Police Computer Systems

1. Police Computer Systems By: Daniel Carbone Derek Martinez Darius Jones Bahiru Balicha

2. Project54 Introduction • The current Mobile Digital Video System is a part of Project 54. • Project 54 system combines police vehicle equipment into an internal network. • The system is powered by an embedded computer that deals with all the internal data, provides control to the system via manual and voice interface, and coordinates remote access to the vehicle resources.

3. Goals • Increase the quality and capacity for mobile video recording systems by recording evidence in digital video formats on high capacity digital storage media • Introduce more interaction with the environment to extend the Mobile Video System (MVS) functionality • Create a versatile easy-to-navigate video database allowing the tagging and embedding of related information • Provide wireless remote access capability

4. Digital Video Recorder (DVR-54) • PC based. Running Windows (or Linux). • Several Software and/or Hardware video encoding engines. • “Hot-swap” high volume HDD. • TCP/IP network connection • Serial port for connection to the IDB bus.

5. MPEG2 format • MPEG is a set of standards for digital video and audio signal compression. • Based upon a number of compression techniques • The main compression technique is based on the Discrete Cosine Transform (DCT) • The standard defines how the DCT and subsequent quantization process is used to reduce the data rate and the way video and audio data packets are multiplexed together to form the compressed data stream.

6. MPEG2 • The DCT compression technique leverages the fact that adjacent pixels in a picture are usually strongly correlated being close to a common shared value • The DCT operates on a local area of 64 pixels organized into blocks of 8 x 8 pixels. • The DCT transforms mathematically the image data in a way that tends to group the common digital signal elements in the block together. • The DCT concentrates the energy into the first few coefficients corresponding to low spatial frequency variation. Many of the higher frequency coefficients are often close to zero due to the fact that a strong correlation often exists between pixels in a small local neighborhood

7. MPEG4 format • A fairly new format. 1-2 years on the market. Still “in development” • MPEG4 allows the creation of videos with very high visual quality and relatively low file sizes • One of the most popular MPEG4 CODEC is DivX. (http://www.divx.com)

8. CODEC comparison Test system - CPU — AMD Athlon™ XP 1500+; RAM — 128 Mb

9. Data storage • Today’s technology provides large capacity hard disks at a reasonable cost. These disks can hold more high quality video than any VCR video tape on the market. It is a very convenient and cost effective solution. Headquarters Video Storage Cruiser Video Storage Video files are stored to an 40-60-80-120 Gb “hot swap” hard drive, which is detached when desired and/or full. Full Hard Drive Empty Hard Drive

10. Routing Video Signals Using a Video Switch introduces flexibility in recording evidence from different camera views Control data To Embedded PC for monitoring Mobile Wireless Camera Video Switch To PC DVR Front View Camera MPEG-2 CODEC Rear View Camera Video capture card

11. Recording Scenarios • Patrol Mode Video is recorded from the Front View camera using the medium quality video engine • Alarm Mode Front view camera > high quality video engine Rear view camera > medium quality video engine Mobile camera can be switched manually by police officer

12. Interacting with environment The Video System is designed to be “smart” and will be able to “decide” automatically in what mode to record and when to switch between them These decisions are based on information about the current situation. For instance if the light bar is switched on then the video system switches to the Alarm Mode This information is acquired by observing the internal data bus (IDB Bus) messages

13. IDB bus and event processor The IDB bus is an information channel for messaging between the main computer and peripheral devices such as lights, siren, video system itself and other devices. By “listening” to the data traffic on the IDB bus and catching “important” events using an event processor, the video system knows what is happening around it. For instance, if the main PC sends a command for the siren to turn on, the video system knows it is a sign of emergency and performs appropriately.

14. Archiving Video • The Video Database has to be a synchronized set of video files and related text information. Non video information, such as GPS, radar readings, time/date, and notes must be correlated to the video data. • An easy way of database navigation must be provided (i.e., it is not an easy task to find a short fragment among tens of hours of video)

15. Video Database Structure Timeline MPEG4 video files HDD MPEG2 video files Siren Active Siren Active Siren Active Notes-> Notes-> entries in *.log file GPS,Radar-> GPS,Radar-> Emergency marks such us “Siren Active” are introduced for search purposes: with them it is easier to locate an “important” video fragment

16. THE ACCIDENT Routine recoding This file isn’t important Emergency recording Siren Active There is always a delay between an accident and the reaction to it “Endless Recording” feature • This feature introduces an optimization in evidence recording. • Since video recording is conducted continuously, a lot of disk space is wasted on “recording traffic flow”. • Video files that do not contain any evidence can be deleted, and a significant amount of disk space can be recovered.

17. Remote Access Feature It is assumed that the police cruiser will have a data link to main control office. Let us call it the “Dispatcher”. Such a Dispatcher allows us to implement some additional features that will make the Video System more accessible, more autonomous, and from some point of view, more “intelligent”.

18. Remote Access Features • Remote Access to Video Database • Navigate the Database • Download Evidence • Obtain relevant system information (e.g., free space on the media) • Remote Troubleshooting • The system can send SMTP (e-mail) messages to the Dispatcher regarding technical problems related to the video system in the car. • A technician can then log into the system using Telnet and attempt to fix the problem remotely

19. Navigating the Video Database • The Dynamically generated web page reflects current DVR-54 information.

20. Downloading Video • It is desirable to allow access from the cruiser remotely in cases of emergency. • The major constraint in using this feature is low speed data link (9600 bps is often a maximum) • There are several ways to decrease the size of visual information to transmit: • Cut a small piece of video from a big file. Leave only important scenes for transmission. • Make snapshots from video files. • Make a slideshow. It is more informative than a snapshot but smaller than continuous video.

21. IDB Video Switch IDB controller Virtual VCR The MVS Prototype:

22. Video Switch Design IDB Bus User Input User output OUT3 IN3 Wireless cam. DVR-54 MPEG4. OUT2 IN2 Rear cam. DVR-54 MPEG2 OUT1 IN1 Front cam. Monitor IN0 OUT0

23. Power Supply Circuitry -5V +5V Video Switch Circuitry IDB Board Circuitry Video Switch Design

24. Video Switch Circuitry to PIC controller + 5V - 5V GND

25. + 13.8V + 13.8V + 5V - 5V GND Power Circuitry • Voltage • inverter • -5V • 40 mA • Voltage • regulator • 5V • 80 mA Total current consumption is 120 mA

26. Video Switch Design Features • There have been reported issues regarding the use of IDB boards and the quality of police radio reception which have been traced to EMI. • The following actions were taken to reduce EM noise from the video switch board : • Ground planes cover top and bottom sides of the board • Shielded components are used where necessary

27. Video Switch Advantage • The IDB Video Switch was not designed exclusively for the DVR-54. • The IDB Video Switch makes it possible to upgrade the current Project 54 system with multiple cameras using existing in vehicle video equipment • Demonstration: ID Control video recorder with multiple camera set.

28. Embedded platform for DVR-54 - CPU: AMD Athlon™ XP 1500+; - RAM: 128 Mb - Case: Aluminum chassis 200(w) x 181(h) x 280(d) mm - TV-Out and S-Video Out PCI Slot x 2; USB port x 4: IEEE1394 port x2 Serial Ports: COM1 COM2 10/100Mb Fast Ethernet LAN

29. Dvr.java DVR-54 Software Design dataLogger.java Log file Playlist file commandParser.java Video Data Base DVRsharedVariables.java Virtual VCR encode.exe IDBport.javaEvent processor AVIrecorder.java MPEGrecorder.java WebServer.java Video Capture Card MPEG2 hardware encoder TCP/IP connection IDB controller Video Switch To cameras IDB Bus

30. Remote Access

31. Video Picture Area Control Buttons Volume Progress/navigation slider Brightness Video File Description field Playback on Embedded PC

32. Playback on Embedded PC

33. Other features (continue) Monitoring T.A.W MobileDigi-View Scout Cam Digital Eyewitness Project 54 + DVR-54 In order to decrease the cost even more the Embedded PC and the DVR-54 can be integrated into a single unit

34. Other features (continue) • Remote audio transmitter. • This optional feature is used by many mobile video systems. The DVR-54 has audio inputs that can be connected to several audio sources like internal MIC or Wireless receiver. • Triggering events for starting recording may include: • light bar activation event, • brake activation, • airbag release, etc. Triggers that do not have “access” to the IDB bus may obtain one in following way It is similar to “push-to-talk” button implementation TTL in IDB Bus IDB box brake activation switch TTL in • airbag release switch

35. Conclusion • This system has huge potential, but is still in developmental stages. • Cost is unknown as of yet, but the system will most likely be ready for use by late 2004/early 2005. • Thanks to the University of New Hampshire for most of the information contained in this presentation.