JAI TS(C)-4032EN Digital Camera User Manual


 
EN Camera Series
46 Camera Features
Note: Gain Value is Gain entry in camera LUT after calibration.
When the EN camera is controlled by a light sensor, user can monitor the gain value in the EN setup
software by accessing "Camera Gain" status register (Address = 232). This Gain value is the Gain
Table Entry in LUT after calibration (left side of the table above).
6.3.4 HDR Mode (4032EN Only)
By enabling HDR mode, the dynamic range increases by 12dB (x4). In other words, the camera can
include the meaningful grayscale information up to 4 times normal linear saturation level.
You can consider enabling this feature, if your application needs to avoid unexpected over-exposure
caused by reflection of sunlight, structural shadows, or large variations of plate reflections.
Normally, once the plate is over-exposed, there is no information to be extracted for post
processing such as LPR or matcher. HDR mode prevents the image from saturating too fast, while
maintaining the sensitivity in a dark area. Therefore, you can always capture readable plate images
regardless of severe abnormal conditions.
In the example above, Pixel P1 and P2 (dark pixels) continue integration without reset. Pixel P3 and
P4 (bright pixels) are reset and continue the integration from the dual-slope reset voltage.
Therefore, the saturation speed of the bright pixels can be slowed down, while maintaining detail
information in the dark area.
By using the light sensor, the camera automatically estimates the sensor saturation voltage, optimal
exposure time and gain. Then, the camera automatically adjusts the dual-slope reset voltage and
reset timing dynamically, in order to include an extra 12dB (x4) dynamic range. This process is fully-
automated to achieve a total 139dB system dynamic range.