock (Watermark) { watermarkImageCopy = (Image)Watermark.Image.Clone(); }
using (var graphicCanvas = Graphics.FromImage(resultBitmap))
{
graphicCanvas.CompositingQuality = CompositingQuality.HighQuality;
graphicCanvas.InterpolationMode = InterpolationMode.HighQualityBicubic;
graphicCanvas.SmoothingMode = SmoothingMode.HighQuality;
var watermarkOrginalSize = new RectangleF(0, 0, watermarkImageCopy.Width, watermarkImageCopy.Height);
var watermarkComputedResolution = Watermark.Scale.GetComputedResolution(imageResolution, watermarkImageCopy.GetResolution());
var waterwarkComputedMargin = Watermark.Margin.GetComputedMargin(imageResolution);
var watermarkComputedPosition = Watermark.GetWatermarkPosition(imageResolution, watermarkComputedResolution, waterwarkComputedMargin);
var watermarkColorMatrix = new ColorMatrix();
watermarkColorMatrix.Matrix33 = Watermark.Opacity;
var watermarkImageAttributes = new ImageAttributes();
watermarkImageAttributes.SetColorMatrix(watermarkColorMatrix);
graphicCanvas.DrawImage(image, 0, 0, imageResolution.Width, imageResolution.Height);
graphicCanvas.DrawImage(watermarkImageCopy, watermarkComputedPosition.GetArray(), watermarkOrginalSize, GraphicsUnit.Pixel, watermarkImageAttributes);
}
watermarkImageCopy.Dispose();
return(resultBitmap);
}
catch
{
resultBitmap.Dispose();
throw new ArgumentException();
}
}
