Show image with watermark dynamic using code

Task: Show Image With Watermark dynamically using Asp.net and C# code.

Description: Sometime we need to add watermark with image on website so that no one can copy and reuse it. So that we can do it by a vary simple way using our back-end code. Here I write a code for achieving this task.
Here we can use image URL to that page URL where we write a code for merging these two images. And in code file I make a function for it we can call it in page_load event. In this function we have to pass both image URL, our image and watermark (watermark should be less then of image size - I will work later for resolve this issue also) and two points x and y for watermark position on that image (these points should be appropriate I also resolve this issue in my next post).
Watermark image should be "PNG" for better result.

Here I show the repetitive watermark on image, You can use it single or anyway as you w...
  

Call the page where you code for image merging :

Image1.ImageUrl = "dynamicimage.aspx";

 

Dynamic Code for image generation and merging (dynamicimage.aspx.cs)

using System.Drawing;

using System.Drawing.Drawing2D;

using System.Drawing.Imaging;

using System.IO;

protected void Page_Load(object sender, EventArgs e)

{

string ThumbnailPath = Server.MapPath(@"images/testimage.jpg");

string watermark =Server.MapPath(@"images/watermark.png");

drawimagewm(ThumbnailPath, watermark, 50, 50);

}

public void drawimage(string imageurl, string watermark, int startx, int starty)

{

    string ThumbnailPath = imageurl;

    string Thumb_WMPath = watermark;

    System.Drawing.Image image = System.Drawing.Image.FromFile(ThumbnailPath);

    System.Drawing.Image img_WM = System.Drawing.Image.FromFile(Thumb_WMPath);

    int width = image.Width;

    int height = image.Height;

    int width2 = img_WM.Width;

    int height2 = img_WM.Height;

    System.Drawing.Graphics graphics = System.Drawing.Graphics.FromImage(image);

    graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;

    graphics.SmoothingMode = SmoothingMode.HighQuality;

    graphics.PixelOffsetMode = PixelOffsetMode.HighQuality;

    graphics.CompositingQuality = CompositingQuality.HighQuality;

    if (startx > (width - width2) || starty > (height - (height2)))

    {

        graphics.DrawImage(image2, new Point(startx, starty));

    }

// I use 50 for gapping between two watermark...

    for (int i = startx; i < (width - (width2)); i = i + width2 + 50)

    {

        for (int j = starty; j < (height - (height2)); j = j + height2 + 50)

        {

            graphics.DrawImage(img_WM, new Point(i, j));

        }

    }

    ImageCodecInfo[] info = ImageCodecInfo.GetImageEncoders();

    EncoderParameters encoderParameters;

    encoderParameters = new EncoderParameters(1);

    encoderParameters.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 100L);

    string sExt = System.IO.Path.GetExtension(ThumbnailPath);

    Response.ContentType = "image/jpeg";

    if (sExt.ToString() == ".jpg" || sExt.ToString() == ".jpeg")

    {

        image.Save(Response.OutputStream, info[1], encoderParameters);

    }

    else

    {

        image.Save(Response.OutputStream, image.RawFormat);

    }

    image.Dispose();

    img_WM.Dispose();

}