title: Emgu OpenCV: Apply different Threshold values depending on text form[sharp/bold]
body: <p>I want to preprocess a scanned image to do some OCR on it. My problem is that when I apply a given value of Threshold to  remove noise, the bold text become sharp,but the rest of the text disappears. </p>
  
  <pre><code>CvInvoke.cvThreshold(img, img, 80, 255, THRESH.CV_THRESH_BINARY);
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/0tRaQ.jpg" alt="enter image description here"></p>
  
  <pre><code>CvInvoke.cvThreshold(img, img, 120, 255, THRESH.CV_THRESH_BINARY);
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/dMvIU.jpg" alt="enter image description here"></p>
  
  <p>I'm asking if there is a way to apply different values of Threshold depending on text form ?</p>