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First developed in 1991, a webcam was pointed at the Trojan Room coffee pot in the
Cambridge University Computer Science Department (initially operating over a local
network instead of the web). The camera was finally switched off on August 22, 2001.
The final image captured by the camera can still be viewed at its homepage in 2004,
the oldest webcam still operating was FOGCAM at San Francisco State University,
which had been running continuously since 1994
The first commercial webcam, the black-and-white QUICKCAM, entered the
marketplace in 1994, created by the U.S. computer company Connectix (which sold its
product line to Logitech in 1998

? Webcam is a device used to
capture images, audio and
videos. Webcam are either
inbuilt or can be externally
attached with the laptop or
the computer. The most
common application of a
webcam is video chat, video
recording, image capturing.
A webcam generally consist
of a lens, an image and
sound sensors, electronic
circuitry to process the data
and send it to PC. A variety
of webcams with different
features are available in the
markets. Depending on the
features and quality, the
technologies used and the
prices vary. However the
basic function remains the
same.

? You'll want a Webcam system
with a high frame rate.
? Frame rate indicates the number
of pictures the software can grab
and transfer in one second. For
streaming video, you need a
minimum rate of at least 15
frames per second (fps), and 30
fps is ideal.
? To achieve high frame rates, you
need a high-speed Internet
connection.
? Once it captures a frame, the
software broadcasts the image
over your Internet connection.

? Webcam software turns an image into a JPEG file
and uploads it to a Web server using File Transfer
Protocol (FTP). You can easily place a JPEG image
on any Web page.

In principal, a digital camera is similar to a traditional film-based camera. There's a
viewfinder to aim it, a lens to focus the image onto a light-sensitive device, some
means by which several images can be stored and removed for later use, and the
whole lot is fitted into a box. In a conventional camera, light-sensitive film captures
images and is used to store them after chemical development. Digital photography
uses a combination of advanced image sensor technology and memory storage, which
allows images to be captured in a digital format that is available instantly - with no
need for a "development" process.

Although the principle may be the same as a
film camera, the inner workings of a digital
camera are quite different, the imaging being
performed either by a charge coupled device
(CCD) or CMOS (complementary metal-oxide
semiconductor) sensors. Each sensor
element converts light into a voltage
proportional to the brightness which is
passed into an analogue-to-digital converter
(ADC) which translates the
fluctuations of the CCD
into discrete binary cod.

Webcams
typically
include a lens
(shown at top),
an image
sensor (shown
at bottom), and
supporting
circuitry

The digital output of the ADC is sent to a digital signal processor (DSP) which adjusts
contrast and detail, and compresses the image before sending it to the storage
medium. The brighter the light, the higher the voltage and the brighter the resulting
computer pixel. The more elements, the higher the resolution, and the greater the
detail that can be captured.
This entire process is very environment-friendly. The CCD or CMOS sensors are fixed in
place and it can go on taking photos for the lifetime of the camera. There's no need to
wind film between two spools either, which helps minimize the number of moving part

? Motion sensing - The Webcam takes a new picture when it detects motion.
? Image archiving - You can create an archive that saves all of your Webcam
images or only certain images at pre-set intervals.
? Video messaging - Some instant messenger programs support Webcam video.
? Advanced connections - Use wired or wireless methods to connect your
home-theater A/V equipment to your Webcam.
? Automation - Robotic cameras let you set a series of pan/tilt positions and
program frame-capture settings based on the position of the camera.
? Streaming media - For professional applications, a Webcam setup can use
MPEG4 compression to achieve true streaming audio and video (this is the
compression system used in most of the popular PC-based media players).
? Custom coding - Import your own computer code to tell the Webcam what to
do.
? One example of custom coding is a set of commands that makes a Webcam
image automatically refresh.

? You will be out of town for a week and you want to
keep an eye on your house.
? You'd like to be able to check on the baby sitter and
make sure everything is OK while you are at work.
? You'd like to know what your dog does in the back
yard all day.
? You want to let the grandparents watch the new
baby during nap time.
? Video Networking

? You can get software that will let you make video phone
calls with a friend who also has a Webcam.
? You can hold a video-conferencing session with business
associates on the other side of the world.
? You can conduct a video interview and broadcast it live on
your blog.
? Some Webcam software will even deliver images directly
to your Web-enabled PDA or smart phone.
? Other products let you connect your camcorder to your
Webcam setup so you can let everybody watch your
vacation footage via the Internet. The possibilities are
endless.

You can place a standard camera anywhere in the
house and run a video cable with RCA jacks on it from
the camera to the computer. There are all sorts of
places on the Web that sell small pinhole video
cameras, either on their own or embedded in things
like clocks and smoke detectors. You can find small
security cameras for less than $100.
You can avoid the cable by using a radio link (X10:
XRay Vision is one example of this type of product), an
Ethernet connection or a WiFi setup.

SOME
SOFTWARE AND APPS
FOR VIDEO CHATTING
AND
CONFERENCING

Just for starters you can instant
message with anyone on your contact
list or even use group chat to chat with
up to a hundred people.
You could hold a conference call with
up to nine other people to organize a
get-together and then use
SkypeFind? to search for the perfect
venue to hold it.

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