title: Measuring distances from a time series of images in R, for snow-depth calculation
body: <p>I am looking to calculate snow-depth for a timeseries of timelapse images in R.  In each image there is a snow stake that represents a certain length from which we can get snow depth from.  I wish to instead of reading the depth form each image, automate this process.</p>
  <p>My idea is to first draw a reference line over the length of the snow stake, so we know how long the snow stake is in pixels. Then to, as it snows, reduce or grow that line based on the snow line, or automatically redraw the line to where the snow starts. I am wondering, a)whether this can be done, b)if any one has tried something similar to this and c)whether someone can point me in the right direction on where to start the process.</p>
  <p>Currently I have tried drawing the line and then using edge detection to automatically redraw the line for every picture and then measure that line, but there is too much noise and our snow stakes don't stand out enough.  I have also been using the magick package but haven't found a viable solution yet.  Let me know if you have any ideas! Thanks!</p>
  <p>Here is an example of a snow stake site in summer.</p>
  <p><a href="https://i.stack.imgur.com/7dvhI.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/7dvhI.jpg" alt="more than one moose" /></a></p>