Webcam

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Camera + Static mount + Network Transmission

History

Trojan_Room_coffee_pot_xcoffee.png

wikipedia: Trojan Room coffee pot

Webcam

Initially a "webcam" referred to a website (or URL thereof) where once could view a feed of (nearly) live pictures. The actual detail of the setup (the kind of camera and how it was connected to the web) was less secondary to the general assemblage in which an automated process continually sends pictures from a statically mounted camera making these available at some (public) web page or address.

Webcams were often displayed as static images (using HTML's image tag) combined with "meta refresh" tags to force a page to periodically reload. Java applets were also used to make more sophisticated (and fluid) viewers that could refresh their image without reloading their containing pages.

The contemporary meaning of a kind of camera that attaches (via USB) or more commonly is built in to a computer marks a shift, most notably to a device that is now typically used in private point-to-point conversations (via a program such as Skype).

The term 'webcam' (a portmanteau) may also be used in its original sense of a video camera connected to the Web continuously for an indefinite time, rather than for a particular session, generally supplying a view for anyone who visits its web page over the Internet. Some of them, for example, those used as online traffic cameras, are expensive, rugged professional video cameras.

Always On

irational.org/cctv Heath Bunting

Some live webcams

Work

Software

Example

Some code to use gstreamer to make a live webcam stream (using Icecast)...

gst-launch-0.10 \
oggmux name=mux ! shout2send ip=79.99.202.57 password=hackme mount=variable.ogg \
alsasrc device="plughw:CameraB404271" ! audio/x-raw-int,rate=8000,channels=1,depth=8 ! queue ! audioconvert ! \
vorbisenc ! queue ! mux. \
v4l2src  ! 'video/x-raw-yuv,width=320,height=240,framerate=30/1' ! videorate max-rate=4 !  theoraenc ! mux.

http://variable.constantvzw.org/define/index.php/PiEye

other links