A webcam is a digital camera connected to a computer. The device is designed for scanning, processing and transmission of real-time images via the Internet. Most often used for online broadcasts and video calls.
Historic Coffee Stream
The first webcam was invented by Cambridge geniuses Quentin Stafford-Fraser and Paul Jardetsky. The device appeared in 1991 thanks to the love of coffee by university staff. At that time, there was only one coffee pot in the entire computer development department in the Trojan Room. Often scientists had to go a long way for a mug of this wonderful drink in vain. So that everyone can see if the coffee is ready without getting up from the workplace, a webcam was created.
Initially, the image was broadcast only to the working computers of the department via the local network and was 128×128 pixels in size. The development received the client name XCoffee under the X Window System protocol. Online broadcast lasted 10 years. In 2001, despiteto protests from fans, the camera was turned off. The coffee pot became a famous rarity and was sold on eBay for £3,350.
Modern webcam device
The main part of a webcam is the image sensor, or CCD-matrix. It is a semiconductor chip consisting of millions of tiny light-sensitive squares arranged in a grid. These squares are called pixels. Basic webcams use relatively small sensors, only a few hundred thousand pixels.
Besides the CCD or ROM-matrix, the camera contains a lens, an analog-to-digital converter, also called a video capture card, a microprocessor and a compressor. Some IP camera models include a built-in web server and RAM.
The principle of operation of the webcam
A standard webcam is a separate device connected to a computer. Works as follows:
- Through the front lens, the camera captures light and projects it onto an integrated circuit made up of microscopic light detectors.
- The video capture card converts an analog image into a digital one, that is, into a bytecode of zeros and ones.
- Compression units compress the digital signal into MJPEG or MPEG formats.
- Then the information is transferred to the computer via the USB interface, and then to the Internet.
In cases with IP cameras, connection to a computer is not necessary. The device has its own IP address, thanks to the built-in web server, andstreaming directly to the network.
Webcam settings
If you disassemble two webcams in parts, you get an identical set of parts: a board with a photosensitive matrix and a lens. So how do you know which works well and which doesn't?
- Resolution - the number of pixels vertically and horizontally of the matrix. The more of them, the device is considered better and more expensive. Modern HD webcams in real time transmit images with a resolution between 1280×720 and 1600×1200, i.e. 3-2.0Mpx. For budget models, this parameter is 320 × 240 or 640 × 480. The picture is grainy, sometimes blurry. But not every internet connection will pull a 2.0Mpx camera. If the data transfer rate is low, up to 10-20 Mb, the image will hang.
- FPS - the number of frames per second that the camera is capable of processing. For inexpensive models, the frequency is about 24 frames per second, for PRO cameras this value reaches 50-60. Medium cameras such as the Microsoft VX-1000 or VS-800 are capable of 30 frames per second at 640×480 resolution. If you sit still during a video chat, then even with low fps, the image will be quite clear. But for shooting in motion, the frame rate must be above 40 frames per second.
These are two key parameters that determine the level of the webcam. There are additional options that have almost no effect on the quality of the device and the image. Basically, they affect the price, and not always justified.
Why do you need a webcamera?
The task of the webcam is to show objects that are out of sight and reach. With its help, you can remotely monitor people, premises in real time. For example, if you are going to another city or the sea, the webcam will show the weather better than any forecaster.
90% of users purchase a gadget for video calls, chats and video conferences over the Internet. To do this, a special software that supports VoIP must be installed on the computer: Skype, ooVoo or Viber. Instead of client programs, you can use the Appear.in or Hangouts browser extensions. But on video chats, the range of camera capabilities does not end:
- Online broadcasts of what is happening in the most popular corners of the earth. Webcams in Sochi, New York and near Niagara Falls allow you to travel without getting up from your computer chair.
- Security companies and security services widely use this technique to monitor objects.
- Video from a webcam can be recorded, edited, posted on the Internet, on forums, in a YouTube playlist or on a blog. For these purposes, there are many programs, one of which is Windows Movie Maker or Camtasia Studio.
- Create emails in video format using web applications.
- Conduct paid training webinars and earn money with your gadget.
Unconventional ways to use your webcam
Broadcasts from webcams on the sea, embankments, from the eagle's nest in the Himalayas no longer surprise anyone. But there are some unusual and fun ways to usegadget:
- Interactive games: OvO Webcam Games or GloopIt Webcam Utility. Participants control their characters via webcam. For such entertainment, you need to point the monitor at yourself and complete quests with the movements of all parts of the body. The game software is downloaded from the Internet and installed on the computer.
- Use gesture recognition technology to control desktop software, YouTube, Pandora, Grooveshark and Netflix players in the Chrome browser. The mouse and keyboard are not used, only the movement of the brushes. The development is called Flutter and is currently in alpha testing.
- Create animated GIFs and avatars using WebCam Avatar or PsykoGif.
- Use a facial recognition program to log into your account without entering a password.
From a webcam with a built-in microphone, PC and Skype, every attentive parent can mount a baby monitor. To do this, you need to create a new account in the messenger in the name of the child, add yourself and relatives to the contact list. Set Skype to automatically answer a video call and turn on the camera. A computer with a gadget must be installed so that the entire nursery is visible, including the child itself. With this know-how, you can watch the baby at any time.
