1. A cloud-based surveillance system for a target surveillance area, comprising: at least two input capture devices (ICDs) and a cloud-based analytics platform; wherein the cloud-based analytics platform is constructed and configured in network-based communication with the at least two ICDs; wherein each of the at least two ICDs has at least one visual sensor and is operable to capture and transmit input data to the cloud-based analytics platform; wherein the cloud-based analytics platform is operable to: generate 3-Dimensional (3D) visual data based on 2-Dimensional (2D) visual data captured from the at least two ICDs; and perform 3D analytics based on the 3D visual data and the input data.