This page attempts to set out options for live video streaming from a mobile device, either over wifi, 3G or perhaps even bluetooth.
The reason you might want to do this are either to broadcast live video from a remote location for instant viewing by a third party audience (the public probably) or to ensure that the video footage has been 'beamed' safely offsite so that should your camera person be detained or their equipment seized, you'll still have the footage somewhere safe to review and publish as appropriate.
You have various options here but this 'guide' will concentrate on the Nokia N series mobile phones running Symbian S60 version 3 although much of what we cover will probably be applicable to other systems. Specifically, this 'guide' uses the Nokia N95-1 which can now be purchased second hand for under £100 unlocked. It features 3G, bluetooth and wifi and boasts a very capable camera which can render 640x480 at 30 frames per second.
Other options might include webcams - either built into or plugged into a laptop or a webcam plugged into somekind of embedded device such as a router or NAS running a suitable linux distro. Better still (in terms of less kit and investment) would be an IP camera plugged into a wifi router or better yet, a Wifi IP camera.
Of course digital is not the only option here - it is also possible to transmit analogue video and video short distances using 2.4 or 5 ghz video senders. To obtain greater range directions antennas can be used, or even microwave amplifiers. The disadvantage with analogue is that you'll probably want to digitize it anyway and doing that at source is almost certainly more efficient. The advantage is price as a CCTV camera and sender is probably much cheaper than most other options.
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