It is well-known that photo, video and web content on a mobile phone is difficult to share with a group in settings where there is no other digital technology to upload it to. Yet, these settings may have existing analogue televisions that could be used as public displays. By filming the screen itself from an overhead camera and taking a sound feed from the headphone socket of the phone, Com-Cam is a low cost device for relaying the screen and sound of a mobile phone to an analogue television. Cables from Com-Cam plug into the scart or audio-visual sockets of a TV switched to its AV input channel setting. A number of different versions for the device have been tried. The best one includes an adjustable “lamp-like” structure with a whiteboard or chalkboard base. The overhead camera is in the head of the lamp-like device which can be manually focussed, and moved up or down over the screen of any mobile phone which sits underneath. The mobile phone controls are left accessible while relaying the screen image at an appropriate scale to fill the TV screen.
The overhead camera also supports the use of Com-Cam as a whiteboard and overhead projector for making group
presentations on a TV. Writing or sketching on the whiteboard or chalkboard base appears on the TV screen. Usefully this
can also be done on paper for quick removal and replacement. Additionally, printed documents and other objects and materials can also be placed on the base for presentation on the TV screen, as with an overhead projector. Com-Cam has a built-in microphone which can be switched on in these situations for amplifying the speakers’ comments through the TV speakers. The electronic components of the device are readily available off the shelf in most countries and cost about £10. Our design shows how these components can be mounted on a simple lampstand made out of local materials such as boxes and rulers.
self-recorded video clips and narratives recorded on a Com-Phone can be shown to a group in a community TV session.
personal photographs on a phone can be shown to a group in a photo slideshow.
video content from websites such as YouTube, BBC iPlayer and film sites playing on a phone can be watched in a family or community group.
Public web browsing:
web pages displayed on a phone can be shown to a group.
writing or sketches can be made on the whiteboard base of Com-Cam and shown on the TV screen.
presentations can be given on a TV using paper documents. For example, picture books can be shown and read aloud to a class by a teacher, or printed health information can be explained to a community group.
small objects, textiles, insects and plants can be viewed in more detail on the TV screen
partially sighted people can use Com-Cam as a cheap magnifier for reading material.
smartphones supporting wireless keyboards can use the TV as a monitor to create a low cost workstation.
The Com-Cam project was funded by the EPSRC University of Surrey Knowledge Transfer Account No. EP/H500189/1 and managed by David Frohlich. It has involved design and early prototyping work from members and affiliates of Digital World Research Centre, including David Frohlich, Janko Calic, Risto Sarvas, Kristina Langhein, Ali Al-Azzawi, Connie Golsteijn, Chris Lim and Peter Lancaster. Trial units were designed and built by Justin Marshall and Adam Stringer from the Autonomatics Group at University College Falmouth. Indian trials were run by Kartik Bajpai and Ramnath Bhat from Maraa Media Collective, Bangalore. South African trials were run by Thomas Reitmaier and Gary Marsdaen from the University of Cape Town. Brand design was by Kristina Langhein.
Com-Cam is open source hardware whose design is now available to copy or adapt as part of the Com-Me toolkit: digitaleconomytoolkit.org
Use requires acknowledgement of Digital World Research Centre and Autonomatics as authors of the original design.