client

Flaschen Taschen Clients

Useful utilities to send content to the FlaschenTaschen installation.

This directory provides:

• send-text binary, that prints a static or scrolling text.
• send-image binary, that reads an arbitrary image (including animated *.gifs), scales it and sends to FlaschenTaschen.
• send-video binary, that reads an arbitrary video, scales it and sends to FlaschenTaschen.

Network destination

The clients connect to the display over the network. The default hostname is pointing to the installation within Noisebridge (currently ft.noise).

You can change that with commandline flags (e.g. send-text, send-image, and send-video all have a -h <host> option) or via the environment variable FT_DISPLAY.

So if you are working with a particular instance of FlaschenTaschen (e.g. a local terminal), just set the environment variable for ease of playing.

export FT_DISPLAY=localhost

UDP Size

The images are sent via UDP, and if the size does not fit in a single packet, it will be split up into multiple stripes, so even large screens are supported.

The default assumed size of a maxium UDP packet is 65507 bytes (65535 - IP and UDP header), but note that on some operating systems (notably OSX), the default allowed size is smaller. If you try to send a large image or video and you get error messages, this might be the reason.

To fix: Either tell the client tool such as send-video to use a smaller UDP size with the environment variable FT_UDP_SIZE. E.g.

FT_UDP_SIZE=8000 ./send-video -g320x200 ...

This will split the image into more stripes, so requies more network packets, but it will work.

Or, if your operating sytem allows, set a larger limit. On OSX this would be:

sudo sysctl -w net.inet.udp.maxdgram=65535

Send-Text

Compile

make

Use

usage: ./send-text [options] <TEXT>
Options:
        -g <width>x<height>[+<off_x>+<off_y>[+<layer>]] : Output geometry. Default 45x<font-height>+0+0+1
        -l <layer>      : Layer 0..15. Default 1 (note if also given in -g, then last counts)
        -h <host>       : Flaschen-Taschen display hostname.
        -f <fontfile>   : Path to *.bdf font file
        -s<ms>          : Scroll milliseconds per pixel (default 60). 0 for no-scroll.
        -O              : Only run once, don't scroll forever.
        -S<px>          : Letter spacing in pixels (default: 0)
        -c<RRGGBB>      : Text color as hex (default: FFFFFF)
        -b<RRGGBB>      : Background color as hex (default: 000000)
        -o<RRGGBB>      : Outline color as hex (default: no outline)
        -v              : Scroll text vertically

Sample

./send-text -f fonts/6x10.bdf "We ♥ Flaschen Taschen"

# Or coordinated horizontal and vertical messages
./send-text -h localhost "♥Flaschen" -f fonts/5x5.bdf -s 60 -g 45x35+0+15+3 & ./send-text -h localhost "Taschen " -f fonts/5x5.bdf  -v  -s 60 -g 45x35+20+0+2 && fg

# Or, how about showing the time
while : ; do sleep 1 ; ./send-text -f fonts/9x18.bdf -s0 `date +%H:%M` ; done

Text has a default layer of 1, so it is hovering above the background image. If you don't want that, you can explicitly set it as last value in the geometry specification.

If you add a -o color, then the font gets an outline of that given color, which you can use to create a contrast for the font.

Send-Image

Compile

# Need some devel libs
sudo apt-get install libgraphicsmagick++-dev libwebp-dev
make send-image

Use

usage: ./send-image [options] <image>
Options:
        -g <width>x<height>[+<off_x>+<off_y>[+<layer>]] : Output geometry. Default 20x20+0+0+0
        -l <layer>      : Layer 0..15. Default 0 (note if also given in -g, then last counts)
        -h <host>       : Flaschen-Taschen display hostname.
        -s[<ms>]        : Scroll horizontally (optionally: delay ms; default 60).
        -C              : Just clear given area and exit.

Essentially just send the FlaschenTaschen display an image over the network:

./send-image -g10x20+15+7 some-image.png

Image will be scaled to the given size (here 10x20) and shown on the FlaschenTaschen display at the given offset (here 15 pixels x-offset, 7 pixels y-offset).

The program exits as soon as the image is sent unless it is an animated gif in which case send-image keeps streaming until interrupted with Ctrl-C.

If you want to scroll a long image accross the display, use the -s option. In this case, only the height is scaled to the display height and the image is scrolled infinitely over width.

Let's try this with an example image:

./send-image -s ../img/flaschen-taschen-black.ppm

Send-Video

This utility here is a simple video output without sound.

The upstream VLC now has FlaschenTaschen support natively, so this might be the better option these days (currently, you have to compile it from source to get this bleeding edge).

Compile

# Need some devel libs
sudo apt-get install libavcodec-dev libavformat-dev libswscale-dev
make send-video

Use

usage: ./send-video [options] <video>
Options:
        -g <width>x<height>[+<off_x>+<off_y>[+<layer>]] : Output geometry. Default 20x20+0+0
        -h <host>          : Flaschen-Taschen display hostname.
        -l <layer>         : Layer 0..15. Default 0 (note if also given in -g, then last counts)
        -v                 : verbose.