A video management system can support many different features:
- Simultaneous viewing
- Recording of video and audio
- Event management functions including intelligent video
- Camera management
- Search options and playback
- User access control and activity (audit) logging
- Public View Monitoring (PVM)
A key function of a video management system is enabling live and recorded video to be viewed in efficient and user-friendly ways. Most video management software applications enable multiple users to view in different modes such as split view (to view different cameras at the same time), full screen or camera sequence (where views from different cameras are displayed automatically, one after the other).
Many video management software programs also offer a multi-camera playback feature, which enables users to view simultaneous recordings from different cameras. This provides users with an ability to obtain a comprehensive picture of an event, which is helpful in an investigation. Additional features may be multi-monitor viewing and mapping, which overlays camera icons that represent the locations of cameras on a map of a building or area.
Axis’ advanced network video products enable multi-streaming, where multiple video streams from a network camera or video encoder can be individually configured with different frame rates, compression formats and resolutions, and sent to different recipients. This capability optimizes the use of network bandwidth.
With video management software such as AXIS Camera Station, video can be recorded manually, continuously and on trigger (by motion or alarm), and continuous and triggered recordings can be scheduled to run at selected times during each day of the week.
Continuous recording normally uses more disk space than an alarm-triggered recording. An alarm-triggered recording may be activated by, for example, video motion detection or external inputs through a camera’s or video encoder’s input port. With scheduled recordings, timetables for both continuous and alarm/motion-triggered recordings can be set.
Once the type of recording method is selected, the quality of the recordings can be determined by selecting the video format (e.g., H.264, MPEG-4, Motion JPEG), resolution, compression level and frame rate. These parameters will affect the amount of bandwidth used, as well as the size of storage space required.
Network video products may have varying frame rate capabilities depending on the resolution. Recording and/or viewing at full frame rate (considered as 30 frames per second in NTSC standard and 25 frames per second in PAL standard) on all cameras at all times is more than what is required for most applications. Frame rates under normal conditions can be set lower — for example, one to four frames per second — to dramatically decrease storage requirements. In the event of an alarm — for instance, if video motion detection or an external sensor is triggered — a separate stream with a higher recording frame rate can be sent.
Recording and storage
Most video management software use the standard Windows file system for storage, so any system drive or network-attached drive can be used for storing video. A video management software program may enable more than one level of storage; for instance, recordings are made on a primary hard drive (the local hard disk) and archiving takes place on either local disks, network-attached drive or remote hard drive. Users may be able to specify how long images should remain on the primary hard drive before they are automatically deleted or moved to the archive drive. Users may also be able to prevent event-triggered video from being deleted automatically by specially marking or locking them in the system.
Event management and intelligent video
Event management is about identifying or creating an event that is triggered by inputs, whether from built-in features in the network video products or from other systems such as point-of-sale terminals or intelligent video software, and configuring the network video surveillance system to automatically respond to the event by, for example, recording video, sending alert notifications and activating different devices such as doors and lights.
Event management and intelligent video functionalities can work together to enable a video surveillance system to more efficiently use network bandwidth and storage space. Live camera monitoring is not required all the time since alert notifications to operators can be sent when an event occurs. All configured responses can be activated automatically, improving response times. Event management helps operators cover more cameras.
Both event management and intelligent video functionalities can be built-in and conducted in a network video product or in a video management software program. It can also be handled by both in the sense that a video management software program can take advantage of an intelligent video functionality that is built into a network video product. In such a case, the intelligent video functionality, such as video motion detection and camera tampering, can be performed by the network video product and flagged to the management software program for further actions to be taken. This process offers a number of benefits:
- It enables a more efficient use of bandwidth and storage space since there is no need for a camera to continuously send video to a video management server for analysis of any potential events. Analysis takes place at the network video product and video streams are sent for recording and/or viewing only when an event occurs.
- It does not require the video management server to have a fast processing capability, thereby providing some cost-savings. Conducting intelligent video algorithms is CPU intensive.
- Scalability can be achieved. If a server were to perform intelligent video algorithms, only a few cameras can be managed at any given time. Having the intelligent functionality “at the edge”, i.e. in the network camera or video encoder, enables a fast response time and a very large number of cameras to be managed proactively.
An event can be scheduled or triggered. Events can be triggered by, for example:
- Input port(s): The input port(s) on a network camera or video encoder can be connected to external devices such as a motion sensor or a door switch.
- Manual trigger: An operator can make use of buttons to manually trigger an event.
- Video motion detection: When a camera detects certain movement in a camera’s motion detection window, an event can be triggered.
- Camera tampering: This feature, which allows a camera to detect when it has been intentionally covered, moved or is no longer in focus, can be used to trigger an event.
- Audio trigger: This enables a camera with built-in audio support to trigger an event if it detects audio below or above a certain threshold.
- Temperature: If the temperature rises or falls outside of the operating range of a camera, an event can be triggered.
Network video products or a video management software program can be configured to respond to events all the time or at certain set times. When an event is triggered, some of the common responses that can be configured include the following:
- Upload images or recording of video streams to specified location(s) and at a certain frame rate. When using the event-triggered functionality in Axis network video products’ web interface, only JPEG images can be uploaded. When using a video management software program, a video stream with a specified compression format (H.264/MPEG-4/Motion JPEG) and compression level can be requested from the network video product.
- Activate output port: The output port(s) on a network camera or video encoder can be connected to external devices such as alarms. (More details are provided below on output ports.)
- Send e-mail notification: This notifies users that an event has occurred. An image can also be attached in the e-mail.
- Send HTTP/TCP notification: This is an alert to a video management system, which can then, for example, initiate recordings.
- Go to a PTZ preset: This feature may be available with PTZ cameras or PTZ domes. It enables the camera to point to a specified position such as a window when an event takes place.
- By means of a 3rd party service, send an SMS (Short Message Service) with text information about the alarm or an MMS (Multimedia Messaging Service) with an image showing the event.
- Activate an audio alert on the video management system.
- Enable on-screen pop-up, showing views from a camera where an event has been activated.
- Show procedures that the operator should follow.
In addition, pre-alarm and post-alarm image buffers can be set, enabling a network video product to send a set length and frame rate of video captured before and after an event is triggered. This can be beneficial in helping to provide a more complete picture of an event.
A unique feature to network cameras and video encoders, in comparison with analog cameras, is their integrated input and output (I/O) ports. These ports enable a network video product to connect to external devices and enable the devices to be manageable over a network. For instance, a network camera or video encoder that is connected to an external alarm sensor via its input port can be instructed to only send video when the sensor triggers.
The range of devices that can be connected to a network video product’s input port is almost infinite. The basic rule is that any device that can toggle between an open and closed circuit can be connected to a network camera or a video encoder. The main function of a network video product’s output port is to trigger external devices, either automatically or by remote control from an operator or a software application.
|Door contact||Simple magnetic switch that detects the opening of doors or windows.||When the circuit is broken (door is opened), images/video as well as notifications can be sent from the camera.|
|Passive infrared detector (PIR)||A sensor that detects motion based on heat emission.||When motion is detected, the PIR breaks the circuit and images/video as well as notifications can be sent from the camera.|
|Glass break detector||An active sensor that measures air pressure in a room and detects sudden pressure drops. (The sensor can be powered by the camera.)||When a drop in air pressure is detected, the detector breaks the circuit, and images/video as well as notifications can be sent from the camera.|
|Door relay||A relay (solenoid) that controls the opening and closing of door locks.||The locking/unlocking of a door can be controlled by a remote operator (over a network) or be an automatic response to an alarm event.|
|Siren||Alarm siren configured to sound when alarm is detected.||The network video product can activate the siren either when motion is detected using the built-in video motion detection or using “information” from the digital input.|
|Alarm/intrusion system||An alarm security system that continuously monitors a normally closed or open alarm circuit.||The network video product can act as an integrated part of the alarm system that serves as a sensor, enhancing the alarm system with event-triggered video transfers.|
Video motion detection
Video motion detection (VMD) is a common feature in video management systems. It is a way of defining activity in a scene by analyzing image data and differences in a series of images. With VMD, motion can be detected in any part of a camera’s view. Users can configure a number of “included” windows (a specific area in a camera’s view where motion is to be detected), and “excluded” windows (areas within an “included” window that should be ignored). Using VMD helps to prioritize recordings, decrease the amount of recorded video and make searching for events easier.
Active tampering alarm
This intelligent video functionality, embedded in many Axis network video products, can be used as an event trigger when a camera is manipulated in any way; for instance, through accidental redirection, blocking, defocusing or being spray-painted, covered or damaged. Without such detection, surveillance cameras can become of limited use.
All video management software applications provide the ability to add and configure basic camera settings, frame rate, resolution and compression format, but some also include more advanced functionalities, such as camera discovery and complete device management. The larger a video surveillance system becomes, the more important it is to be able to efficiently manage networked devices.
Software programs that help simplify the management of network cameras and video encoders in an installation often provide the following functionalities:
- Locating and showing the connection status of video devices on the network.
- Setting IP addresses.
- Configuring single or multiple units.
- Managing firmware upgrades of multiple units.
- Managing user access rights.
- Providing a configuration sheet, which enables users to obtain, in one place, an overview of all camera and recording configurations.
An important part of video management is security. A network video product or video management software should enable the following to be defined or set:
- Authorized users
- Different user-access levels, for example:
- Administrator: access to all functionalities (In the AXIS Camera Station software, for instance, an administrator can select which cameras and functionalities a user may have access to.)
- Operator: access to all functionalities except for certain configuration pages
- Viewer: access only to live video from selected cameras
Public View Monitoring (PVM)
Public View Monitor (PVM) systems provide live video of the retail environment. A monitor displays selected security surveillance video to the public. For example, customers may see live images of themselves as they enter a store sending a strong message that video surveillance is in place. This deters undesirable behavior, helping to reduce losses and improve customer relations.
System setup examples
Network video is a scalable, flexible and cost-effective route to powerful PVM solutions and different system setups are available.
Monitor displaying a video feed from network cameras via a NVR/VMS.
Monitor displaying a video feed from network cameras via a video decoder.
Monitor displaying a video feed from network cameras via a smartphone or tablet.