Design and Installation Guide Avigilon License Plate Recognition System Version 1.3 920-0028A-Rev3
Copyright 1/19/12 Avigilon. All rights reserved. No copying, distribution, publication, modification, or incorporation of this document, in whole or part, is permitted without the express written permission of Avigilon. In the event of any permitted copying, distribution, publication, modification, or incorporation of this document, no changes in or deletion of author attribution, trademark legend, or copyright notice shall be made. No part of this document may be reproduced, stored in a retrieval system, published, used for commercial exploitation, or transmitted, in any form by any means, electronic, mechanical, photocopying, recording, or otherwise, without the express written permission of Avigilon. Avigilon has made every effort to identify trademarked properties and owners on this page. All brands and product names used in this document are for identification purposes only and may be trademarks or registered trademarks of their respective companies. Avigilon Tel +1.604.629.5182 Fax +1.604.629.5183 http://www.avigilon.com Revised 1/23/12
Table of Contents Introduction.................................1 Site Design..................................2 Overhead Mounting..............................2 Roadside Mounting...............................3 Maximum Vehicle Speed..........................4 Field of View....................................4 LPR Camera Selection............................5 NVR Processing Requirements.....................5 Installation..................................6 Package Contents................................6 Power Requirements.............................6 Mounting the LPR Camera Enclosure................6 Mounting PSU...................................7 Connecting Data and Power to LPR Camera Enclosure..7 Positioning the LPR Capture Kit.....................8 Software Configuration............................9 Verification Test................................10 Specifications..............................12 Outline Dimensions..............................13 Appendix of Images.........................14
Introduction The purpose of this guide is to detail how to design and install a License Plate Recognition (LPR) system using the Avigilon HD LPR Capture Kit. The first section, Site Design on page 2, covers possible mounting locations and equipment selection. The second section, Installation on page 6, covers the physical installation of the LPR Capture Kit, configuring the software, and a simple test to verify that the system is functioning properly. 1
Site Design The Avigilon HD LPR Capture Kits are designed to cover a single traffic lane of 10 ft (3 m) or two adjacent traffic lanes for a total of 20 ft (6 m). For each LPR Capture Kit, a mounting location must be selected. The kit can be mounted in either the overhead or roadside position. Overhead Mounting In overhead mounting, the LPR Capture Kit is mounted directly above the vehicle path. Table 1 lists the recommended mounting height and Table 2 lists the maximum mounting height for each LPR Capture Kit model. Refer to Figure A: Overhead mounting (top view) and Figure B: Overhead mounting (side view). Table 1: Overhead Recommended Mounting Height LPR Capture Kit Model Target Distance Recommended Mounting Height Horizontal Distance 1L-HD-LP-35 35 [11] 9 12 [2.8 3.6] 33 [10] 1L-HD-LP-50 50 [15] 13 17 [4.0 5.2] 48 [14.5] 1L-HD-LP-75 75 [23] 19 26 [5.9 7.8] 72 [22] 1L-HD-LP-100 100 [30] 26 34 [7.9 10] 95 [29] 2L-HD-LP-40 40 [12] 10 14 [3.1 4.2] 38 [11.5] Table 2: Overhead Maximum Mounting Height LPR Capture Kit Model Target Distance Maximum Mounting Height Horizontal Distance 1L-HD-LP-35 35 [11] 18 [5.5] 30 [9.2] 1L-HD-LP-50 50 [15] 25 [7.5] 43 [13] 1L-HD-LP-75 75 [23] 38 [11] 65 [20] 1L-HD-LP-100 100 [30] 50 [15] 87 [26] 2L-HD-LP-40 40 [12] 20 [6.1] 35 [11] 2
Figure A: Overhead mounting (top view) Figure B: Overhead mounting (side view) Roadside Mounting In roadside mounting, the kit is not directly above the vehicle path and is often pole-mounted on the side of the road. Table 3: Roadside Mounting Height and Offset lists the maximum mounting height and maximum offset distance for each LPR Capture Kit model. Select the shortest target distance that results in a practical mounting location. Refer to Figure C: Roadside mounting (top view) and Figure D: Roadside mounting (side view). NOTE: The dual lane kit should not be mounted in the roadside position. Table 3: Roadside Mounting Height and Offset LPR Capture Kit Model Target Distance Max Mounting Height Max Offset Horizontal Distance 1L-HD-LP-35 35 [11] 12 [3.6] 12 [3.6] 32 [10] 1L-HD-LP-50 50 [15] 17 [5.2] 17 [5.2] 46 [14] 1L-HD-LP-75 75 [23] 26 [7.8] 26 [7.8] 69 [21] 1L-HD-LP-100 100 [30] 34 [10] 34 [10] 93 [28] 3
Figure C: Roadside mounting (top view) Figure D: Roadside mounting (side view) Maximum Vehicle Speed The Avigilon HD LPR Capture Kit can recognize vehicles travelling at up to 60 mph (100 km/h) when mounted in the overhead position at the recommended mounting height. The maximum speed is limited to 40 mph (65 km/h) when mounted in the overhead position at the maximum mounting height or when mounted in the roadside position. Tip: To increase accuracy at high speeds (greater than 40 mph [65 km/h]), install the camera in the overhead position at the lowest recommended mounting height and the shortest target distance that is practical (See Table 1: Overhead Recommended Mounting Height). Field of View The field of view is the physical area that is visible in the image. It is important that there are no objects with high detail in the field of view when a vehicle is not present. For example, if the LPR camera is installed on the shoulder of a highway, it is important that the field of view be limited to a single lane and that the camera cannot see into other lanes. This will prevent it from generating incorrect results. Important: When a vehicle is not in view, the image should not contain anything that could be interpreted as a series of alphanumerics or any objects with high detail. 4
LPR Camera Selection Select the HD LPR Capture Kit based on the determined target distance. Table 4: Camera Selection Based on Target Distance Target Distance Single Lane Dual Lanes 35 [11] 1L-HD-LP-35 50 [15] 1L-HD-LP-50 75 [23] 1L-HD-LP-75 100 [30] 1L-HD-LP-100 40 [12] 2L-HD-LP-40 NVR Processing Requirements Avigilon LPR software should only be run on Avigilon NVR Servers or machines with similar specifications. For Avigilon NVR Servers, it is recommended to purchase an additional processor to supplement the high computational requirements of LPR. The maximum number of LPR lanes that can be enabled on a single server depends on the target vehicle speed and the mounting position. Table 5: NVR Processing Requirements Speed (mph [km/h]) Maximum number of lanes per NVR (Recommended Overhead) Maximum number of lanes per NVR (Maximum Overhead or Roadside) 0-20 [0-32] 4 2 20-30 [32-50] 2 1 30-40 [50-650 1 1 40-60 [65-100] 1 Not recommended 5
Installation Package Contents LPR Enclosure HD LPR Camera and Lens Power Supply Unit (PSU) Enclosure Wall Mount Camera Power Connector 3 mm Hex Tool Camera Mount Shims (Single Lane only) Shim mounting screws Power Requirements The LPR Capture Kit requires 78 W plus an additional 6 W for an overview camera. The following power transformer type is recommended: Recommended Transformer: 24 V secondary, 100 VA or higher. Figure E: System Diagram Mounting the LPR Camera Enclosure Install the enclosure and the enclosure mount in the location determined in the previous section. Caution Do not tilt the enclosure backwards with the back removed. It is possible for the camera to slide out. 6
Mounting PSU The distance between the LPR Camera Enclosure and the PSU is limited by the maximum length of the IR power cables. See the following table in reference to Figure E: System Diagram. Table 6: Wire Gauge vs. Distance Wire gauge Max Distance AWG (m) (ft) 18 4.0 13 20 2.5 8.4 22 1.6 5.3 24 1.0 3.3 Install the PSU within the maximum distance using the 4 x M4 mounting holes. Do not connect power to the PSU yet. Connecting Data and Power to LPR Camera Enclosure 1. Terminate the network cable after passing it through the environmental glands. Connect the network cable to the camera. 2. If the camera is not powered using PoE, wire camera power from the 24 VAC/DC supply to the included terminal-block connector. Insert connector into the camera. 3. Connect power to the IR panels using the wire gauge determined in Table 6: Wire Gauge vs. Distance and the wiring diagram in Figure F: Wiring Diagram. 4. Do not adjust any of the potentiometers in the PSU. 5. After the IR panels have been wired, connect input power to the PSU (terminals L and N ). There should be a red glow from each IR panel. If only 1 panel is glowing, immediately disconnect input power to the PSU and check the wiring. 7
NOTE: The environmental glands are designed for cables between 0.15 0.30 inches (4 8 mm) in diameter. For thinner cables, thicken the cable with electrical tape at the gland to ensure a tight fit. Unused glands should be plugged or sealed. Figure F: Wiring Diagram Positioning the LPR Capture Kit Avigilon HD LPR Capture Kits are pre-calibrated for a specific distance as indicated in the model number. It is important to accurately aim the camera to this distance. Use the horizontal distance determined when measuring the mounting position. When the LPR kit is mounted in the roadside position, vehicle license plates may not appear horizontal in the captured image (see Figure G: Rotated License Plate (Incorrect)). For high accuracy, it is important that license plates are oriented horizontally in the image as in Figure H: Horizontal License Plate (Correct). To compensate, the included shims can be placed between the enclosure and mount interface. The shims should be placed under 2 screws on either the left or right side of the interface. If the LPR kit is mounted on the right side of the road, shims should be installed on the left side of the enclosure/mount interface, and vice versa for the left side. 1. Park a vehicle in the centre of the target zone. 2. View the image of the vehicle. If the image is horizontal, you do not need to install the shims. 3. If the vehicle s license plate is not horizontal in the image, replace the 2 screws in the base with the shim mounting screws on the side that needs to be corrected. Do not tighten. 4. Install a shim under each of the mounting screws between the enclosure and the mount. Repeat until the license plate is horizontal in the image. Up to 3 shims per screw may be necessary. 5. Tighten the screws at the enclosure/mount interface. 8
Important: If using roadside mounting, the included shims must be installed so that license plates are horizontal in the image. Figure G: Rotated License Plate (Incorrect) Figure H: Horizontal License Plate (Correct) Software Configuration For more information about each step in the the following procedure, see the Avigilon Control Center Client User Guide. 1. In the Avigilon Control Center Client software, configure the License Plate Recognition options in the server Setup dialog box. 2. In the LPR camera Setup dialog box, click Compression and Image Rate and set the following options a. Set the Image Quality to 4. 9
b. Set the Image Rate according to the camera mounting position and estimated vehicle speed. Speed (mph [km/h]) Minimum Frame Rate (ips) (Recommended Overhead) Minimum Frame Rate (ips) (Maximum Overhead or Roadside) 0 20 [0 32] 5 10 20 30 [32 50] 10 15 30 40 [50 65] 15 24 40 60 [65 100] 24 Not Recommended Verification Test After the LPR Capture Kit has been installed and the software has been configured correctly, a simple verification test should be performed. Before performing this test, make sure to block off a section of the road with safety cones and obey local laws. 1. Park a vehicle in the centre of the field of view of the LPR camera. 2. The vehicle license plate text should be displayed in the image panel as an image overlay. 3. If the license plate does not appear or does not appear correctly, check the following. a. Software is setup correctly. See Software Configuration on page 9. b. The camera is aimed so that the target vehicle is at the correct distance. See Overhead Mounting on page 2 or Roadside Mounting on page 3. c. The license plate is horizontal in the image. See Positioning the LPR Capture Kit on page 8. d. The license plate should be bright compared to the rest of the scene. e. There is contrast between the license plate background and the alphanumerics. 4. Drive a vehicle through the field of view of the LPR camera and check that the license plate was read correctly. 5. Review each frame of the vehicle passing through the field of view. The brightness of the license plate should peak as the vehicle passes the centre of the field of view. 6. Unblock the road and watch the LPR camera capture actual traffic. Run a License Plate Search with a blank search term and wait until at least 100 search results are found. For help on using the search function, see the Avigilon Control Center Client User Guide 7. Playback the video over the search range and see if any license plates were rejected (did not generate a result). Most often license plates are rejected if: The reflective coating is severely worn off. The license plate is from a region with a different font. 10
8. Click through the search results and compare it to the captured image. Incorrect results are often caused by: The license plate is partially covered. The license plate is dirty. 9. Advertisements and other text on vehicles may be interpreted as license plates and generate extra results. 11
Specifications Camera Resolution Single Lane 1280 x 720 Dual Lane 2592 x 720 Illuminator Technology Wavelength High-power SMT LED 850 nm Network Network Cabling Type Connector Security Protocol 100BASE-TX CAT5 RJ-45 SSL UDP, TCP, SOAP, DHCP, Zeroconf Mechanical Enclosure Dimensions(LxWxH) 284 mm x 279 mm x 221 mm (11.0 x 11.2 x 8.7 ) Weight 4.0 kg (8.8 lbs) Mount 4x M5 holes at 40mm x 62mm (1.57 x 2.44 ) Illuminator Power Supply Dimensions (LxWxH) 160 x 160 x 81 mm (6.3 x 6.3 x 3.2 ) Weight 1.85 kg (4.1 lbs) Mount 4 x M4 holes at 145 mm x 123 mm (5.71 x 4.85 ) Electrical Camera Power Source Power Consumption Power Connector Illuminator Power Source Power Consumption Power Connector 24 VDC, 24 VAC, PoE: IEEE802.3af Class 3 compliant 6 W per camera 2-pin terminal block 24 VDC, 24 VAC 72 W 3-wire terminal block, 12-20 AWG Environmental Environmental Rating Operating Temperature Storage Temperature IP66-10 C to +45 C (14 F to 113 F) -10 C to +70 C (14 F to 158 F) Certification UL 60950 CSA60950 EN 60950-1 CE ROHS WEEE 12
Outline Dimensions Figure I: LPR Enclosure A B [4.7] 120 [3.4] 86 = 30 [.4] [1.6] 10 40 [.4] 10 65 5 = A [1.6] 40 [3.1] 80 [.4] 10 [7] 180 [8] 204 A - A 75 [3] = 62 = [2.4] B [.24] Ø 6 INCHES MM Figure J: Enclosure Wall Mount 13
Appendix of Images The following images provide a reference when installing an LPR camera. Figure K: Recommended Overhead Mounting Location Figure L: Figure 10 License Plate Illuminated at Night 14
Figure M: Roadside View at Max Offset Figure N: Enclosure Wall Mount 15