Having Fun on ViewSurf

This article explains how Linux is used in the ViewSurf “Beach Report”, a fun WebCAM-based service.
The Future of ViewSurf

Beach Report and Snow Report are free services for the end user, but Nicolas created ViewSurf in the hope of making some money with it. He's currently trying to sell the service to French Tourism Offices, but it's quite hard; basically, France is lagging in communications and Internet services. Additionally, many French people consider computers and the Internet as American Trojan horses such as McDonald's or Disneyland Paris.

Most French on-line services are available for a low performance Videotex-compatible terminal called Minitel, which was distributed free of charge by France Telecom at the beginning of the 1980s. This technology is obsolete, but France Telecom is currently the only French operator for communications. The Minitel allows them to charge up to several dollars per minute for some on-line services. This could be the reason why most French people don't have a PC at home, and as a result, Internet-based services are not seriously considered.

Nicolas has gotten a contract with the government organization which deals with traffic regulation in Paris. Some French highways have been on the Net since September 1997. If you compare it with other WebCAM systems, ViewSurf gives very good quality for a small data size.

This software would be more easily configurable without editing crontab or shell scripts each time you wished to change the call time or add a new site. To that end, I wrote a set of CGI (Common Gateway Interface) scripts which present a simple and portable interface for the Linux server configuration. The advantage of using CGI instead of standard Linux programs is the capability to configure the server from any forms-capable browser running on any operating system.

Another crucial option is to have the ability for several users to look at a “live” video (not recorded files) at the same time. For this, the Linux PC could be used as a server to distribute the live image from ViewCOM to several users connected from the Net. To reach this goal, I wrote a multi-threaded Linux daemon, based on the POSIX 1003.1c LinuxThreads library by Xavier Leroy (http://pauillac.inria.fr/~xleroy/linuxthreads). Actually, this daemon handles only the “video/x-vcr” MIME type and uses two specific TCP ports. The live video can be inserted in an HTML page with a line such as:

<EMBED SRC="http://your_linux_server:daemon_port"

The second port is reserved for ViewCOM administration, such as setting brightness or contrast. Additionally, the daemon can control a weather station in order to get real-time information about external temperature, wind speed and other weather information. A VISCA (a standard for video camera remote control) functionality is about to be added to control zoom, pan-and-tilt and other camera parameters directly from the Internet browser. Figure 4 is a snapshot of the Bordeaux/Bayonne motorway on the private COM1 web server.

Figure 4. Snapshot of Bordeaux/Bayonne Motorway

The ViewCOM is often connected to the PC via a serial line, but one of the most important advantages of the system could be the ability to control a remote ViewCOM. So, it's not necessary to install a PC on the site you want to look at, you just have to set up a ViewCOM connected to a simple phone line or a leased line. In the phone line case, it's possible for the daemon to call the ViewCOM at starting time or only when an HTTP request occurs. In this last case, the daemon hangs up the line when the last client is disconnected.

References and Contact

Pierre Ficheux is in charge of system development at Lectra-Systèmes, Cestas, France. When not doing something with Linux, he loves picking tunes on his guitar on the nice beach at Arcachon. He can be reached by e-mail at pierre@rd.lectra.fr.



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Similar setups

toys's picture

Interesting article. I think Linux was a very good choice in automating this process. I have spotted many home – CCTV systems, such as ViewSurf here, that are available through a Linux set up and got quite excited about some of the prospects. Having got my brother to use one of them, it looks like a definate cheaper option for the same kind of quality you would get through a Windows or other kind of system.

advanced config

linux fun's picture

yes, the basic configuration of the ViewSurf service is quite simple, but there isn't much documentation for doing advanced stuff.

where to find a recent vcr plugin for linux ?

Chiff's picture

I would like to know, where I could find a recent video/x-vcr plugin for Linux, because the versions I have seems not to work.
I woul be interrested in a video converter from vcr to mpeg