title: Check for Text within an Image C#. Is using memcmp an option?
body: <p>I'm working on a research project which requires me to identify text within an image. Over the forum I saw a post of using memcmp, but I'm having no luck with this.</p>
  
  <p>To give more details on my task :</p>
  
  <p>I screen capture this. My image reads "GPS: Initial Location 34 45 23". </p>
  
  <p>I then dip into a predefined map of images that I load at the start of my application.The map contains images for text - Initial, Reset, Launch, ....</p>
  
  <p>How do I check if the image I captured matches to one of the predefined images in the map. </p>
  
  <p>Kindly help.</p>
  
  <p>Attaching a snapshot of code</p>
  
  <pre><code>public static bool CompareMemCmp(Bitmap b1, Bitmap b2)
  {
    if ((b1 == null) != (b2 == null)) return false;
  
    var bd1 = b1.LockBits(new Rectangle(new Point(0, 0), b1.Size), ImageLockMode.ReadOnly, b1.PixelFormat);
    var bd2 = b2.LockBits(new Rectangle(new Point(0, 0), b2.Size), ImageLockMode.ReadOnly, b2.PixelFormat);
  
    try
    {
      IntPtr bd1scan0 = bd1.Scan0;
      IntPtr bd2scan0 = bd2.Scan0;
  
      int stride = bd1.Stride;
      int len = stride * b1.Height;
  
      int stride2 = bd2.Stride;
      int len2 = stride2 * b2.Height;
  
      for (int i = 0; i &lt; len; ++i)
      {
        bd1scan0 = bd1.Scan0 + i;
  
        int test = memcmp(bd1scan0, bd2scan0, len2);
        if (test == 0)
        {
          Console.WriteLine("Found the string");
          return true;
        }
      }
  
      return false;
    }
    finally
    {
      b1.UnlockBits(bd1);
      b2.UnlockBits(bd2);
    }
  }
  </code></pre>