senthil88

Step 1 - Follow install and setup instructions for janus, gst-launch1.0, nginx (and required dependencies)

https://www.rs-online.com/designspark/building-a-raspberry-pi-2-webrtc-camera

Step 2 - Launch Janus

./janus -F /opt/janus/etc/janus/

Step 3 - Start streaming from webcam

gst-launch-1.0 v4l2src ! 'video/x-raw, width=640, height=480, framerate=30/1' ! videoconvert ! x264enc pass=qual quantizer=20 tune=zerolatency ! rtph264pay ! udpsink host=127.0.0.1 port=8004

Step 4 - Open demo page in browser

senthil88

Fast/efficient approach:

-- execute("UPDATE posts SET comments_count = (SELECT count(1) FROM comments WHERE comments.post_id = posts.id)")
   -> 1.3197s

Slow/naïve approach:

senthil88

  def point_in_polygon?(polygonPoints)
    return false if self.latitude.blank? or self.longitude.blank?
    polygonPoints.each do |point|
      point[0] = point[0].to_f
      point[1] = point[1].to_f
    end

    contains_point = false
    i = -1
    j = polygonPoints.size - 1

senthil88

How to change your commit messages in Git?

At some point you’ll find yourself in a situation where you need edit a commit message. That commit might already be pushed or not, be the most recent or burried below 10 other commits, but fear not, git has your back 🙂.

Not pushed + most recent commit:

git commit --amend

This will open your $EDITOR and let you change the message. Continue with your usual git push origin master.