Analog CCTV cameras usually transmit analog video signals to a Digital Video Recorder via coax cable. Power is supplied to the cameras using a power box, which transmits an electrical signal to the cameras across an RG59 Siamese cable, which also carries the analog video signal. The analog signal is converted to digital by the DVR, compressed, and then stored on the hard drive of the DVR. DVR software is capable of reacting to, and manipulating the digital footage in several ways, including the activation of recording when motion is detected, recording according to a particular schedule, or superimposing a timestamp on the digital footage. Both live and recorded footage can be viewed on the DVR itself, computers connected to the local network, or remote client computers connected over the internet via modem. The video from all cameras connected to the DVR are transmitted as a single stream of data, requiring a single IP address, while conserving bandwidth.
In contrast to Analog CCTV Cameras, IP cameras handle the analog to digital conversion directly. Many are capable of motion detection and compression as well. The converted digital signal is transmitted via Cat5 cabling. IP cameras can be powered just like analog CCTV cameras, or via ethernet cable using Power-Over-Ethernet (POE) adapters. Each IP camera connects to a router or switch, and must be set up individually with an IP address and configurated before use.
In order to view footage from an IP camera, viewing software must be installed on the client computer(s). If the footage is to be recorded, "recording" software must be installed on the computer acting as a DVR. Because different manufacturers use different standards, software and cameras from one manufacturer aren't necessarily compatible with another. This makes incorporating a different IP camera manufacturer into an existing network of IP cameras problematic.
IP cameras are similar to DVRs in that both are capable of transmitting data via the internet. IP cameras, however, use a separate IP address/port for EACH IP camera. Because of this, when more than one camera needs to be viewed on a single screen, "viewing" software must be installed on the client computer. More bandwidth is necessary as well, because of the additional IP addresses per camera.
Which approach is more cost-effective?
For now, the combination of analog cameras with a DVR is the most cost effective surveillance system-----with a few exceptions.
IP Cameras can cost upwards of 5 times the cost of an analog camera. And because analog cameras are available with a wide range of features, it's much easier to find/configure one to fit a particular application.. IP Cameras aren't available in as many configurations as their analog counterparts. In many cases, an analog camera with the perfect set of desired features can be coupled with a video server to "convert" it into an IP camera----often for less than the price of an IP camera with fewer features that are relevant to the application. Despite the fact that a DVR actually isn't required to view IP cameras, in most cases, recording is desired, and requires a more powerful computer than a typical analog camera/DVR setup.
In many cases, the recording software has to be licensed for an additional fee, inflating the cost even more.
While many businesses already have an IP network in place, depending on the number of IP cameras being added, the network may need to be upgraded to support the addition of multiple IP devices. Add in POE adapters, and additional hardware upgrades, and costs can become unwieldy. Bear in mind, however, that some IP cameras also have wireless capabilities, with encryption built-in, which could circumvent some of these issues----depending on the application.
One of the best features of an IP Camera can be it's biggest shortcoming as well. The advent of the "Megapixel" IP Camera is changing the CCTV industry because of the vast amount of data captured within each frame. The downside to this is the vast amount of bandwidth and hard drive space necessary to transmit and record the data. This requires a robust network, a fast internet connection, a powerful computer, and copious amounts of hard drive space. Some IP cameras can use upwards of 60GB of hard drive space per day!
Which approach is better quality?
While analog cameras can only transmit video at resolutions suitable for televisions, IP cameras can exceed this a great deal. The needs of an application have to be assessed in order to determine whether or not the additional data requirements of an IP camera solution are viable both financially and practically. If minor details are important, then it makes sense that an IP camera solution would be considered. IP Cameras also provide a clearer image when objects within the frame are in motion. Applications involving moving vehicles and people could benefit from this feature. Many casinos and police stations use IP cameras, while many small convenience stores opt for analog. In many cases a system comprised of both analog AND IP Cameras serves the best purpose.
Which approach is easier to install and configure?
If an IP network already exists, and enough free ports and bandwidth are available to handle the additional IP Cameras, then IP cameras are easiest to install. Even when the existing network doesn't have enough ports, the addition of a switch is a fairly simply way to add more IP cameras. Analog cameras must have a cable run directly from the camera to the DVR, which can be more cumbersome, depending on the application. Both IP and analog cameras cameras draw power in a similar fashion, piggy-backing on the same cable providing the video signal. However, analog cameras can send a signal approximately triple the distance of IP cameras with no additional hardware (repeater).
Lastly, after physically connecting the cameras, it's much easier to set up a set of analog cameras with a DVR. All analog cameras can be configured from a single screen on the DVR. In contrast, IP cameras have to be configured individually with network addresses and port configurations.
What about wireless?
Wireless IP cameras are superior to their analog counterparts because the wireless signal is digital, which isn't susceptible to interference from everyday appliances and electronics like cell phones and fluorescent lighting. The signal is also encrypted, which prevents unauthorized users from accessing content.
For what applications should I consider IP?
IP cameras are usually appropriate for applications involving an existing network with a lot of bandwidth available---particularly if the cameras will be installed in locations that are relatively far from one another, or even off site. Wireless applications would be a great fit as well.
Bear in mind that a combination of multiple DVRs paired with enough analog cameras to cover the desired area may still be a more affordable and practical solution to an IP camera solution. Many DVRs allow a single computer to merge the video from multiple DVRs onto a single screen, as well as record camera feeds from remote DVRs. Analog camera solutions are less dependent upon networks for recording footage as well. If the network goes down, IP camera footage can't be viewed OR recorded. Analog cameras connected to a DVR will continue to record in the same situation.
For many, the best solution appears to be a system that utilizes analog cameras supplemented with IP Cameras for special applications.
Bullet cameras usually come with a 3.6mm fixed lens which provides a 70 degree angle of view---the widest angle possible without distortion. Up to a distance of about 35 feet, it's possible to see distinguishing facial features. Infrared bullet cameras usually have a viewing distance ranging from 35 to 200ft, depending on the number of LEDs. Cameras with infrared capabilities switch to black and while when illumination falls below a predetermined threshold detected by a light sensor. Footage is captured in color until this threshold is reached. Resolution usually maxes out at 400 lines in infrared mode, while footage captured in color takes full advatange of the camera's maximum resolution.
Internally, there's no difference between bullet cameras, dome cameras, etc. The chassis is designed differently to allow for convenient mounting in applications where a dome or other chassis' wouldn't be ideal. Wall and ceiling mountable, they usually come with a mounting bracket, and 12V DC adapter.
Fixed/Box cameras have removable lenses, making them extremely versatile. To capture footage beyond the 35ft range of the a standard 3.6mm lens, one only needs to change to a lens with a greater focal length (but narrower field of view).
The greater the focal length, the smaller the viewing angle at similar distances. A 16mm lens provides a 15 to 20 degree angle of view at 35ft. In contrast, a 3.6mm lens provides a 70 degree angle of view at the same distance. The correct lens for an application depends on the level of detail necessary, coupled with how far the camera is located in relation to it's target subject.
Varifocal lenses are available, which allow the focal distance to be manually adjusted between 3.6 and 50mm. Angle of view can also be adjusted.
Outdoor camera housings are required when these cameras are used outdoors. Housings are sold separately.
Both C-mount and CS-mount camera lenses can be used with most fixed/box cameras.
|A/V||audio / video|
|AVI||Audio Video Interleave - An audio-video standard designed by Microsoft.|
|AES||auto electronic shutter - the ability of the camera to compensate for moderate light changes by adjusting the camera shutter without the use of auto iris lenses.|
|AGC||automatic gain control - this feature adjusts the brightness level of the video to keep it at a consistent level.|
|BLC||back light compensation - a feature on newer CCD cameras which electronically compensates for high background lighting to give detail which would normally be silhouetted.|
|BNC||Bayonet Nut Coupling - A commonly used connection for audio/video (A/V) applications. Uses a mount similar to the way a bayonet knife is mounted onto the end of a rifle, BNCs are used to connect a variety of different coaxial cable types. After the plug is inserted, it is turned, causing pins in the socket to be pinched into a locking groove on the plug.|
|CAT5||Category 5 (cable) - the type of cable that is used in networking applications.|
|CCD||CCTV security cameras produce images using CMOS or CCD (Charge Couple Device) chips. CCD chips are higher quality and produce a better image than CMOS.|
|CMOS||complementary metal oxide semiconductor - Pronounced see-moss, CMOS is a widely used type of semiconductor.|
|DVR||digital video recorder - a digital video recorder is basically a computer that converts the incoming (analog) signal from the cameras to digital, and compresses it, and stores it. The DVR replaces the function of a multiplexor (or quad or switcher) and a security VCR. There are many advantages of digital video recorders over their analog counterparts.|
|FPS||frames per second - in digital video applications, refers to the number of video images that can be captured, displayed, or recorded in a second. Also referred to as the 'frame rate' or 'refresh rate'.|
|JPEG (or JPG)||Pronounced "jay-peg" and stands for "Joint Photographic Experts Group" who designed the standard. This is a standard way of compressing images which works particularily well for photographic images (as opposed to graphic art).|
|MPEG (or MPG)||Pronounced "em-peg" and stands for "Motion Picture Experts Group" who designed the standard. This is a standard way of compressing audio and video files. (It's also the technology behind the now world-famous MP3 music files.)|
|POE||Power Over Ethernet - an adaptor that allows you to transmit power to a security camera through CAT5 (aka ethernet) cable.|
|PTZ||pan-tilt-zoom - PTZ cameras allow you to adjust the position ('pan' is side-to-side, 'tilt' is up-and-down) and focus ('zoom') of the camera using a remote controller. Due to this added functionality, these cameras tend to cost much more than non-PTZ cameras|
|RG59||An RG-59 is a common coax cable used in CCTV applications.|
|RCA||An RCA connector, sometimes called a phono connector or cinch connector, is a type of electrical connector commonly used to carry audio and video signals. The name "RCA" derives from the Radio Corporation of America, which introduced the design by the early 1940s to allow mono phonograph players to be connected to amplifiers.|
|S/N ratio||signal to noise ratio; this number represents how much signal noise the camera can tolerate and still provide a good picture. The higher the number the better.|
|VCR||Videocassette recorder; an electronic device for recording and playing back video images and sound on a videocassette.|
Glossary of CCTV Terms
|AC adaptor||Also called a power supply. All CCTV devices needs power of some sort. Each device has its own power requirements (usually 12 volts with a minimum amperage). The power coming out of the wall (in the US) is 110 to 120 AC. The adaptor converts the AC power to DC power and will adjust it to a specified amperage. The power supply should be included with each item - you usually don't have to buy these separately.|
|alarm input||An input connection to a security VCR or DVR that triggers the unit to start recording if the alarm is triggered.|
|analog||There are two main ways of doing things electronically, analog or digital. An analog signal can be represented as a series of sine waves. The term originated because the modulation of the carrier wave is analogous to the fluctuations of the human voice or other sound that is being transmitted.|
|analog system||Most cameras used in cctv applications are analog. Security VCRs, switchers, multiplexors and quads also are analog devices. Any cctv system that consists of analog devices are considered analog systems. Compare to 'digital systems'.|
|angle of view||For security cameras, this refers to the angular range in degrees that you can focus the camera on without distorting the image. When focusing close up, you can generally see a wide angle of view. If the focus is distant, the angle of view is smaller or narrower.|
|aperture||The opening of a lens which controls the amount of light let into the camera. The size of the aperture is controlled by the iris adjustment and measured by an f-number. The higher the f number the less light is permitted to pass into the camera. For example, a f1.2 lens will allow more light to reach the sensor and produce a brighter image than an f2.0 lens.|
|armor dome camera||These cameras are designed to resist vandalism by using a hi-impact reinforced polycarbonate dome casing.|
|audio||Most cameras capture 'video' only (what you can see) - some come with audio too (sound). You can add a microphone to a security system to capture audio if needed. To record the sound, your recording device needs to support audio (must have at least one audio input).|
|auto electronic shutter (AES)||The ability of the camera to compensate for moderate light changes in indoor applications without the use of auto iris lenses.|
|auto iris control||A lens in which the aperture automatically opens or closes to maintain proper light levels on the faceplate of the camera pickup device.|
|auto gain control (AGC)||An electronic circuit used by which the gain of a signal is automatically adjusted as a function of its input or other specified parameter.|
|auto white balance||A feature on color cameras that constantly monitors the light and adjusts its color to maintain white areas.|
|back light compensation (BLC)||A feature on newer CCD cameras which electronically compensates for high background lighting to give detail which would normally be silhouetted.|
|bullet camera||A type of camera with a bullet like shape. Can be used inside or out. Some come with infrared lighting.|
|c-mount camera||C-Mount and cs-mount cameras are designed to accomodate custom lenses. The lenses can be removed and replaced. Both c-mount and cs-mount cameras have a thread with a 1 inch diameter and 32 threads per inch. The difference between them is that c-mount cameras have a distance from the lens mounting surface to the camera sensor of 0.69 inches whereas the cs-mount distance is 0.492 inches. Is is possible to put a c-mount lens on a cs-mount camera by using a CS adaptor ring. But you cannot put a cs-mount lens on a c-mount camera.|
|cable||The wiring used to connect electronic devices. Cables tranmit different kinds of signals such as video, power, data, and audio signals. Refer to plug and play cable and RG59 siamese cable for more information.|
|camera sensor||Also known as "camera pickup device", "image sensor", or "CCD". These are all names for the CCD sensor in the camera that actually senses or captures the image.|
|ccd||Stands for "charge-coupled device". First invented in the 1970s, this technology uses a shift register combined with photodiodes to create the modern day imaging device. Used in cameras, scanners, fax machines, etc. The size of the CCD chip is normally 1/4", 1/3" or 1/2". As a rule of thumb, the larger the size, the higher the quality of the image produced and the higher the price. However some of the higher density 1/4" and 1/3" CCD chips can now produce as good an image as many of the 1/3" or 1/2" chips.|
|compression||Refers to taking an incoming signal or image, which can be analog or digital, and compressing the data so it can be stored or transmitted faster and using less resources. There are many different algorithms and techniques that are used to compress data.|
|covert||A covert application refers to a situation where you don't want the person to know that they are being watched or recorded. Also known as 'hidden' cameras.|
|cs-mount camera||C-Mount cameras are designed to accomodate custom lenses. The lenses can be removed and replaced.|
|day / night camera||"Day/Night Cameras" are regular cameras with an especially sensitive CCD chip that allows a good image to be captured in very low ambient lighting (regular lighting - not infrared). Do not confuse these cameras with "Night Vision" cameras which is another name for infrared cameras.|
|digital||There are two main ways of doing things electronically, analog or digital. The digital method is to consider a circuit either on or off. A digital voltage or signal refers to the discrete nature of digital voltage potentials in digital circuits. TTL (Bipolar Transistor-Transistor Logic) defines 0.0 Volts as a logic 0 or low, and 5.0 Volts as a logic 1 or high; These are single values for clarity - there are actually ranges of voltage potentials around 0.0V and 5.0V which are recognized as low and high logic levels, respectively.|
|digital system||CCTV systems are just lately coming into the digital age. Most security cameras are still analog. There are some digital cameras available but they are extremely expensive. Where digital technology is really making ground in CCTV is with digital video recorders (or DVRs). Any CCTV system that includes a DVR is considered a digital system.|
|digital video recorder (DVR)||A digital video recorder is basically a computer that converts the incoming (analog) signal from the cameras to digital, and compresses it, and stores it. The DVR replaces the function of a multiplexor (or quad or switcher) and a security VCR. There are many advantages of digital video recorders over their analog counterparts.|
|dome camera||A type of camera with a dome like shape. Usually used inside only. Some come with infrared lighting and some are designed to be tamper-proof.|
|duplex||A duplex device can transmit data into and out of the electronic device at the same time. For example, a full duplex modem can send and receive data at the same time.|
|duplex DVR||A duplex DVR is a DVR that can record and view/playback at the same time. Compare to a triplex DVR or a pentaplex DVR.|
|frames per second (FPS)||In digital video applications, refers to the number of video images that can be captured, displayed, or recorded in a second. Also referred to as the 'frame rate' or 'refresh rate'.|
|housing||Special covering or container to protect a camera from extreme temperatures or weather conditions.|
|infrared||The region of the electromagnetic spectrum bounded by the long-wavelength extreme of the visible spectrum (approximately 0.7 m) and the shortest microwaves (approximately 0.1 mm).|
|infrared camera||Infrared cameras (aka night vision cameras) have special infrared lights installed around the perimeter of the camera lens. This provides special light that the camera uses to capture a good picture even in total darkness.|
|iris||The iris (on some lenses) controls how much light is let into the camera lens.|
|jpeg (or jpg)||Pronounced "jay-peg" and stands for "Joint Photographic Experts Group" who designed the standard. This is a standard way of compressing images which works particularily well for photographic images (as opposed to graphic art).|
|lens||The lens of the camera determines the angle of view and the focus of the captured image. There are many different lens options.|
|low light||Refers to very dim lighting, even 'normal' darkness. Complete darkness is 0 lux. Infrared cameras work well in very low light conditions.|
|lux||Refers to the amount of light required for a camera to capture a good image. Infrared cameras have very low lux.|
|micro camera||Very small cameras designed to work in covert applications where you don't want people to know that the camera is there. Also called 'hidden cameras'.|
|monitor||Security monitors are used to display the images from your cameras (or captured on your recording device). There are two basic kinds used today in CCTV applications. Analog or composite video monitors are used to display images in analog systems. They are just like a TV screen without the TV receiver. These are the monitors we have for sale on our site. Digital or VGA monitors (just like on your computer) are used with digital devices like the Digital Video Recorders. We don't include the monitor with our digital video recorders because you can pick one up more affordably at your local computer store (and not have to pay the shipping cost for such a heavy item).|
|motion detection||Refers to the feature in some VCRs and DVRs to only record video if something in the image moves or changes. Therefore you don't have to look through hours of taped video looking for something to happen. It also saves a lot of space on the tape or hard drive.|
|mounting bracket||Various different kinds of mounting brackets are used to install cameras to the wall or ceiling.|
|mpeg (or mpg)||Pronounced "em-peg" and stands for "Motion Picture Experts Group" who designed the standard. This is a standard way of compressing audio and video files. (It's also the technology behind the now world-famous MP3 music files.)|
|multiplexor||A device that can accept a number of camera inputs and almost simultaneously display them on a single monitor and/or record them. Multixplexers can also be used to transmit multiple cameras over the same transmission medium.|
|outdoor camera||Outdoor cameras come in special weatherproof housings that allow them to stand up well in tough weather and temperature conditions.|
|pan-tilt-zoom (PTZ) cameras||PTZ cameras allow you to adjust the position ('pan' is side-to-side, 'tilt' is up-and-down) and focus ('zoom') of the camera using a remote controller. Due to this added functionality, these cameras tend to cost much more than non-PTZ cameras|
|pentaplex or pentaplex DVR||A pentaplex DVR is a DVR that can perform all the DVR functions at the same time: record, view/playback, network (view remotely), administrate and backup. For example, a machine that is notpentaplex would stop recording while the administration functions were being performed. Compare to a duplex DVR or a triplex DVR.|
|pin-hole camera||Pin-hole cameras have a very small lens that can see through a small hole. These types of cameras are used in covert applications. A disadvantage of pin-hole cameras is that they require more lighting than normal cameras to capture a good clear picture.|
|plug and play cable||A cable that makes wiring cameras easy. Each camera needs to have a power wire and video wire (and sometimes an audio wire too), plus the connectors at the end of the wire to plug it in. The plug and play cables have all three wires built into one cable with the connectors already attached. The only disadvantage of plug and play cable is that the signal tends to degrade if run distances. For DVRs - plug and play cables can be run reliably up to 100 ft. For analog systems - plug and play cable can be run up to 400 ft. If you need to run longer distances then you need to use the RG59 siamese cable.|
|power supply||Also called an AC adaptor. All cctv devices needs power of some sort. Each device has its own power requirements (usually 12 volts with a minimum amperage). The power coming out of the wall (in the US) is 110 to 120 AC. The power supply converts the AC power to DC power and will adjust it to a specified amperage. The power supply should be included with each item - you don't have to buy these separately.|
|quad||An analog device used to display 4 cameras simultaneously on a single monitor.|
|RG59 siamese cable||This type of cable combines the power wire with the video wire. You have to add your own connectors to each end of the cable. Use this type of cable when you need to run distances longer than 100 ft with a digital system, or more than 400 ft. with an analog system (see the plug and play cable above). The RG59 siamese cable can be run reliably up to 1000 ft.|
|real-time recording||In digital video applications, 30 frames per second per camera (see above) looks just like real-time. There is no hesitation or jerkiness in the video.|
|remote surveillance||The ability to view your cameras from a remote location. Information is transmitted via phone line or internet.|
|resolution||Refers to how much detail can be captured on a camera or displayed on a monitor. Cameras typically capture about 380 horizontal lines of resolution. High resolution cameras may capture 450 lines of resolution or more. The higher the resolution, the more detail that can be captured in a picture. The monitors and recording devices can generally handle at least as much resolution as the cameras can capture.|
|Smart Search||This is a feature of our digital video recorders that allows you to search for changes in a particular area of an image over time. For example, if a wallet was stolen off of a table, you could go to a point on the video where the wallet is there, draw a virtual box around that area, then search the video recording for changes to that particular area. This would allow you to locate the exact point on the video where the wallet was removed.|
|s/n ration||signal to noise ratio; this number represents how much signal noise the camera can tolerate and still provide a good picture. The higher the number the better.|
|switch||A switch will take multiple camera inputs and will show them on the monitor one at a time. Unlike a quad it will not display them all at once, instead it sequences through them showing one camera at a time. It will also allow you to select a particular camera to view.|
|time-lapse VCR||A VCR that can be set to slow down its recording rate in order to extend the length of time that can be recorded on a standard tape up to as much as 960 hours. This is possible by recording one frame at time at set time intervals. Most units have an alarm input signal so it can be automatically switched to real time mode in case of an alarm.|
|transformer||A device used to transfer electric energy from one circuit to another, especially a pair of multiply wound, inductively coupled wire coils that effect such a transfer with a change in voltage, current, phase, or other electric characteristic.|
|triplex or triplex DVR||A triplex DVR is a DVR that can record, view/playback, and network (view remotely) at the same time. Keep in mind that manufacturers may use this term differently so check for details on the product. Compare to a duplex DVR or a pentaplex DVR.|
|varifocal lens||A camera lens in which the focus is not fixed, it can be manually or automatically adjusted.|
|VCR||Videocassette recorder; an electronic device for recording and playing back video images and sound on a videocassette.|
|video capture card||Computer cards that you can install on the motherboard of your own computer to create your own video recording computer. Due to compatibility issues with this type of device, we do not sell these separately.|
|video gain||An increase in video signal power by an amplifier, expressed as the ratio of output to input. Also called amplification.|
|video input||A connection in a video controller or recording device that you can plug a camera into. The more video inputs (also called camera inputs) available on a device the more cameras you can connect to it.|
|watch dog timer circuit protection||If problems are detected in the DVR computer the system will automatically reboot to correct the problem.|
|waterproof||A device that can be immersed in water and still function properly.|
|weatherproof||A device that is weatherproof can be installed outside and stand up to harsh weather conditions and temperatures. However, it does not mean that it is waterproof.|
|wireless camera||Wireless cameras allow the transmission of video and audio data to be transmitted to the receiver without having to run wires (using radiowaves).|
DIGITAL VIDEO RECORD FAQ
What features should I look for in a Digital Video Recorder (DVR)?
When choosing the correct DVR for an application, several features should be considered. The number of cameras supported, frame rate, compression standard, hard drive space, network connectivity, remote viewing capabilities, motion detection, scheduled record, and backup capabilities. Audio and smart-search capabilities are also worth learning more about.
What is frame rate (fps)?
This refers to the number of images the DVR records in a single second. Real-time recording is 30 frames per second, and captures the most detail in relation to moving objects. For applications where there's a lot of movement, and details are imperative, 30fps is a great choice. However, real-time recording uses up a lot of hard drive space. Approximatley double that of a system set to record 15fps----which is the best compromise between quality and hard drive space. Most users will record at this rate. The video is still fluid, and half the hard drive space is used.
Which hard drive size do I need?
Hard drive capacity determines how much video a DVR can record before it has to start recording over it's oldest footage. Recording resolution, frame rate, compression standard, and number of cameras all contribute to hard drive usage. Reducing frame rate and opting for scheduled recording or motion recording, can really conserve hard drive space.
What's the difference between a Standalone and a PC Based DVR Server?
A PC based DVR is a personal computer with DVR software and hardware installed that allows it to function as a digital video recorder. A standalone is a device that ONLY performs DVR functions. Standalones are usually much more affordable than their PC based counterparts, because fewer components are necessary to build them. The compromise is that many standalones are not at powerful as PC based DVRs, and often have fewer features.
Standalones are starting to close this gap in features, however. A PC based DVR is vulnerable to the same problems that plague any PC----viruses, instability, etc----none of which, for the most part, exist with standalone DVRs. If a standalone has most of the features necessary for an application, it should be considered a strong contender for getting the job done.
How does a Digital Video Recorder work?
A DVR is a device that records surveillance footage to a hard drive. When necessary, the DVR will convert an analog signal ito a digital one, compress it, then record it to a hard drive..
DVRs can record footage from up to 64 cameras----all at the same time---depending on the type of DVR. Most DVRs come with a software based interface that allows the viewer to see the footage from all cameras at a glance----or one at a time.
Are DVRs difficult to install?
No. Plug in cameras, a monitor, a keyboard and a mouse, and you're ready to go. Most PC based DVRs are designed to launch the DVR software when the PC is powered on.
What comes with the DVR?
Mammoth Technologies DVRs come with all the hardware and software necessary to start recording. PC based systems come with keyboard, mouse, software and hardware pre-installed, and instructions. Just add a computer monitor and CCTV cameras.
Why doesn't the computer monitor come with PC based DVRs?
We offer several packages that DO come with monitors. Many customers already own computer monitors, making them unecessary for many. If you'd like a monitor with your DVR, feel free to give us a call, and we can provide one for an additional fee.
How do I view footage remotely?
All of our DVRs can be viewed remotely via Internet Explorer. Depending on the DVR, remote viewing is also possible via iPhone, Blackberry, Windows Mobile, Android, and Sarari & Firefox browsers. Basic viewing is usually possible with nothing more than the DVR IP address, a username, and a password. Installation of client software usually gives the user access to more features.
The DVR itself has to be connected to the internet or LAN via router, and configured with a static IP address for remote access.
What is "Smart Search"?
Smart search allows the user to highlight a specific area onscreen, and the DVR software will fast-forward or fast-rewind to the point in time when any changes occurred in the highlighted section. For instance, if a purse is on camera, but turns up missing, the user could go back to the point in time when the purse was still visible, activate smart search, highlight the area around the purse, and the software will "jump" to any locations in the timeline involving any changes to the highlighted area.
Should I purchase the DVR Card from you and build a DVR myself?
Not necessarily. Our DVRs are thouroughly tested before they ship out. We guarantee all of our components will work properly with the pre-installed software and hardware. We've already found hardware---RAM, motherboard, hard drive, chassis, video card, etc-----that we warranty for a full 3 years (PC based DVRs). We can't make this same guarantee for third party components purchased elsewhere.
Dome cameras are available in many configurations. They can be mounted on walls or ceilings, used indoors or outdoors, and capture footage in complete darkness, depending on the configuration. Many come with adjustable varifocal lenses, in a variety of resolutions.
All of our dome cameras come with Sony CCDs, with most basic models shipping with a 3.6mm lens.
Some of our most flexible dome cameras come in configurations that can include infrared LEDs for recording footage in complete darkness, vandal-proof chassis to prevent unwanted tampering, and varifocal lens for adjusting the focal length based on application. All of our dome cameras come with mounting bracket and 12V DC adapter.
Infrared cameras use a series of Light Emitting Diodes (LEDs) from a portion of the electromagnetic spectrum that's invisible to humans. Infrared cameras can use the light from their LEDs to capture an image and convert it into one that's visible to humans. Infrared cameras are perfect for applications involving low light or night-time.
While often referred to as "Night Vision" cameras, please be aware that these cameras are not the same as those with a "Day/Night" distinction. "Day/Night" cameras do not have LEDs, and require a light source to capture an image, albeit a "low light" source. Day/Night cameras measure capture capability in "lux". The lower the lux number, the better the camera can "see" in low light. Infrared cameras can work in complete darkness, and therefore have a lux of "0".
Infrared cameras capture footage without LEDs when sufficient light is available. When the light level falls below a certain threshold, a sensor activates the LEDs, and the camera will capture footage in black and white. The number of LEDs affects the distance an infrared camera is capable of capturing footage from. The more LEDs, the further away the camera can "see." The range is usually anywhere from 40ft to several hundred feet.
Infrared cameras come in both bullet and dome configurations, as well as indoor/outdoor and vandal-proof option. A 12V DC adapter is provided.
What is a Pre-Made cable?
Pre-Made cables come in pre-configured lengths, usually in multiples of 25ft, and have video and power connectors already attached on both ends. RG59 cable usually comes in a spool, allowing the user to cut cable in custom lengths. The video and power connectors must be connected manually.
When should I use RG59 instead of Pre-Made?
For cable runs under 100ft, pre-made cables do a great job. For lengths over 100ft, RG59 is superior. RG59 has more shielding than pre-made cables, to prevent distortion and intererence across greater distances. We carry spools of RG59 cable in a length of 500ft. BNC and power connectors are also available separately.
RG59 Spool Instructions
How attach a RG59 Twist-On connector to a RG59 Cable
How to install Power Connector or RG59 Cable
How to connect a Siamese Cable to a Power Box
Which lens should I use?
For starters, remember that separate lenses are only available for fixed/box cameras.
Distance and detail determine the correct CCTV lens for different applications. There is an inverse relationship between focal length and angle of view----the lower the focal length, the greater the field of view. For example, a 4mm lens yields a 70 degree angle of view at 35 feet. A 16mm lens, on the other hand, yields a 15 degree angle of view at the same distance. The greater the distance the lens needs to "see," the smaller the viewing angle.
Click HERE to use our online lens tool to help you choose the correct lens for your application.
What if I don't know how far away I need to see?
CCTV lenses are available with "variable-focus" or "varifocal" lenses, allowing the user to adjust the focal length manually and zoom in or zoom out for different applications. These lenses are more expensive than their "fixed" counterparts, but are capable of providing a perfect fit for many applications that involve focusing on a subject that falls in between focal lengths available in fixed lenses.
What is a PTZ camera?
PTZ stands for "Pan, Tilt, and Zoom." A PTZ camera allows a user to adjust all three from a DVR or separate controller. While PTZ cameras provide the ultimate in viewing versatility, they are larger, more expensive, and use more mechanical parts than other CCTV cameras. However, PTZ cameras often have capabilities that greatly distinguish them from regular CCTV camera. "Auto-tracking" is such a feature. A PTZ camera can be programmed to detect movement, and FOLLOW it. It can also be programmed to scan an area, touching upon pre-programmed "spots", in a cycle. The pan, tilt, zoom abilities allow users to target a subject with a level of detail unavailable on normal CCTV cameras. PTZ cameras are usually reserved for applications with special surveillance needs, often with target areas that don't remain static.
What is the difference between "no iris" and "auto iris"?
The iris controls the amount of light allowed into a CCTV lens. Older lenses had no iris control, and users had to purchase special lenses with manual controls for extreme light applications. Current CCTV lenses come with this function built in, allowing the shutter (as opposed to the iris) to automatically open and allow in more light in low light situations. This is usually sufficient. However, for application involving cameras in locations with extreme light levels, (bright sunlight, for example), a lens with an auto-iris would be ideal..
What is a wireless CCTV camera?
A wireless CCTV camera transmits a video signal wirelessly rather than via cable. They are regular CCTV cameras with a wireless transmitter installed that send a signal wirelessly to a receiver connected to a DVR or monitor.
Is there a difference between analog and digital wireless cameras?
Digital wireless CCTV cameras are superior to their analog counterparts because the wireless signal is digital, which isn't susceptible to interference from everyday appliances and electronics like cell phones and fluorescent lighting. The signal is also encrypted, which prevents unauthorized users from accessing content. Digital wireless CCTV uses the 802.11x standard, whis is the same standard used by wireless routers.
A standard CCTV camera can be converted into a wireless one by using a netork video server coupled with a wireless IP bridge. The best solution depends on a compromise between cost, features, and distance.
VIDEO COMPRESSION STANDARDS
Most video compression is lossy: it operates on the premise that much of the data present before compression is not necessary for achieving good perceptual quality. For example, DVDs use a video coding standard called MPEG-2 that can compress video data by 15 to 30 times, while still producing a picture quality that is generally considered high-quality for standard-definition video. Video compression is a tradeoff between disk space, video quality, and the cost of hardware required to decompress the video in a reasonable time. However, if the video is overcompressed in a lossy manner, visible (and sometimes distracting) artifacts can appear.
Video compression typically operates on square-shaped groups of neighboring pixels, often called macroblocks. These pixel groups or blocks of pixels are compared from one frame to the next and the video compression codec (encode/decode scheme) sends only the differences within those blocks. This works extremely well if the video has no motion. A still frame of text, for example, can be repeated with very little transmitted data. In areas of video with more motion, more pixels change from one frame to the next. When more pixels change, the video compression scheme must send more data to keep up with the larger number of pixels that are changing. If the video content includes an explosion, flames, a flock of thousands of birds, or any other image with a great deal of high-frequency detail, the quality will decrease, or the variable bitrate must be increased to render this added information with the same level of detail.
|MPEG||Stands for the Moving Picture Experts Group MPEG is an ISO/IEC working group, established in 1988 to develop standards for digital audio and video formats. There are five MPEG standards being used or in development. Each compression standard was designed with a specific application and bit rate in mind, although MPEG compression scales well with increased bit rates.|
|MPEG-1||Designed for up to 1.5 Mbit/sec
Standard for the compression of moving pictures and audio. This was based on CD-ROM video applications, and is a popular standard for video on the Internet, transmitted as .mpg files. In addition, level 3 of MPEG-1 is the most popular standard for digital compression of audio--known as MP3. MPEG-1 is the standard of compression for VideoCD, the most popular video distribution format thoughout much of Asia .
|MPEG-2||Designed for between 1.5 and 15 Mbit/sec
Standard on which Digital Television set top boxes and DVD compression is based. It is based on MPEG-1, but designed for the compression and transmission of digital broadcast television. The most significant enhancement from MPEG-1 is its ability to efficiently compress interlaced video. MPEG-2 scales well to HDTV resolution and bit rates, obviating the need for an MPEG-3.
|MPEG-4||Standard for multimedia and Web compression. MPEG-4 is based on object-based compression, similar in nature to the Virtual Reality Modeling Language. Individual objects within a scene are tracked separately and compressed together to create an MPEG4 file. This results in very efficient compression that is very scalable, from low bit rates to very high. It also allows developers to control objects independently in a scene, and therefore introduce interactivity.|
|MPEG-7||This standard, currently under development, is also called the Multimedia Content Description Interface. When released, the group hopes the standard will provide a framework for multimedia content that will include information on content manipulation, filtering and personalization, as well as the integrity and security of the content. Contrary to the previous MPEG standards, which described actual content, MPEG-7 will represent information about the content.|
|MPEG-21||Work on this standard, also called the Multimedia Framework, has just begun. MPEG-21 will attempt to describe the elements needed to build an infrastructure for the delivery and consumption of multimedia content, and how they will relate to each other.|
|JPEG||Stands for Joint Photographic Experts Group. It is also an ISO/IEC working group, but works to build standards for continuous tone image coding. JPEG is a lossy compression technique used for full-color or gray-scale images, by exploiting the fact that the human eye will not notice small color changes.|
|JPEG 2000||An initiative that will provide an image coding system using compression techniques based on the use of wavelet technology.|
|DV||A high-resolution digital video format used with video cameras and camcorders. The standard uses DCT to compress the pixel data and is a form of lossy compression. The resulting video stream is transferred from the recording device via FireWire (IEEE 1394), a high-speed serial bus capable of transferring data up to 50 MB/sec.|
|H.261||An ITU standard designed for two-way communication over ISDN lines (video conferencing) and supports data rates which are multiples of 64Kbit/s. The algorithm is based on DCT and can be implemented in hardware or software and uses intraframe and interframe compression. H.261 supports CIF and QCIF resolutions.|
|H.263||Based on H.261 with enhancements that improve video quality over modems. It supportsCIF, QCIF, SQCIF, 4CIF and 16CIF resolutions.|
|H.264||H.264, also known as MPEG-4 AVC (Advanced Video Coding), is a video compression standard that offers significantly greater compression than its predecessors. The standard offers up to twice the compression of the current MPEG-4 ASP (Advanced Simple Profile), in addition to improvements in perceptual quality. The H.264 standard can provide DVD-quality video at under 1 Mbps, and is optional for full-motion video over wireless, satellite, and ADSL Internet connections.|
|DivX Compression||DivX is a software application that uses the MPEG-4 standard to compress digital video, so it can be downloaded over a DSL/cable modem connection in a relatively short time with no reduced visual quality. The latest version of the codec, DivX 4.0, is being developed jointly by DivXNetworks and the open source community. DivX works on Windows 98, ME, 2000, CE, Mac and Linux.|
|Terms||Lossy compression - reduces a file by permanently eliminating certain redundant information, so that even when the file is uncompressed, only a part of the original information is still there.|
International Organization for Standardization - a non-governmental organization that works to promote the development of standardization to facilitate the international exchange of goods and services and spur worldwide intellectual, scientific, technological and economic activity.
International Electrotechnical Commission - international standards and assessment body for the fields of electrotechnology
Codec - A video codec is software that can compress a video source (encoding) as well as play compressed video (decompress).
CIF - Common Intermediate Format - a set of standard video formats used in videoconferencing, defined by their resolution. The original CIF is also known as Full CIF (FCIF).
QCIF - Quarter CIF (resolution 176x144)
DIGITAL VS. ANALOG
|Long cumbersome manual search to retrieve footage||Instantly search by date, time, or event|
|Requirement to purchase videotapes||Store months of footage at no additional cost|
|Video signal degradation on re-recording or duplication||No signal or quality loss on recording|
|Risk of lost data with failure to change tapes or record||Automatically overwrites oldest video footage|
|Poor image quality||Digital images are much higher quality|
|Inflexible configurations and settings||Flexible configurations and settings|
|Limited remote monitoring ability||Remotely view multiple locations from anywhere|
|Lack of redundant off-premises recording capability||Record video off-premises to a remote server|
|Low storage capacity||High storage capacity|
|Limited security||Multiple levels of user security|
|No intelligence||Intelligent features (motion detection, remote notification)|