piwall-setup

Setup Documentation and example config files for Raspberry Pi Video Wall

Setup

Setup documentation can be found here

The setup.sh script should cover everything required to setup each Raspberry Pi.

Config

The documentation for the config files can be found at the piwall website. Each Raspberry pi requires a .piwall and .pitile file in the home folder. These files dictate the layout of the screens, their dimensions and offsets.

.pitile

The .pitile is simply an identifier for that specific Raspberry Pi in the Pi Wall.

It looks like

[tile]
id=pi?

where ? is a number identifying that pi.

.piwall

The .piwall file is the same for each Raspberry Pi and it has the format

[Wall_Name]
width=Video-Width-Resolution
height=Video-Height-Resolution
x=X-coordinate-screen-offset
y=Y-coordinate-screen-offset

# corresponding tile definitions
# Repeat for N screens
[Tile_Config_Name_??]
wall=Wall_Name
width=width_in_pixels_of_tile
height=height_in_pixels_of_tile
x=X-offset-in-video
y=Y-offset-in-video

# config
[Config-Name]
pi?=screen_id_?? # Repeat for N screens

[Wall_Name]

This section defines the total size of the screens and the offset when displaying. If all the screens are the same size, and the video resolution matches, an offset should not be required.

[Tile_Config_Name_??]

Tile Config section should be repeated for each screen. The width and height essentially dictate how many pixels to use from the video.

Example:

If you have a video with resolution 1280 x 720 and a screen with native resolution 1280 x 720, setting:

width=1280 and height=720 will display the video fullscreen

width=640 and height=360 will under-scan the video and only the top left corner of the video will display

width=2560 and height=1440 will overscan the video and the full video will be in the top left corner of the display

The x and y value will shift the starting co-ordinate inside the video

Example:

If you have a video with resolution 1280 x 720 and a screen with native resolution 1280 x 720, setting:

x=640 and y=360 will display the bottom right corner of the video overscanned.

x=640 and y=360,width=640 and height=360 will display the bottom right corner of the video fullscreen.

x=-640 and y=-360,width=2560 and height=1440 will display the video in the top right corner over-scanned

I would recommend starting using only a single tile in order to get to grips with how the videos are laid out.

Multiple Display Sizes

Example: 2 displays of different sizes

Alignment: Centre
Orientation: 2 x 1

	Display 1	Display 2	Ratio
width	6400 mm	5150 mm	1.24
height	3450 mm	2900 mm	1.18
Aspect	1.85	1.77

Overscan:

# Calculate overscan
video-reolution=1280x720
width=1280*1.24
width=1587
height=720*1.24
height=892

Offset:

# calculate offset
x=(1280-1280*1.24)/2
x=-153
y=720/2
y=360

.piwall

# wall definition for 2x1 screens with bezel compensation
# video 1280 × 736
[2x1_wall]
width=1280
height=720
x=0
y=0

# corresponding tile definitions
[tile_1]
wall=2x1_wall
width=1280
height=720
x=0
y=-360

[tile_2]
wall=2x1_wall
width=1587
height=892
x=-153
y=360

# config
[2x1]
pi1=tile_1
pi2=tile_2

Master function call

avconv -re -i $FILENAME -vcodec copy -f avi -an udp://239.0.1.23:1234

infinite loop

while true; do avconv -re -i $FILENAME -vcodec copy -f avi -an udp://239.0.1.23:1234; sleep 2; done

Tile function call

pwomxplayer -y --config=2x1 udp://239.0.1.23:1234?buffer_size=1200000B

Rotate screen

in sudo nano /boot/config.txt add

display_rotate=0 # no rotation
# display_rotate=1 # 90º
# display_rotate=2 # 180º
# display_rotate=3 # 270º

Use Cases

Sync a video with max resolution 1920 x 1080 over multiple displays
Create a video wall from a source with max resolution 1920 x 1080

Edinburgh-College-of-Art/piwall-setup