FIELD: data processing.
SUBSTANCE: invention relates to compression of a point cloud and, in particular, to encoding and decoding of geometric data of a point cloud collected by a rotating measuring head. Into a bit stream encoded the data (φcoded,n) of the azimuthal angle, which characterizes the azimuthal angle difference, obtained from the azimuthal angle φ(Pn), taking into account the survey angle for the sensor which has taken the point cloud point, wherein absolute value of data (φcoded,n) of the azimuthal angle is limited by boundary value (B), which depends on characteristics of sensor and coding parameter of azimuthal angle difference. Azimuth angle difference is the difference between the azimuthal angle φ(Pn) and the predicted angle (φpred,n) for the given azimuthal angle, wherein the predicted angle (φpred,n) for the point Pn of the point cloud is calculated based on the angle φ(Pal) of the already encoded point Pal by shifting it by a value which is a multiple of the elementary azimuthal shift Δφ.
EFFECT: high efficiency of encoding geometric data of a point cloud.
12 cl, 14 dwg
