Hail the all seeing Great PumpkinPi!

The eye of the great pumpkin is upon you... so build this simple yet creepy animated pumpkin decoration to send fear into the neighbourhood and claim the throne as King of Halloween!

Supplies

Pumpkin large enough to contain a Raspberry Pi & a 3.5" display
Raspberry Pi SBC (and power/SD etc...)
Adafruit 3.5" display (or another appropriate display)

Step 1: Step 1: Pick Your Pumpkin Victim

The first step is deciding on what your PumpkinPi will look like.
I decided on a creepier cyclops look, but you could just as easily create a fun cartoonish character.

Get yourself a pumpkin that is large enough to accommodate a Rspberry Pi on the inside, as well as a display that is large (or small) enough for the look you are going for.

I wanted people to quake in fear before the might of the all seeing PumpkinPi eye, so I went with a medium sized round pumpkin and used the Adafruit 3.5" 320x480 TFT for the eye display.

Step 2: Step 2: Dig Out the Eye(s)

Carve out the eye(s) but check often to make sure that the diameter of the eye holes don't go past the edges of the display you're going to be using. You want to cover the whole eye hole with the screen on the inside of the pumpkin.

Find or create a video of the eyeball effect you want displayed. A nice closeup of the eye works great. Blink, look around, eyes are expressive and wonderfully creepy when inside a terror pumpkin!

I used the eye closeup video provided by Dreamearth (link below)

I found MP4 format worked best for the video playback on the Pi (see next step)...

Step 3: Step 3: Download Terror!

Once you have the pumpkin cleaned out and the eye hole cut, try to flatten the back of the eye hole (on the inside of the pumpkin) so your display board sites as flush to the pumpkin shell as possible to minimize light seepage.

I used baking toothpicks to hold the Pi/screen in place (since it only needs to last a night or two).

I won't cover how to install Debian & setup the base Pi, that's covered in detail many other places on the interwebs. But, once you have the Pi booting, configure it so your screen displays the command line.

If you're using the Adafruit (and other) displays, you can use mplayer with some command line trickery to play a video file in a loop without needing to install a whole resource hogging x windows desktop.

Install mplayer by entering:
sudo apt-get install mplayer

Then, with the video file loaded onto your Pi's SD card, simply run the video in an endless loop like this:
sudo SDL_VIDEODRIVER=fbcon SDL_FBDEV=/dev/fb1 mplayer -vo sdl -loop 0 -framedrop eye.mp4

I added framedrop so the video would not have any problems playing back on the limited Pi hardware. It just drops frames if it's getting laggy.

Step 4: Step 4: Profit! Err... Neighbourhood Terror!

Once your video is playing back properly in an endless loop and you're happy with the placement of your display screen in the pumpkin eye hole, close up your pumpkin and set it outside to strike fear into all who fall within it's unholy gaze!

If AC power isn't available where you want to place the Pumpkin, a good USB power brick (2500mAH) will keep this running for hours.

If your pumpkin is extra juicy/wet inside, you might want to place the Pi into a plastic project box, or at least electrical tape some cardboard to the backside of the board to keep it from coming into contact with the wet pumpkin shell.

Enjoy! :)