The invention relates to computer-implemented method for the 3D reconstruction of a ground surface area by stereophotogrammetry, comprising the steps of: determining corrected Rational Polynomial Camera, RPC, models by performing bundle adjustment (BA) of original RPC models each provided with an image of a set of images of the ground surface area acquired by a remote imaging sensor and each associated to a corresponding original projection function ({P.sub.m}) from a 3D object space to a 2D image space, wherein determining the corrected RPC models comprises determining corrected projection functions ({P.sub.m.sup.cor}) from the 3D object space to the 2D image space; and determining (PC) a 3D point cloud representative (3DPC) of the ground surface area by triangulation, based on the corrected RPC models, of stereo correspondences within images of the set of images. In accordance with the invention, determining the corrected projection functions comprises determining, for each of the original projection function, a 3D corrective rotation around a remote imaging sensor center to be applied in the 3D space before performing the original projection function.

The invention relates to computer-implemented method for the 3D reconstruction of a ground surface area by stereophotogrammetry, comprising the steps of: determining corrected Rational Polynomial Camera, RPC, models by performing bundle adjustment (BA) of original RPC models each provided with an image of a set of images of the ground surface area acquired by a remote imaging sensor and each associated to a corresponding original projection function ({P.sub.m}) from a 3D object space to a 2D image space, wherein determining the corrected RPC models comprises determining corrected projection functions ({P.sub.m.sup.cor}) from the 3D object space to the 2D image space; and determining (PC) a 3D point cloud representative (3DPC) of the ground surface area by triangulation, based on the corrected RPC models, of stereo correspondences within images of the set of images. In accordance with the invention, determining the corrected projection functions comprises determining, for each of the original projection function, a 3D corrective rotation around a remote imaging sensor center to be applied in the 3D space before performing the original projection function.

A depth measuring method and system applicable to a first binocular camera having a zoom lens is provided. The method includes: obtaining a current depth of a target object (S101); determining a focus with which the current depth is measured as a current focus (S102); determining, according to the preset correspondence between depth ranges and focuses, a current reference focus corresponding to a current reference depth range; wherein, the current reference depth range is a depth range in which the current depth falls (S103); determining whether the current focus is the same as the current reference focus; (S104); if the current focus is the same as the current reference focus, determining the current depth as the target depth of the target object (S105); or if the current focus is not the same as the current reference focus, adjusting the current focus to the current reference focus, measuring a current depth of the target object with the adjusted current focus (S106), and proceeding to the operation (S103) of determining, according to preset correspondence between depth ranges and focuses, a current reference focus corresponding to a current reference depth range. An object in various depth ranges is measured with a varying focus. The accuracy of the depth measurement of the target object is thus improved.

A depth measuring method and system applicable to a first binocular camera having a zoom lens is provided. The method includes: obtaining a current depth of a target object (S101); determining a focus with which the current depth is measured as a current focus (S102); determining, according to the preset correspondence between depth ranges and focuses, a current reference focus corresponding to a current reference depth range; wherein, the current reference depth range is a depth range in which the current depth falls (S103); determining whether the current focus is the same as the current reference focus; (S104); if the current focus is the same as the current reference focus, determining the current depth as the target depth of the target object (S105); or if the current focus is not the same as the current reference focus, adjusting the current focus to the current reference focus, measuring a current depth of the target object with the adjusted current focus (S106), and proceeding to the operation (S103) of determining, according to preset correspondence between depth ranges and focuses, a current reference focus corresponding to a current reference depth range. An object in various depth ranges is measured with a varying focus. The accuracy of the depth measurement of the target object is thus improved.

A surveying system includes a distance measuring unit for performing the distance measurement based on the distance measuring light, an optical axis deflector configured to enable two-dimensionally deflecting the optical axis of the distance measuring light, a projecting direction detecting module for performing the angle measurement of the optical axis of the distance measuring light, and an arithmetic control module performs captures the pole by a scan pattern having a predetermined shape, acquires the point cloud data of at least two positions where the scan pattern crosses the pole, calculates an axis of the pole, calculates a direction vector, performs a linear scan along the direction vector, determines as a measuring point a point where an intersection of the optical axis of the distance measuring light and the direction vector coincides or substantially coincides with a measurement result, and calculates the three-dimensional coordinates of the measuring point.

A surveying system includes a distance measuring unit for performing the distance measurement based on the distance measuring light, an optical axis deflector configured to enable two-dimensionally deflecting the optical axis of the distance measuring light, a projecting direction detecting module for performing the angle measurement of the optical axis of the distance measuring light, and an arithmetic control module performs captures the pole by a scan pattern having a predetermined shape, acquires the point cloud data of at least two positions where the scan pattern crosses the pole, calculates an axis of the pole, calculates a direction vector, performs a linear scan along the direction vector, determines as a measuring point a point where an intersection of the optical axis of the distance measuring light and the direction vector coincides or substantially coincides with a measurement result, and calculates the three-dimensional coordinates of the measuring point.

The present invention provides a method for implementing high-precision orientation and evaluating orientation precision of a large-scale dynamic photogrammetry system, including steps: a) selecting a scale bar, arranging code points at two ends of the scale bar, and performing length measurement on the scale bar; b) evenly dividing a measurement space into multiple regions, sequentially placing the scale bar in each region, and photographing the scale bar by using left and right cameras; d) limiting self-calibration bundle adjustment by using multiple length constraints, adjustment parameters including principal point, principal distance, radial distortion, eccentric distortion, in-plane distortion, exterior orientation parameter and spatial point coordinate; and e) performing traceable evaluation of orientation precision of the photogrammetry system. The present invention can effectively reduce the relative error in length measurement.

The present invention provides a method for implementing high-precision orientation and evaluating orientation precision of a large-scale dynamic photogrammetry system, including steps: a) selecting a scale bar, arranging code points at two ends of the scale bar, and performing length measurement on the scale bar; b) evenly dividing a measurement space into multiple regions, sequentially placing the scale bar in each region, and photographing the scale bar by using left and right cameras; d) limiting self-calibration bundle adjustment by using multiple length constraints, adjustment parameters including principal point, principal distance, radial distortion, eccentric distortion, in-plane distortion, exterior orientation parameter and spatial point coordinate; and e) performing traceable evaluation of orientation precision of the photogrammetry system. The present invention can effectively reduce the relative error in length measurement.