White Paper: Challenges face video, digital signage security and alert displays

Posted by ChyTv Admin
March 24, 2016


Challenges Facing Video and Digital Signage Security and Alert Displays

Do you have an existing video distribution system that you need to add security and alert graphics and information to?  Do you have a digital sign age infrastructure and need to interrupt it for alert or mass notification purposes?  In light of escalating terror threats and their increased sophistication, heightened information awareness is required. Offices, schools, campuses, military facilities and any other building or area require instruction during emergencies. It is no longer enough to sound an alarm that means “something is happening”. People must be informed of what is happening and what to do. But there is rarely budget available to tear out an existing infrastructure and start from scratch. Effective security and mass notification often must be added to and integrated with the existing infrastructures. These scenarios pose certain challenges that must be considered, including:

  • What is the video distribution format?  NTSC, PAL, HDMI, HD-SDI, IP, etc.
  • Do you have live video (i.e. set - top - box, cameras, etc.)?  What do you want to do with it? Squeeze it and add graphics around it, overlay graphics on top of it, or replace it with full screen graphics?
  • What is the nature of the Alert? Weather advisories? Industrial Accidents? Homeland Security? Military Action? Missing Persons? Some or all of the above?
  • Who is authorized to “trigger” an Alert? What is their interface? 
  • Who is creating the graphics or templates and what tools are available?
  • What level of quality of the graphics and text is required? Very basic text or broadcast quality graphics with crawls and animations?
  • Does the Alert display system need to retrieve external information? RSS feeds, Website info, XML, Excel, HTML, etc.
  • Does the Alert display system need to be driven by other systems?  Fire alarms, Public Address systems, Crestron, GPI contact closure, RS-232 serial control, etc.
  • Reliability and Support? Do the companies you’re working with have experience and a history of the involved technologies? How well will they support you?
Video Distribution Format
Every facility is different. There are different flavors of video distribution, different flavors of digital signage distribution and different flavors of networking. Every situation has its own unique set of challenges. Are you still SD distribution? Are you HD distribution? Are you SD looking to upgrade to HD someday?

Many existing infrastructures are still analog NTSC or PAL distribution over coax or other. Pulling old cable and running new cable and replacing screens can be prohibitively expensive. Certainly, the older NTSC and PAL video formats that have been in place for a half century are easy and understood; there’s one cable with a known format and connector that every different piece of equipment in the infrastructure knows and speaks.  

HD changes all that. There are different resolutions, including 720p, 1080i and even 4K, different cables, different connectors, HDCP and various other challenges.

There are several choices. Native SD only systems will be less expensive. They will also be more “video centric” in that they will handle NTSC or PAL video directly. They’re video-based as opposed to computer-
based.  But they will have a limited lifespan as time marches on and everything becomes HD. However, in many current infrastructures that may still be a long time away.

Another choice would be to invest in alert display systems that support SD and are upgradeable and / or switchable to HD. Your initial investment up front may be little more, however the switchover to HD would be
more seamless and perhaps more cost effective.

HD-SDI is the most prevalent high-end video distribution that’s not IP based. It is generally used in broadcast and cable head-end environments. It is a well-known and high-quality format and the equipment to support it will be commensurately priced. However, you would have the ability to “squeeze” or “overlay” live HD video with real-time Alert graphics and information.

Live Video
Adding graphics to live video is very challenging.  Live video can be a television channel from a cable or satellite set-top-box, security or monitoring camera feeds, town meeting feeds, House of Worship feeds, campus channels or a variety of other sources. Regardless of whether the input source is SD or HD, adding graphics to a live signal requires having some sort of video capture card or device that can be somehow combined with the graphic content.  

A lower cost USB analog NTSC external capture device is sometimes used. However the resulting live video window is generally a separate static overlay on top of the graphics and allows no dynamic control of
the size or positioning of the window.  In other words, it’s always pinned sitting on top in the same size and position.

Higher end HD graphics capture is more expensive. However with a professional quality capture card, the live HD video can be integrated into the content itself. For example, a live video window can be “squeezed” to any size and resolution and positioned in different locations on different “pages” of the content.  Or, the window can be a “layer” with graphics both in front and behind it. Or, the live video can be full screen (i.e. full resolution) with graphics such as lower thirds, crawls, bugs (i.e. logos) overlaid on top. In addition, the graphics can have a level of transparency (i.e. alpha channel) that allows the overlaid live video in the background to slightly show through.  There is more flexibility in a higher end integrated capture card for varying resolutions as well as support for multiple formats including analog HD, digital HD over HDMI
and HD-SDI over BNC coaxial cable.

Types of Alerts
Older traditional alert systems such as fire alarms, store alarms, etc. may set off loud sirens and flashing lights to let you know that “something” is happening, but they don’t give you any information regarding what is actually happening or what to do. “Mass Notification” is the process of not just raising an alarm, but giving people meaningful information and instructions regarding the emergency. Fire, Weather advisories, Industrial Accidents, Homeland Security, Military Action, Missing Persons, and more are examples of the myriad of possible events that require notification, information and instruction. Along with informational distribution methods such as text messaging, email, strobe lights and audible announcements, digital signage represents an additional mechanism to inform the public during emergency situations.

To address these needs, the alert display systems needs to be able to dynamically, in real-time, interrupt whatever is currently displaying and replace it with appropriate emergency messaging. In addition, after the emergency is over, the display needs to be restored back to its original condition.

Taking it a step further, the emergency alerts themselves need to be relevant to the alert at hand, and in real-time, be able to convey appropriate action to the viewer. For example, an alert message that says “Exit the building using the rear stairway. Avoid the front stairway.” is more informative than “Please exit the building.” This implies both the ability for the emergency alert to not only interrupt the active display with
relevant alert pages, but that the page has the ability, in real-time, to display dynamic text information in a clear, readable format. In addition, the text information will be delivered remotely across a wired or wireless network from some external source that may or may not be nearby the alert display player.

Also, along with the visual Alert display, it may be desirable to have audio cues. It can be as simple as generating some tone or alarm to draw attention, but an effective Alert systems should have the ability to attach audio to the alert message.

Who and How Are Alerts Triggered
Every situation is different. The digital signage may be in a restaurant, mall, government building, corporate building, military base and more. It can also be PEG channel, local government, campus, worship, and other television broadcast channel distributions.  

The roles of the personnel authorized to issue an Alert varies greatly in these situations. In fact, in most cases, particularly larger installations, it is likely that the personnel authorized to initiate an Alert are not at all the same people who are managing the normal daily digital signage and are unlikely to be familiar with the digital signage tools and interfaces.

In these cases, it is desirable to have a system capable of managing the day to day digital signage through an interface appropriate for that purpose, yet also allow for that digital signage to be interrupted through some different “Alerting” interface. This Alerting interface should permit a credentialed Login process whereby only certain authorities are permitted to access and generate Alerts. This interface should be simple and predefined whereby the various possible Alert pages are easily selectable. In addition, some number of dynamic text fields should enable the authority to enter real-time information and instructions.

Content Graphics Creation
In many cases, the personnel authorized to initiate an Alert have no knowledge of the underlying digital signage system or its workings.  Someone needs to be the expert on the digital signage system including its architecture, scheduling, content authoring, triggering interfaces and a variety of functions. This person may be trained as a graphic artist, a system integrator, a station engineer or any other number of jobs.  

A good digital signage system should be easy to use. This means the tools for creating content, scheduling it, and delivering it to the players needs to be intuitive, robust and simple. There should also be available a set of samples and templates for different scenarios that can be repurposed for a given situation. Page layout tools should be WYSIWYG and content management tools should not require knowledge of any underlying technologies such as HTML, XML, network protocols, etc.

Output Quality and Features
You get what you pay for.  There is an ever growing array of digital signage players and systems ranging from $50 jpeg players to $1,000 HD players to $15,000 HD-SDI graphic generators to full enterprise systems costing hundreds of thousands of dollars. What does your situation and infrastructure require, and at what level of quality? Most of the lower cost digital signage systems allow the scheduling and playout of images and videos. However they often lack features needed for effective real-time Alert notification. This includes at a minimum the ability to interrupt the playing schedule to display an Alert message and the
ability to display dynamic informational text that is clearly legible.

Higher end systems will give you more flexibility and higher quality look and feel. In addition to SD formats in and out, a higher end system may support digital HD over HDMI, HD Component and HD-SDI in and out with graphic overlay on top of live video. Additionally, full screen graphics can be displayed with dynamic text, logos and animations. A versatile play-list scheduler allows for dynamic programming and smooth, elegant page transitions. The user interface allows for direct control of a single or multiple Alert systems. Professional Crawl overlays are broadcast quality, smooth and easily modified. Multiple Crawls can display
simultaneously and can include graphics and logos. Also, HD clip playout with graphics overlaid and layered.  A quality high end digital signage and alert system will include many or all of these features.

External Data and Interfaces
It may be desirable for your Alert system to be triggered by some other external system such as a fire alarm or audible PA (Public Address) system. Or it may be desirable to collect and display information from an external source such as a remote Web or desktop interface, RSS feed, XML, database or even just a simple ASCII text file. A good Security and Alert system will offer a variety of methods for external triggering and collecting external information whether by hardware, software or both.

Hardware triggering can include traditional methods such as GPI (General Purpose Interface) or RS-232. GPI is a simple “contact closure” signal on a particular pin which can invoke a predefined ‘macro’ sequence of page displays. Like GPI, RS-232 control is also a hard-wired connection. However RS-232 commands can deliver more varied and flexible instructions along with dynamic data. An externally controllable Alert system may have an API (Application Programming Interface) and SDK (Software Developer Kit) to enable very specific or even custom control of the Alert messaging and information. Often, the same commands can be delivered either via RS-232 or IP network socket connection.  

Many fire alarm systems, public address systems, EAS (Emergency Alert System) and automation systems have the ability to generate these external triggers. For example, Bosch Praesideo is a leading public address and emergency voice evacuation system. When an audible alert is generated, a corresponding command can be issued to a ChyTV digital signage device to display a relevant visual message. Another example would be a Crestron automation system programmed to tell a ChyTV digital signage device to display specific pages and graphics and dynamic text. Hardware control via GPI and RS-232 can range from a simple push-button to enterprise level custom programming and interfaces using the digital signage device simply as a reactive player.

Software driven alerts can be achieved through a variety of methods as well. Provided the digital signage system supports an external command protocol, any interface implementation is possible. The question goes back, to what are the requirements?  Who is authorized to “trigger” an Alert?  What is their interface? Who is creating the graphics or templates and what tools are available? It may be desirable to have a dedicated, simplified interface unrelated to the day to day digital signage tools that has the ability to interrupt the schedule with the alert. The interface can be Web based in the Cloud, or it can be a desktop application speaking directly via IP socket or a number of different network protocols. Or the digital signage device may be able reach out at regular intervals to an external source of the Alert and corresponding information.

For example, in the PEG Channel (Public, Education, Government) field, smaller budget local television stations are operated by a limited staff. Often scheduled or automation driven “bulletin board” graphic systems are used to cycle through public announcements and such. In an emergency situation, there may be no operator available at the studio to display the Alert. In use at a number of such stations, a ChyTV HD Alert system gives the station manager the ability to trigger and alert and “crawl” relevant information overlaid on top of the existing channel by updating an ASCII text file from something as simple as Notepad.  The HD Alert lets you pass through your normal programming while monitoring for external text-file based emergency information. If a designated text file shows up in a ‘watched’ folder, the ChyTV HD Alert
system grabs the text information from the file, displays an appropriate overlay graphic on top of the live programming, and displays the text information in the file using high quality broadcast effects such as crawls, pushes, fades, etc. When the text file goes away, the alert message goes away. The alert can easily be generated remotely by any authority and requires no graphics or operational skill or training.

Reliability and Support
How long has the manufacturer been around?  What are their credentials and expertise?  How accessible are their experts?  Is Customer Support knowledgeable about the products and willing to spend time supporting it, or is it an off-shore calling center? An effective Alert system is likely to be somewhat custom and perhaps complex. Canned off the shelf solutions generally won’t handle real-time Alerts in a timely and effective fashion. Does the company have the expertise necessary to help with custom solutions and unique problems?  Will you have access to those people?  Have they integrated systems in these situations before?  Is custom engineering possible to add new features or modify program behavior?

Be Prepared
It seems the world has become smaller and more threatened over the years and that doesn’t appear to be improving.  Security, Alerts and Mass Notification are becoming more necessary than ever. To truly address Alert notifications from a visual aspect, the alert display system must be reliable, flexible and capable of displaying real-time, relevant information in an easily readable format. Are your formats supported?  Is live video (TV, camera, etc.) a requirement?  What is the nature of your Alerts, and who is authorized to trigger them?  What external controls and remote information are required? Don’t think in terms of alert products. Think in terms a complete Alert Solutions.

The ChyTV product line from Digit Signage Technologies has a long history of successful and reliable installations in a variety of facilities, including Capitol Hill, military bases, Navy ships, college and university campuses, PEG channels and more. Experience matters.