Frame rate
Typically, a frame rate of 30 fps is sufficient in sports broadcasting systems. If the camera is unable to clearly capture the ball owing to its speed, a higher frame rate can be chosen. Since resolution and frame rate limit each other at a given bandwidth of the processing platform, it is important to find a balance between the two.
At a resolution of 4K, achieving a frame rate of 30 fps is not challenging given the availability of high-end processors today. At the same time, if you have a limited budget and cannot go with expensive processors, keep a check on the resolution and frame rate. You also need to make sure that the application requirements are not compromised.
Dynamic range
In the case of outdoor games happening during the day, there is a high likelihood of the camera facing bright sunlight. In such scenarios, a camera with high dynamic range (HDR) is recommended. For example, TechNexion’s VCI-AR0821-CB comes with HDR capability and is suitable for use in outdoor settings.
It is based on the AR0821 sensor from onsemi and comes with a unique combination of ultra-high resolution and high dynamic range. A dynamic range of 100 dB or above is recommended for sports broadcasting systems.
Also read: HDR Cameras and Their Applications in Embedded Vision
Multi-camera synchronization
Sports arenas are large and a single camera will not be able to cover a match properly. Hence, a sports broadcasting system has to use multiple cameras to cover the entire field of view. A combination of 4 to 5 cameras is ideal. The number of cameras will primarily depend on the size of the field. You also need to consider parameters like lens distortion and processing power to ensure you get the desired output.
For example, using fewer cameras than necessary can result in lens distortions. On the other hand, using too many will consume more processing power apart from adding to the cost. This is why it is recommended to take the help of an imaging partner like TechNexion before you make a final call on the number of cameras.
Related: Multi-Camera Systems in Embedded Vision: Applications and Features
Ability to withstand outdoor conditions
Apart from dynamic range, you also need to ensure that the camera system is capable of withstanding harsh outdoor conditions. These include dust, rain, fog, snow, etc. To justify the ROI of the installation, the system should offer a minimum life of 5 years. To achieve this, it is recommended to use IP-rated enclosures. For example, TechNexion’s cameras come with an optional IP68 enclosure which protects them from any damage from water or dust.
Long-distance transmission
In most cases, the camera modules are mounted on a pole to ensure broad coverage. Given this, if the processing platform is placed at the bottom closer to the ground, the distance between the two units will be about 2 to 3 meters. This means that the camera should be able to transmit image data that far. Long-distance camera modules like GMSL2 and FPD-Link III cameras are recommended in such scenarios.
Image stitching
When you use multiple cameras to capture a single scene, to get the complete view, you need to stitch images from the cameras together. A 180-degree stitching algorithm has to be designed in order to achieve this.