Photon Focus MV1-D2048-3D06 series, User Manual

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5.2 3D Features
5.2.4 Interpolation Technique
Structured light based systems crucially rely on an accurate determination of the peak position
of the Gaussian shaped laser line. The LineFinder algorithm in the MV1-D2048-3D06 cameras
applies nonlinear interpolation techniques, where 16 data points are calculated between two
pixels within the Gaussian shaped laser line. This technique is superior to other commonly used
detection techniques, such as the detection of peak pixel intensity across the laser line
(resulting in pixel accuracy) or the thresholding of the Gaussian and calculation of the average
(resulting in sub pixel accuracy).
The nonlinear interpolation technique used in the LineFinder algorithm results in a better
estimate of the maximum intensity of the laser line. The data mapping for the 3D data block is
shown in Section 5.2.6 and the basics of the interpolation principle are illustrated in Fig. 5.6.
The line position (PEAK) is split into a coarse position and a fine position (sub-pixel). The coarse
position is based on the pixel pitch and is transferred in PEAK [15:4]. The sub-pixel position that
was calculated from the LineFinder algorithm is mapped to PEAK [3:0] (see also Section 5.2.6).
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