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Dual Streaming: What Should I Know?

People rely on cameras more and more and, likewise, the requirements to their performance grow quickly. Those of us who are capable of multitasking are well-respected. Interestingly enough, this applies to cameras as well. But how can a camera, meant only for video surveillance, do anything else?

First, a bit of history. The very first closed-circuit television (CCTV) system was installed all the way back in 1942. Needless to say, it wasn’t particularly convenient to use and until 1970s all the cameras required manual maintenance (it consisted of taking the magnetic tape and threading it through the recorder onto an empty take-up reel). 1970s saw the invention of videocassette recorders (VCRs), which simplified things greatly by allowing automatic recording or deleting of footage. Finally, enter digital cameras able to store high quality footage on compact memory cards or even transmitting it at a significant distance. dual_streaming_cctv

As you see, the CCTV’s development is measured by how efficient it is at dealing with the footage. Dual streaming is simply the new step in cameras’ evolution. Modern cameras need to provide live feed to the monitor(s) (often wirelessly) AND save the footage for future reference (usually locally). This is no easy feat tending to put a lot of strain on the Internet traffic. But what makes videos so hard to transmit is their resolution (basically, quality), thus, if you save the higher resolution for local storage and show live feed in lower resolution, you get a significant drop in traffic load. That is dual streaming.

dual_streaming_high_quality A rather important part of this feature is a video compression standard called “H.264”. It was created in 2003 by the Video Coding Experts Group (VCEG) and the Moving Picture Experts Group (that’s right, MPEG). The goal was to HALVE the bit rate (traffic load) required for rendering any given video. And, believe it or not, they succeeded. H.264 is a compression standard that provides high quality while keeping the bit rate to the minimum. Using it for actual streaming yields decent results. Services that rely on it are numerous: YouTube, Vimeo, even Blu-ray discs and many others. Moreover, it can help in reducing the CPU load as well.

Dual streaming’s popularity is growing steadily and H.264’s successor – H.265 – is being enhanced as we speak. With this we can enjoy high quality videos from the comfort of our chairs without overstraining the traffic.