Bandwidth is one of the most fundamental, complex and overlooked aspects of video surveillance.
Many simply assume it is a linear function of resolution and frame rate. Not only is that wrong, it misses a number of other critical elements and failing to consider these issues could result in overloaded networks or shorter storage duration than expected.
In this guide side, we take a look at these factors, broken down into fundamental topics common between cameras, and practical performance/field issues which vary depending on camera performance, install location, and more.
Resolution: Does doubling pixels double bandwidth?
- Framerate: Is 30 FPS triple the bandwidth of 10 FPS?
Compression: How do compression levels impact bandwidth?
CODEC: How does CODEC choice impact bandwidth?
Smart CODECs: How do these new technologies impact bandwidth?
Practical Performance/Field Issues
- Scene complexity: How much do objects in the FOV impact bitrate?
- Field of view: Do wider views mean more bandwidth?
Low light: How do low lux levels impact bandwidth?
WDR: Is bitrate higher with WDR on or off?
Sharpness: How does this oft-forgotten setting impact bitrate?
Color: How much does color impact bandwidth?
Manufacturer model performance: Same manufacturer, same resolution, same FPS. Same bitrate?
The most basic commonly missed element is scene complexity. Contrast the 'simple' indoor room to the 'complex' parking lot:
Even if everything else is equal (same camera, same settings), the 'complex' parking lot routinely requires 300%+ more bandwidth than the 'simple' indoor room because there is more activity and more details. Additionally, scene complexity may change by time of day, season of the year, weather, and other factors, making it even more difficult to fairly assess.
We look at this issue in our Advanced Camera Bandwidth Test.
Inside, we cover the 10+ other issues listed above.
[[Note: this guide was originally released in 2014, but has been restructured and updated with additional information, including Smart CODECs and H.265]]