Thermal and Optical Cameras. By Philip Smerkovitz TeleEye South Africa

Transcription

1 Thermal and Optical Cameras By Philip Smerkovitz TeleEye South Africa

2 OPTICAL CAMERAS OVERVIEW Traditional CCTV Camera s (IP and Analog, many form factors). Colour and Black and White Images. Uses CCD or CMOS Senor technology Wide Application Security and Surveillance Management ANPR Facial Recognition Wide range of resolutions (700TVL, D1, 1080p HD, 4K, Megapixel).

3 HOW LIGHT WORKS OPTICAL CAMERAS Light is an electromagnetic radiation. The human eye is sensitive to this radiation and various radiation frequencies (colours). Visible light occupies a very small range. (400nm -700nm) Optical CCTV is concerned with visible light.

4 HOW OPTICAL CCTV WORKS Visible light enters via lens. Lens focuses the image onto an electronic CCD or CMOS sensor. Camera electronics process the sensor chip information and produces video signal. Video signal can be RAW or compressed signal.

5 FACTORS AFFECTING CAMERA SENSITIVITY LENSES Lens Aperture Lenses allow only a small percentage of light to reach the camera s sensor. Further effected by the aperture of the lens. F1.0 lens allows 20%, an F1.4 allows 10% and F2.0 only allows 5% of lights passed. Smaller F Rating = Higher Cost and Performance Lens Quality Lens quality determines efficiency of the light transmitted through the lens. Aspherical produces higher quality than standard lenses. Glass lenses produce higher quality than standard lenses.

6 FACTORS AFFECTING CAMERA SENSITIVITY SENSOR The camera sensor is the soul of the camera and is key to determining the low-light characteristics. It is a solid-state device that captures light and converts what is sees into an image. The sensor is the electronic equivalent of film. Sensor type and size determine light handling.

7 THE EVOLUTION OF IMAGE SIZES Important Advantages and Disadvantages A single camera can replace multiple cameras Multiple zoom within picture High resolution = Higher cost per camera and infrastructure (local & remote) The more pixels, the more light required Specify according to application ANPR, Facial Recognition, Perimeter Protection, Remote Offsite Monitoring

8 LIGHT SOURCES WHITE LIGHT IR ILLUMINATION Optical CCTV requires light to work - Without light there is no image. Without the right light there is no good image. Not all light is the same Quantity, Quality, Distribution. Visible White Light and Infra-Red Illumination are common sources.

9 LIGHT SOURCES WHITE LIGHT White light is visible to the human eye White light can provide for colour CCTV images at night White light provides for additional safety as a deterrent and enhances security The angle of the light source must match the camera FOV Drawbacks are light pollution, power, colour temperature and maintenance

10 LIGHT SOURCES IR ILLUMINATION Infra-Red light uses LED illumination Infra-Red light is invisible to the human eye No light pollution Provides a targeted beam pattern Commonly integrated into outdoor and indoor cameras

11 DETECTION, OBSERVATION, RECOGNITION, IDENTIFICATION Very important factor when specifying the function of a camera Detection Subject occupies 10% of the height of the image scene Observation Subject/s occupy 25% of the height of the image scene Recognition Subject occupies 50% of the height of the image scene Identification Subject occupies 100% of the height of the image scene

12 HOW LIGHT WORKS THERMAL IMAGING Infrared radiation lies between the visible and microwave portions of the electromagnetic spectrum. The primary source of infrared radiation is heat or thermal radiation. Any object that has a temperature above absolute zero emits radiation in the infrared region. The heat that we feel is all infrared. The warmer the object, the more infrared radiation it emits.

13 HOW THERMAL CCTV WORKS Infrared energy coming from an object is focused by the optics onto an infrared detector Macrobolometer. The detector sends the information to sensor electronics for image processing. The electronics translate the data coming from the detector into an image. The image can be viewed on a standard video monitor or LCD screen and integrated into CCTV.

14 THE THERMAL IMAGING CAMERA Drop-in replacement (or compatible addition) to existing CCTV security camera. Capable of imaging in a total absence of light (0 lux) using infrared thermal energy. High contrast imagery from fixed mount or pan/tilt cameras.

15 WHAT THERMAL CAMERAS SEE

16 WHY USE THERMAL IMAGING? When artificial illumination at night is not economical or is undesirable. Wide-area surveillance in critical infrastructure or high-value installations where lighting is unwelcome or impractical. Covering long distances where it is impractical or not cost effective to deploy optical cameras Difficulties with ordinary cameras during daylight.

17 WHY USE THERMAL IMAGING? Provides high-contrast imagery, improves reliability of video analytics (intelligent video). Penetrates better than visible cameras through most types of haze, dust, and other obscurants.

18 BENEFITS & VALUE of THERMAL CAMERAS Total Darkness Through Smoke Through Fog

19 BENEFITS & VALUE of THERMAL CAMERAS

20 BENEFITS & VALUE of THERMAL CAMERAS Recently Driven Vehicle Visible Image Thermal Image

21 BENEFITS & VALUE of THERMAL CAMERAS Firearm Hidden in Shrubs Visible Image Infrared Image

22 BENEFITS & VALUE of THERMAL CAMERAS See Through Haze Visible Image SWIR Image

23 BENEFITS & VALUE of THERMAL CAMERAS Thermal Cameras are the best Solution for Outdoor Video Analytic. Ignore stray headlights and reflected light. Eliminate the expense, power and difficulty of lighting large outdoor perimeters.

24 BENEFITS & VALUE of THERMAL CAMERAS Thermal Cameras are an excellent solution for indoor Video Analytics when compared to optical cameras which experience colour changes

25 FEATURES TO LOOK OUT FOR Resolution Comparison 320 x x 480

26 FEATURES TO LOOK OUT FOR DDE Digital Detail Enhancement

27 FEATURES TO LOOK OUT FOR DDE Digital Detail Enhancement Without DDE With DDE

28 FEATURES TO LOOK OUT FOR WDR with Thermal Camera Without WDR With WDR Clearly Displays Foreground & Background Detail. Automatically Optimized Video. Improves Performance of Video Analytics.

29 FEATURES TO LOOK OUT FOR Solar Immunity Sunrise

30 FEATURES TO LOOK OUT FOR CRISP FILTER

31 FEATURES TO LOOK OUT FOR CRISP FILTER

32 DRI Detection Recognition Identification

33 DRI Detection Recognition Identification

34 THANK YOU