/// <summary>
/// Draw image watermark.
/// <para>Notice regarding watermark opacity:</para>
/// <para>If watermark image needs to be resized, first resize the watermark image,
/// then save it to the disc, and read it again with Image.FromFile.</para>
/// </summary>
/// <param name="img">The original image</param>
/// <param name="wmImage">Watermak image</param>
/// <param name="ops">Image watermark options <see cref="ImageWatermarkOptions"/></param>
public static Image AddImageWatermark(this Image img, Image wmImage, ImageWatermarkOptions ops)
{
if (ops.Opacity > 0)
{
using (var graphics = Graphics.FromImage(img))
{
graphics.SmoothingMode = SmoothingMode.None;
graphics.CompositingMode = CompositingMode.SourceOver;
if (ops.Opacity < 100)
{
wmImage = ImageOpacity.ChangeImageOpacityMethod1(wmImage, ops.Opacity);
}
var wmW = wmImage.Width;
var wmH = wmImage.Height;
var drawingPoint = ImageWatermarkPosition.ImageWatermarkPos(img.Width, img.Height, wmW, wmH, ops.Location, ops.Margin);
graphics.DrawImage(wmImage, drawingPoint.X, drawingPoint.Y, wmW, wmH);
}
}
wmImage.Dispose();
return(img);
}
/// <summary>
/// Draw image watermark
/// </summary>
/// <param name="img">The original image</param>
/// <param name="wmImgPath">Path to the watermark image file e.g. wwwroot\images\watermark.png</param>
/// <param name="ops">Image watermark options <see cref="ImageWatermarkOptions"/></param>
public static Image AddImageWatermark(this Image img, string wmImgPath, ImageWatermarkOptions ops)
{
var wm = Image.FromFile(wmImgPath);
return(img.AddImageWatermark(wm, ops));
}