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    <p>Right, I've just downloaded a PDF of the book, installed Emgu CV, and followed the same process as you did. Except I succeeded ;-)</p> <p>I think all you missed was that you need to create an empty 32-bit float image to receive the corner strengths before you call <code>cvCornerHarris</code>. Then you pass the <code>Image</code> objects to it.</p> <p>Here are the main parts of my code, which I developed in a Windows Forms application in C# using Visual Studio 2012. First, a few member variables I used to hold the image objects:</p> <pre><code>// original source image as grayscale private Image&lt;Gray, Byte&gt; m_SourceImage = null; // raw corner strength image (must be 32-bit float) private Image&lt;Gray, float&gt; m_CornerImage = null; // inverted thresholded corner strengths (for display) private Image&lt;Gray, Byte&gt; m_ThresholdImage = null; </code></pre> <p>Now, a button click handler to prompt for an image to load from file and display it:</p> <pre><code>private void button1_Click(object sender, EventArgs e) { // prompt for source image OpenFileDialog Openfile = new OpenFileDialog(); if (Openfile.ShowDialog() == DialogResult.OK) { // create and show source image as grayscale m_SourceImage = new Image&lt;Gray, byte&gt;(Openfile.FileName); pictureBox1.Image = m_SourceImage.ToBitmap(); } } </code></pre> <p>Finally, the button click handler for performing the corner detection:</p> <pre><code>private void button2_Click(object sender, EventArgs e) { // create corner strength image and do Harris m_CornerImage = new Image&lt;Gray, float&gt;(m_SourceImage.Size); CvInvoke.cvCornerHarris(m_SourceImage, m_CornerImage, 3, 3, 0.01); // create and show inverted threshold image m_ThresholdImage = new Image&lt;Gray, Byte&gt;(m_SourceImage.Size); CvInvoke.cvThreshold(m_CornerImage, m_ThresholdImage, 0.0001, 255.0, Emgu.CV.CvEnum.THRESH.CV_THRESH_BINARY_INV); pictureBox1.Image = m_ThresholdImage.ToBitmap(); } </code></pre> <p>In the above code, you can see I have followed the example from the book and applied a threshold to the corner image and inverted the result for easier display. You could just show <code>m_CornerImage</code> instead. </p> <p>Here are some screenshots of the result - the loaded image (as grayscale) on the left, and the inverted threshold image showing the corner strengths on the right:</p> <p><img src="https://i.stack.imgur.com/gMcgH.png" alt="harris"></p> <p>Please comment or edit your question if you need any further information or help and I'll do my best.</p>
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    1. COThank you , I was using Byte instead of float, the bounty will be available to be rewarded in 20 hours , I will make sure to do it
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    2. CO@Musaab - my pleasure - many thanks for the bounty, I'll look forward to it :-)
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