How to choose between high definition and standard definition CCTV cameras for vehicle safety
Vehicle CCTV has grown in popularity over the last few years with many fleet operators choosing to equip their vehicles with the technology to improve safety, support driver training and prevent fraudulent claims.
For fleet operators considering investing in commercial vehicle CCTV, understanding the benefits of each system and what is most appropriate could save money in the long term. Warren DiMarco from Brigade Electronics Canada explains the differences between high definition and standard cameras.
High definition versus standard definition vehicle CCTV
The main difference between high definition (HD) and standard definition (SD) is the number of pixels contained in the displayed image. HD images have more pixels per square inch compared to SD, meaning a HD system will provide much clearer pictures with finer details. Typically, HD is referred to as a 720p and above.
Ultimately, HD will provide more clarity and detail, allowing drivers to see an object or person in a vehicle's blind spot with ease so they can act quickly to prevent a collision.
HD formats - analogue versus digital
The HD system is available in two different formats - analogue or digital. This refers to the method in which footage is recorded and delivered.
Analogue cameras capture images and send the signal over coaxial cables to a recorder or ECU (electronic control unit). These images are then converted from an analogue format into digital signals, compressed and then stored on a hard drive or shown in real time on a monitor.
Digital cameras or IP cameras (internet protocol cameras) capture images digitally from the outset. These cameras send data over a computer network rather than via a recorder or ECU first.
Which format is best for my vehicle?
IP cameras offer high-definition footage via a digital camera with its own IP address. Instead of transmitting video over a video cable to a monitor, the IP cameras transmit via a data connection where images are safely stored to the HDD memory. This means they can be connected easily to expansion modules using Power Over Network (PON) without the need to invest in expensive additional equipment.
Due to video latency (effectively a time lag for footage appearing on screen) IP cameras should not be relied on as an aid for manoeuvring or blind spot monitoring. However, IP cameras are an excellent choice for general monitoring of vehicles, such as ensuring passengers are safely seated on buses, and doors are not obstructed before a vehicle pulls away.
Analogue HD cameras on the other hand have no video latency making them ideal for providing drivers with a clear view in real-time. This also means that on-screen display menus are supported, offering a better user experience during operation. Analogue HD technology can transmit video over traditional cabling across distances of up to 500 metres - plenty of cable length for any commercial vehicle.
Do I need a certain monitor to see HD footage?
To view HD footage, you will require a HD compatible monitor. Monitors that only support SD footage can still display images from a HD camera, but without the benefits of the clarity that HD offers. For example, if the image is a HD quality of 1080p, but the monitor can only display 480 pixels per square inch, you will still only receive a SD image.