Pseudo-Four-Phase-Shift Algorithm for Performance Enhancement of 3D-TOF Vision Systems

Real-Time Processing of 3D-TOF Data in Machine Vision Applications

“…7 -Fig. 10 illustrate the influence of the calibration method and the motion artefact compensation algorithm proposed in (Hussmann et al, 2011a) on the distance image using the state-of-the-art 4-phase shift algorithm and the pseudo 4-phase shift algorithm proposed in (Hussmann & Edeler, 2010) respectively. Fig.…”

“…A measure object (10 cm x 10 cm x 12 cm) is placed on a conveyor belt, which runs at a speed of 1 m / s. A PMD TOF camera (PMD[vision]® CamCube 2.0) with 204 x 204 pixels is placed 103 cm above the conveyor belt. The raw data (U a and U b ) of the PMD camera for the four different phases  ( = 0°,  = 90°,  = 180° and  = 270°) are captured and the proposed motion compensation algorithm in (Hussmann et al, 2011a) combined with the pseudo-four-phase-shift algorithm proposed in (Hussmann & Edeler, 2010) is investigated offline using Matlab. …”

“…The pseudo 4-phase shift algorithm increases this frame rate to 100 Hz and hence is well suited for real-time machine vision applications. A more detailed description of the pseudo 4-phase shift algorithm can be found in (Hussmann & Edeler, 2010).…”

“…10 has been calculated and the results are shown in table 2. It can be clearly seen that the proposed motion compensation algorithm (with calibration) in (Hussmann et al, 2011a) combined with the pseudo-four-phase-shift algorithm proposed in (Hussmann & Edeler, 2010) has almost the same standard deviation for the background (area 4) and the object (area 2) as the state-of-the-art 4-phase shift algorithm and the motion compensation algorithm (with calibration) in (Hussmann et al, 2011a). However the mean value of the proposed motion compensation algorithm (with calibration) has an offset due to the calibration.…”

“…In (Hussmann & Edeler, 2010) we presented a pseudo-four-phase-shift algorithm for 3D-TOF photonic mixer device (PMD) cameras, which only has to capture two phase images and thereby doubles the frame rate. Hence distance uncertainties by fast moving objects will be reduced.…”