These days, you can spend a lot of money buying really nice digital signage tools. And if you’re doing so, then you likely have some pretty dynamic content you’d like to load. Something that doesn’t necessarily lend itself to a dynamic content platform, but which is nice for the quick presentation that you whip up and want to use for a form of digital signage is Keynote presentations. These are inexpensive and can be played on monitors through AirPlay or directly through a Mac Mini connected to a television or big monitor. Great for a monitor in the company lobby, the hallway in the school or for subliminal messaging at the DMV to convince you that no, the guy with the forehead tat isn’t really going to shank you (srsly, metal detectors, pls).
There are a few issues there, though. First, for most uses, you need the presentation to either go on forever or need to queue up a bunch of them. Then, you need to set the presentation to automatically start when opened so that you can just open files through a script. Scripts being able to be set as login items for a default user. There are also some logistical issues with the physical hardware if it’s in public, but I’ll assume you’ve got those covered and move on to the technical details of how to do the above tasks.
To prepare a Keynote presentation, first open the Keynote, click on Inspector in the toolbar and then at the inspector click on the document icon (in the far left top corner of the inspector). Then, check the boxes for “Automatically play upon open” and “Loop slideshow”. This will automatically play the presentation and start it again when it’s done.
Then, the entire Keynote is automated. That part is all done within Keynote and the next part is just opening and closing Keynote from the command line. To open via ARD or another management tool, send the following command:
Then to close Keynote and run something else:
To close one presentation and immediately reopen a different presentation, merge the commands into one line:
killall Keynote; open /Users/admin/Desktop/Presentationname.key
Just make sure everything’s automated or the loop won’t run. Now, to automate events within Keynote will require clicking on things from an AppleScript or Automator workflow or using the AppleScript options for Keynote. To automate just clicking to move to another slide can be done with the following AppleScript (and sent via osascript), although it’s usually best done within Keynote:
tell application “System Events”
The following are all of the Keynote-specific options from Automator:
To close a single presentation, the following workflow would do the trick:
One challenge is that when you loop through different Keynote presentations, you would see the desktop of OS X and the Dock while Keynote is re-opening if you kill it off first. It should take a little less than a second. Once keynote re-opens, you see the menu for keynote for about another half second while the keynote document is opening. If I don’t close Keynote and instead just open a 2nd document then I see the Keynote menu bar for a split second while the second presentation is starting and I don’t end up seeing the actual Desktop. That would be done just by opening a second presentation from the command line. The caveat is that as you toggle between them, if you don’t kill off the Keynote application, you’ll end up starting where the other left off rather than at the beginning (which might be fine in a given workflow).
You can, if you need to kill the application, launch the screen saver first:
osascript -e 'tell application id "com.apple.ScreenSaver.Engine" to launch'
Or just in bash:
open -a /System/Library/Frameworks/ScreenSaver.framework//Versions/A/Resources/ScreenSaverEngine.app
This just fires up the screen saver to try and hide what you’re doing in the background. You can layer the three commands we’ve looked at on top of each other as a single command from ARD:
osascript -e 'tell application id "com.apple.ScreenSaver.Engine" to launch' ; killall Keynote ; open /Users/admin/Desktop/Presentationname.key
That would effectively kick off the screen saver, kill keynote while it’s hidden and then open the new presentation. The presentation would need to be transferred to the client system first, but that’s usually the easy part. You could also sleep the commands to bring up different presentations and bolt more logic in, although much of that is best left inside of Keynote itself. If you wanted to get extra crafty, in case the desktop did ever appear, you could have a fail safe of having the screen saver appear as the desktop background, which I wrote up awhile ago here. There are also various kiosk applications that do crazy things like replace the Finder or fire up kioskish (is that a word?!?!) browsers and the such, but all will likely require a little testing and massaging to get just right.
Overall, Apple products can make for pretty good signage options given how well they typically handle various graphics and connectivity, without buying 3rd party tools. You do get what you pay for, so it might be worth looking at some of those tools. Also, it’s worth noting that Rich Trouton wrote up a nice article on using AppleTV for this type of stuff here on his site. I’ve also scripted digital content delivery to Macs using Final Cut Server, CatDV and various scripting tools such as python. We’ve even gone so far as to programatically create the actual Keynote files, but that’s probably best saved for a github gist rather than a krypted.com post…