A webcam is a digital camera connected to a computer. The device is designed for scanning, processing and transmitting images via the Internet in real time. Most often used for online broadcasts and video calls.
Historic Coffee Stream
The first webcam is the invention of the Cambridge geniuses Quentin Stafford-Fraser and Paul Jardetski. The device appeared in 1991 thanks to the love of university employees for coffee. At that time, there was only one coffee pot in the Trojan Room for the entire computer development department. Often, scientists had a long way to go for a cup of this wonderful drink for nothing. So that everyone can see if the coffee is ready without getting up from the workplace, a web-camera was created.
Initially, the image was broadcast only to the department’s work computers on the local network and was 128 × 128 pixels in size. The development received the client name XCoffee under the X Window System protocol . Online broadcasting lasted 10 years. In 2001, despite the protests of fans, the camera was turned off. The coffee pot became a famous rarity and was sold at eBay for £ 3,350.
Modern webcam device
The main part in the webcam is the image sensor, or CCD-matrix. It is a semiconductor chip consisting of millions of tiny photosensitive squares arranged in a grid. These squares are called pixels. Basic webcams use relatively small sensors, only a few hundred thousand pixels.
In addition to a 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 the webcam
A standard webcam is a separate device connected to a computer. It acts as follows:
- Through the front lens, the camera captures the light and projects it onto an integrated circuit consisting of microscopic light detectors.
- A 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.
- Further information is transmitted to a computer via a USB interface, and then to the Internet.
In the case of IP cameras, connecting to a computer is optional. The device has its own IP address, thanks to the built-in web server, and streaming is carried out 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 sensor and a lens. How to understand which one works well and which does not?
- Resolution - the number of pixels vertically and horizontally 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, that is, 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 speed 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-sized cameras, such as the Microsoft VX-1000 or VS-800, have a frame rate of 30 frames per second with a resolution of 640 × 480. If you sit motionless during video chat, then even with low fps the image will be quite clear. But for shooting in motion, the frequency indicator should be above 40 frames per second.
These are two key parameters that determine the level of the webcam. There are additional options that almost do not affect the quality of the device and image. They mainly affect the price, and not always justified.
What is a webcam for?
The task of the webcam is to show objects that are out of sight and reach. With its help, you can remotely monitor people, rooms in real time. For example, if you are going to another city or the sea, the webcam will show the weather better than any weather forecaster.
90% of users purchase a gadget for video calls, chats and video conferencing over the Internet. For this, a special software supporting VoIP must be installed on the computer: Skype, ooVoo or Viber. Instead of client programs, you can use the extensions for the Appear.in or Hangouts browser. But on video chats, the range of camera capabilities does not end there:
- Live 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 for monitoring facilities.
- Video from a webcam can be recorded, edited, uploaded to 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.
- Using web applications, create emails in video format.
- Conduct paid training webinars and earn money using the gadget.
Unconventional ways to use a webcam
Broadcasts from webcams to the sea, embankments, from an eagle's nest in the Himalayas no longer surprise anyone. But there are some unusual and fun ways to use the gadget:
- Interactive games: OvO Webcam Games or GloopIt Webcam Utility. Members control their characters through a webcam. For such entertainment, the monitor needs to be aimed at itself and with the movements of all parts of the body to complete quests. Gaming software is downloaded from the Internet and installed on a computer.
- Using 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 still in alpha testing.
- Create animated GIFs and avatars using WebCam Avatar or PsykoGif.
- Use the face recognition program to enter the account without entering a password.
From a webcam with a built-in microphone, PC and Skype, each attentive parent can mount a video nanny. To do this, in the messenger you need to create a new account in the name of the child, add yourself and relatives to the contact list. Set Skype to automatically answer the 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, one can observe a child at any time.