8. Capturing Images 87
Warning
The reference image for evaluating the PRNU correction must not contain sat-
urated pixels. This may introduce artifacts due to an incorrect evaluation of
calibration parameters.
The camera evaluates the reference compensation level within the current LMR, possibly smaller than
the current ROI; this allows optimizing the algorithm according to a portion of the scanned image only.
The PRNU correction algorithm allows also to bring the average level of the compensated image to a
given target reference level (target gray level).
Note
The target gray level algorithm uses the Digital Gain control to achieve the
required brightness level; when implementing the target gray level and saving
the FPN conguration, you must care saving camera parameters according to
Section 8.11. Using color NECTA models, White Balance control values will
be saved to preserve the correct white compensation parameters.
MaestroUSB3 viewer and application examples show in detail the use of the PRNU compensation and
allow you to experience the target grey level algorithm.
8.2.3 Restoring NECTA calibration
After calibration, you can save the result directly in a NECTA internal memory, so you can reload the
calibration parameters when necessary. When powered on, NECTA does not preload any calibration;
the user can either load one of stored in the internal camera memory during the setup or evaluate a new
FPN correction.
Note
If calibration is saved using the deprecated method
device.Calibration.Save(), relevant control values (Digital Gain,
White Balance, Shutter etc.) must be saved and restored using methods
described in Section 8.11.
If a calibration has been loaded from memory and needs to be cleared (e.g. choosing Mode 1 instead of
Mode 0), user can recall an empty calibration:
To Next Page
Loading...