This is a characteristic of a webcam computer. Webcam - technical characteristics, how to choose, victoria rules. Connecting and installing a webcam

A digital webcam is a built-in add-on, which consists of a video camera (CCD matrix), a compression processor and a built-in web server. As a rule, a webcam is used as an attachment for video recording, video conferencing, or video monitoring and transmission of video images over the LAN/WAN/Internet. For the operation of the webcam in the city, you do not need special attachments and a personal computer. Freely in the field, access to the video image taken by the webcam can be applied to all coristuvachs of the line, or only to authorized coristuvachas.

Attach that principle of a robotic webcam

Today's webcam is a digital device that can capture video, convert analog video signal to digital, compress digital video signal and transmit video computer system. The following components are included in the stock of the webcam:

PZZ-matrix,

objective,

optical filter,

video storage fee,

video image compression (stiffening) block,

central processor and wake-up web server,

flash memory,

mesh interface,

aftermath,

anxious enter/exit.

Like a photo receiver, most webcams get stuck PZZ-matrix ( PZZ, CCD - an attachment from a charge link) - a straight-cut light-sensitive nap_providnikova plate with a setting of sides 3: 4, as if turning the light falling on it into electrical signal. The PZZ-matrix is ​​composed of a large number of light-sensitive centers. In order to increase the light sensitivity of the PZZ-matrix, it is often necessary to form a structure, as if creating a microlens in front of the skin center. For the technical parameters of the webcam, select the format of the PZZ-matrix (the length of the diagonal of the matrix in inches), the number of effective pixels, the type of scaling (row or through streak) and sensitivity.

Lens - a whole lens system, as it is recognized for projecting an image of a warning object on a light-sensitive element of a webcam. The lens is an invisible part of the webcam, so if the choice is correct, it is installed to store the quality of the video image that is taken by the webcam. Dosit often webcam is equipped with a lens. Objectives are characterized by a number of the most important parameters, such as focal length, aperture (F), sharpness depth, mounting type (C, CS), format.

Optical infrared filters , as installed at the webcam, are optically accurate plane-parallel plates that are mounted on the beast of the PZZ-matrix. The stench works like optical low-frequency filters with a frequency of about 700 nm near the red color. The stench is watching the infrared of the storehouse of light fluff, making sure that the webcams are correctly transferred to the colors. Prote, such filters are not installed on rich black-and-white webcams, which is why monochrome webcams can be more sensitive.

Video storage fee webcams (digitizing block) zdіysnyuє conversion of analog electrical signal, formed by PZZ-matrix, digital format. The signal conversion process consists of three stages:

Discretization,

quantization,

Coding.

Discretization- Reading the amplitude of the electric signal after equal intervals of an hour (period). The final stage of signal conversion is characterized by the sampling rate.

Quantization- the whole process of submitting the results of discretization in digital form. The change of the equal of the electric signal for the period of discretization is given in the form of a code word of 8, 10 or 12 bits, which gives 256, 1024 and 4096 quantization equals. According to the number of quantization equals to deposit the accuracy of the detected signal in digital form.

Coding. Crim іnformatsії about zmіnu rіvnya signal, otrimana on the front stage, in the process of coding bits are formed, scho inform about the end of the sync pulse and the beginning of a new frame, as well as additional bits of pardons.

Compression unit webcams compress the digitized video signal into one of the compressing formats (JPEG, MJPEG, MPEG-1/2/4, Wavelet). Zavdyaki squeezing, shortening the expansion of the video frame. It is necessary for the collection and transmission of video from the media. If the network is local, before the webcam is connected, if there is a lot of bandwidth, then in order to eliminate the re-routing of the network traffic, it will speed up the communication of the information that is transmitted, either by reducing the frequency of transmission of frames by the measure, or by dividing the frame rate. More formats of compression, like victorious webcams, providing a reasonable compromise between two ways to overcome the problem of transmitting video across media. Today, compressing formats allow digitizing a stream with a large bandwidth of 64 Kb - 2 Mb (with such a smooth bandwidth, video streams can be processed in parallel with other data streams in the links).

Video compression at the webcam can be presented both in hardware and in software. The software implementation of the compression is cheap, it is not very effective when it comes to calculating the number of compression algorithms, especially if you need to watch the video from the webcam in online mode. Therefore, most of the leading manufacturers release webcams with hardware implementation of compression. For example, AXIS Communications' skin-trim camera is equipped with the ARTPEC compression processor, which creates high-quality video compression in the JPEG/MJPEG format.

central processor є webcam calculation core. Vіn zdіisnyuє operations z vivendennja digitized and compressed video, and also vіdpovіdaє vykonannya functions vbudovanogo web server and keruyuchoї programs for webcams.

Interface for Ethernet vykoristovuetsya for connecting a webcam to the Ethernet standard 10/100 Mbit / s.

For a job in a small webcam, you can mother last port to connect the modem and work in the dial-up mode for the daytime local lines. Through the last port, you can also connect to the webcam peripheral.

Flash memory card Allows you to upgrade the webcam's key programs and save the HTML-sides.

RAM serve for the collection of time data, which are generated when viconann keruyuchih programs and scripts. A lot of Internet cameras can be called a video buffer. The whole part of the OZP is reserved for recording the time-lapse of the video frames captured by the webcam. Information in the video buffer is updated cyclically, so. a new frame is recorded as the deputy of the oldest. This function is necessary, as the webcam monitors the security video warning, the shards allow you to confirm that it is necessary to follow and follow the alarm signal from the security sensors connected to the webcam.

Troublesome enter/exit serve as a connection to the webcam of the alarm sensor. When one of the sensors is used, an alarm signal is generated, as a result of which the webcam processor composes a set of frames recorded in the video buffer before, after and at the moment the alarm occurs. This set of personnel can be sent to a given e-mail address or FTP.

Connecting and installing a webcam

Typically, the webcam is connected to the Internet via a 10BaseT/100BaseTX/1000BaseTX Ethernet port or to a secondary modem via a serial port. After the physical connection of the webcam to the device, IP addresses are assigned. Most webcams don't lock IP addresses; Vіn is installed either for the additional support function of a standard web browser or by a DOS command, as a hack for identification serial number webcam assigned to the virobnik. In addition, virobnik firms are expanding special programs for webcams, to significantly simplify the procedure for assigning an IP address to a webcam (for example, IP Installer from AXIS Communications). Zavdyakovy vbudovanuyu software security for the web server, FTP server, FTP client, e-mail client, etc. the webcam connects directly to the LAN/WAN/Internet network and works in it as an independent network attachment. Do not allow webcams to be connected to other digital cameras, as they require language connection until personal computer via USB chi LPT port. In addition, webcams can support the work with core scripts and JAVA applets.

To install a webcam on the street or in a large variety of places, the camera body is specially attached to the structure, it is recommended for installation on walls, steles, brackets and rotary attachments. Webcams can be built in rotary extensions for mounting on a horizontal or vertical surface.

Additional features and functionality of the webcam

ruhu detector - this is a software module, the main task of which is to display a webcam that moves in the field of light, on the video warning object. The motion detector not only detects the movement in the image field, but also determines the dimensions of the object and the speed of the motion. Falsely watching the video warning, the webcam's rumble detector is set to detect the movement of objects from the boundary minimization of the pardons (filtering the transition), set the logic of processing the alarms (alarming records, other integrations).

Audio signal transmission as far as possible in the majority of cases, it is necessary to connect to the webcam for the account advanced audio module. For example, AXIS Communications for expansion functionality Webcams are produced by a special audio module AXIS 2191, in combination with more AXIS webcams.

Password protector serve to provide access to the webcam by persons who do not have access rights.

For promotional videos from the webcam, you can watch everything lace computer, on which a standard web browser is installed, for example, Internet Explorer or Netscape Navigator. However, you can get as many as you want with access rights to the webcam by entering the password on the koristuvach's account. A lot of webcams support a lot of password protection for delimiting access rights and administration.

webcam software

Typically, webcam images can be viewed using a standard web browser, such as Internet Explorer or Netscape Navigator. However, a lot of publishing companies distribute exclusive programs for webcams.

They combine the functions of a web browser and the necessary software and serve to fix, improve the image review from a webcam (for example, AXIS Camera Explorer or the JVC Professional company's program for administering V.networks lines). Use also software security for roses framing systems a video warning that promotes the possession of various publishers, such as Sphinx-DV from Digicore Systems.

Connecting a webcam to the merezhі

During this time, the webcam can be connected to the cell phone in ways that are based on different data transmission standards.

10/100 Mbit Ethernet. The most popular way to transfer data from a webcam to a cell. There are two standards for 10 Mbit Ethernet: 10Base2 (with different coaxial cable) and 10BaseT (with multiple bet twists). 10Base2 zastosovuetsya rarely through the sensitivity of the coaxial cable to the outer transitions. Standard 100BaseTX VCR twisted couple the security of data transmission is 100 Mbit/s.

1000 Mbit Ethernet, Gigabit Ethernet. The 1000BaseTX standard that is being challenged here is the perfect version of 100BaseTX. This standard zastosovuєtsya is important for stimulating the highways of local merezh.

Standard telephone modems. Cheaper price and access extensions for connecting a webcam to global network. The main disadvantage of this connection method is the low speed of data transmission (the maximum speed of data transmission is 56 kb/s, the maximum speed of data transfer is 33.6 kb/s). Connecting the webcam to the modem is connected via the serial port.

ISDN modems. The ISDN (Integrated Services Digital Network) standard is used to transmit digitized graphics, audio, video information and other digital data over private or global digital telephone measures. The ISDN standard ensures the transmission of data from the webcam on a free basis up to 128 kb/s with two channels.

xDSL modems. DSL (Digital Subscriber Line) is a technology that provides a wide range of transmission with simple medium telephone wires. The speed of data transmission from the webcam may vary depending on the type of company, whatever qiu service. The average won is 1 Mb/s for downloading data and 250 kb/s for downloading.

Cable modems. Cable modem - the same modem, which provides access to the Internet at least cable television. Cable modems use asymmetric technology, which is the most optimal for Internet access. With this, the speed of receiving data from a webcam with such a modem can reach 40 Mb / s (if you want to sound out, do not exceed 1 Mb / s), and the speed of data transfer to become close to 10 Mb / s.

Style modems. For help modem You can connect a webcam to the Internet, vicoristophone lines. The speed of transmission should be set to 5 to 20 kb/s.

More detailed technical information on the specific models webcams from Axis Communications and JVC Professional are presented on the webcam distribution site. short technical characteristics These prices for webcams are shown in the online store of ARMO-Systems.

How to access the webcam via the Internet

How to access the webcam via the Internet

Butt: Since you are already capturing images from the webcam on your computer, you will see that it would be bad for your mother to be able to get to the camera through the Internet. For example, like a manager in a store, you want to control the work in the store from your booth, to replace the need for work at the workplace

Krok 1: System support

Scenario A)

As if your wake-up call (maybe the camera is installed) is already connected via Ethernet to the Internet Service Provider (Internet Service Provider), just connect physical record, add the shared camera to the switch via the shared network, and allow the shared camera to be dynamically assigned to a public IP address. Find the installation commands for the mesh camera. A special program or utility to the webcam will be incorrect in the identification of the IP address.

The recognized IP addresses can be changed by your supplier to the Internet service (through the intermediary delivery of the IP address that is shared among їє clients), you can recognize that you can attach the name of the camera to the IP address you can in Croc4 below.

Scenario B)

If your booth is not equipped with Ethernet access, then in most cases you may need the following add-ons:

wide-range modem for connecting an asymmetric digital subscriber line (which sound is supplied by your Internet service provider) or cable TV

a wide-range router, which can also be called an Internet Gateway, (A wide-range router allows local networks to simultaneously connect to the Internet. It can also serve as an interface between the Internet, the provider of that local network)

switch, which allows small outbuildings interlinking without intermediary one to one and giving the possibility to add-ons from the local network of mothers with IP-addresses),

NOTE: Most wide-width routers may have a switch function, otherwise you don't need it.

mesh camera

local computer

remote watch computer

Lesson 2: Assign an IP address for your camera

A small wide-range router typically assigns automatic, local IP addresses for extensions from a local area, so IP addresses may change authority. Static (permanent) IP addresses are recommended for tethered cameras. To assign a static IP address, find out the range of the router's IP address, which, for example, could be 192.168.0.2 to 192.168.0.35. If you want to change the IP address within a range, such as 192.168.0.100, as a static IP address for the camera, it's safe to assume that your attachments will conflict with other attachments, as they will override automatic addresses.

The set IP address for your camera can be broken in a different way, as indicated in the camera's help. As soon as the IP address is recognized, set the password, and the gateway (this information may be taken from the router), and set the parameters for setting the camera: password, registering the password to secure access to the camera.

Lesson 3: Port Forwarding

A wide-range router, as previously predicted, provides an interface between the Internet, the Provider and the Local Network. The router takes the IP address from the provider of the Internet service and supplies internal (local) IP-addresses for extensions to the local area.

To deny access to the boundary camera, which is permanently located in the local boundary, you must identify the calling IP address of your router (your router's special helper), and configure your router so that the calling IP address is directed to a static, male IP address. merging chamber addresses. This process is named for the port; So if you call the IP address of the router from any networked computer, the Internet will recognize the location of your router, and forward your call to the local IP address assigned to the networked camera.

Launch a web browser and see it on the router's web page via Enter to the router's configuration page.

Find the menu item "port forwarding" (or similar), with a table approximately as shown below:

If the camera overpowers its video over HTTP, you are responsible for configuring the HTTP service in the following way:

Save the configuration at the router and see from the side of the configuration. The config is gone. Any queries that reach the outside IP address of the router on port 80 will be directed by the IP address of the camera: 192.168.0.100.

If you want to make more than one network camera accessible via the Internet, then you are responsible for installing an additional (unofficial) port on the router, type 80xx and linking them with the network IP address of the camera.

Krok 4: What you can know is that your supplier of the Internet service often changes the Dfi call IP address

Create an oblique record with the DNS service as a service and register it domain names(for example www.nic.ru then) and link it to the original IP address. I'm a domain, such as www.web-kamera.ru є ozumіlim coristuvachevі, yogo just remember, and you can recognize the skin domain with your own tassels, tobto. yogo IP address. So, if the IP address of the router is changed, it will be automatically registered with the DNS service, so that you can change your IP address in such a way that you can get to your camera for one and the same address.

Most of the wide range routers can support DNS like www.dyndns.org.

Another alternative: you can buy or rent a static IP address from your provider of the Internet service.

Did you know a friend's pardon? See and press CTRL+Enter

For the help of the webcam, there will be a video warning at the damp booth of the office. For which one chooses the right equipment, we install special software to ensure that the system works perfectly. Let's look at how to choose a webcam for security and organize IP-video-protection, what kind of protection and how problems are blamed on the process.

How to use a webcam

Pratsyuє following the same principle as a digital video camera and photo equipment. The basis is the development of an analog-to-digital converter (ADC), which transforms analog signals that come from a digital sensor into a digital code and formats the color away.

Prompt transfer of the removed data to the computer is allowed by the compression circuit, attached to the USB-interface controller. The rest of the stage is charged for the security and the accuracy of the transmission of the digital code.

Today, IP-video warning has expanded, as if it means transferring data about images from video cameras to a PC for an additional Wi-Fi signal.

Video equipment may have functionality in the form of webcams with HD-separate building pictures, but the base is overstocked:

• transferring data immediately to a computer without recording on a web-cam matrix;
• robot at real time;
• HD-divided image building;
• recording data for the help of special software security for the bajan;
• monitoring of the image from the computer open access to the data.

Have a look special outbuildings for ip-width, install an additional registrar-router with the Wi-Fi function, through which you can exchange data between the camera and the computer.

But the result is the same: the image from the annex (or the annex) is transferred to the PC online, allowing you to watch for the application. Following the same principle, we practice and step behind the help of a standard web-cam connected via a USB port or Wi-Fi.

In both modes, there is a clumsy data storage system that allows access to review recordings or broadcasts from different IP addresses and extensions. Tse web-collection, access to which is subject to the principle of personal physical record, obliges these traditionally occupied and deposited according to the status: paid and cost-free registration.

Programmers of the software for ip-speed to promote the speed of a special gloomy video clip, ale, at a glance z self-improvement only they choose not to surround themselves.

Base for making video warnings:

• computer;
• Webcam;
• special software security;
• dzherelo uninterrupted life;
• access to the Internet.

The main scheme of organization of the guardianship: Web-cam is connected to the computer, a special data registration program is installed, connected gloomy skhovische and everything is password protected.

It’s important to lie: I’ll try to keep a close eye on the rules, so that the image preserves the clarity of the image, hoots a wide hood to look around, for which it’s important to correctly place the camera in the place.

Porada: connect the lifeline of uninterrupted life in order to save crisis situations.

Pluses and minuses

The basis of the organization of the degree is a competent choice I will add. We recommend that you allow cameras to high-rise building images, respect for the speed and type of data transmission.
There are two types of outbuildings:

• digital code transmission via USB module;
• wireless connection for additional Wi-Fi technology.

USB camera. All standard extensions in the low price range, which are connected via cable to the port of the computer extension. Among the models there are basic SD and HD-image clarity, with extended functionality (switching, zoomka in a dark environment, indicator light and others).

For a degree, cameras with a different building size are suitable for 640x528 pixels, but no less. To capture a bright, contrasting and detailed picture, you need to pick up an HD camera.

Tse priority for the step, oskіlki vіd detalіzatsії izobrazhennya to lay the recognition of malice on the record.

• Features: HD-distributed building may cause problems at the stage of setting up a video warning in cost-free program, de-installation of image quality reduction.
• Perevaga: price range on the USB-model is significantly lower, lower without droop;
• Nedoliki: free location of the camera, literally tied with a cable to the computer.

WiFi web cam. The standard range of cameras is higher than the average. From the other side, rozashuvati її it is possible at the apartment or office, in the distance hvil wi-fi. Model range divisions into two categories: for standard wire and for ip-wire.

Another option additional functions: wake-up roo sensors, mode infrared tower for night stance, swivel chamber without additional programs.

Another name for the vision is a merezhna camera, through a personal IP address I will add, until a certain access is granted for encryption keys. The webcam of the local network is connected by analogy with the peripherals. Windows and iOS automatically recognize the camera, but for Linux it is possible to install the driver.

Sound according to the HD settings. Special models are available for installation on the streets: protection against impacts, penetration of water and ultraviolet.

• Features: Wi-Fi technology on the computer is required for connection;
• Perevagi Note: cameras are not tied to the location of the computer, ip-models do not require additional software drivers;
• Nedoliki: the price is higher, lower for the leading models.

Let's take a look at the butt, which functionality of the camera is necessary for the organization of security through a PC.

Webcam Specifications

• Razdіlna building of the sensor. Adds to the clarity of the image, which is important when registering visual data. The fallacy is like this: the more, the more detail of the image, the more details you can see, the face and the text. The minimum for our viewpoint is 680x480 VGA, with a new image readability, and the focus on RAM is not a big deal. For the sake of greater urgency, the central processor of the PC is upgraded, as the speed of data transfer via the Internet is not higher than 20 Mb / s, so it can be allowed. 2GB PC operational memory, two processor cores and more suitable for connecting a web-cam with High Definition to a separate building 1280x720 (abbreviation HD 720p) and more. You can choose and choose, but you can also grow up to the system parameters of the computer. The quality of the video is detailed, contrasting, allowing you to look at the recording of a detailed text and details of the identity of a person.
• Wi-Fi connection. Cameras with a remote installation are suitable for a chained watch: the stench is attached to the point of the premises with a wide view, do not fall into the vіchі and traditionally practice at the retail building starting from 720p.
• Personalized IP addresses. Easier installation of cameras and monitoring of the reception.
• Night tower mode. All standard models operate in the traditional ISO range (light sensitivity) and do not recognize dark images. When the sensor of infra-red vibration detection is put into the camera, it recognizes objects without additional lighting and is suitable for night time. Alternative: get a good webcam for lighting, or organize additional lighting at the place.
• Number of frames per second. The indicator is indicated as FPS, which is greater than the th numerical value, then the greater the quality of the video. The minimum indicator for our vipadku is 40.
• Ruhu sensor. Є in special IP-models for the degree. Allows you to work from a PC not only a video recorder, but also a signaling system in the complex from the installed software.
• Sensitivity of the matrix. Chim over there, while with less light, the camera will be filled with active and coris, continuing to know. Give credit to the LUX display when choosing, give credit to the models with the best display.
• Universal reinforcement. Choose models with handy and similar fixings, which allow you to attach attachments to a computer, furniture, walls, or put them on a flat surface.
• Rib'yache eye function. Okholennya zone revisited at 3600 allows you to fix all the places of the application.
• Attachment of uninterrupted life. If you choose a standard webcam, you need to ensure that your PC works without interruptions. In case of evil, they can use communications, including electricity. DBJ to allow evil to register and send data from the camera to the gloomy server for collecting information.

Yak koristuvatisya

For a competent tweak, use the installation algorithm:

• Designate a monitoring zone for the host. See control points: safe, cash desk, working space and similar. Open the camera so that you can see all the zones at once.
• Connect the camera to a computer or a registrar, depending on the type.
• If the connection is connected through a cable, it is not the fault of the road to become more than 300 m, otherwise waste data and noise is inevitable.
• Spend pervinne nalashtuvannya drivers and software, as it is necessary.
• Get lively, we have a connection to a PC for uninterrupted livelihood.
• Change the connection to the Internet.
• Vikoristovuyuchi standard webcam, install a special program on the PC video warning.
• Adjust the light sensitivity, the number of frames per second, the color profile, the different buildings and the additional functionality (the motion sensor, the infrared vibrance).
• Connect gloomy service video recording of data.
• Reverse the clarity of the image and the speed of transmission of information.

To give respect to the kut I look around that illumination at the host. In case of failure, the security of the supplements is light, we recommend that you take LED lamps to save energy and energy

• Standard webcam with connections via USB-port presented in a low price range. Vykoristovuyut less electricity, do not lie in the supplementary dzherel zhivlennya like a battery. Nedolik - subsoiling of the location.
• Models with wi-fi module ruhlivі, pratsyut at the radius of coverage of the mesh, do not require additional software for connection. Presented at a different building over 720p: the picture is detailed, the contrast is clear. Nedolik - the need for additional equipment such as a router and a registrar.
• IP-cam rozroblenі for stezhennya, vіdіznyayutsya datkovymi funktіonalom yak nіchne bachennya, sensor ruhu and direct zv'yazyok іz server gloomy zberіgannya danih. Control of order in the house at night: when connected to a special software security alarm system, a home alarm will go out.

problems

Typical problem video warning through a standard webcam When the computer is disabled, the session will end.

Folding can be expanded when connected to a PC for uninterrupted living.

The third problem: zlamuvannya danikh. Create the appearance of records in certified programs, IP-models are released from the coded information.

A webcam is an attachment, which is most often bought at the same time with a computer and does not give it a special meaning. Vtіm, pay attention to the characteristics of the varto, otherwise already for the first time, or the session of the call can show up rozcharuvannya that rozdratuvannya.

Dorimuyuchis our pleasures, you can find out everything about the possibilities, functions and areas of webcams. Let's hope that this information will help readers learn correct choice I will attach when buying.

1. What is a webcam, how does it work and de stop

Webcam is enough small annex, which is a photo or video camera, which is connected to a computer or a laptop. Webcams capture images in real time and then force them on the addressee for the help of the Internet. On the view of a digital camera in Persh Cherga, it is in living conditions and impossibility of functioning without a computer, using it completely.

Webcams are installed for video chats and video calls, video conferences, security purposes, for monitoring and warning and other.

1. Main characteristics of webcams

The characteristics of webcams are added as if I’m going to build it, so it’s the same price, as it can vary greatly from model to model. What are the main parameters and what can't you spend an hour choosing a webcam?

• Webcam matrix type. The webcam matrix can be created using the same technology:

a) CCD- a technology that is being developed in digital cameras, as well as being developed for webcams. Middle of the line: high sensitivity, high fill rate, efficiency close to 95%, low overshoot rate when working. Keep in mind that a too weak block of life with great dynamism will come out of harmony at the moment of maximum system involvement, or to wind up її okremih elements. The block of life from a too high pressure can lower the CCD of the entire computer;

b) CMOS- Cheapest technology, which is the most popular in most webcams. Such matrices may have low compatibility, up to 500 frames per second, and can produce little energy when working. In the midst of these shortcomings, experts see a large amount of noise in the image, a low pixel fill factor, and, as a result, low sensitivity;

c) BSI CMOS- when such a matrix is ​​chosen, light is emitted on the photodiode. Such sensors are called "sensors from the back light" - the stench is much more light-sensitive. For a certain amount of noise on the image, it is almost equal to the CMOS loudspeakers.

• Razdіlna zdatnіst kamera- Another one of the most important characteristics. The very sight of it is to lay down the image that is being transmitted. Give respect to the fact that the division of buildings can be direct and interpolated. With software interpolation, the number of pixels in the output image is processed with the help of mathematical methods, multiplied by the same number, and then formed into a larger image. With this cob, the building of the image does not change, but the quality can be improved. When choosing a camera, you should pay attention to the real space in the building at 1.3 megapixels - which is enough for HD-quality.
• Frame rate- Characteristic, scho vіdpovіdaє for the fluency of the catch. The best indicator is the speed of shooting at 15 frames per second - which will be enough for a meeting in Merezh. For the best video broadcasts, at least 30 frames per second is required.
• Focusing The webcam allows you to see the clarity of the image. You can either be manual or automatic. Manually zdіysnyuєtsya wrappers colіshchatka, raztashovanogo bіlа lens. Automatically focusing transmits that the webcam itself sets the focus to the object and restores the focal length. In other models, the speed and brightness of autofocus can be adjusted.
• Sensitivity- the parameter of the minimum allowable illumination, at which it is possible to lighten the camera. At the same time, when buying a camera with infrared light, the characteristic will be immediately presented on the guide line.
• Connection type. Sound webcams are connected via USB version 1.1, 2.0 or 3.0. The rest type is more practical, the prote is less developed on modern computers.

1. Additional functions of webcams:

• The presence of a built-in microphone. Given the need to add one more accessory, it allows you to make video calls with great companies. Today, all cameras are equipped with a built-in microphone.
• Possibility of using a webcam like a camera. Modern models webcams allow you to use them as digital cameras. If you choose a camera for these purposes, give respect to the outbuilding with a larger building, otherwise the number of photographs is unlikely to control you. The cameras are also equipped with a capture button on the body - you can press on to activate the photo mode and launch the graphics editor.
• The presence of special software security. The skin maker of webcams is used by the coristuvachas with the help of the software for the installation or vikoristannya. Crimea standard functions, it can add personal characteristics to the camera robot. For example, Logitech is promoting a graphic editor.

1. What is the next respect?

When choosing and buying a webcam, give respect to the її fastening, the ability to turn around and turn around, and also look around.

Match the characteristics, match the models of webcams, pay attention to our eyes and enjoy the comfortable reception of video-speech.

Today's webcam is a digital accessory that captures video capture, converts analog video signal into digital, compresses digital video signal and transmits video image via computer. The following components are included in the stock of the webcam:

• PZZ-matrix,
• objective,
• optical filter,
• video storage fee,
• video image compression (stiffening) block,
• central processor and wake-up web server,
• flash memory,
• mesh interface,
• aftermath,
• anxious enter/exit.

Like a photo receiver, most webcams get stuck PZZ-matrix (CCD, CCD - attachment from a charge link) - a rectangular, light-sensitive nap_providnikova plate with 3: 4 sides, so that it transforms the light that falls on it into an electric signal. The PZZ-matrix is ​​composed of a large number of light-sensitive centers. In order to increase the light sensitivity of the PZZ-matrix, it is often necessary to form a structure, as if creating a microlens in front of the skin center. For the technical parameters of the webcam, select the format of the PZZ-matrix (the length of the diagonal of the matrix in inches), the number of effective pixels, the type of scaling (row or through streak) and sensitivity.

Lens- a whole lens system, as it is recognized for projecting an image of an object of warning on a light-sensitive element of a webcam. The lens is an invisible part of the webcam, so if the choice is correct, it is installed to store the quality of the video image that is taken by the webcam. Dosit often webcam is equipped with a lens. Objects are characterized by a number of the most important parameters, such as focal length, viewing aperture (F), sharpness depth, mounting type (C, CS), format.

Optical infrared filters, as installed at the webcam, are optically accurate plane-parallel plates that are mounted on the beast of the PZZ-matrix. The stench works like optical low-frequency filters with a frequency of about 700 nm near the red color. The stench is watching the infrared of the storehouse of light fluff, making sure that the webcams are correctly transferred to the colors. Prote, such filters are not installed on rich black-and-white webcams, which is why monochrome webcams can be more sensitive.

Video storage fee webcams (digitizing block) zdіysnyuє conversion of analog electrical signal, formed by PZZ-matrix, digital format. The signal conversion process consists of three stages:

• Discretization,
• quantization,
• Coding.

Discretization- Reading the amplitude of the electric signal after equal intervals of an hour (period). The final stage of signal conversion is characterized by the sampling rate.

Quantization– the whole process of presenting the results of discretization in digital form. The change of the equal of the electric signal for the period of discretization is given in the form of a code word of 8, 10 or 12 bits, which gives 256, 1024 and 4096 quantization equals. According to the number of quantization equals to deposit the accuracy of the detected signal in digital form.

Coding. Crim іnformatsії about zmіnu rіvnya signal, otrimana on the front stage, in the process of coding bits are formed, scho inform about the end of the sync pulse and the beginning of a new frame, as well as additional bits of pardons.

Compression unit webcams compress the digitized video signal into one of the compressing formats (JPEG, MJPEG, MPEG-1/2/4, Wavelet). Zavdyaki squeezing, shortening the expansion of the video frame. It is necessary for the collection and transmission of video from the media.

central processorє webcam calculation core. Vіn zdіisnyuє operations z vivendennja digitized and compressed video, and also vіdpovіdaє vykonannya functions vbudovanogo web server and keruyuchoї programs for webcams.

Interface for Ethernet vykoristovuetsya for connecting a webcam to the Ethernet standard 10/100 Mbit / s.

For a job in a small webcam, you can mother last port to connect the modem and work in the dial-up mode for the availability of the local network. Through the last port, you can also connect to the webcam peripheral.

Flash memory card Allows you to upgrade the webcam's key programs and save the HTML-sides.

RAM serve for the collection of time data, which are generated when viconann keruyuchih programs and scripts. A lot of Internet cameras can be called a video buffer. The whole part of the OZP is reserved for recording the time-lapse of the video frames captured by the webcam.

Troublesome enter/exit serve as a connection to the webcam of the alarm sensor. When one of the sensors is used, an alarm signal is generated, as a result of which the webcam processor composes a set of frames recorded in the video buffer before, after and at the moment the alarm occurs. This set of personnel can be sent to a given e-mail address or FTP.

A professional webcam is a digital video camera or a photo camera, as it allows real-time scanning of images from a webcam and transmitting images over the Internet. To transfer images via the Internet, the program "Instant Messenger" is installed, or another program that allows you to create an image that is transmitted to the video camera.

What is a webcam made up of?

Be it a webcam, it consists of a video camera (CCD matrix), a special compression processor, and also a built-in web server. Today, two types of matrices are available: PZZ matrices and CMOS matrices. Such matrices are enhanced by the level of detail and clarity of the image. Under an hour of work, the webcam will create a video capture and convert the analog signal to a digital signal. The transformation of the digital signal is processed by a special video capture board. After that video can be transferred over the Internet.

Structurally, the warehouse of the video camera includes: PZZ - matrix, optical filter and object, special computer board for video capture, video image compression unit, OZP and central processor, flash memory and wire interface, port for recording with different outbuildings.

PZZ - matrix is ​​a light sensitive conductor. Conductor with a handkerchief, as if transforming light into an electric pulse. Before the warehouse of the PZZ matrix, there is a significant number of light-sensitive middles. For the same reason, due to the number of effective pixels, there is no middle ground for the sensitivity of the PZZ - matrix.

inside webcams with and without lens

The webcam lens is designed to design an image of an object on a PZZ - a computer matrix. The quality of the lens is rich in what lies the quality of the image that is being formed. Some of the key characteristics of the lens are: focal length, lens sharpness depth, format and other technical characteristics of the webcam.

The optical filters of the webcam look like flat parallel sheets. Such dresses are ripped out to the matrix and are recognized for ok transmission to the color of the webcam.

The webcam's video capture card converts an analog electrical signal to a digital format.

Internet compression block - cameras compress video signals. Changing it in volume, converting video signals to such compressing formats as JPEG, MJPEG, MPEG - 1/2/4 or Wavelet. Squeezing the video signal allows the speedy speed of communication of video information for the sake of transparency and transportation of video from the Internet. Use hardware and software to compress video images. Most webcams are released with a hardware constraint, but the most expensive way of squeezing.

For help central processor zdіysnyuyutsya zavdannya shkodo vіdvorennya squeezed and digitized video. Interface - Ethernet is used for connecting a webcam to a local network. When present USB port(wider view) The camera can be connected directly to the computer input.

Optionally, the webcam can replace the web server software. Then it will become an autonomous service, which can be connected without intermediary by koristuvachs via the Internet. In a remarkable way, the camera turns out to be a generator of a video stream, which is processed by a computer and, for additional software, is broadcast to a new installed one.

Advantages and shortcomings of the webcam

The main advantage of a webcam is its mobility and the ability to transmit video information online. The short webcam is to achieve a low image quality and obov'azkovaya nayavnіst broadband connection to the Internet for transmission of images in on-line mode. For excellent record image, broadband access to the Internet is not required.

How does the webcam work?

Once the webcam is connected to the Internet, you will be given a web address. Use special programs to automatically assign the webcam address. When a webcam is designated by a computer, it starts to work like a wire attachment, transforming the image that goes into the lens into a digital signal for recording or transmission to the Internet. In this rank, the webcam robot works.