A.2 "See what I see" use case

22.4683GPPGroup Communication System Enablers (GCSE)Release 17TS

A.2.1 Description

This use case illustrates a situation where a policeman shares multimedia content (video and/or picture) with all the members of a pre-defined group (including the dispatcher and group members in the field). According to the operational rules of the users, the sharing of multimedia content within a group might be authorized by a dispatcher or not. This use case describes the case where the sharing is authorized by the dispatcher.

A.2.2 Actors

A group of police officers is affected to a mission of protecting a touristic and shopping area from pickpockets and delinquency acts.

Officer Graham is the dispatcher in the control room.

Officer Smith and Johnson are two members of the team on the field.

Officer Smith is assigned to the surveillance of the main square of the touristic and shopping area. Officer Johnson is another member of the group assigned to the surveillance of a set of streets adjacent to the main square of the area.

A.2.3 Pre-conditions

A group "Area Protection Team" is created to provide multimedia communications between the officers in the field and the incident management officer in the control room.

All officers (including Officers Graham, Smith and Johnson) have their equipment configured to the "Area Protection Team" group.

Officer Smith is equipped with a wearable camera connected to his UE. Officer Smith’s terminal is also capable of multimedia communications (video, voice group calls, text and data). All members of the group in the field have the same equipment set-up.

Default communication mode is Push to Talk (PTT) voice [refer to A.1 "Speech Group Call Use Case and requirement proposal"].

A.2.4 Service flows

1- Officer Smith is supervising the main square of the touristic and shopping area. He is in voice group call communications with all members of the team on the "Area Protection Team" group.

2- Suddenly, a pick-pocket steals a camera from a tourist in the vicinity of the Officer Smith. Officer Smith informs the team (including the dispatcher) using PTT voice communication that an incident is occurring in the main square.

3- Officer Smith identifies the suspect in the crowd. He activates the transmission of his wearable live video camera. A live video communication is created between Officer Smith’s UE and the control room. Officer Graham can also see the suspect on the live video. Optionally, Officer Smith receives an indication that Officer Graham is actually receiving the live video flow.

3bis- Optionally, Officer Graham remotely triggers a modification of the quality of the live video to a higher quality.

4 – Officer Graham dispatches the video to the other members of the team so that all of them can identify how the suspect looks like (note, suspect identification can be augmented by means of voice description using the PTT communications on the "Area Protection Team" and/or by highlighting and tracking the image of the suspect on the live video). A video group communication is then created from the network to all team members. All team members can now see what Officer Smith is seeing and can also identify the suspect in the crowd.

5 – From the live video that Officer Johnson receives on his terminals, he realises that the suspect is running into his direction. He gets ready to arrest the suspect.

6 – Officer Johnson arrests the suspect.

A.2.5 Post-condition

After the suspect has been arrested, Officer Graham suspends the sharing of the video with all group members.

Officer Smith stops transmitting live video images.

Communications between all members of the team reverts to nominal PTT voice communication.