How Video Motion Detection (VMD) Works
Video Motion Detection (VMD) in the TELUS SmartHome cameras is the camera’s ability to trigger recordings based on any detected motion. The camera identifies motion by measuring how the video’s pixels change from one moment to the next. It can be an effective way to capture activity and generate notifications for the customer. When editing Video Motion Detection windows identify your main areas of concern and draw narrow windows near those areas. For example, if there is a jewelry box on the desk, make sure to draw a VMD box either around, or along the path leading up to that area.
Drawing VMD Windows
What to avoid In VMD windows
Some movement or pixel changes will cause false triggers. It is best to avoid these as much as possible:
- Trees, foliage or any type of fabric that the wind or an air vent may blow should be avoided.
- Any windows that are not a security concern. When the sun rises and sets, these may cause false triggers.
- Any areas with numerous shadows, such as a window that people (not of concern) walk past or with shading from trees. Remember to think about how the lighting may change throughout the day; an area that was not shaded may become shaded later in the day.
- Always be sure to use all 3 VMD windows instead of just one large VMD window. The smaller the box, the less prone to false-triggers the recordings will be.
What if I want the entire camera view to trigger a recording?
Rather than creating one large box that will not be precise, try creating lines or "barriers". The goal is to catch a person of interest as they cross through the window.
You will notice that we:
- Avoided the room’s windows due to sunlight changes.
- Created VMD windows as barriers that must be crossed when entering the area.
- Created a VMD window that must be crossed when going through the room.
- Used all 3 VMD windows.
- Kept all 3 VMD windows as small/skinny as possible.
Selecting Target Size and Sensitivity
Target size is what percentage of the window must have movement in it to trigger a clip. Too large of a target size and the camera may not trigger for anything less than an object the size of a car.
Too small of a target size and leaves blowing in the wind may trigger recordings. You need to find the happy medium.
What percentage should I pick?
A great rule of thumb is to estimate the percentage of a window that a person would fill (if that fits the request) and then select one size larger. For example, in the image above, if one of the chairs was the same size as a person, that person would take up about 15% of the window. Therefore, when selecting the target size, we should select 20%. That percentage would pick up a person, but will most likely not pick up any stray shadows.
What is Sensitivity?
Sensitivity is a measure of how drastic a change is needed to trigger a clip. Higher sensitivity means a smaller shift in the video is needed to trigger a clip. But too high of a sensitivity and the camera may trigger constantly.
What level is the best?
Typically you should start with a sensitivity of 7 and fine-tune from there. If the sensitivity needs to be maxed at 10 then your window placement, size, and target size most likely need to be adjusted.