Digital Video Design Guide

Digital VideoDesign Guide

Symmetry™

9600-0435

© Group 4 Technology 2006

All rights reserved. No part of this publication may be reproduced in any form without the written permission ofGroup 4 Technology.

Group 4 Technology cannot be held liable for technical and editorial omissions or errors made herein; nor forincidental or consequential damages resulting from the furnishing, performance or use of this material.

NOTE: This equipment has been tested and found to comply with the limits for a Class A digital device,pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection againstharmful interference when the equipment is operated in a commercial environment. This equipmentgenerates, uses and can radiate radio frequency energy and, if not installed and used in accordance withthe instruction manual, may cause harmful interference to radio communications.

Operation of this equipment in a residential area is likely to cause harmful interference. In which case, theuser will be required to correct the interference at his own expense.

Digital Video Design Guide9600-0435

Issue 1.1 – 24th July 2006ENVS and Symmetry are trademarks of Group 4 Technology Ltd.All trademarks acknowledged.

Image compression software is based in part on the work of the Independent JPEG Group.

MPEG-4 Video components powered by ATEME

™

Digital Video Design Guide 1

Contents1 Preface ...................................................................................................................... 32 Chapter 1: Introduction to Digital Video ................................................................ 4

Introduction ....................................................................................................................................... 4About the Symmetry Software ...................................................................................................... 5Benefits of Digital Video................................................................................................................ 6About MPEG-4 Compression ....................................................................................................... 6

Features and Benefits – ENVS......................................................................................................... 7ENVS – Key Features................................................................................................................... 7

About the Network (IP) Camera Interface ....................................................................................... 9Key Features ................................................................................................................................ 9

About the DVR Interface................................................................................................................. 10Feature Comparison Matrix............................................................................................................ 11Features and Benefits – Symmetry Software ............................................................................... 12

Symmetry – Key Features .......................................................................................................... 14Features and Benefits – Video Storage Management Module ................................................... 15

Video Storage Management Module – Key Features................................................................. 15

3 Chapter 2: Computer Requirements..................................................................... 16Requirements for the Symmetry Software ................................................................................... 16

Supported Operating Systems.................................................................................................... 16Database Server or Standalone Machine Requirements ........................................................... 16Client Requirements ................................................................................................................... 17Graphics Card............................................................................................................................. 17Network Capacity........................................................................................................................ 17

Requirements for Video Storage Servers ..................................................................................... 18Number of Video Storage Servers Required .............................................................................. 18Windows Operating System ....................................................................................................... 18Processor and RAM Requirements ............................................................................................ 18Server Disk Space...................................................................................................................... 18Network Attached Storage.......................................................................................................... 18

3 Chapter 3: Designing the System ......................................................................... 19Overview of the IP Camera Configuration Screen ....................................................................... 19Overview of the DVR Setup Screens............................................................................................. 20Overview of Screens used for ENVS Configuration .................................................................... 21

Using the Video Server Screen .................................................................................................. 21Using the ENVS Camera Screen ............................................................................................... 23

Choosing the Camera Resolution ................................................................................................. 24Background to Resolution Standards ......................................................................................... 25

Choosing the Camera Frame Rate ................................................................................................ 26Checking ENVS Frame Rate/Resolution Capacity ....................................................................... 27Selecting the Recording Policies .................................................................................................. 28ENVS Disk Space ............................................................................................................................ 29

ENVS Disk Purging and Warnings ............................................................................................. 30Managing the Network.................................................................................................................... 31

Estimating ENVS Camera Network Usage................................................................................. 31Estimating IP or DVR Camera Network Usage .......................................................................... 32Reducing Network Usage........................................................................................................... 32Changing the ENVS I-Frame Interval ......................................................................................... 34

Contents

2 Digital Video Design Guide

Viewing the Actual Frame and Bit Rates for an ENVS Camera ...................................................35Specifying ENVS Inputs and Outputs ............................................................................................36Specifying the ENVS Overlay Information.....................................................................................37Synchronizing the ENVS Date and Time .......................................................................................38Setting Up Motion Detection...........................................................................................................39Specifying the PTZ Controls and Presets for an ENVS Camera .................................................40

4 Chapter 4: Video Storage.......................................................................................41Choosing ENVS Video Forwarding Schedules .............................................................................41Estimating Required Network Disk Space.....................................................................................43Assigning Each ENVS and IP Camera to a Storage Server .........................................................45Storage Folders................................................................................................................................46

5 System Design Worksheet.....................................................................................476 Index ........................................................................................................................... i


1 PrefaceThis document is written for anyone who is responsible for marketing or specifying systems that use theSymmetry™ digital video software. It explains the components of Symmetry digital video systems, thebenefits, features, and the factors that need to be considered during the design of such a system.

It is essential to follow the guidance given in this book to achieve a satisfactory system design and to obtainthe full potential from the system. An inadequate design may lead to poor performance, or in the worstcases, a system that does not function correctly. Viewing video can place significant additionalrequirements on the PC and network, and careful consideration needs to be given to system design.Factors such as PC requirements, camera resolution, frame rate, disk space and network usage need tobe considered properly prior to installation.

Symmetry uses a network for the transfer of video data, such as for viewing live video. Before starting anysystem design, it is important to gain detailed knowledge about the network. In particular, details of thenetwork speed, spare capacity, type of data that is currently transferred, periods of greatest use andwhether network response is critical to business operation must be known. Symmetry has been designedto minimize network usage, but it is still essential to consider the impact of the system on the network. Thisguide explains how to estimate the impact, and methods to reduce or limit network usage.

The guide contains four chapters:

• Chapter 1 provides an introduction to digital video systems. Sales personnel who require an overviewof the technology and the key selling benefits should refer to this chapter. It has been written in a"random-access" style, enabling the information to be read in any sequence.

• Chapter 2 provides the Symmetry minimum PC requirements. Viewing video can place significantdemands on the PC hardware, and it is therefore important to consider the requirements carefully. Itis recommended that the PC specifications exceed the minimum requirements whenever possible,since this may enhance overall system performance and allow the PCs to be used with futuresoftware developments.

• Chapter 3 describes the factors that need to be considered during system design. It starts with anoverview of the configuration screens, then covers each of the main design topics. This chaptershould be read in sequence.

• Chapter 4 explains the factors that need to be considered when using the Video StorageManagement module to store video recordings on a network device.

Note: This guide is not an installation manual; this information is provided in other manuals. Details ofinstalling an Edge Network Video Server (ENVS) are given in the ENVS Installation Instructions. For detailsof installing Digital Video Recorders or IP cameras, please refer to the appropriate manufacturer'sinformation.


2 Chapter 1: Introduction to Digital Video

IntroductionVideo surveillance and monitoring are increasingly moving to digital solutions. The advantages of digitaltechnology and the wide range of systems available make a digital solution an attractive choice for anyorganization needing to upgrade or implement a new CCTV system.

Early CCTV systems were entirely analog, using cameras with a co-axial output, separate CCTV monitors,a traditional Video Cassette Recorder (VCR) for recording, and possibly a CCTV switcher to switch thevideo pictures to selected monitors. In these systems, control and surveillance software running on a PC isnot used. Many legacy systems in use today are based on a similar architecture, but in most cases theVCR has been replaced by a Digital Video Recorder (DVR), which stores the recorded video in a digitalformat on a hard disk inside the unit (Figure 2-1).

Digital Video Recorder (DVR)

MonitorAnalog cameras

Figure 2-1: DVR Video Surveillance System

Entirely digital solutions use cameras connected directly to the network (Figure 2-2). These are known asnetwork, or Internet Protocol (IP), cameras. The cameras are managed, controlled and viewed from PCs,and all recordings are stored digitally on network storage devices. IP cameras do not normally have afacility for local storage of recordings.

WAN/LANNetwork

Network (IP) cameras

PC with Video Management Software

Figure 2-2: Digital-Only Video Surveillance System using Network (IP) Cameras

Symmetry has an open approach to video hardware (Figure 2-3), which supports IP cameras, a wide rangeof DVRs and the latest development in digital video technology – the Edge Network Video Server (ENVS).The ENVS is a network device for viewing and recording live video from up to four connected cameras.

Introduction to Digital Video


Since it is a network device, any PC on the network running the Symmetry software can view live videofrom the cameras. A key benefit of the ENVS is its "store-and-forward" function, which enables recordedvideo to be stored locally, then forwarded to a network storage location during out-of-hours times.

The ENVS compresses video from standard analog cameras into MPEG-4 digital format, which is thelatest standard in digital video compression technologies designed to minimize network usage and storagerequirements.

WAN/LANNetwork

Network (IP) cameras

Edge Network Video Server (ENVS)

Digital Video Recorder (DVR)

Network Attached Storage (NAS) for Video Storage

Management Module

Client/server PCs running:The "Symmetry Video Essentials" or "Symmetry Video Management" software.The "V

�

� ideo Storage Management" Software.

Figure 2-3: Symmetry Combined Digital and Hybrid Analog/Digital Video System

About the Symmetry Software

Symmetry is software that allows digital video to be viewed, recorded and replayed. Symmetry is availableas a video-only product, or as an integrated component of a comprehensive Security Management System,which can also include access control, intrusion, building control and other components.

Symmetry can be used on a standalone PC, or on a client/server networked system. When used as avideo-only product, up to nine clients can be used, and the server runs the freely-available Microsoft MSDEdatabase engine. With its maximum database size of 2GB, MSDE has been designed and optimized foruse on smaller computer systems.

When used as part of an integrated security management system, between three and an unrestrictednumber of clients can be used, depending on the system purchased. In this case, the server supportsMSDE or the full Microsoft SQL Server 2000/2005 database engine, which meets the needs of largersystems.

There are two versions of Symmetry: "Symmetry Video Essentials" and "Symmetry Video Management".Symmetry Video Essentials enables up to 4 live images to be simultaneously viewed, and supports IP,DVR and ENVS cameras. Symmetry Video Management provides extended software features, such as the



ability to display up to 36 live video images at a single PC, camera sequencing, additional commands andthe display of web pages. The user interface for both packages is similar and has been designed forsimplicity and ease of use. An full comparison of features is provided on page 14.

The "Video Storage Management Module" (page 15) enables recordings from ENVS or IP cameras to bestored in any network storage location, such as on a PC or Network Attached Storage (NAS) device. Thissoftware facilitates the "store-and-forward" function of the ENVS.

Benefits of Digital Video

The benefits of a digital video system include the following:

• Enables live video to be viewed, recorded and replayed from a PC anywhere on the network• Allows long-term digital storage of recordings• Feature-rich PC software brings significant management and control benefits• Enables easy integration with other security or digital analysis software• Reduces system cost in many cases• Eliminates the need to handle tapes or disks• No need for separate analog CCTV monitors; video can be displayed at PCs• Recordings can be saved and distributed electronically• Greater choice – new products are mostly digital• Allows digital signing – gives confidence that a recording has not been tampered with

About MPEG-4 Compression

The ENVS and IP cameras use MPEG-4 compression before storing or transmitting the video data acrossthe network. MPEG-4 is the most suitable compression technique for video that is to be transmitted over IPnetworks, and offers the best compromise between file size and picture quality.

MPEG-4 video frames consist of I-Frames, followed by a series of P-Frames. An I-Frame is a completepicture at a point in time. Each P-Frame specifies only the changes in the video picture from the previousframe. MPEG-4 therefore tracks movement, which results in very efficient compression, but the level ofcompression varies depending on the amount of motion in the camera view. This can make LAN and harddisk usage difficult to estimate, but the advantages of MPEG-4 far outweigh any complexities ofdeployment.

This Design Guide provides advice on how to estimate and minimize LAN and hard disk usage.



Features and Benefits – ENVS

ENVS Key Benefits

• Highest resolution available – supports D1(720x480) resolution

• Store and Forward – Video can be storedlocally, then forwarded to a network location

• Event-based recording minimizes unwantedrecording

• Ability to integrate with access control andintrusion systems

• Enables connection of standard analogcameras for easy upgrade from analog todigital system

• Easy installation• MPEG-4 compression• Reliable and feature rich

The ENVS is a device for recording and streamingvideo from up to four connected cameras. Anoptional 80GB hard disk enables recordings to bestored locally to minimize network traffic.

The ENVS is designed for use with the "SymmetryVideo Management" or "Symmetry VideoEssentials" software, which enable the pictures tobe controlled, viewed, recorded and replayed fromany PC on the network.

When used with the "Video Storage ManagementModule", a store-and-forward function allows anystored recordings to be forwarded to a networkstorage location during out-of-hours times.

The ENVS accepts standard analog cameras.The signal is digitized and compressed into anMPEG-4 digital format before recording andtransmission.

ENVS – Key Features

A summary of key features of the ENVS is given below. Refer to the Feature Comparison Matrix on page11 for a comparison of ENVS units, IP cameras and DVRs.

• Four composite video inputs (models with a single channel also available)• Optional 80GB hard drive for video recordings• Compatible with PAL and NTSC cameras• Maximum D1 resolution (720x480 NTSC, or 720x576 PAL)• Maximum 30 frames per second (NTSC), or 25 frames per second (PAL)• Simultaneous viewing and recording for all four cameras at D1 resolution and 7 frames per second

(NTSC) or 6 frames per second (PAL)• User-configurable MPEG-4 compression• Built-in 10\100Mbit Ethernet port (optionally supplied with a 4-port unmanaged switch for local

network integration)• Four monitor point inputs for connection to devices such as movement detectors



• Two auxiliary relay outputs to switch devices such as wipers on or off• Bi-directional audio channel per camera (enabled by future Symmetry software development)• Pan-Tilt-Zoom (PTZ) controller port, using RS232/422/485 connection• Motion detection zones can be defined for automatic motion detection• Serial port for integration with other systems, e.g. to switch on recording at predefined times of the

day or in response to an alarm condition• Compact flash port (for future use)• Maximum power consumption 1.1A @ 12Vdc• Network transmission is Unicast

Figure 2-4: ENVS Overlay



About the Network (IP) Camera Interface

Figure 2-5: Axis IP Camera

Key Benefits of Interface

• Provides greater flexibility by allowing use ofnetwork (IP) cameras

• Common platform – Avoids the need to use aseparate user interface to view live or recordedvideo from IP cameras

• IP cameras can be included with other cameratypes in camera sequencing, commands andother operations

• The Video Storage Management Module canrecord and manage video from IP cameras

The Symmetry software includes an interfacefor Axis MPEG-4 network (IP) cameras, suchas the 211 or 211A. This interface is provided"as standard" and enables live or recordedvideo from IP cameras to be displayed in thesame screens as those used for ENVS or DVRcameras.

The interface also enables the Video StorageManagement Module to record, store andmanage video from IP cameras.

Key Features

A summary of key features of Axis IP cameras when used with the Digital Video Management software isgiven below. Refer to the Feature Comparison Matrix on page 11 for a comparison of ENVS units, IPcameras and DVRs.

• Built-in 10\100Mbit Ethernet port for connection directly to network• Live Video can be displayed in the Symmetry Virtual Matrix screen• Maximum of 30 frames per second (Axis 211 and 211A)• Maximum 640x480 resolution (Axis 211 and 211A)• MPEG-4 compression• Web browser configuration tool• Pan/tilt/zoom, camera motion alarms and input/output functions supported• Axis cameras tested: 207W, 210, 210A, 211, 211A, 213, 214, 221, 225FD, 232D. Other cameras

may function correctly. The following are not currently supported for use with Symmetry: 207,216FD.

Please refer to the Axis Web site for further information.

A license is required in the Symmetry software for each IP camera used.

Note: Axis IP cameras can be set to MPEG-4 or M-JPEG mode. It is recommended that MPEG-4 mode isused, since recording of pictures from IP cameras is supported only when MPEG-4 mode is selected, andMPEG-4 requires much less network bandwidth at higher frame rates.



About the DVR Interface

Figure 2-6: Proxima DVR

Key Benefits of Interface

• Common platform – Avoids the need to use aseparate user interface to view live or recordedvideo from DVR cameras

• DVR cameras can be included with other cameratypes in camera sequencing, commands andother operations

• Many makes and models of DVR supported• Gives support for legacy systems• Local storage of recordings

A DVR is a device that digitally records video from connected analog cameras. Recording is normally setup to be continuous, and all recordings are stored locally on the DVR's hard disk. Symmetry interfaces witha wide range of DVRs, as shown in Table 1.

Table 1: DVRs Supported

Make/Model DVR SoftwareVersion Tested1

DVR SDK VersionSupported

Verint (Previously Loronix) 4.3 4.5Integral: DVX, Digital Sentry 4.1.2.43 SR2 3.5Dedicated Micros, Digital Sprite 2 1.2 1.2.15.1NICE (All models supporting theversion 8 SDK)

8 8

Spectiva / DVN 5000 2.02b 2.2Cieffe/JCI Proxima / DVN 3000 4.0.1 2.2

Bosch, DIVAR 2 2.10Pelco, DX8000 1.1.00.1121 1.1Hitron, ADR1600 Pro 1.3.5 2.5.4

1The features in the SDK can be dependent on the version of software installed on the DVR.

Note: The above information was correct at the time of publishing this guide. If necessary, please refer toyour local support representative for the latest information.

Live video from any DVR camera can be displayed in the Symmetry Virtual Matrix screen in the same wayas for any other digital video camera. Video archiving should be carried out using software supplied withthe DVR.

The availability of certain functions is dependent on the make or model of DVR being used. Please refer tothe Feature Comparison Matrix on page 11 for further details.



Feature Comparison MatrixTable 2: Feature Differences Between Different Types of DVR, IP Camera and the ENVS

DVRs IP

Verin

t Wav

elet

Inte

gral

DVX

Dig

ital

Sent

ryD

edic

ated

Mic

ros

Dig

ital S

prite

2 fa

mily

NIC

E

Cie

ffe S

pect

iva/

Prox

ima

JCI D

VN

500

0/30

00

Bos

ch D

ivar

2

Pelc

o D

X800

0

Hitr

on A

DR

1600

PR

O

AXI

S –

MJP

EG

AXI

S –

MPE

G4

ENVS

View live video in Virtual Matrix � � � � � � � � � � �

Sequence live video � � � � � � � � � �

Click map icon to view live video � � � � � � � � � � �

PTZ camera control � � � � � � � �

Snap camera to preset position � � � � � � � �

MPEG-4 compression � � �

Change video settings such as frame rate andquality using commands from Symmetry �

Receive and display device alarms such asvideo loss and motion detection � � � � � � � � �

Local control from serial interface �

Max. simultaneous client connections per unit U U 5 U 41 4 4 U U U 15

View

ing/

Con

trol

Max. live camera connections per unit U U U U U 8 U U 1 1 4Start/stop recording from Symmetry software � �

Automatic "tagging" on alarm/event, withprogrammable pre/post-alarm record times2 � � � � � � � � � �

Tag video on intercom or DMP events � � � � � � � � � �

Local storage of recordings � � � � � � � � �

Store-and-forward function �

Rec

ordi

ng

Pre-alarm buffer (avoids continuous recording) �3

�

Video playback from Symmetry clients � � � � � � � � � �

Pause, print and skip/change playback speed � � � �4

� � � �5

� �

Play back recording associated with an alarmfrom Alarms or Reports screens � � � � � � � � � �

Play

back

Bookmark and export video (for MP4 codec) � � � � � � � � � �

1 Proxima (DVN 3000) only; unspecified for Spectiva (DVN 5000).2 Pre-event recording requires continuous recording for DVR and IP cameras.3 Used only for recordings triggered by DVR itself.4 Skip forward/back not supported.5 Pause not supported.

U = Unspecified



Features and Benefits – Symmetry Software

Figure 2-7: Video Playback

Key Selling Benefits

• Supports installations using a wide range of videotechnologies

• Feature-rich; gives all the tools needed to control andmanage video

• Easily integrated with access and intrusion systems• Up to 36 live images from ENVS cameras can be

viewed simultaneously• Up to 256 cameras can be used (license dependent)• Easy migration path from analog to digital systems• Camera resolution, frame rate, etc. can be set up to

match system requirements

The Symmetry software enables video imagesto be viewed, recorded and replayed from aninterface that has been designed for simplicityand ease of use.

Two versions of the software are available:"Symmetry Video Essentials" and the full"Symmetry Video Management" software.Table 3 on page 14 summarizes the features ofthe software, and the differences betweenproduct types.

The software provides an open platform thatsupports the ENVS, a wide range of DigitalVideo Recorders (DVRs) and IP cameras.

The module also supports interfaces to legacyanalog CCTV switchers, which facilitates an

easy upgrade from an analog to digital solutionat a later date.

There are two main screens: the Virtual Matrixscreen, which is used to view live video (Figure2-8), and the Video Playback screen, which isused to replay recorded video (Figure 2-9).A key feature of the software is its ability to"tag" an area of a recording. This prevents therecording from being overwritten and enableseasy playback. Tagging can be carried out by atrigger command (e.g. generated by an ENVSmonitor point), user recording or a user-applied"bookmark".

Note: Please refer to the User's Guide for anoverview of how to use the software.



Figure 2-8: Viewing Live Video in the Virtual Matrix Screen

Figure 2-9: Replaying Recorded Video in the Video Playback Screen



Symmetry – Key FeaturesTable 3: Features of Symmetry, and differences between Product Types

Differences between Product Types

Feature Symmetry VideoEssentials

Symmetry VideoManagement

Virtual Matrix screen – Simultaneouslydisplays multiple live images from digitalvideo cameras (Figure 2-8).Includes controls for camera pan, tilt, zoomand focus.Instant Record feature.Save, print and export images.

Up to 4 simultaneous liveimages per PC.

Up to 36 simultaneous liveimages per PC.Camera sequencing.Supports display of Webpages.Instant Replay feature.Alarm and activity display.

Video Playback screen – Allows easyreplay of video recordings (Figure 2-9).Filter options enable recordings to belocated quickly from the database.

Single recording replay. Simultaneous replay of upto four recordings.JPEG picture export.

Tagging – Tagged recordings producedby, for example, a Record Video triggercommand or user recording, are preventedfrom being overwritten and enable easyplayback.

Also supports tagging by auser-applied "bookmark"

Camera Support – A wide range ofcamera types is supported.Maximum number of cameras is licensedependent.

Supports ENVS, DVR andIP cameras.

Supports ENVS, DVR andIP cameras.

CCTV switcher integration – Camerasattached to legacy CCTV switchers can beviewed, controlled and switched to anymonitor. Ancillary devices (such as lampsand wipers) can be switched on or off.Commands – Commands can, forexample, run scheduled recordings andrecord incidents automatically (e.g. fromany intrusion or access event).

Supports commands toswitch live video to thevirtual matrix.

Playback from alarms or reports –Incidents recorded automatically by analarm or event can be easily replayed fromhistory reports or the View/Alarms screen.Graphics integration – Live video can beplayed from a graphic, such as a plan ormap of the building.



Features and Benefits – Video Storage Management Module

Figure 2-10: Storage Settings Screen

Key Selling Benefits

• Enables video from ENVS or network (IP)cameras to be saved to network storagedevices

• Facilitates ENVS "store-and-forward"function

• Provides out-of-hours forwarding of ENVSrecordings

• Allows video from Axis IP cameras to berecorded (MPEG-4 format must be used)

• Allows recording of video from an ENVSthat is not fitted with a hard disk

The Video Storage Management Module is acomprehensive video data managementsystem, which can automatically store videofrom an ENVS or Axis IP camera to networkstorage locations, such as a hard disk on a PC,or a Network Attached Storage (NAS) device.

The software facilitates the "store-and-forward"function of the ENVS, which transfersrecordings from the hard disk of an ENVS atconfigurable intervals to free disk space andenable archiving.

The software provides easy-to-use tools forsetting up the times and days that data will beforwarded, and the storage locations. If

required, multiple storage locations can bespecified to increase available disk space.

Policies for purging video from the storagelocations can also be set up, whichautomatically delete recordings that are olderthan a specified number of days.

The Video Storage Management Module isavailable "as standard" with the Symmetrysoftware to provide a Video Storage server onthe same PC as the database server. Ifrequired, additional licenses can be purchasedto install the software on other PCs if multipleVideo Storage servers are needed to handle alarge number of cameras (see page 18).

Video Storage Management Module – Key Features

A summary of key features of the Video Storage Management Module is given below.• Multiple storage locations can be defined• Available "as standard" on database server; additional Video Storage server licenses can installed• A priority system ensures that storage locations are used in a specified order• Choice of forwarding all recordings or tagged recordings only• Days and times of forwarding can be selected• Used, available and free disk space statistics can be easily displayed• Automatic purging of old recordings• Automatic alarm generation when free space reaches a specified limit

Note: Please refer to page 18 for machine requirements.

Note: The Video Storage Management Module does not retrieve data stored on a DVR.


3 Chapter 2: Computer Requirements

Requirements for the Symmetry Software

Note: Please refer to the Software Installation Manual for for general software requirements, such as thebackup software, email software, peripherals supported and USB ports required.

NOTE: Factors such as the resolution, frame rate, video format, quality, motion rate and picture detail affectthe amount of video data transmitted and the processing that the PC needs to carry out. The systemrequirements specified below assume low motion, moderate detail and the following camera settings:

� For ENVS cameras: 6 frames per second in D1 resolution (720x576 PAL; 720x480 NTSC). (This is thehighest recommended frame rate and resolution when 4 cameras are connected to an ENVS.)

� For IP cameras: 30 frames per second in 640x480 resolution, and a compression value of 50, usingMPEG-4 or Motion JPEG video. (This is the highest frame rate and resolution for an Axis 211 or 211A IPcamera.)

The system must be configured prior to live operation to prevent excessive loading of PC and networkresources. It is strongly recommended that trials take place before system roll-out to establish system loading.

Supported Operating Systems

Windows XP Professional with Service Pack 2, orWindows 2000 Professional with Service Pack 4, orWindows Server 2003 Standard Edition with Service Pack 1, orWindows Server 2003 R2 Standard Edition, orWindows 2000 Server with Service Pack 4 (SQL Server 2000/2005 database servers only)

Database Server or Standalone Machine RequirementsTable 4: Server Requirements

Max. number ofviewed cameras(live or recorded)

Server Type

ENVS IP

Min.processor

speed

Min. RAM Min. DiskSpace

MSDE database server, not usedto view live or recorded video

0 0 2GHz 512MB 80GB

MSDE database server, used todisplay live or recorded video

36 16 3.2GHz Dual-Core

2GB 80GB

Full SQL Server 2000/2005database server, not used to viewlive or recorded video

0 0 Please see the Software Installation Manual.This configuration is supported only when

Symmetry is integrated with access-control.

Computer Requirements


Note:

• The Video Storage Management Module (if used) requires enhanced machine specifications; seepage 18.

• On a Video Storage server, the number of cameras viewed (live or recorded) should not exceed 4.

• The quoted specifications are applicable only when using ENVS or IP cameras. Systemrequirements vary considerably when using DVR cameras, depending on DVR make and systemarchitecture. If the installation uses DVR cameras, trials must take place before system roll-out todetermine machine and network requirements.

• All processors must be Pentium 4 with hyper-threading.

• Maximum performance is achieved using 2GB or more of RAM.

• It is recommended that PCs used to display live or recorded video are not used to communicate withother devices, such as access-control nodes.

Client Requirements

Table 5: Requirements for any Machine Displaying Live or Recorded Video

Max. number ofviewed cameras(live or recorded)

Machine Type

ENVS IP

Min.processor

speed

Min. RAM Min. DiskSpace

4 N/A 2GHz 512MB 20GB

12 N/A 2.8GHz 1GB 20GB

Client-only machinedisplaying live or recordedvideo

36 16 3.2GHz 1GB 20GB

The notes given above also apply.

Graphics Card

A graphics card with at least 64MB of RAM is required if the PC displays live or recorded video. Anintegrated graphics card using system RAM is not recommended for this purpose. The following graphicscards have been tested for compatibility with the Digital Video Management module. If another card isfitted, it must be tested thoroughly before use.

NVIDIA GeForce MX4000 ATI Radeon 7000NVIDIA GeForce FX5200 ATI Radeon 9200NVIDIA GeForce 6200 ATI Radeon X600 SE

Network Capacity

It is important to determine the network bandwidth used by other applications and to check that there issufficient capacity to stream live video from the cameras. Please refer to page 31 for guidance.

Computer Requirements


Requirements for Video Storage Servers

Number of Video Storage Servers Required

The number of Video Storage servers required is dependent on a number of factors, including the numberof cameras that may be transferring video recordings to a Video Storage server at any one time, theamount of video data in those recordings (affected by frame rate or resolution) and the processing powerof the servers used. The number of Video Storage servers required is therefore site dependent and mustbe reviewed during system trials.

For initial system sizing, and using the machine specifications given below, it is recommended that a VideoStorage server processes video from no more than 64 cameras at any one time. If a server processesvideo from more than 32 cameras at any one time, it should be dedicated to the task, i.e. not used for otherCPU-intensive tasks such as to view live or recorded video. A Video Storage server should not be used toview live or recorded video from more than 4 cameras at a time.

Connection of Video Storage servers over a WAN is not recommended.

Windows Operating System

Windows 2000 and XP have a license limit of 10 concurrent FTP connections, which limits the number ofENVS units that can access a Video Storage server (for store-and-forward) to 10. Windows Server 2003Standard Edition (with Service Pack 1) is required if any Video Storage server that is managing more than10 ENVS units. If Windows Server 2003 is used, please check that all required peripherals are supportedunder this operating system.

Processor and RAM Requirements

Standalone Video Storage Server, or when used on an MSDE database server:

Processor: Pentium 4, 3.2GHz Dual-Core with Hyper-ThreadingMin RAM: 2GB

When used on a full SQL Server 2000/2005 database server:

Processor: Pentium 4, 3.8GHz Dual-XEONMin RAM: 3GB

Note: The Video Storage server software is always installed on the database server. If the database serveris not used to manage video recordings, the higher machine specifications to be a Video Storage serverare not required.

Server Disk Space

An additional 100GB of disk space is needed on each Video Storage server for temporary storage of videodata. A dedicated hard disk is recommended.

Network Attached Storage

Additional disk space is required for the storage of recorded video from ENVS or IP cameras. Please referto page 43 for guidance.


3 Chapter 3: Designing the System

This chapter describes the factors to consider when designing a digital video system. Factors relatingspecifically to the Video Storage Management Module are described in Chapter 4.

While you are working through this chapter, note the settings selected on the System Design Worksheets(page 47).

Overview of the IP Camera Configuration Screen

IP Cameras can be set up using the Install/Digital Video/IP Camera screen (Figure 3-1). The IP address,username and password of the camera must be set up using the separate configuration utility provided byAxis, and entered into the screen.

The Online Help gives full information about this screen.

Figure 3-1: IP Camera Screen

Designing the System


Overview of the DVR Setup Screens

Configuring a DVR is a two-stage process: define the DVR using the Install/Digital Video/DVR/VideoRecorder screen (Figure 3-2), then configure each camera using the Install/Digital Video/DVR/VideoCamera screen (Figure 3-3). The Online Help gives full information about these screens.

Figure 3-2: DVR Definition Screen

Figure 3-3: DVR Camera Definition Screen



Overview of Screens used for ENVS ConfigurationThe following screens are used to set up a system that uses ENVS devices:

• The Video Server screen – This defines each ENVS being used.• The ENVS Camera screen – This defines each ENVS camera being used.• The Storage Server Settings screen – This is applicable to Video Storage Management, and is

described in Chapter 4.

Using the Video Server Screen

The first step when setting up an ENVS system is to define each ENVS using the Install/DigitalVideo/ENVS/Video Server screen (Figure 3-4).

Figure 3-4: Video Server Screen

The screen contains a Discover button, which when selected for a new record, displays a list of allunconfigured ENVS devices located on the network (Figure 3-5). Once the ENVS has been selected in thelist (identified from its MAC or IP address), configuration of the ENVS can begin.



Figure 3-5: Selecting the ENVS to Configure

The IP address of the ENVS displayed at the top of the Video Server screen should have been definedalready during system installation using the ENVS Viewer Control (as described in the ENVS InstallationInstructions). The address should be static, since Symmetry will not able to locate an ENVS whose IPaddress is "floating". For this reason, Obtain IP Address Automatically (DHCP) should not be selected inthe Communications tab.

The ENVS configuration options are located in seven tabs, as shown in Table 6. This table provides cross-references for further information, but if you are reading this chapter for the first time, it is recommendedthat you read it in sequence.

Table 6: Tabs in the Video Server Screen

Tab Name Purpose Further InformationContains communication options, such as the networkspeed (Video Network Connection) and network type(Video Server Network Type). Selecting the correctvalues for these two options is important, since they affectdefault camera settings that influence the amount ofnetwork bandwidth used.

This chapter – page 33Communications

The lower part of the tab contains options forcommunicating with an optional Pan/Tilt/Zoom (PTZ)controller connected to the ENVS.

Online Help

Archive Specifies the schedules for forwarding video from the harddisk of the ENVS to a network storage device.

Chapter 4

Disk Specifies settings used to delete recordings from theENVS hard disk, warn of recordings that are overwritten,and for streaming video directly to a Video Storage server.

This chapter – page 30

Input/Output Enables the inputs and outputs of the ENVS to bespecified.


Overlay Defines the text to superimpose on the video images,such as camera name or date and time.


Date and Time Contains date and time options, such as for timesynchronization.


Reporting Specifies whether messages from the ENVS are reportedas alarms or events.

Online Help



Using the ENVS Camera Screen

Once an ENVS is defined, you can define each camera connected to the ENVS using the Install/DigitalVideo/ENVS/Camera screen (Figure 3-6).

The configuration options are located in five tabs, as shown in Table 7.

Table 7: Tabs in the ENVS Camera Screen

Tab Name Purpose Further InformationVideo Contains key settings for the camera, such as resolution

(Picture Size), frame rate (Picture Refresh) and target bitrate (Camera Data Rate). You can also display a livepicture from the camera to view the actual frame and datarates from the camera.

Throughout thischapter

Advanced Specifies additional settings that control network usageand picture quality. Although defaults are provided, theseare also important settings and can have a major impacton system performance.


Motion Detection Enables motion detection to be defined for the camera. This chapter – page 39Pan / Tilt / Zoom Enables preset positions to be defined for the camera. This chapter – page 40Reporting Specifies whether messages from the camera are

reported as alarms or events.Online Help

Figure 3-6: ENVS Camera Screen



Choosing the Camera Resolution

The setting to consider first is image resolution, which is measured in pixels and determines the clarity ofthe displayed or recorded image. Each camera can have a different resolution, which should be chosencarefully to match the intended purpose. Too low a resolution will result in pictures with insufficient detail.Too high a resolution can result in unnecessary network traffic, increased storage demand and slower PCperformance.

The resolution for an ENVS camera can be selected in the Video tab of the ENVS Camera screen (seepage 23); supported resolutions are shown in Figure 3-7. Figure 3-8 shows the relative sizes of theseresolutions.

If IP or DVR cameras are being used, please refer to the manufacturer's documentation for details ofsupported resolutions. The software provided with the IP camera or DVR should be used to set up thecamera resolution.

When selecting the resolution, consider the following points:

• Choose a resolution that matches the requirements of the intended application. For example, animage used to record a person's identity may require a higher resolution than an image used only toestimate traffic flow.

• CIF resolution is normally suitable for determining activity in the picture; if greater detail is needed, ahigher resolution is necessary.

• The resolution of computer monitors is typically 1024x768 pixels. A high resolution may be wasteful ifthe image is only ever displayed in a small area of the screen. A low resolution image displayed in alarge area of the screen will lose clarity.

PAL NTSCSee the nextsection fordetails ofresolutionstandards

Figure 3-7: Resolutions Supported for ENVS Cameras

In practice, images are often not displayed in the aspect ratios shown in Figure 3-7. For example, a CIFimage may be displayed in a window measuring 400x500 pixels. In this case, the image is resized to fit theaspect ratio of the window in which it is displayed. This can lead to some stretching or squashing of thepicture, but resizing can be switched on or off as required.

Note: Your initial choice of camera resolution may need to be revised once you have considered thenumber of cameras connected to the ENVS, used the "ENVS Hard Disk Drive and Network BandwidthEstimator" and checked network usage, as described later in this chapter.



D1

2CIF

CIF

QCIF

Figure 3-8: Relative Sizes of Selectable ENVS Resolutions

Background to Resolution Standards

Analog cameras transmit video in a composite format derived from the television industry. In NorthAmerica and Japan, the NTSC (National Television System Committee) standard is mainly used, whichhas 480 horizontal lines at a frame rate of 30fps. In Europe, the PAL (Phase Alteration by Line) standard isused, which has 576 horizontal lines at a frame rate of 25fps.

When the images are converted to a digital format, the resolution is often based on the number of TV linesto be digitized. When using this system, the maximum resolution is 704x480 pixels for NTSC and 704x576pixels for PAL.

In many security applications, four cameras share the maximum resolution. This quarter resolution isknown as CIF (Common Intermediate Format).

Common resolutions are:

4CIF: 704x480 (NTSC); 704x576 (PAL)2CIF: 704x240 (NTSC); 704x288 (PAL)CIF: 352x240 (NTSC); 352x288 (PAL)QCIF: 176x120 (NTSC); 176x144 (PAL)

Several new resolutions have been derived from the computer and DVD industry. Most common are:

D1 (DVD-Video): 720x480 (NTSC); 720x576 (PAL)VGA: 640x480QVGA: 320x240 This is sometimes known as SIF (Standard Interchange Format); not

to be confused with CIF



Choosing the Camera Frame Rate

The camera frame rate is measured in frames per second (fps) and determines the smoothness of thevideo pictures from the camera. "Full motion" images are normally regarded as requiring 25fps for PAL, or30fps for NTSC.

Higher frame rates increase picture smoothness, but as with higher resolutions, can result in unnecessarynetwork traffic, increased storage demand and slower PC performance.

Supported frame rates for cameras connected to an ENVS are shown in Figure 3-9. The frame rate(Picture Refresh) is selected in the ENVS Camera screen (see page 23).

If IP or DVR cameras are being used, please refer to the manufacturer's documentation for details ofsupported frame rates. The software provided with the IP camera or DVR should be used to set up theframe rate.

PAL NTSC

Figure 3-9: Frame Rates Supported for ENVS Cameras

Recommendations:

• Frame rates of 1 to 3fps are normal for general observation of lobby areas, office areas or where thepurpose of the CCTV recording is to provide a general level of observation.

• Frame rates of 4 to 7fps are common for areas of high throughput of people, moving vehicles, wherethe intent of the subjects being recorded need to be determined, or where it is necessary to capturethe facial images of moving people.

• Frame rates in excess of 10fps are used in applications where it is necessary to view or record highdegrees of motion, such as in casinos and traffic applications, or when audio needs to synchronizewith lip movement.

Note: As for resolution, the initial choice of frame rate may need to be revised once you have consideredother factors described in this chapter and in Chapter 4.



Checking ENVS Frame Rate/Resolution Capacity

The performance of an ENVS may be reduced if it has too many cameras with a high resolution and framerate. For this reason, it is important to check the selected settings using the procedure below beforefinalizing the resolution, frame rate and the number of cameras connected to a single ENVS.

When both the resolution and frame rate are set to the absolute maximum values, only a single camerashould be used. In this case, a single-channel ENVS may be a more appropriate solution.

To check the selected settings for each camera, multiply the frame rate by the factor from Table 8, thenadd the results. It is recommended that the total does not exceed 120 if NTSC cameras are used, or 100 ifPAL cameras are used.

Table 8: Resolution Multiplication Factors

Camera Resolution Multiplication FactorQCIF or CIF 12CIF or HD1 2

D1 4

Example:

Camera 1 (PAL): 2CIF @ 15fps = 2 x 15 = 30Camera 2 (PAL): CIF @ 25fps = 1 x 25 = 25Camera 3 (PAL): CIF @ 15fps = 1 x 15 = 15Camera 4 (PAL): 2CIF @ 15fps = 2 x 15 = 30TOTAL = 100 – Acceptable

The capacity check can be carried out automatically using the "ENVS Hard Disk Drive and NetworkBandwidth Estimator" (Figure 3-10), which is located in the Documentation folder on the Symmetryinstallation CD. The Estimator is a Microsoft Excel spreadsheet. There are two versions: one for PALcameras, and one for NTSC cameras.

Figure 3-10: Using the Estimator to Check ENVS Capacity

Specify theresolution, framerate and motionfactor for eachENVS camera.

This shows theresult of thecheck.



Selecting the Recording Policies

It is important to consider how often and under what circumstances recording should take place, since thiscan seriously affect the amount of disk space used for recordings and, if Video Storage Management isused, network activity when recordings are forwarded to network storage.

Using commands set up in the software, each camera can record:

• Continuously.• At scheduled times.• In response to a user command.• In response to a Record Video trigger command, which is activated by an alarm or event condition,

such as by motion detection or when the contacts of an ENVS monitor point are closed.

DVR cameras are normally set up to record continuously.

If IP or ENVS cameras are used, consider whether to use the Record Video trigger command to startrecording on motion detection or after an alarm/event, rather than continuously or at scheduled times.

When using an ENVS camera, the Record Video trigger command can make use of the ENVS "pre-eventbuffer", which is set up in the Advanced tab of the ENVS Camera screen (Figure 3-11). If you enable thebuffer and, for example, set its capacity to 60 seconds, the ENVS will always store the last 60 seconds ofvideo footage. Since a recording started by a Record Video trigger command can include the video in thepre-event buffer, the feature may reduce the need for continuous or scheduled recordings.

IP cameras do not normally have a pre-event buffer and therefore it is more likely that there is a need torecord continuously or at scheduled times. However, the Record Video trigger command can still be usefulin these cases. A Record Video trigger command "tags" the recording at the alarm/event time, and theperiod tagged can include time before the alarm/event if the camera records continuously. The benefit ofdoing this is that the system can be set up to purge the much larger untagged areas of a recording morefrequently than the tagged recordings, which reduces demand for disk space.

Figure 3-11: Enabling the Pre-Event Buffer for an ENVS



ENVS Disk Space

If video from an ENVS is not being archived using the Video Storage Management Module, it is advisableto use the ENVS Hard Disk Drive and Network Bandwidth Estimator to estimate the number of days ofrecorded video that can be stored on the ENVS hard disk (Figure 3-12). When the ENVS hard disk startsto become full, the system automatically overwrites recordings, starting with the oldest untaggedrecordings, followed by the oldest tagged recordings. Prolonged continuous recording will lead to high diskusage and may result in important recordings being overwritten and therefore stored for insufficient time.

The estimate is dependent on:

• The resolution and frame rate of each camera – Increasing the resolution and/or frame rateincreases the amount of video data and therefore reduces the amount of video that can be stored.Note that trigger commands can be set up to change the resolution or frame rate in response to analarm or event condition.

• The level of motion in the camera view – The greater the motion, the fewer the number of days ofvideo that can be stored, since the degree of compression of the video data reduces if there is moremotion. Note: Poor or noisy video signals, or rapid changes in lighting, are interpreted as motion andwill also increase storage demands.

When there is little or no movement (such as viewing an occasional person in a corridor) use amotion factor of about 2. When there is constant movement in the camera view, a setting of 10 isrecommended. To prevent an underestimate, avoid setting the figure too low.

• The size of the hard disk – This is 80GB.

Depending on the results from the Estimator, you may need to adapt the recording policy, or even re-examine the resolution and frame rates used.

Figure 3-12: Estimating the Number of Days of Recording

If video from an ENVS is being archived, ENVS disk space is generally not an issue, as space is freedwhen recordings are forwarded. Since the hard disk can record more than a day of continuous video(assuming the capacity check is not exceeded; page 27) and forwarding can occur every day, the results of

Gives the estimatednumber of days ofstorage for the ENVShard disk.



running the Estimator may be relevant only to determine how long the ENVS can store video in the event ofa network failure. An exception is when only tagged recordings are forwarded, which leaves any otherstandard recordings on the ENVS hard disk.

ENVS Disk Purging and Warnings

Selecting Automatically delete video recordings older than in the Disk tab of the Video Server screen(Figure 3-13) causes recordings older than a specified number of days to be automatically deleted. Youmay need to select this option in countries with privacy laws that disallow long-term storage of videorecordings. The limit should also be entered into the Purge tab of the Configure/Digital Video/Video ServerSettings screen (page 44).

The tab also contains Warn if... options than can produce an alarm/event message if a recording under aspecified number of days old is overwritten. It is good policy to set the time periods for these options towarn of cases when recordings are overwritten sooner than expected by the Estimator.

Figure 3-13: ENVS Disk Settings



Managing the Network

Viewing or streaming live video to a client PC running the Symmetry software can involve sending largeamounts of data across the network. To ensure adequate performance from all applications or devicesusing the network, including the digital video system itself, it is important to consider the amount of networkbandwidth used by live video transmissions. Wide Area Networks (WANs) generally have much lessavailable bandwidth than a Local Area Network (LAN), and therefore require special care.

In most cases, the digital video system will use an existing network. If an appropriate Ethernet switch isused, it is possible to add the system to a virtual LAN (VLAN), which may be able to be set up with abandwidth limit. Note that firewalls must be configured to allow video data to pass through. The digitalvideo system uses standard protocols such as HTTP and FTP, and therefore configuration should berelatively straightforward for an experienced network administrator.

The amount of network bandwidth used by the digital video system is dependent on the bit rate (alsoknown as the data rate) from each camera, in bits per second. The bit rate is a measure of thetransmission speed of binary data from the camera. A higher bit rate leads to greater network usage.Increasing any of the following will give a higher bit rate:

• The camera resolution.

• The camera frame rate.

• The amount of motion in the image.

• The image quality setting (also known as compression). Decreasing quality reduces the amount ofdigital data that needs to be transmitted, but can also reduce the decoded quality of the picture.

Network usage is generally not an issue if all of the following are true:

• Live video is rarely viewed.

• Live video is not streamed to a network storage device (using the Video Storage ManagementModule).

• Small amounts of recorded video are replayed after being forwarded to a network storage device.

Estimating ENVS Camera Network Usage

An estimate of network usage for an ENVS camera can be obtained using the Network Storage andSystem Bandwidth Estimator (Figure 3-14), which is located in the Documentation folder on the Symmetryinstallation CD. Enter the number of cameras, the frame rate and resolution to obtain an estimate ofnetwork usage in kbits per second. Default quality settings and the highest motion factor (10) are assumed.

Figure 3-14: Estimating Network Usage



An estimate is also displayed in the Camera Network Usage field of the ENVS Camera screen, as shownin Figure 3-15. The actual frame and bit rates can be displayed using the Live Picture option (page 35).

Figure 3-15: Estimated Network Usage from the ENVS Camera Screen

Estimating IP or DVR Camera Network Usage

Please refer to the manufacturer's documentation for details of network usage for IP or DVR cameras. Foran IP camera at 640x480 resolution and a compression level of 50, approximately 4.8% of a 100Mbits/snetwork is used for each camera. The Axis web site provides a bandwidth calculator.

Reducing Network Usage

Reasons for reducing bandwidth may include the following:

• The network may be used for other business-critical applications. Bandwidth available for theseapplications may need to be protected to prevent loss in performance.

• Many ENVS devices sharing the same network may overload the network, which can result in picturebreak-up. In some cases, the available bandwidth may not be predictable, and bandwidth may beseverely restricted at certain times, such as when using a Wide-Area Network (WAN).

Bandwidth usage can be reduced or limited using a number of methods, all of which control the bit rate:

• The resolution and/or frame rate can be reduced.

• The camera position can be changed to reduce the amount of motion in the image.



• For ENVS cameras, the target bit rate and quality can be reduced manually in the ENVS Camerascreen (Figure 3-16 and Figure 3-17). The exact effect of changing the bit rate and quality settingsdepend on the Bit Rate Mode (Figure 3-17), which can have any one of the following three settings:

− Constant: Causes the ENVS to change the quality of the picture between Min Quality and MaxQuality to prevent the bit rate exceeding the value specified by the Bit Rate option. The systemattempts to use the highest quality, which often means that the bit rate is reasonably constantaround the specified bit rate. If the minimum quality is reached, the frame rate is reduced tomaintain the bit rate budget. Instantaneous changes to the bit rate are limited by the Bit RateCap setting, which should be at least 30% greater than Bit Rate.

The Constant bit rate mode should be used if a strict bandwidth budget needs to be imposed.This setting is the default when the network type is a WAN (as specified in the Video Serverscreen), since bandwidth on a WAN may be very limited at certain times.

− Average: This is similar to Constant, except that Bit Rate Cap is not used, and if the minimumquality is reached, the frame rate will not be reduced. The bit rate may therefore exceed thebudget. The Average bit rate mode is the default when the network type is a LAN, as specifiedin the Video Server screen.

− Variable: This should not be used to control bandwidth, since the bit rate is allowed to fluctuateas required depending on the current resolution, frame rate and motion. The quality of thepicture is fixed using the Quality setting. The bit rate is capped using the Bit Rate Cap setting,which if reached causes the frame rate to be reduced.

Figure 3-16: Setting the Target Bit Rate

Selecting Set Data Rate Manually enables you to specify the target bit rate (Camera Data Rate).

The default value is calculated from camera settings such as resolution (Picture Size) and frame rate(Picture Refresh). When defining a new camera, if the calculated value is greater than the network speedspecified in the Video Server screen, the bit rate is capped at the network speed and you are warned thatmore bandwidth than available is being used. In this case, reduce the resolution or frame rate.



Figure 3-17: Advanced Camera Settings (Quality and Bit Rate Mode)

Note: Reducing the bit rate will reduce the amount of disk space used, as well as reducing network usage.

Changing the ENVS I-Frame Interval

A video transmission consists of one or more sets of frames. Each set starts with an I-Frame followed by aseries of P-Frames. An I-Frame is a complete picture at a point in time. Each P-Frame specifies only thechanges in the video picture from the previous frame. An I-Frame can contain much more data than a P-Frame, since a P-Frame contains only the data that has changed.

The I-Frame Interval option in the Advanced tab of the ENVS Camera screen can be used to increase theinterval between I-Frames, which reduces the ratio of I-Frames to P-Frames and the overall amount ofdata transmitted. You may want to do this to reduce the bit rate and network usage, but note that fewerI-Frames leads to the picture being refreshed less often, which can cause undesirable effects if the videosignal is poor. This setting applies to both live and recorded video, and therefore disk space should also bereduced by increasing the I-Frame interval.

If you select Limit Live Video Frame Rate to in the Advanced tab, live video viewed or streamed acrossthe network will contain only I-Frames. This reduces the live frame rate to the value set in the I-FrameInterval option and therefore reduces network usage, but does not affect the frame rate of video recordedon the hard disk of the ENVS. The option can be very useful if it is not necessary to display live video at thesame frame rate as recorded.



Viewing the Actual Frame and Bit Rates for an ENVS Camera

The current frame rate (Picture Refresh) and bit rate (Current Data Rate) achieved using the selectedsettings, camera position and motion can be tested by selecting Live Picture in the Video tab of the ENVSCamera screen (Figure 3-18).

Figure 3-18: Viewing the Actual Frame and Bit Rates

Similar information is available from the View/Status screen (Figure 3-19).

Figure 3-19: ENVS Camera Settings Displayed using View/Status

Display theframe rate andbit rate actuallyused



Specifying ENVS Inputs and Outputs

Each ENVS has four monitor-point inputs and two auxiliary outputs.

Auxiliary outputs can be used to switch external devices on or off by a manual, scheduled or triggercommand.

The monitor points can be connected to sensors such as infra-red detectors, floor pads, door contacts orsimilar devices. The inputs are constantly monitored, and can be used in trigger commands to perform apredefined function, such as to start recording or switch on an auxiliary output.

The monitor points and auxiliary outputs can be defined in the Input/Output tab of the Video Server screen(Figure 3-20). The system design phase should consider the number of inputs and outputs required.

Figure 3-20: Setting up the ENVS Inputs and Outputs

The description should be left blank for any input or output not used.



Specifying the ENVS Overlay Information

Using the Overlay tab of the Video Server screen (Figure 3-21), up to four items of information can besuperimposed over the video from each camera. These are the date, time, camera name and fixed text.Both the position and size of the text can be specified.

During the design phase, the type of information to superimpose should be considered. Date and time arenormally included to provide date/time stamping for recordings. The information will appear on both liveand recorded video.

Figure 3-21: Setting up the ENVS Overlay Information



Synchronizing the ENVS Date and Time

Consideration should be given to the method used to keep the ENVS date and time up to date. By default,the ENVS time is synchronized with that of the server. However, an SNTP (Simple Network Time Protocol)server can be used if a more accurate method of maintaining the correct time is required. It isrecommended that the server, all clients and all ENVS units use an SNTP server.

The ENVS data and time settings are specified in the Date and Time tab of the Video Server screen(Figure 3-22).

Figure 3-22: Setting up the Time Synchronization Options

The Enable Simple Network Time Protocol (SNTP) option should be selected if an SNTP server is used.The names or IP addresses of up to two SNTP servers can be specified (Preferred Server and AlternateServer). Alternative Server is used only if Preferred Server is not available.

By default, the time is obtained every hour from an SNTP server and is updated only if the time differenceis greater than 2 seconds.

Please refer to the Software Installation Manual for details of setting up a Windows Time Server SNTPserver.

Selection of the correct Time Zone ensures that the ENVS automatically updates its time when there is adaylight-saving time change.



Setting Up Motion Detection

The ENVS gives the capability of setting up 20 motion detection zones for each camera (Figure 3-23),which can automatically detect and report movement in the defined zone. A trigger command can be set upto record video when motion is detected.

Motion detection may influence system design, since the need to record continuously may be regarded asunnecessary if motion detection is used.

Figure 3-23: Motion Detection Options



Specifying the PTZ Controls and Presets for an ENVS Camera

If a PTZ controller is connected to the ENVS, the Pan / Tilt / Zoom tab of the ENVS Camera screen (Figure3-24) should be used to specify:

• The controls available for the camera (pan, tilt, zoom, focus). All selected controls will be madeavailable to an operator when viewing live video.

• The camera preset positions. A preset defines a set position for a camera. When viewing live video,an operator can click a preset button to move the camera automatically to the predefined position. APTZ Preset command can also perform the same task.

When the controls and presets are defined, consideration should be given to the effects of the variousfields of view on camera bit rate. A view that contains more motion will result in a higher bit rate and greateruse of disk space, as described earlier in this chapter.

Figure 3-24: Setting up Camera Presets


4 Chapter 4: Video Storage

This chapter describes design considerations when using the Video Storage Management Module.

The Video Storage Management Module is a comprehensive video data management system, which canautomatically store video from an ENVS or Axis IP camera to a network storage location. The softwarefacilitates the "store-and-forward" function of the ENVS, which transfers recordings from the hard disk of anENVS at configurable intervals to free disk space and enable archiving.

Choosing ENVS Video Forwarding Schedules

If ENVS cameras are being used, you need to specify schedules for forwarding recorded video from thehard disk of the ENVS to a network storage location. This is achieved using the Archive tab of the VideoServer screen (Figure 4-1).

Forwarding video frees disk space on the ENVS, as well as enabling the recordings to be stored in alocation that can be backed up or archived using normal backup/archive procedures. It is normal to forwardevery day, but if there is a reason for not doing so, the schedules may be influenced by the results ofrunning the "ENVS Hard Disk Drive and Network Bandwidth Estimator" (page 29).

Figure 4-1: ENVS Video Forwarding (Archiving) Schedules

Video Storage


Select a time for forwarding when few users or other applications need the network. Large amounts ofvideo data from many ENVS units can generate a lot of network traffic, and selecting an appropriate timewill reduce any impact.

The setting for Include Standard Recordings should be considered carefully:

• When the option is selected, all tagged and untagged (standard) recordings are forwarded to thestorage location, which can consume large amounts of disk space. The next section in this chapterdescribes how to estimate the disk space required.

• When the option is not selected, only tagged recordings are forwarded, which should significantlyreduce the amount of disk space needed. In this case, all untagged (standard) recordings will remainon the hard disk of the ENVS for a period of time that can be estimated using the "ENVS Hard Diskand Network Bandwidth Estimator" (page 29), which is available in the Documentation folder of theSymmetry Installation CD. The Estimator should be used to confirm that the time period is sufficient.

Video Storage


Estimating Required Network Disk Space

Consideration must be given to the amount of disk space needed to store recordings in the networkstorage location(s). Due to the large amounts of data involved, it may be necessary to provide one or morededicated network storage devices. Any TCP/IP addressable drive can be used, such as a hard disk on aPC, or a Network Attached Storage (NAS) device. NAS devices attach directly to the LAN and areoptimized for storing large amounts of data.

When using ENVS cameras, the ENVS can be set up to forward only tagged recordings, or all recordings,as described in the previous section. This setting may have a major impact on the amount of disk spacerequired. If the ENVS has no hard disk, live video can be streamed to the storage location. When using IPcameras, all recordings are streamed to the network storage location.

Note: All streamed or forwarded video is routed through an allocated Video Storage server.

You can use the following procedure to estimate the amount of disk space needed.

Estimating Required Network Disk Space

1. For each camera, estimate the number of hours of recording that are to be forwarded (or streamed)to the storage location in one day.

2. Use the "ENVS Hard Disk Drive and Network Bandwidth Estimator" to estimate the amount of diskspace needed to store the daily recordings from each ENVS camera. See Figure 4-2. Although theEstimator provides an estimate of ENVS disk usage, the results will be approximately the same fornetwork disk usage.

3. If Axis IP cameras are used, please refer to the Axis "Design Tool" on the Axis web site(www.axis.com/products/video/design_tool/Calculator.htm) to determine the storage requirements.

4. Add the daily disk space requirements for each camera to obtain a total for all cameras.

5. Multiply the result by the number of days the recordings need to be stored. This must be specified inthe Purge tab of the Configure/Digital Video/Video Server Settings screen (Figure 4-3), and can bedifferent for standard and tagged recordings. Recordings that exceed this limit are purgedautomatically.

This gives the estimated total disk space required. However, sufficient additional capacity should beprovided to allow for increased demand or changes to picture detail, motion or camera settings.

Note:

� The amount of disk space used should be monitored carefully, and if necessary, additional diskspace added.

Video Storage


Figure 4-2: Estimating Network Disk Space Requirements for ENVS Cameras

Figure 4-3: Schedules for Purging Video Recordings

Note: (1) Video recordings stored on the database server can be backed up and archived using theTools/Backup and Tools/Archive screens. (2) The time periods for purging may be influenced by legalrestrictions concerning the length of time recordings can be stored. (3) The purge schedules can bedifferent for each Video Storage server.

Specify theresolution, framerate and motionfactor for eachENVS camera.

The total diskusage per hour isdisplayed here.

Video Storage


Assigning Each ENVS and IP Camera to a Storage Server

The system can be set up to use one or more Video Storage servers. A Video Storage server is provided"as standard" on the database server. If required, licenses for additional Video Storage servers can bepurchased.

After the Video Storage servers have been installed (as described in the Software Installation Manual), andthe ENVS devices and IP cameras defined, each ENVS and IP camera must be assigned to a VideoStorage server using the ENVS & IP Cameras tab of the Configure/Digital Video/Storage Server Settingsscreen (Figure 4-4).

Please refer to page 18 for recommendations concerning the number of Video Storage servers to use.

Figure 4-4: Assigning ENVS Devices and IP Cameras to a Video Storage Server

Video Storage


Storage Folders

The locations where video recording are stored on the network are specified in the Storage Folders tab ofthe Configure/Digital Video/Storage Server Settings screen (Figure 4-5). There can be more than onestorage folder, and each can be located anywhere on the network.

When you add a storage folder, you specify the maximum amount of disk space for that folder. The folderlisted at the top of the Storage Folders tab is used first. When the available space at this location is full, thenext folder in the list is used.

Figure 4-5: Folders used to Store Video Recordings


5 System Design Worksheet

Location Reference:

ENVS Camera Setup:ENVS Camera Number

1 2 3 4Camera NameResolutionFrame Rate (fps)ENVS Capacity Check OK (Yes/No)For each camera, multiply the frame rate by thefactor given below, then add the values. The totalshould not exceed 100 (PAL) or 120 (NTSC).QCIF/CIF = 12CIF/HD1 = 2D1 = 4Main Recording Policy(Continuous, Scheduled, Triggered or Mixture)Pre-Event Buffer Time (Seconds)Motion Factor (1 = No Motion to 10 = Constant)Pan/Tilt Control (Yes/No)Focus Control (Yes/No)Zoom Control (Yes/No)

ENVS Setup:Setting

IP Address (Static)Estimated Storage Period of Recordings on ENVSHard Disk (Hours)Automatically Delete Video Recordings Older Than(Days)Number of Monitor Points Used (0-4)Number of Auxiliary Outputs Used (0-2)Overlay Details

SNTP Server Names or IP Addresses (if used)Name of Video Storage Server (if used)

Video Storage


IP Camera Setup:Camera

1 2 3 4 5Camera NameIP Address (Static)ResolutionFrame Rate (fps)CompressionVideo StorageServer (if used)

Network Usage for Live Video:ENVS Camera Number

1 2 3 4Network Type (LAN or WAN)Network Speed (kbps / Mbps)Total Permitted Bit Rate (kbps / Mbps)Bit Rate Mode (Constant, Average or Variable)ENVS only. Default is Constant for WAN, Average for LAN

I-Frame Interval (Seconds)ENVS only. Default is 1.Selection of "Limit Live Frame Rate to" (Yes/No)ENVS only. Default is No.

Estimated Bit Rate (kbps / Mbps)Total Estimated Bit Rate (kbps / Mbps)Sum of above; this should not be more than total permitted.

Tested Bit Rate (kbps / Mbps)ENVS only.

Total Tested Bit Rate (kbps / Mbps)ENVS only. Sum of above.

Video Storage Management Module:Setting

Forward Each Day (Yes/No)ENVS only. Default is Yes. If No, specify days.

Time of Day to ForwardENVS only. Default is 2am.

Include Standard Recordings (Yes/No)ENVS only. Default is Yes; recommend No if possible.

Total Estimated Network Disk Space (GB)Purge Standard Recordings Older Than (Days)Purge Tagged Recordings Older Than (Days)

Digital Video Design Guide i

6 Index

22CIF .................................................................................................................................................................... 25

44CIF .................................................................................................................................................................... 25

AAnalog video ......................................................................................................................................................... 4Archive.......................................................................................................................................................... 41, 44Automatically delete video recordings older than ............................................................................................... 30Auxiliary outputs ................................................................................................................................................. 36Average bit rate mode ........................................................................................................................................ 33

BBackup................................................................................................................................................................ 44Bit rate .......................................................................................................................................................... 31, 33

Actual/Tested.................................................................................................................................................. 35Estimated for ENVS camera........................................................................................................................... 31Estimated for IP or DVR camera .................................................................................................................... 32

Bit rate cap.......................................................................................................................................................... 33Bit rate mode ...................................................................................................................................................... 33

CCamera support.................................................................................................................................................. 14CCTV switcher.......................................................................................................................................... 4, 12, 14CIF ...................................................................................................................................................................... 25Constant bit rate mode ....................................................................................................................................... 33

DD1 ....................................................................................................................................................................... 25Data rate ...............................................................................................................................................See Bit rateDate and time ..................................................................................................................................................... 38DHCP.................................................................................................................................................................. 22Digital Video

Benefits............................................................................................................................................................. 6Introduction ....................................................................................................................................................... 4

Digital Video Management ModuleFeatures.......................................................................................................................................................... 14Machine requirements .................................................................................................................................... 16

Digital Video softwareIntroduction to ................................................................................................................................................. 12

Discover.............................................................................................................................................................. 21Disk space

ENVS.............................................................................................................................................................. 29Network........................................................................................................................................................... 43

DVRFeatures supported ........................................................................................................................................ 11Introduction to ................................................................................................................................................. 10Makes and models supported ........................................................................................................................ 10Network usage................................................................................................................................................ 32

Index

ii Digital Video Design Guide

Setup ...............................................................................................................................................................20

EENVS

Auxiliary outputs ..............................................................................................................................................36Capacity check ................................................................................................................................................27Date and time ..................................................................................................................................................38Disk settings ..............................................................................................................................................30, 31Disk space.......................................................................................................................................................29Features ............................................................................................................................................................7Forwarding.................................................................................................................................................15, 41Hard Disk and Network Bandwidth Estimator .................................................................................................29Introduction to....................................................................................................................................................7IP address .......................................................................................................................................................22Monitor points ..................................................................................................................................................36Motion detection ..............................................................................................................................................39Network usage.................................................................................................................................................31Overlay ..............................................................................................................................................................8Overlay tab ......................................................................................................................................................37Overview of........................................................................................................................................................4PTZ settings ....................................................................................................................................................40Purging disk space ..........................................................................................................................................30Recording capacity ..........................................................................................................................................29SNTP server ....................................................................................................................................................38Warning messages .........................................................................................................................................30

ENVS Camera screen .........................................................................................................................................23

FForwarding.....................................................................................................................................................15, 41Frame rate

Actual/Tested...................................................................................................................................................35Recommendations ..........................................................................................................................................26

GGraphics ..............................................................................................................................................................14Graphics card ......................................................................................................................................................17

II-Frame..................................................................................................................................................................6I-Frame Interval ...................................................................................................................................................34Include Standard Recordings ..............................................................................................................................42IP address

ENVS...............................................................................................................................................................22IP camera ........................................................................................................................................................19SNTP servers ..................................................................................................................................................38

IP cameraFeatures ............................................................................................................................................................9Features supported .........................................................................................................................................11Introduction to................................................................................................................................................4, 9IP address .......................................................................................................................................................19Network usage.................................................................................................................................................32Setup ...............................................................................................................................................................19Streaming ........................................................................................................................................................43

LLAN......................................................................................................................................................................33Limit Live Video Frame Rate to ...........................................................................................................................34

MMAC address.......................................................................................................................................................21Machine requirements.........................................................................................................................................16

Index

Digital Video Design Guide iii

Monitor points ..................................................................................................................................................... 36Motion detection ....................................................................................................................................... 8, 28, 39Motion factor ....................................................................................................................................................... 29MPEG-4................................................................................................................................................................ 6MSDE ................................................................................................................................................................... 5

NNetwork Attached Storage (NAS)....................................................................................................................... 43Network camera ..............................................................................................................................See IP cameraNetwork failure.................................................................................................................................................... 29Network storage ................................................................................................................................................. 41Network usage.................................................................................................................................................... 31NTSC.................................................................................................................................................................. 24

OOverlay ........................................................................................................................................................... 8, 37

PPAL..................................................................................................................................................................... 24Pan, tilt, zoom controls ....................................................................................................................................... 40P-Frame................................................................................................................................................................ 6Picture refresh ............................................................................................................................... See Frame ratePicture size ..................................................................................................................................... See ResolutionPre-event buffer .................................................................................................................................................. 28Processor ........................................................................................................................................................... 18PTZ controller ..................................................................................................................................................... 22Purge

From ENVS .................................................................................................................................................... 30From network storage..................................................................................................................................... 44

QQCIF ................................................................................................................................................................... 25Quality................................................................................................................................................................. 33

RRecord Video trigger command.......................................................................................................................... 28Recording policies .............................................................................................................................................. 28Resolution

Recommendations.......................................................................................................................................... 24Standards ....................................................................................................................................................... 25

SSMS software ....................................................................................................................................................... 5SNTP .................................................................................................................................................................. 38SQL Server ........................................................................................................................................................... 5Standard recording ............................................................................................................................................. 42Status screen...................................................................................................................................................... 35Storage folders ................................................................................................................................................... 46Storage server settings....................................................................................................................................... 46Store and forward ............................................................................................................................................... 15Symmetry

Overview of....................................................................................................................................................... 4Video Essentials ............................................................................................................................................... 5Video Management........................................................................................................................................... 5

System design worksheets................................................................................................................................. 47

TTagged recording ......................................................................................................................................... 12, 29

VVariable bit rate mode......................................................................................................................................... 33Video Cassette Recorder ..................................................................................................................................... 4

Index

iv Digital Video Design Guide

Video Essentials ............................................................................................................................................12, 14Video Network Connection ..................................................................................................................................22Video Playback screen ..................................................................................................................................13, 14Video Server Network Type.................................................................................................................................22Video Server screen

Overview..........................................................................................................................................................21Video Storage Management Module

Features ..........................................................................................................................................................15Forwarding schedules .....................................................................................................................................41Introduction......................................................................................................................................................15Machine requirements.....................................................................................................................................18Setting up ........................................................................................................................................................41

Virtual Matrix screen......................................................................................................................................13, 14

WWAN....................................................................................................................................................................33Windows........................................................................................................................................................16, 18

Documents

Digital Video Design Guide