title: Detecting street lamps from google street view with OpenCV
body: <p>I am trying to use OpenCV to detect street lamps from Google Street View.</p>
  
  <p>For now as sample I have 2000 positive images, but only 1200 are around the same ration, so I am using only this for training.</p>
  
  <p>And another 2300 negative images.</p>
  
  <p>Example of positive images:
  <img src="https://i.stack.imgur.com/ecWnm.png" alt="StreetLamp">
  <img src="https://i.stack.imgur.com/pGhkJ.png" alt="StreetLamp">
  <img src="https://i.stack.imgur.com/x37Wt.png" alt="StreetLamp">
  <img src="https://i.stack.imgur.com/3rYXO.png" alt="StreetLamp">
  <img src="https://i.stack.imgur.com/yTAnB.png" alt="StreetLamp"></p>
  
  <p>I tried down sampling them to different sizes, and train them, but for now the detection is really poor, when I test it with images like this:
  <img src="https://i.stack.imgur.com/qSEWl.jpg" alt="Test image[6]"></p>
  
  <p>Depending on <code>detectMultiScale</code> argument I either get a lot of rectangles, including the lamps, or a few rectangles, but not including the actual lamps.</p>
  
  <p>On training, I am modifying mostly height and width parameters, example of parameters: (200, 10) (150, 30), (120, 30). I tried changing also the algorithm from LBP to HAAR, but the results were similar.</p>
  
  <ol>
  <li><p>Do you think I need more then 1000 positive sample?</p></li>
  <li><p>Should I do any extra preprocessing before creating the vector file?</p></li>
  <li><p>Do you have any idea on what parameters I should change to make it working?</p></li>
  <li><p>Is it possible with OpenCV to detect with lamps in google street view images?</p></li>
  </ol>