How to Add Watermark to an Image inside .NET Applications
This technical tip explains how .NET developers can add a watermark to an image inside their .NET applications. Adding a watermark to an image is a common requirement for image processing applications. This example uses the Graphics class to draw a string on the image surface. To demonstrate the operation, we will load a BMP image from disk and draw a string as the watermark on the image surface using the Graphics class' DrawString method. We'll save the image to PNG format using the PngOptions class. Below is a code example that demonstrates how to add a watermark to an image. The example source code has been split into parts to make it easy to follow.
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//your code here...// Adding a Watermark
//[C# Code Sample]
//Load an existing JPG image
using (Aspose.Imaging.Image image = Aspose.Imaging.Image.Load(myDir + "sample.jpg"))
{
//Declare a String object with Watermark Text
String theString = "45 Degree Rotated Text";
//Create and initialize an instance of Graphics class
Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(image);
//Initialize an object of SizeF to store image Size
Aspose.Imaging.SizeF sz = graphics.Image.Size;
//Creates an instance of Font, initialize it with Font Face, Size and Style
Aspose.Imaging.Font font = new Aspose.Imaging.Font("Times New Roman", 20, FontStyle.Bold);
//Create an instance of SolidBrush and set its various properties
Aspose.Imaging.Brushes.SolidBrush brush = new Aspose.Imaging.Brushes.SolidBrush();
brush.Color = Aspose.Imaging.Color.Red;
brush.Opacity = 0;
//Initialize an object of StringFormat class and set its various properties
Aspose.Imaging.StringFormat format = new Aspose.Imaging.StringFormat();
format.Alignment = Aspose.Imaging.StringAlignment.Center;
format.FormatFlags = Aspose.Imaging.StringFormatFlags.MeasureTrailingSpaces;
//Create an object of Matrix class for transformation
Aspose.Imaging.Matrix matrix = new Aspose.Imaging.Matrix();
//First a translation
matrix.Translate(sz.Width / 2, sz.Height / 2);
//Then a rotation
matrix.Rotate(-45.0f);
//Set the Transformation through Matrix
graphics.Transform = matrix;
//Draw the string on Image
graphics.DrawString(theString, font, brush, 0, 0, format);
//Save output to disk
image.Save(myDir + "output.jpg");
}
//[VB.NET Code Sample]
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Url: http://www.aspose.com/.net/imaging-component.aspx
Language: C# | User: Sheraz Khan | Created: Dec 30, 2015 | Tags: how to add a watermark to image Adding Watermark to Image draw string on the image surface load BMP image from disk Create & initialize Graphics object .NET image processing