public static Image DrawOn(string imagePath, WatermarkerConfig config)
{
var image = Image.FromFile(imagePath);
var watermarkPath = $@"{Directory.GetCurrentDirectory()}\Images\watermark.png";
var watermark = Properties.Resources.watermark;
//var watermark = Image.FromFile(watermarkPath);
if (!config.Margin.AllEqual(0) || config.ScaleRatio != 1.0f)
{
watermark = RedrawWatermarkWithMargins(watermark, config.Margin, config.ScaleRatio);
}
if (image == null)
{
throw new NullReferenceException("Image to draw on cannot be null.");
}
if (watermark == null)
{
throw new NullReferenceException("Watermark cannot be null.");
}
if (config.Opacity < 0 || config.Opacity > 1)
{
throw new ArgumentOutOfRangeException("Opacity");
}
if (config.ScaleRatio <= 0)
{
throw new ArgumentOutOfRangeException("ScaleRatio");
}
watermark.RotateFlip(config.RotateFlip);
var watermarkPosition = image.GetWatermarkPosition(watermark, config);
var destRect = new Rectangle(watermarkPosition.X, watermarkPosition.Y, watermark.Width, watermark.Height);
var colorMatrix = new ColorMatrix();
colorMatrix.Matrix33 = config.Opacity;
var imageAttributes = new ImageAttributes();
imageAttributes.SetColorMatrix(colorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);
if (config.TransparentColor != Color.Empty)
{
imageAttributes.SetColorKey(config.TransparentColor, config.TransparentColor);
}
using (var graphics = Graphics.FromImage(image))
{
graphics.DrawImage(watermark, destRect, 0, 0, watermark.Width, watermark.Height, GraphicsUnit.Pixel, imageAttributes);
}
return(image);
}
private static System.Drawing.Point GetWatermarkPosition(this Image image, Bitmap watermark, WatermarkerConfig config)
{
int x = 0;
int y = 0;
switch (config.Position)
{
case WatermarkPosition.Absolute:
x = config.PositionX; y = config.PositionY;
break;
case WatermarkPosition.TopLeft:
x = 0; y = 0;
break;
case WatermarkPosition.TopRight:
x = image.Width - watermark.Width; y = 0;
break;
case WatermarkPosition.TopMiddle:
x = (image.Width - watermark.Width) / 2; y = 0;
break;
case WatermarkPosition.BottomLeft:
x = 0; y = image.Height - watermark.Height;
break;
case WatermarkPosition.BottomRight:
x = image.Width - watermark.Width; y = image.Height - watermark.Height;
break;
case WatermarkPosition.BottomMiddle:
x = (image.Width - watermark.Width) / 2; y = image.Height - watermark.Height;
break;
case WatermarkPosition.MiddleLeft:
x = 0; y = (image.Height - watermark.Height) / 2;
break;
case WatermarkPosition.MiddleRight:
x = image.Width - watermark.Width; y = (image.Height - watermark.Height) / 2;
break;
case WatermarkPosition.Center:
x = (image.Width - watermark.Width) / 2; y = (image.Height - watermark.Height) / 2;
break;
default:
break;
}
return(new System.Drawing.Point(x, y));
}
