Software User Manual - Argos 3D-P320
Last change: 2 February 2016
Version 0.14
© Bluetechnix 2016
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The frame rate of the data interface will be divided by the number of configured frames to be averaged, e.g.,
if the camera is configured to 40 frames per second, and the frame average filter with number 4 is used, the
resulting output frame rate will be 10.
Note that the Frame Average filter on amplitude data cannot be enabled unless the Frame Average filter on
distance data is also enabled.
4.4
ToF Image Enhancements
4.4.1
Pixel invalidation
The Argos 3D-P320 provides an on-board check for invalid pixels:
Underexposed pixels: The amplitude is too low for the distance value to be trustworthy. The Argos
3D-P320 sets the pixel distance to the maximum value. The threshold is set via register
ConfidenceThresLow
.
Overexposed pixels: The amplitude is too high for the distance value to be trustworthy. The Argos
3D-P320 sets the pixel distance to the minimum value. The threshold is set via register
ConfidenceThresHigh
.
Invalid pixels: The Argos 3D-P320 features an additional amplitude check called ACF (auto
correlation function) Plausibility Check. It detects inconsistent pixels e.g. in case of fast movement in
the scene.
4.4.1.1
Distance values
If the amplitude of the reflected signal is below a threshold (underexposure) the distance value of the
appropriate pixel will be set to 0xFFFF. If the amplitude is too high (overexposure) the distance value will be
set to 0x0000.
For invalid pixels, the distance value is set to 0x0001.
4.4.1.2
XYZ values
If the amplitude of the reflected signal is below a threshold (underexposure) the X value of the appropriate
pixel is set to 32767 (0x7FFF), i.e., the largest positive Int16 value. Y and Z values are set to 0.
If the amplitude of the reflected signal is above a threshold (overexposure) the X of the appropriate pixel is
set to 0. Y and Z values are set to 0 as well.
If the ACF plausibility check classified the pixel’s distance as invalid, the X value of the appropriate pixel is
set to 1. Y and Z values are set to 0.
4.4.2
Temperature compensation
The camera firmware continuously monitors temperatures of LIMs, TIM, and base board, and corrects the
measured distance with cubic polynomials.
