Template Matching using C# and Accord .Net

 In this post I am going to show "how to use ExhaustiveTemplateMatching feature is Accord.Net " to detect object i am image.So Lets create a new project and add reference  "Accord.Imaging" to your project.

My Form Design:

In the Select Image Textbox i am going to select the input image and in template image textbox i am going to select the Template image.

Code Behind for Selecting Input Image and Template Image:

 private void btnOpen_Click(object sender, EventArgs e)

        {

            try

            {

                openFileDialog1.Filter = "Jpeg|*.jpg";

                DialogResult dr = openFileDialog1.ShowDialog();

                if (dr == DialogResult.OK)

                {

                    textBox1.Text = openFileDialog1.FileName;

                    PictureInput.Load(openFileDialog1.FileName);

                }

            }

            catch (Exception ex)

            {

                MessageBox.Show("Exception:" + ex.ToString());

            }

        }

//Select Template Image

 private void btnTemplate_Click(object sender, EventArgs e)

        {

            try

            {

                openFileDialog1.Filter = "Jpeg|*.jpg";

                DialogResult dr = openFileDialog1.ShowDialog();

                if (dr == DialogResult.OK)

                {

                    textBox2.Text = openFileDialog1.FileName;

                    //PictureInput.Load(openFileDialog1.FileName);

                }

            }

            catch (Exception ex)

            {

                MessageBox.Show("Exception:" + ex.ToString());

            }

        }

Template Matching Code:

private void btnMatch_Click(object sender, EventArgs e)

        {

            //Converting Template into GrayScale Image            

            Bitmap templateImage = new Bitmap(textBox2.Text);

            Grayscale gg = new GrayscaleBT709();

            Bitmap grayTemplate = gg.Apply(templateImage);

            // create template matching algorithm's instance

            ExhaustiveTemplateMatching tm = new ExhaustiveTemplateMatching(0);

            // find all matchings with specified above similarity

            Bitmap sourceImage = new Bitmap(textBox1.Text);

            Bitmap graySource = gg.Apply(sourceImage);

            

            TemplateMatch[] matchings = tm.ProcessImage(graySource, grayTemplate);

            

            Graphics g = Graphics.FromImage(sourceImage);

            if (matchings[0].Similarity > 0.8f)

            {

                int X = matchings[0].Rectangle.X;

                int Y = matchings[0].Rectangle.Y;

                g.DrawRectangle(new Pen(Color.Red, 3), X, Y, matchings[0].Rectangle.Width, matchings[0].Rectangle.Height);                

                PicTemplate.Image = sourceImage;

                MessageBox.Show("Match found...");

            }

            else

            {

                MessageBox.Show("Match Not Found...");

            }           

        }

Output:

Download Source Code

Source Code