title: How to crop a portion from tiff image
body: <p>Here is my TIFF image and I am trying to extract left rectangle or box from the tiff image and save as a PNG file.</p>
  
  <p><img src="https://i.stack.imgur.com/5NC07.png" alt="enter image description here"></p>
  
  <p>the left side rectangle or box portion i tried to crop programmatically. here is my routine.</p>
  
  <pre><code>strImageFilePath = @"C:\Users\TRIDIP\Desktop\PDF\getLabel.tif";
  var source = LoadImage(strImageFilePath);
  Rectangle crop = new Rectangle(100, 160, 920, 1200);
  var bmp = new Bitmap(920, 1200);
  using (var gr = Graphics.FromImage(bmp))
  {
    gr.DrawImage(source, new Rectangle(0, 0, bmp.Width, bmp.Height), crop, GraphicsUnit.Pixel);
    bmp.Save(@"C:\Users\TRIDIP\Desktop\PDF\Tile.png");
  }
  </code></pre>
  
  <p>but the problem is coordinate calculation.</p>
  
  <pre><code>Rectangle crop = new Rectangle(100, 160, 920, 1200);
  var bmp = new Bitmap(920, 1200);
  </code></pre>
  
  <p>The value I gave above is not perfect and that is why the exact portion is not cropped. so some one please download the image and tell me what top,left and height and width i should specify in my code as a result left box can be perfectly cropped from the image. just help me to get the right coordinate means tell me exact figure for top, left and height and width.</p>