Why info-beamer pi is awesome

This is a Raspberry PI

By default it doesn't do much: You start it and you'll end up in a desktop environment. That's fine, but to turn it into a digital signage display you'll need some additonal software.

Introducing info-beamer pi

info-beamer pi is a software created for the Raspberry PI. It is available on the download page. info-beamer itself is a small but powerful tool. So the download is tiny compared to other programs.

Installation is very simple on Raspbian as all required dependencies are readily available. A quick overview on how to install it can be found on its page and in the README file in the download.


      pi:~$ wget https://info-beamer.com/jump/download/...

      100%[========================================]

      pi:~$ tar xf info-beamer-pi.tgz

      The file gets unpacked

      pi:~$ cd info-beamer-pi

      pi:~/info-beamer-pi$ ls -l

      -rw-rw-r-- CHANGELOG.txt

      -rwxrwxr-x info-beamer

      -rw-rw-r-- LICENSE.txt

      -rw-rw-r-- README.txt

      drwxr-xr-x samples

      pi:~/info-beamer-pi$ _

      
        You can find the exact installation instructions
        here.

info-beamer is a programmable visualization framework

You are not limited to a predefined set of visualizations. Instead info-beamer provides an easy way to build almost any kind of visualization you can imagine.

All you need to do is write some code. Don't worry, info-beamer makes that quite easy.

Of course there is example code and documentation available to help you get started.

How info-beamer code looks like

info-beamer uses the Lua programming language. You've probably used some software or website powered by Lua it without even noticing it. Don't worry if you've never heard of it, because learning Lua is really easy as it's a small and simple language.

The code you see here is all you need to write Hello World on the screen. Just save that code in a file called node.lua, place the font file silkscreen.ttf next to it and then run info-beamer.


      gl.setup(1024, 768)

      

      local font = resource.load_font "silkscreen.ttf"

      

      function node.render()

        font:write(120, 320, "Hello World", 100, 1,1,1,1)

      end

      
        This code is included in the info-beamer download in samples/hello.


      pi:~/hello$ ls -l

      -rw-rw-r-- node.lua

      -rw-rw-r-- silkscreen.ttf

      pi:~/hello$ info-beamer .

      The visualization is running. Press Ctrl-C to stop it.

      pi:~/hello$ _

info-beamer can load different file formats

Of course you cannot only load font files, as seen in the previous examples. You can also load images (jpeg and png) as well as video files in the mp4/h264 format.

Loading assets is done with just a single line of code. info-beamer does all the heavy lifting of setting up hardware decoders for/video playback.

If you have other files, like flash content, gifs or Powerpoint files, you have to convert them to mp4 files and then just handle them as video content.


      local image = resource.load_image "lenna.jpg"

      local video = resource.load_video "hamster.mp4"

Let's animate things

info-beamer is optimized for smooth output. The goal is to have a 60 frames per second output without stuttering or jittering. Of course that would be boring if there is nothing animated on screen.

Animating things works by moving, rotating and scaling the content that is displayed. If you rotate the images of clock hands around the center of an image of a handless clock you already have a working clock. Well, mostly.

The content of the complete screen is redrawn every frame (so 60 times per second!). Each time the return value of the sys.now() call will return a new value based on the current time.


      gl.setup(1024, 1024)

      local hand = resource.load_image "hand.png"

      local clock = resource.load_image "clock.png"

      function draw_hand(angle)

        gl.pushMatrix()

        gl.translate(WIDTH/2, HEIGHT/2) 

        gl.rotate(angle, 0, 0, 1)

        hand:draw(0, -10, 200, 10)

        gl.popMatrix()

      end

      function node.render()

        local time = sys.now()

        local hour = (time / 3600) % 12

        local minute = time % 3600 / 60

        clock:draw(0, 0, WIDTH, HEIGHT)

        draw_hand(360/12 * hour - 90)

        draw_hand(360/60 * minute - 90)

      end

Dynamic content

So far the content is animated but static: It will always display the same clock. Fortunatelly info-beamer makes it easy to create dynamic visualizations.

You can react to changes to local files and immediately load them. For certain use cases there are helper functions that make this incredibly easy.

Want to always show a certain image in the current directory? Just use the function util.resource_loader. It will load one or many resources and keep them updated if the file changes.


      gl.setup(1024, 1024)

      

      util.resource_loader {

        "background.jpg"

      }

      

      function node.render()

        background:draw(0, 0, WIDTH, HEIGHT)

      end

      
        Learn more about
        util.resource_loader.


      pi:~/example$ ls -l

      -rw-rw-r-- node.lua

      -rw-rw-r-- background.jpg

      -rw-rw-r-- another_background.jpg

      Start info-beamer in another terminal, then proceed

      pi:~/example$ mv another_background.jpg background.jpg

      You'll immediately see the new image displayed on screen

      pi:~/example$ _

No wheels reinvented

info-beamer can't load content from, for example, a webserver. But don't worry: Just use an external program to do that, then write a file (for example a JSON file) which info-beamer can pick up. info-beamer will notice file changes immediately and you can update the displayed content.

info-beamers philosophy is do one thing only and do it well. Loading data from a webserver isn't a thing that info-beamer does, so just use for example python combined with the excellent requests module to query web APIs.

So always use the best tool to fetch and prepare the data, then let info-beamer visualize it.


      util.file_watch("external_data.json", function(content)

        twitter_feed = json.decode(content)

      end)

      
        Using
        util.file_watch 
        to keep a variable in sync with a JSON file.

Multiple Channels

info-beamer was designed to be easy to combine with other software. Changing files and letting info-beamer pickup those changes is only one way of communicating. If you have more rapidly changing information you want to send to info-beamer you can also use UDP or TCP based communication.

Sending realtime data of, for example, the total incoming bandwidth usage of some file server to info-beamer can be as simple as running a shell command.


      pi:~$ while true; do

      > RECEIVED=`grep eth0 < /proc/net/dev|awk '{ print $2}'`

      > echo "traffic/received:$RECEIVED" > /dev/udp/localhost/4444

      > sleep 1

      > done

      This command will now send data to info-beamer


      gl.setup(1024, 768)

      local font = resource.load_font "silkscreen.ttf"

      node.alias "traffic"

      util.data_mapper {

        received = function(val)

          received_mb = tonumber(val) / 1024 -- convert to MB

        end

      }

      function node.render()

        font:write(10, 10, string.format("MB received: %d", received_mb), 50, 1,1,1,1)

      end

Rapid development

So far we've seen that info-beamer can load (and reload!) images, videos, fonts and can react to external data received over the network. But info-beamer will also reload the code that is currently running the visualization. This allows live coding.

Providing a visual editor to create content is difficult as info-beamer provides a real programming environment. Live coding makes up for that by giving you instant feedback on changes you make to your code. Just click Save in your editor of choice and you see the result on the screen. There is no need to restart info-beamer: It just works.


      gl.setup(1024, 768)

      

      function node.render()

      
          gl.clear(1,0,0,1)  -- clear screen in red

      
      
          gl.clear(0,1,0,1)  -- clear screen in green

      
      end

      
        Changing the arguments to the 
        gl.clear 
        function is immediately visible once you hit Save in your
        editor.

Why choose info-beamer?

✓ High performance rendering at 60 frame per second

No other program on the PI will reach the same performance while being as simple to use. info-beamer uses the PI to its limits. No browser based solution can archive smoothly scrolling text while smoothly animating transitions of content.

✓ Smooth animation of videos, images and text

There is no other programs for the Raspberry PI that comes close to the features info-beamer offers: Fully animatable videos (you can scale, rotate or move them while they are playing). Fully background loading of resources and exact control over video playback which allows seamless switching between videos.

✓ Dynamic reloading of changed or added resources

info-beamer makes it incredibly easy to build dynamic visualizations that change their content over time. The ability to react to changed files allows you keep your displayed content up-to-date in just a few lines of code. So you never have to check for new images, videos. You will be notified instantly if any file changes, is added or removed. This also makes it easy to deploy updated content to the devices running info-beamer. Often using rsync is more than enough: There is no need to restart info-beamer or even make it aware of updated files - it's all done for you automatically.

✓ Easy integration with existing tools/infrastructure

There is no need for a complete rewrite of all your existing software to use info-beamer. Instead you can use your favourite programming language and tooling to generate data that can be easily consumed by info-beamer. Every software can generate JSON after all. Then use the power of info-beamer to display the data in the best way possible.

✓ Rapid development through live coding

If you have never used any form of live coding before, prepare to be amazed. Seeing changes you make to code instantly will change how you approach development of software: Don't imagine what a changed line of code would do to the output - see it instantly! Experimenting and optimizing the visualization through code can be fun.

✓ Stable platform. Existing code will run in future versions

When you develop a visualization you want to be sure that it will be runnable in the future. The info-beamer API was carefully designed and didn't have any breaking changes so far. Code that was written years ago will still work with the latest version. Often you even get an increase of performance for free.

✓ Reliable runtime. The same visualization can run for months without problems

info-beamer has been developed very carefully to avoid problems like memory leaks or any other problem that might force you to restart info-beamer after a while. If your visualization is running smoothly now, you know that it will stay that way. There is no need for things like a nightly reboot.

Try info-beamer pi now

Why info-beamer pi is awesome

This is a Raspberry PI

Introducing info-beamer pi

info-beamer is a programmable visualization framework

How info-beamer code looks like

info-beamer can load different file formats

Let's animate things

Dynamic content

No wheels reinvented

Multiple Channels

Rapid development

Why choose info-beamer?

Cloud Digital Signage

Hardware

About

Signage Toolkit

Use Cases

Developers

API Documentation