Small aircraft with streaming video cameras are now widely available, for better or worse. Making eyes in the sky so accessible has resulted in interesting footage that would have been prohibitively expensive to capture a few years ago, but this new creative frontier also has a dark side when used to violate privacy. Those who are covering their tracks by encrypting their video transmission should know researchers at Ben-Gurion University of the Negev demonstrated such protection can be breached.
The BGU team proved that a side-channel analysis can be done against behavior common to video compression algorithms, as certain changes in video input would result in detectable bitrate changes to the output stream. By controlling a target’s visual appearance to trigger these changes, a correlating change in bandwidth consumption would reveal the target’s presence in an encrypted video stream.
Continue reading “Watching the Watchers: Are You The Star Of an Encrypted Drone Video Stream?”
The Raspberry Pi is an incredibly versatile computing platform, particularly when it comes to embedded applications. They’re used in all kinds of security and monitoring projects to take still shots over time, or record video footage for later review. It’s remarkably easy to do, and there’s a wide variety of tools available to get the job done.
However, if you need live video with as little latency as possible, things get more difficult. I was building a remotely controlled vehicle that uses the cellular data network for communication. Minimizing latency was key to making the vehicle easy to drive. Thus I set sail for the nearest search engine and begun researching my problem.
My first approach to the challenge was the venerable VLC Media Player. Initial experiments were sadly fraught with issues. Getting the software to recognize the webcam plugged into my Pi Zero took forever, and when I did get eventually get the stream up and running, it was far too laggy to be useful. Streaming over WiFi and waving my hands in front of the camera showed I had a delay of at least two or three seconds. While I could have possibly optimized it further, I decided to move on and try to find something a little more lightweight.
Continue reading “Video Streaming Like Your Raspberry Pi Depended On It”
Some people will tell you that YouTube has become a vast wasteland of entertainment like the boob tube before it. Live streaming doesn’t help the situation much, and this entry level webcam live-stream server isn’t poised to advance the art.
We jest, but only a little. [Mike Haldas] runs a video surveillance company that sells all manner of web-enabled cameras and wondered what it would take to get a low-end camera set up for live streaming. The first step was converting the Zavio webcam stream from RTSP (real-time streaming protocol) to the standard that YouTube uses, RTMP (real-time messaging protocol). Luckily, FFmpeg handles that conversion, so he compiled it for his MacBook Pro and set up a proof of concept. It worked, but he needed a compact solution that would free up his laptop. Raspberry Pi to the rescue – after loading a bunch of libraries and a four-hour build and install of FFmpeg, the webcam was streaming 1080p video of [Mike]’s sales office. He was worried that the Pi wouldn’t have the power needed for the job, and that it would be unstable. But as of this writing, the stream below has been active for six days, and it’s riveting stuff.
Raspberry Pis are a staple in the audio streaming world, like this pro-grade FM broadcast streaming rack or this minuscule internet radio streamer. And of course there’s this quick and dirty, warm and fuzzy streaming baby monitor.
Continue reading “Low-cost Video Streaming with a Webcam and Raspberry Pi”