We are often asked about the concept of "Loop Recording" and how it works, the settings available, what it does and why it may be useful. If you are wondering about this yourself - then please take a few minutes to read our guide and hopefully all will be revealed.
Firstly, car cameras use memory cards to store the video footage they capture. These cards can vary in size (whereby size=capacity in minutes) which means there is a limit on how much video can be present on them (in terms of minutes) at any given point in time. The demands of the car camera owner often dictate that the camera is left recording for journeys which last longer than the number of minutes of video which can be stored on the card present. For example, if the memory card can hold upto 4 hours of video, but the car journey is 5 hours long, then we have a deficiency of 1 hours worth of memory for that particular journey.
It should be noted at this point that this is only a problem for the owner if a video of the ENTIRE journey from point a to point b is required for storage and review at a later stage. For example, a training instructor for a long distance lorry driver may need to record a 5 hour journey, and also be able to play back the footage from the point the driver entered the cabin, until the engine was turned off at the destination 5 hours later. These circumstances are fairly rare, and can be catered for with large capacity video cards and lower video quality settings (so long as the quality remains above reasonable and useful limits).
For the vast majority of car camera users however, the ONLY part of a journey they are interested in is the part where an incident occurs, and typically, an incident or accident only takes seconds of video - rather than hours!
With this in mind, the makers of car cameras have implemented "Loop Recording" which allows the owner of the vehicle who is not concerned with storing hours of footage simultaneously, to use a memory card with a relatively small capacity, safe in the knowledge that at the expense of uneventful footage, the footage which contains an accident or incident will be safely stored even if the memory card becomes full.
How does loop recording work on an in-car camera?
The basic process assumes that the "oldest video footage" present on a memory card is of no use, and can therefore be deleted if the memory card becomes full. In order to do this, there are normally various loop recording options present on the cameras settings menu, which define exactly how much (in terms of minutes) of the total video can be deleted when more space is required as a journey continues.
Deleting a portion of a single video file is extremely processing intensive, and could not realistically be performed whilst the camera carries on recording, so the camera will create small video files of a length which is determined by the settings. For example, if the setting for loop recording is "1 Minute", then the camera will create video clips of 1 minute in length - and a 1 minute clip will be deleted when the the camera needs more memory. If the setting is "5 Minute", the the camera will create video clips of 5 minutes in length, and a 5 minute clip will be deleted when the camera needs more memory.
The picture below shows a memory card which is - for the purpose of this document - full.