[EAS] WEA graphics

[Sean Donelan]

On Fri, 16 Jul 2021, Robert Bunge wrote:
> He achieved his goal; at the time, he turned me from an advocate of 
>including a link to a map to a skeptic.

I'm opposed to including a link to a static image.  Wrong answer to 
the wrong question. The over-the-air spectrum is constrained.

On the other hand, the local processing power of smart phones and mobile 
devices has increased.

Essentially every smart phone now includes a built-in map application, 
caches map tiles (parts of a map) of the vicinity as other apps use map 
data and doesn't download the map every time, has GPS and other 
geo-location services for the location of the phone.

Smart phones "know" (most of the time, exceptions apply)

   1. the approximate location of the device itself
   2. the warning polygon area broadcast with the alert
   3. recently used cached map tiles of the vicinity for additional context

Providing warning area location context to the smart phone user doesn't 
require a "link" to retrieve a static graphic from a server.

Unfortunately, Bell Heads often think the network must control the 
devices, and forget smart devices are capble of independent actions.

Broadcasters are going to have to learn the same lesson themselves as 
ATSC 3.0 becomes available, and Smart TVs screens are no longer 
just displays for content controlled solely by the broadcast signal.