Security & Surveillance Cameras
Timelapse cameras are essentially dumb cameras connected to a recording device. They take a snapshot picture at a regular interval and store it. Typically, these are used in shops, garage forecourts, etc. How long the footage is kept for depends upon the recording mechanism but, solid state recorders tend to cycle through the storage space over time, automatically deleting older footage.
The market is full of security camera and recording systems. They are split into to main types; analaogue or digital. Generally, the industry is moving to digital cameras because of the flexibility of storage. The digital video camera sapce can also be split into two main types; USB cameras and netcams.
Typically a webcam has a USB interface but, some people use the term to also include netcams.
Netcams (sometimes called livecams) feature an in-built processor and IP network interface. They often feature some in-built intelligence to perform tasks such as motion detection and alerting. We use them in our home (mainly AXIS models). These devices can use a lot of up-link bandwidth, as each one is sending one or more (depends on how many clients are connected) video streams out of your home. This works very well on our FTTP Internet connection but has limited performance over a typical ADSL connection.
These are covered in more detail on our IP network camera page.
Video Activity Monitoring
These systems go beyond simple video capture and use hardware or software to monitor the output from one or more digital video cameras and process the video signals, to decide if activity or movement has occurred. This process is called 'visual analytics' and is then used to determine which time periods are recorded and stored. In more complex systems behaviour can be inferred and used to trigger events or alarms. This can include things like people or vehicle counting, intrusion detection, left objects or object removal.
In the simpler home security system, this process can reduce the amount of video storage required by not to recording or storing the video when in periods of no activity. This makes reviewing and analysis of captured video a much less time consuming process.