Frequently Asked Questions:
What is a network camera?
A network/IP camera can be described as a camera and computer combined in one unit. It captures and transmits live images directly over an IP network, enabling authorized users to locally or remotely view, store, and manage video over standard IP-based network infrastructure.
What is the difference between a web camera and an IP camera?A web camera is connected to a PC, normally through USB, and uses the PC to make video available to other viewers. It will not work without a PC locally connected to the camera. An IP or network/IP camera usually stands alone, and combines the functionality of a high-end web camera, the PC and network interface into one network-ready product.
How much bandwidth does an IP Camera need?It depends on both the resolution and frame rate. It also depends on the compression technology the network/IP camera is using.
Below are three of the most popular compression technology and the required bandwidth and other important information.
Compression Protocol M-JPEG MPEG-2
MPEG-4
Compression Rate
6
30-40
200-500
Resolution
352 x 288
720 x 576
720 x 576
FPS
25-30 fps
50-60 fps
25-30 fps
Bandwidth Required
1.5Mbps
4-15Mbps
10K-1Mbps
Also, please note that 30 frames/s (NTSC) is the required frame rate to provide continuous motion and good quality (DVD like) video.
What's the advantage using MPEG-4?MPEG-4 provides DVD quality video, but uses lower bit rate than MPEG or MPEG-2. This lower bit rate makes it's feasible to transmit digitized video streams in LAN, and also in WAN, where bandwidth is more critical, and hard to guarantee.
What are Common Applications for CCTV camera ?Probably the most widely known use of CCTV camera is in security systems and such applications as retail shops, banks, government establishments, etc. The true scope for applications is almost unlimited. Some examples are listed below.
- Security Applications
- Observe and record theft or violence by overtly monitoring retail floor space, office buildings, building perimeters, warehouses, loading docks and parking garages.
- Monitor sensitive areas where infrequent activities occur (i.e. confidential records, safes, etc...)
- Monitor point-of-sale exceptions (cash register voids, over-rings, etc...) reducing cashier theft.
- Observe and record shoplifting activities.
- "Walk a beat" by programming a moving camera to pan, tilt, and zoom within a defined pattern.
- Perform covert surveillance (where legally applicable)
- Integrate with access control systems to provide video of persons entering and leaving the premises
- Complement asset tracking systems to provide video when a tagged asset leaves the premises. Loss prevention is the #1 concern for retailers. Inventory “shrinkage” - through a combination of employee theft, shoplifting, vendor fraud and administrative error - is one of the fastest growing expenses in retailing today. According to a National Retail Security Survey, inventory shrinkage cost U.S. retailers more than $32 billion in 2000.
- Monitor Financial Institutions- According to FBI data reported by the American Bankers Association - Bank robberies in the United Sates totaled 8,259 in 2001. Washington State alone averaged a robbery a day, and claimed losses of $1.1 million in 2001. Account, check, identity and internal fraud is also a growing problem for all financial institutions.
- Safety Applications
- Allow operators to see into areas where the environment is hazardous to life or health
- Monitor potential accident areas.
- Monitor residence halls, common areas, or high-risk areas to ensure safety of an educational institution's students and faculty.
- Help reduce the severity of some incidents by the timely dispatch of police, fire, and emergency personnel.
- Monitoring traffic on a highway or bridge.
- Management Tools
- Train employees, check stock on store shelves and monitor retail sales floor coverage, production lines, etc.
- Demonstrate management's due diligence towards protecting employees, clients, and visitors, and perhaps avert or minimize litigation and negative publicity
- Document video images on magnetic tape or optical hard drives to record events. This information may be reviewed and later presented as evidence for prosecution of criminals, or as a training tool.
Color CCTV cameras VS Black and White CCTV cameras?Color cctv cameras generally require higher levels of lighting than their monochromatic (B/W) counterparts. Color produces a more natural, richer image than black and white and may keep the operator's interest for longer periods of time. It also makes it easier to detect subjects. For example, with a color system a viewer can easily distinguish a red car from a green one, while on a black and white system both cars would appear a similar shade of grey. In retail applications, a color system can help security personnel identify shoplifters and their clothing more easily and convincingly. Color accuracy is extremely important in gambling casinos, where hundreds of dollars can ride on the ability to recognize the difference between maroon chips and red ones.
While the use of color cctv cameras is growing, black and white cctv cameras continue to offer some distinct advantages. Black and white cctv cameras are better suited for extremely low light situations. The ability to capture good quality images in low light situations increase the cost of both black and white and color cctv cameras. Before purchasing cctv cameras, you should consider the crossover points between lighting costs and camera costs. It's possible that low-light cctv cameras will cost less than paying to increase the lighting level of a parking lot.
Analog CCTV camera or Digital CCTV camera?In the past, all CCTV Cameras were attached to a Multiplexer (A device which can split multiple camera pictures onto 1 CCTV Monitor). The Multiplexer then sends the camera images to a Time Lapse Video Player (A device which unlike a normal VCR, can prolong video recording for up to 960 hours on a 3 hour tape by missing out frames). This method is still used today for simple CCTV installations but the quality of recording is usually very low (1 Frame Per 12.8 Seconds). Nowadays, most CCTV systems are Digital. Digital Surveillance uses current PC technology to digitize camera images, compress them into a PC friendly format and store them on a PC's Hard Disk Drive. CCTV pictures are stored on a computer Hard Drive which means you can save lots of CCTV footage and access them very easily and quickly. By using a PC to store CCTV footage, you are able to take advantage of today's powerful PC technology and capture CCTV images in High Resolution and Real Time.
How to Choose a CCTV Camera?Choosing the correct CCTV Camera for your surveillance system is very important. The CCTV Camera, together with a CCTV Lens, uses a CCD (Charge Coupled Device) sensor that captures the image and turns it into an electric signal which can be sent to a monitor or surveillance system.
You need to decide the following when choosing a CCTV camera & CCTV lens:
- The environment the camera will be in i.e. Will the camera be situated:
Indoors / Outdoors- The amount of light or variable light conditions for the camera i.e. Will the camera have to record in low-light conditions?
- The Field of View required for the camera. How wide or narrow an angle you require. The distance within which objects in a picture are in focus.
- The Focal Length- How far away objects you wish to record will be from the camera
- Your budget
