Figure 3From: Calibration of an orientation sensor for freehand 3D ultrasound and its use in a hybrid acquisition system Reconstruction drift. The sensorless reconstruction paradigm assumes that the correlation between two patches of data depends only on the separation between them. However, various other effects can bias the correlation value. This results in biased inter-frame offsets and a consequential drift error in the reconstructed sequence. Here, the dashed lines show the correct frame positions and the solid lines show the drifted reconstruction.Back to article page