Difference between revisions of "Projector client"

Revision as of 20:12, 21 May 2014

The projector client allows users to share their content without requiring them to connect physically to the projector or sound system. This facilitates sharing of media such as music, videos, and photos; as well as sharing your desktop during workshops and presentations. The idea is that everyone can easily share just about anything, with ease, from just about any device.

_{Todo list for improvements and fixes}

Usage

• SSH Acces:

ssh -p 47382 pi@projector.fixme.ch

Linux

Mac

Windows

Android

Goal

Data goals

• Presenters to broadcast their presentations or demonstrations remotely during workshops
• YouTube and other streaming video to be streamed directly to the projector
• Play music directly from personal library or music streaming services (e.g. Pandora)
• Share project photos or videos directly from personal devices
• Your idea here

Control goals

• Turn on and off projector using IR signals (to allow for cooling)
• Have a script that automatically launches the correct data source
  • Maybe use a dedicated port for streaming, then run nmap every x seconds scanning for port, and then stream from the correlated IP?
    • e.g 5905 for VNC
    • e.g 1205 for HTTP x264 streams
• Link with trigger interface?

Component

Implemented

VNC

xtightvncviewer in reverse VNC listening mode on Pi DISPLAY=:0 vncviewer -listen 0 -fullscreen -x11cursor #on pi (scripted already)

x11vnc or your favourite server on your laptop, Veency on iOS, DroidVNC or others on Android

Works well, however the frame rate is too low for videos, and the resolution can be a bit finicky. If your laptop isn't set to 720x480 or 640x480, the screen will move around with your mouse.

AirPlay & Chromecast

rPlay is used for AirPlay and Chromecast. Sending music over airplay works fine most of the time, mirroring works intermittently - seems to depend on the number of devices on the network. Chromecast works sometimes, it seems that Youtube works best right now. Streaming side-loaded google music or any DHCP content does not work.

Chromecast using rPlay does not function very well, do not hesitate to suggest alternative servers.

DLNA/UPnP

Gmrender is used for DLNA/UPnP. This works excellently, apps on Android phones can stream music without difficulty to the sound system.

If you're using apps like BubbleUPNP, make sure you deactivate your personal media server so that others can't see all the music/videos/photos on your device.

PulseAudio

Raspberry Pi pulse audio guide. This was a pain to set up, however now you can select 'bcm2835 ALSA Analog Stereo on pulse@projector' on your laptop that has pulseaudio. Doesn't work very well over WiFi. There also seem to be issues with discovery, debian doesn't seem to pick it up, but ubuntu does - to be troubleshooted. The buffer also needs to be setup...

Last FM Scrobbling

Scrobbles (aka shares what's currently playing) music from MPD to our Last.fm account. You can have fancy visualisations such as this, and charts/stats such as this. The scrobbling is done by mpdas (thanks dgellow!).

Not Implemented

• HTTP x264/h264 Desktop Mirroring allows for less lag/higher framerate compared with VNC, seeing as the RPi has a hardware decoder, and compression helps overcome the RPi's bandwidth limitations (100mbit). Installing VLC with hardware acceleration on Pi. Using VLC for screen sharing. Status: VLC installed, but was a huge massive pain to set up with proper hardware rendering. Should work, but it's untested and un-configured yet.
• Limelight is an open-source Java client which allows you to stream games from your home PC (as long as you have an Nvidia GTX 600 or 700 Series graphics card and enough bandwidth on your home network) to the Raspberry Pi that’s attached to your television. Status: not implemented, may be installed if there is demand in the future.
• MPD is a music player demon that runs on a server, and is controllable from any device connected to the network. RaspyFi is a distro specifically made for this. Status: not implemented, this is currently handled by foo.
• PiCast opens links and plays streaming videos in fullscreen, Chromecast style. You can open links by sending it via an URL. Status: implemented but removed due to very poor performance and difficulty in setting up correctly. Not very useful either.
• Synergy allows for remote keyboard/mouse control. Status: installed, and then removed. Why? Because.
• MiraCast offers native screen sharing for many Android devices. Status: OSS implementation wasn't available when the project started, however there is one now (Piracast) which requires a TP-Link dongle and doesn't work with DRMd material. May be implemented in the future.
• RDP is a Windows remote desktop utility, although proprietary, there are open source clients such as FreeRDP. Status: in the future if there is demand.
• Spotify will play most music you want, and can be used on the Pi using mopidy. Nevertheless, it requires someone with a premium subscription. Status: if someone has a premium subscription they're willing to share, let us know.

Control

Use RPi to turn on/off projector via IR LED, also (maybe) change the input of the stereo system. [1]

https://github.com/afaqurk/linux-dash?utm_source=explore-newsletter&utm_medium=email&utm_term=weekly&utm_campaign=explore-email

Schedule

• December 2013 - Zephyz bought pi with 10 CHF contributions from gcmalloc, sasha and noskill. The SD Card was provided by fixme/rorist. Raspbian was set up and updated, ssh access was set up, and experimentation began.
• January 2014 - The Raspberry Pi was mounted in a custom 3D printed holder next to the projector, all the wires were hooked up. PiCast, VNC, Synergy and AirPlay were installed.
• February 2014 - Proper Airplay (with screen mirroring) and Chromecast were installed. An IR receiver and LED was hooked up in order to be able to control the projector remotely. A splitter was attached to the audio line to allow for playback from both MPD and the projector without switching.
• March 2014 - Synergy and Picast removed due to poor performance. A DLNA/UPnP receiver was set up on the Pi to allow streaming media from devices such as Android phones & tablets. A Pulseaudio sink was also installed. We experimented with an external DSP to amplify sound, however this didn't work. Reverse VNC now runs on startup so there is no need to run script each time.

Participants

• Sasha (Leader)
• Francois
• Other ppl