One of the advantages of having today’s DVRs vs the older time lapse VCRs for recording your security camera footage is the ability to connect the DVR to your network. By doing so, you have just opened up a whole new world of possibilities. Many of todays modern DVRs have a built in web server that would allow you to view your cameras remotely from any internet browser, anywhere in the world that has an internet connection. Some also have sophisticated monitoring software that allows you to monitor your security cameras from multiple locations at the same time. For example, you may have a surveillance system installed in your business, and in your home, and with monitoring software, you could connect to both at the same time. All of this great technology comes at a price. That price is called bandwidth. Gone are the days of the old AOL dial up service that provided 33kbps – 56kbps bandwidth. Today’s typical needs are now in the 3mbps -5mbps and often higher. The most demanding bandwidth hogs on the internet that I can think of are videos. You may think of videos as what you watch on www.youtube.com but a huge amount of bandwidth is used by security camera videos that are streamed from millions of security cameras over the internet every minute of every day. As the quality of today’s security cameras increase, the size of the video file being streamed also increases. A high resolution video stream from a single security camera may use up 500kbps or more bandwidth, so it is not hard to imagine a 16 camera surveillance system requiring upwards of 8mbps to stream high quality video over the internet.
Posts Tagged ‘ dual stream’
Some of the newer DVRs on the market offer a feature called either a substream or a dual stream. A sub stream is used for viewing your DVR over the LAN or WAN when the resolution or frame rate of the recorded video is too high for the available bandwidth. For example, if your DVR was recording at 4CIF (or D1) resolution which is 704×480 in realtime (30fps), that would provide you with some exceptional recorded footage that would be both 4 times larger than the average CIF (360×240) recording and in realtime. Unfortunately, in most cases you would not be able to remotely view the video with fluid motion over the internet because there would not be enough available up bandwidth coming from the DVR location. In this case you would benefit from a sub stream that would be set at a lower resolution like CIF (360×240). This would allow you to have a high quality recording, but still be able to view fluid video over the internet.