title: Filter out part of a Time Series without using a threshold
body: <p>I have the following Time Series:
  <a href="https://i.stack.imgur.com/qKk5r.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/qKk5r.png" alt="enter image description here"></a></p>
  
  <p>What I want to do is to filter out the points (maybe giving them a nan value) that I circle in orange. Let's say that the main reason to filter them out is because the don't follow the general pattern of the rest of the time series and they have very different values. Is there any filter, like low pass filter or any other idea that can be applied to filter them out?</p>
  
  <p>In this case instead everything would be normal, so I won't filter out any part of the time series:</p>
  
  <p><a href="https://i.stack.imgur.com/FtsNm.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/FtsNm.png" alt="enter image description here"></a></p>
  
  <p>Since I am interested only in the part of the Time Series that have the red points, so the one that show that specific pattern, I don't care if in the process of filtering out the parts circled in orange also the beginning and end of the time series will be filtered out. </p>
  
  <p>The reason why I don't want to use a threshold is that the range of values is different for every time series.</p>