How Does Emergency Video and Announcement Messaging Work

[Edward.P]

How can I set up my DMB player to support emergency video broadcasts or unplanned "announcement" messages across my network of A140 STBs? Does the Digital Media Bridge player on Amino STBs support this kind of thing?

[Cilutions Support]

There are three ways to issue alert messaging or real-time content to the STBs. The first two supporting multicasting to a set of STBs, the third supports unicasting to individual STBs:

Configuring an alert_watch asset inside a screen: Here the player, while it is rendering its normal screen in the foreground (i.e., regular programming visible to the user), will silently listen for an IPMC:Port video stream in the background. When the video stream goes active the player will jump to the target alert screen. It will stay on the alert screen as long as the video stream is active. After the video stream goes inactive the player will return to the original, interrupted, screen and start the original screen over from the beginning. Typical application use: emergency video broadcast. It can also be used to support non-emergency, ad hoc, video events (like an unplanned campus-wide press conference). The active video source on a well-known IPMC:Port address is the triggering mechanism. Note that the video format must be supported by the STB (e.g., h.264 transport stream).

Configuring an overlay asset inside a screen: Here the player will silently listen for an IPMC:Port command (not a video stream). The command can contain up to 6 lines of text to display and the number of seconds to leave it active. When this command arrives the player will overlay the current screen with an overlay screen layout, rather than jumping to a new screen. The overlay screen can cover some or all of the currently playing screen. So, for example, you can just display the overlay messaging across the top of the screen and leave the bottom portion still showing its current asset(s). The overlay screen will remain visible for the configured number of seconds in the command received. Note that all assets except video (e.g., scrolling text, RSS, scrolling epg_grid) will suspend, and not advance, while the overlay screen is visible. Typical application use: paging or periodic messaging system. Here an external application is the triggering mechanism. This application determines when to issue the message, how long to leave it up, and when to stop paging.

Issue a full on-demand screenlist with assets embedded in the command: This is a unicast method where an external server makes a TCP connection to a STB and issues a full screenlist with some assets (e.g., a image file, text) to display. The STB will immediately stop what it is doing and respond to the new command and screenlist. Typical application use: real-time display system. Here a real-time external application builds images and text for display and issues them to an STB in real-time fashion. The full screen lists and their assets are received and displayed in milliseconds. It offers a highly flexible and very responsive display mechanism.

Note that these features are not mutually exclusive so all three can be employed on a network of STBs operating independently in response to external triggering events; emergency video, paging or real-time display commands.

[Cilutions Support]

The Screen Builder contains an application useful for sending announcement messages to one or more STBs in a real-time fashion. It is installed as "...DMB Screen Builder\paging.exe". When started with no command line parameters it runs in graphical mode. Command line usage is as follows:

paging.exe <DestIP> <DestPort> <Timeout> <Param1> ... [Param6]

where:

DestIP: The Unicast IP Address associated with a particular STB or the Multicast IP Address associated with a group of STBs

DestPort: The Port on the STB(s)

Timeout: The number of seconds to display the announcement message

Param1: The text string to display - associated with parameter 1. There can be up to 6 parameters

examples:

Send 2 parameters to a single STB to display for 5 seconds: paging 192.168.1.15 3333 5 "unicast hello" world

Send 3 parameters to a group of STBs to display for 10 seconds: paging 228.7.6.5 1234 10 "multicast hello" small world

The screenlist running on each target STB must contain one or more Overlay assets tuned to the paging address (e.g., port 3333 for unicast) to be able to catch and process these announcement messages.

Lastly, a screenlist can contain both unicast and multicast overlay assets thereby offering the ability to process an individual paging announcement, targeted to a single STB, or a group paging announcement, sent to two or more STBs for simultaneous display.