The invention provides a stumpage breast height
diameter measuring method based on an
optics similar triangle method. The stumpage breast height
diameter measuring method based on the
optics similar triangle method relates to forest measurement and includes the following steps: a camera and a
laser are used to create a stumpage breast height
diameter measuring
system; the camera is used to take photos of a to-be-tested stumpage to obtain images of the stumpage; and after the shot images of the stumpage are preprocessed, a point, namely a
laser spots falling on a
phase plane, (X', Y') is obtained. According to an
optics similar triangle principle, the point (X', Y' ) that the
laser spot falls on the
phase plane carries out coordinate transformation towards a three-dimensional space to obtain a point (X, Y, Z). The point (X, Y, Z) projects towards a horizontal direction to obtain a point (X projection, Y projection) after being processed. A least square
circle fitting method is adopted to carry out
circle fitting on the point(X projection, Y projection), and then a round
radius parameter after fitting is a breast height diameter of the to-be-tested stumpage. The stumpage breast height diameter measuring method based on the optics similar triangle method has the advantages that
algorithm can be realized easily and can measure the stumpage breast height diameter quickly in non-
contact mode.