What type of cameras is classified under the category 3-4?

Fixed dome cameras are classified under the category 3-4 primarily due to their design and functionality that suit a wide range of surveillance applications, especially in environments where aesthetics and unobtrusiveness are important. These cameras typically feature a dome-shaped enclosure that can be mounted on ceilings or walls, making them less visible and less prone to tampering than other camera types.

Category 3-4 emphasizes cameras that provide adequate performance for indoor or outdoor applications while balancing factors like resolution, coverage area, and mounting flexibility. Fixed dome cameras generally offer good image quality and can be equipped with various lenses to cater to different surveillance needs, making them versatile options in both residential and commercial settings.

In contrast, the other camera types listed have distinct functionalities or design purposes that do not align with the category classification. PTZ cameras, for instance, are known for their pan-tilt-zoom capabilities, allowing for extensive coverage but are classified differently due to their operational complexity. Meanwhile, encoders and decoders are not cameras but rather devices used for video transmission and compression. Live streaming cameras focus on broadcasting rather than local recording or monitoring, and thus fall into a different category based on their primary function.