Hardware Architecture

For 2016, 2 types of boxes are in use: 1 type connected to a camera, and 1 connected to a presentation laptop.

The main components of the boxes are the following:

• Blackmagicdesign H.264 Pro Recorder (BMD)

  This is a professional-grade H264 encoder that can encode a signal from HDMI, SDI or Component video to an encoded MPEG2 Transport Stream over USB.

  Altough intended for Video-on-demand encoding only, there is exists a libusb-based driver to encode the stream in real-time with only a slight delay.

• Banana Pi (Banana Pi)

  The banana pi is a small development based on the allwinner A20 chipset.

• [Banana Pi 3.5" LCD Module](http://www.lemaker.org/product-bananapi-specification.html "Banana Pi 3.5" LCD Module") (LCD)

  An LCD Module that works flawlessly with the Banana Pi. Used for status display on the box itself.

• Sandisk SDSSDP-064G-G25 (SSD)

  A regular SSD with SATA connection connected to the Banana Pi. Used for local storage of recordings.

• Gigabit Network Switch (Network)

  A regular Gigabit-capable network switch, with 3 RJ-45 connectors exposed to the outside of the box.

In addition to the basics, the presenter boxes have the following extra components:

• Lenkeng LKV391 MINI Switch (Scaler)

  A device that can take VGA, HDMI or Composite video in, combines it with audio where needed and scales the output into a desired resolution on HDMI.

• VGA Splitter (Splitter)

  A simple VGA splitter that allows for simulatneous input of the VGA signal to both the scaler and the output port.

Schematics

The Camera box is wired as follows:

+------+    +-----+
| HDMI |    | SDI |
+--+---+    +---+-+
   |            |
   |  +-----+   |
   +--+ BMD +---+
      +--+--+
         |
   +-----+-----+    +-----+
   | Banana Pi +----+ LCD |
   +-+-------+-+    +-----+
     |       |
+----++    +-+-------+
| SSD |    | Network |
+-----+    +---------+

The Presenter box is wired as follows:

+---------+   +----------+   +--------+
| JACK In |-+-| JACK Out |   | VGA In |
+--+------+ | +----------+   +--+-----+
            |                   |
            | +--------+   +----+-----+  +---------+
            +-+ Scaler +---+ Splitter +--+ VGA Out |
              +---+----+   +----------+  +---------+
                  |
               +--+--+
               | BMD |
               +--+--+
                  |
            +-----+-----+   +-----+
            | Banana Pi +---+ LCD |
            +-+-------+-+   +-----+
              |       |
         +----++    +-+-------+
         | SSD |    | Network |
         +-----+    +---------+