Networked Video Surveillance
by
Satish K. Gupta
Founder, Executive Vice President, Cradle Technologies
Video Surveillance Industry is experiencing a tremendous growth in demand worldwide, not only due to increased security demands, but also due to globalization. As businesses need to operations dispersed in multiple locations, it has become critical that the video surveillance systems go beyond security and help improve the real time remote supervision. Internet is ubiquitous and the broadband is becoming available and affordable everywhere. It is required that the video and audio from any location such as a factory floor or hotel lobby be accessible by appropriate and authorized management from anywhere regardless of location, anytime and by using any means, such as a laptop or a PDA., and in a very secure way. Whenever, there is a situation that warrants immediate attention an alert with relevant information needs to be sent to appropriate personnel in real time. These requirements are being driven as much by the medium size commercial customers as by the enterprise and infrastructure projects.
Most of the solutions available currently categorized as CCTV, DVRs and NVRs do not often take adequate advantage of the internet and do not address the critical needs of the customers who are constantly on the go and would like to access their video surveillance network in a manner analogous to the their IT network. As a result of these compelling requirements a new category of products called Networked Video Surveillance Systems has emerged on the scene. Cradle Technologies NVSS are engineered from the ground up for the Internet, and lead this category.
As the industry embarks on this next generation of video surveillance solutions, it is also important to consider the rapidly growing need for Video Content Analysis. The need for automatic analysis of the video streams, live or forensically, is motivated by the reality of the explosive growth in video surveillance and cost and ineffectiveness of humans watching video screens. The key market requirement is that interesting events such as, someone crossing a fence, or someone walking or driving the wrong way, or unattended baggage at the airport be detected in real time and appropriate action enabled. Although, VCA solutions are far too expensive, and undependable to be ubiquitous, the technology advances continue to improve the cost and performance. The Networked Video Surveillance Systems must also fully enable a ubiquitous deployment of relevant event detection and response management. In other words video intelligence must be actionable. One of the most significant factors in improving the accuracy and responsiveness is that the analysis be performed right at the camera where video is captured. This approach is often termed �intelligence-at-the-edge�.
In the rest of this paper we will discuss some of the technical and functional implications of this new category of video surveillance solutions we call NVSS. We will also discuss the role of IP cameras and their limitations in networked environment, and a vision of video content analysis as a tool to implement video event based data base management systems.
A Networked Video surveillance system must provide the following capabilities:
1. Secure Access
2. Satisfactory remote viewing experience of live audio video streams in spite of Internet bandwidth variations
3. Location independent access to all features and functions remotely or locally
4. Support for mobile devices
5. Local storage and Network Attached Storage (NAS)
6. Local and remote archiving
7. Dynamic DNS to allow use of dynamic IP addresses
8. Variety of user classes to allow management of access authority
9. Real time alerts
10. Integration with other IT and Security applications
11. 24x7 availability as surveillance moves into a mission critical role
Secure Access:
Surveillance Audio and Video from business locations such as factories, franchises or warehouses need to be transported over the network for remote supervision. These video streams should not be viewable by any one not authorized to do so. The streams must be encrypted and utilize virtual private networks to ensure secure completely secure access.
Remote Viewing:
For the purposes of remote supervision, authorized individuals need to view the video over the internet from any location worldwide. At any given moment the actual available bandwidth is unpredictable and can change at any moment. NVSS, estimates the available bandwidth and adapts the compression parameters to facilitate smooth motion video viewing experience. In addition to adjusting compression rates to the instantaneous bandwidth of the internet, audio and video needs be kept in synch for a richer viewing experience.
Location Independence:
Authorized personnel need to be able configure, change settings, view live video, analyze stored video among all the features and functions from anywhere on the Internet. This requires that a full functional portable client be supported both locally, on LAN or on the internet.
Mobile Device Support:
Mobile phones and PDAs are ubiquitous and are more easily accessible that the computers. NVSS must send alerts as SMS or email messages to portable devices so as to enable prompt action if needed
Network attached storage:
Most current solutions require that the video be stored locally to the DVR or NVR. There have been many cases where the system has been stolen along with the local storage. There is also a requirement for adding storage beyond the capacity provided locally. Network attached storage enables the NVSS to extend storage capabilities of the system allows it be located away from the system and provide RAID capabilities for added availability.
Archiving:
Mission Critical Video data needs to be archived on demand or automatically locally or away from the surveillance system, for later use or for audit purposes. NVSS must enable users to archive either locally or remotely and also allow for automatic continuous archival.
Dynamic DNS:
Most current systems require that the IP address of the DVR or the NVR be fixed. This adds additional cost and may make the cost prohibitive when the video surveillance network is made of many nodes. NVSS must support dynamic DNS capabilities so dynamic IP address can be used for each NVSS node.
User Classes:
Businesses require that control and management of the surveillance systems be performed only by the authorized individuals. Certain cameras should be restricted to specific personnel. NVSS must implement comprehensive user classes and authorization mechanisms to facilitate such control.
Alerts:
NVSS are required to generate timely alerts based on detected video events or combination of related events from related applications from one or more locations. These alerts are to be transmitted as e-mail or SMS messages to appropriate personnel or invoke other actions as desired, such as sounding an alarm or close a gate.
Integration:
Often there are other solutions such as fire safety, or access controlled is also deployed in the same facility as NVSS. All these systems need to operate in harmony and over multiple locations. Appropriate open programming interfaces must be made available by the NVSS to facilitate this integration to suit each situation.
Availability:
Since the video surveillance is moving into a mission critical role and access may be required from locations spread out all over the world, it is necessary that the NVSS be available 24x7. Redundant systems can be deployed at the same location. In addition, NVSS must support intelligent UPS which communicates with the NVSS and can facilitate appropriate action, such as graceful shutdown or sending necessary alerts, in case of unexpected power outages.
Video surveillance networks
Video Surveillance networks can be classified as either loosely integrated or tightly integrated networks.
Loosely Integrated Video Surveillance Networks
Certain businesses are organized as collection of one or more physically separated locations. For example, a bank may have branches spread all over a city and also have zonal offices or head quarters. Video data from one branch has rather weak relationship to the video data from another branch. An event, such as customer teller disagreement on a transaction, happening in one branch needs to be typically attended by the local management or zonal management and there is little to no involvement from another branch in real-time. In such situations video surveillance systems from each branch may be viewed and controlled by zonal office or head quarters but there is very little need to have a simultaneous integrated view of all cameras in real-time from one terminal. There are many such situations in businesses that have multiple franchises, or owners that have a multiple location such as administrative offices and factories. Each location may need a modest number of cameras typically less that 100. The operating or security management typically handles one location at a time. At each location one or more local networked video surveillance system is installed with the local video data stored locally or if needed archived remotely. Each location can be viewed by appropriate personnel locally or remotely according. For forensic analysis purposes, data from allocations is available to the central management authorities. Events that require viewing and correlating video from multiple locations can then be analyzed by at a central facility. These networks are appropriately called �Loosely integrated video surveillance networks.� Cradle�s NVSS products, along with its Cradlewatch video management software are ideally designed for these kinds of networks. In addition to addressing all the requirements mentioned earlier, authorization together with controlled local and remote access at individual camera level provides comprehensive ability to mange this class of networks.
Tightly Integrated Video Surveillance Network
There are situations such as large airports or city or state wide law enforcement where a number of cameras from a very large set of cameras, some times within a large campus like the airport, or multiple locations in a city, need to accessed simultaneously and critical emergency situations needs to managed from a command center. These are typically large public or private infrastructure projects. In such cases it is necessary that closely integrated view in a command and control center is presented in real time. It is also often necessary that the video surveillance is coordinated with other systems such as dispatching of fire security and law enforcement personnel. A developing crisis needs to be tracked and resolved in real time. These projects call for a very tightly integrated view of the entire video surveillance system and such networks are called tightly integrated video surveillance networks. TruSentry offers systems with comprehensive command and control and situation management capabilities which along with Cradle�s NVSS and IP based cameras complete a comprehensive �tightly coupled video surveillance network.�
These two classes are primarily for the purposes of conceptualizing solutions needed in a particular situation. Typically, one would see elements of both loosely coupled as well as tightly coupled networks in a complex infrastructure project.
From DVRs and NVRs to NVSS
At the heart of most Video surveillance systems is audio video recording device called a Digital Video Recorder or a Networked Video Recorder and sometimes what is called a Hybrid DVR?
In case of a DVR analog Cameras are connected directly to the DVR. A video capture digitizer and compression subsystem is co located with the recording system and Audio and Video is recorded on hard disk drives. Videos can be either viewed live or from the recoded content. Live viewing of video and audio is enabled by compressing and streaming analog content available at the DVR. This makes for simultaneous viewing of multiple cameras on a single screen easy and inexpensive.
NVRs connect to IP cameras over a LAN or a WAN and record a data stream which has been digitized and compressed either inside the camera called IP camera, or in a streamer which takes in multiple analog cameras and streams video as an IP stream to the NVR. For the purposes of live viewing the compressed streams received at the NVR need to be uncompressed and re-assembled as per viewer request. NVRs are primarily servers that run on standard x86 compatible servers. Milestone, OnSSI, Genetec are some of the key suppliers of NVR software.
Hybrid DVRs or NVRs try to take the best of both and support DVR functions as well as IP cameras and streamers to provide a complete video surveillance solution. Some of the leading products in the Hybrid Category are Verint, TruSentry and Pilot.
DVRs, NVRs and Hybrid DVRs, all have their roots in the traditional video surveillance view of systems primarily focused on Security. IP cameras and NVRs have taken advantage of the more modern connectivity and wiring techniques developed for LANs and WANs using the Ethernet protocol, wiring, switches and IP protocol for data transport. By and large Networking has been an after thought in these solutions. All these solutions fail to deliver the requirements listed above.
NVSS is the natural next step for video surveillance. However, at the heart of an NVSS is the Internet. Internet is far more than wiring and IP protocol. The systems need to be engineered from the ground up considering the strengths and challenges of the internet.
IP protocol has certain limitations in streaming. Several techniques are available to facilitate audio and video streaming.
Internet bandwidth available for a session can vary from moment to moment. Adaptive compression schemes need to be implemented which can estimate instantaneous available bandwidth and modify compression parameters in real time to facilitate a decent viewing experience
Security is a well known issue on the internet. Video and Audio needs to be encrypted. Virtual private network sessions need to be used to ensure adequate security
Unauthorized access is more serious concern if the access is to be made available from any browser anywhere. Proper authorization controls must be implemented
Video data needs to be stored away from the location of capture for archiving and protection from unintended loss by events such as: theft or fire.
NVSS represent a new category of Video Surveillance solutions. Along with the challenges the Internet offers opportunities for broadening the application of surveillance to include management of business operations. It also is the next step towards convergence of video surveillance data and infrastructure with the IT infrastructure. We can also expect that with relevant event detection, video data can be managed as data base much like the current Information data bases. NVSS is now moving video surveillance, from the role security to a mission critical business operations role. Cradle Technologies leads the way in this category, and has introduces its NVSS product line which is the first one to be engineered from the ground up for the internet and is poised to take full advantage of the opportunities offered by the internet for surveillance.
Analog and IP Cameras
Analog cameras take advantage of TV broadcast standards and connectivity infrastructure and provide analog output that is connected to video surveillance equipment via coaxial cable. As a result analog cameras remain very inexpensive and a very large variety of cameras are available in the consumer industry that can be used by the surveillance industry. There is also a very large installed base of analog cameras which are of good quality and the customers would prefer to continue to use them as they move on the latest generation of surveillance solutions. For analog cameras digitization and compression are handled by the surveillance equipment.
Analog cameras have a weakness which may turnout out be fatal for their future. This is the limitation of the current TV standard in terms of pixel resolution. Analog cameras are limited to standard TV resolution. In consumer electronics high resolution mega-pixel cameras are already inexpensive and ubiquitous. HDTV is rapidly growing. For video content analysis higher resolution is required to increase accuracies. As the cost of storage continues to decrease it is inevitable that the surveillance industry will demand higher resolution cameras. Analog cameras have no way to keep up with this trend. There currently is no standard for high resolution cameras. High resolution cameras would most likely use the IP protocol in a very limited way to transport raw pixel data to other equipment attached in point-to- point configuration. We should call them Digital Cameras to differentiate them from today�s IP cameras.
Recently, as the cost of digitization and compression technologies have reduced, a category of cameras called IP cameras have come on the scene and are rapidly gaining acceptance. These IP cameras today digitize and compress video within the camera and stream the compressed video streams over the LAN wiring or the internet using IP protocol. Some of these cameras also includes wire less capabilities and uses the WiFi network to connect to the video server. IP cameras can also be viewed directly from anywhere over the Internet. Clearly some of the features that simplify connectivity where LAN wiring already exists, wireless access where it is needed make IP cameras a great choice. They are part of an unstoppable trend. However, in order to take full advantage of the Internet as mentioned earlier, IP cameras will co-exist with intelligent and powerful streamers which accept a small number of analog or IP cameras as input and connect to a network of video surveillance systems, take full advantage of the network features and deliver the video content analysis capabilities, or �intelligence-at-the-edge� of the network.
From a perspective of the Video Surveillance network, today�s IP camera�s have following limitations:
1. Lack of encryption
2. Lack of VPN capabilities
3. Lack of direct authorization control
4. Lack of bandwidth adaptation capabilities
In addition, from the point of view of delivering video content analysis, there is a need to analyze raw uncompressed pictures and detect events. This is necessary to improve accuracy and responsiveness. Some IP cameras companies are beginning to offer VCA integrated within the camera. However, VCA is in its early stages, there are rapid innovation and no standardization. It is most likely that an extensible open platform is needed close to camera for most effective deployment of real time relevant event detection using the latest and rapidly evolving video content analysis techniques. Axis Communications is one of leaders in the IP camera segment, although almost all surveillance camera providers are offering IP camera. Some of them are also providing VCA close to or integrated with the camera. I/O image is a compny which perhaps has the leading product line in this segment.
When above limitations are not issues, IP cameras as we know them will probably thrive? However, in order to take full advantage of the opportunities offered by the Internet, IP cameras will most likely co-exist with what could be termed a �Two piece IP camera� solution. The Two piece IP camera solution is made of one to four analog or digital cameras, attached to an NVSS-streamer. This streamer is fully functional NVSS edge device and is capable of delivering all the necessary features listed above. In addition, this streamer is capable of Video Content Analysis that can be added on demand. The combination of a VCA capable NVSS with a digital or analog camera will overcome the limitations faced by traditional IP cameras.
Streamers & 2 piece IP cameras
Integration with other security and operational applications
One of the critical requirements of NVSS is to work well with other related solutions as seamlessly as possible. Most businesses have access control solutions that track entry and exits to secured areas. It is a natural requirement that the surveillance audio and video be effectively accessible and synchronized with the events associated with these systems. There are systems for building management that include fire and hazardous material safety. These systems need to be appropriately integrated with he NVSS. In addition, many establishments have point of transaction systems, it is required that the audio and video of a transaction be available when needed. This video would enable verification of a disputed transaction or coaching opportunity for improving customer service. Such integration with a large variety of applications is best performed by professionals with domain expertise in each vertical. It is required that an open Application Programming Interface (API) be made accessible for domain experts to effect such integration to address the needs of corresponding vertical markets. Cradle�s NVSS, offers such an API with necessary support for such integration.
Video Content Analysis and Event Driven Surveillance
It is not very hard to see that the explosive demand for video surveillance creating a deluge of video to be viewed live and stored for later forensic analysis. It is becoming unaffordable to employ enough people to watch for interesting events. Furthermore, most people watching video are not able to focus with sufficient attention and miss many critical events. The challenge is undiminished, when forensic analysis is needed on stored video. It is very time consuming to view the video to tease out the relevant events for timely action. This was quite apparent in the July 5, 2005 explosions in the London Subways. Fortunately, London is a city equipped with one of the most comprehensive video surveillance networks in the world. Investigation professionals managed to extract the connected events, although it took several weeks of rather tedious effort. What is needed is an efficient event driven architecture for managing real time and stored video. Enter, Video Content Analysis (VCA) to the rescue.
Video Content Analysis
VCA as a technology has been around for over 10 years and is being deployed in many situations. For example, one can monitor a border fence with video surveillance cameras and automatically detect the situation where some one tries to cross the fence with in the view of the camera. This can be done in real time and appropriate alerts can be sent for immediate action. There are other events such as; some one walking the wrong way or entering an exit door, or an object left unattended that needs to be detected. Solutions for these situations based on the current VCA technology tend to be expensive, tedious to deploy and leave much to be desired in terms of accuracy. However, these solutions are improving, and are continuing to gain acceptance in high value situations. ObjectVideo and ActivEye are two of the leading OEM technology providers in this segment.
The market requires that detection of relevant events be available for a broad set of video surveillance solutions. Businesses need the surveillance process to be driven by interesting events. VCA needs to be deployable ubiquitously and scheduled on demand. For NVSS, it means that any of the cameras could be directed to �look� for a particular event and send a real time alert if so desired or tag the video in way that it can be retrieved efficiently. Potentially interesting events in surveillance video can be classified in 3 categories: People Video Analytics, Vehicle Video Analytics, and Object Video analytics. Some examples of these are:
People Video Analytics
Counting people
Intrusion
Cashier absent from station
Wrong way movement
Face capture when in view
Falling
Running
Vehicle Video Analytics
License plate reading
Stopped car
Wrong way
Speeding
Model and make
Object Video Analytics
Unattended object
Removed object
Object moved
Many of these kinds of events are of interest beyond security. It is required that these relevant events are detected and the video be appropriately tagged with to facilitate efficient forensic analysis.
Intelligence-at-the-edge
Most video surveillance solutions today store all the video captured for later forensic review. Introduction of NVSS would require all of this video to be transported over the internet for storage or archiving especially if it is to be used for mission critical operations. What is needed is the detection of relevant events right at the camera and transport only the video associated with the relevant events. This could decrease the quantity of video to be transported by a factor 10. This would lead to much more manageable demands on the required internet bandwidth and storage. A natural consequence, of this need is to place the VCA, near the camera, or �intelligence-at-the-edge�. This trend of moving the intelligence to the edge of the network is inevitable. It enables the opportunity to perform the VCA at the highest quality and resolution of the picture possible and also improve the response time detected by alerts to be generated directly from the camera location instead of from some central server.
Looking forward a bit, one can easily visualize the video to be organized as Video Data Base with a comprehensive Video Data Base Management System to support its effective use in business.
Markets
Video Surveillance market is segmented in three segments. Networked Video Surveillance Systems are the next generation of solutions that would dominate all three segments.
Consumer Segment has so far been served by the WebCams. They are rapidly moving on to IP cameras as they are becoming more affordable. IP cameras for consumer applications use the internet in rather simple manner. Going forward, two piece IP cameras solutions which address the issues of encryption, VPN, authorization and bandwidth adaptation as well as relevant detection near the camera (VCA) are likely to become affordable enough to penetrate this market.
Mid Size- and Commercial and segment is most rapidly realizing the value of remote supervision. These businesses often have multiple locations and owners or senior management is often on the move. NVSS enable them to be view and direct operations from anywhere, anytime. This segment leads the way in deploying networked video surveillance to go beyond security and improve management of operations.
Public and private infrastructure segment is driven to use fully networked solution by the requirement of managing complex situations. For example, a potential terrorist incident would require the video scene to be accessible by the various law enforcement agencies concurrently and coordination to be performed from a command and control center. There are solutions already being offered in this segment. The NVSS solutions will begin addressing the requirements mentioned earlier.
Conclusion
All the technical pieces are in place and market demand is there for comprehensive NVSS based solutions to be made available at affordable prices to the market place. Cradle intends to take advantage of these developments and views these developments as key to enable video surveillance to take its rightful place in the operational management fully integrated with the IT systems.
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