| 摘要 |
<p>A three-dimensional density distribution of a log is reduced to a two-dimensional structure (205) that provides a convenient image or visualization of defects like knots (210) or voids (240) in a log, to facilitate grading and/or optimization of a sawing strategy for the log. The two-dimensional data structure is based on cylindrical or modified cylindrical coordinates Z and υ. To provide a more compact identification of defects, modified cylindrical coordinates use a Z-axis that follows the growth center (125) in the log and determines data points by evaluating properties of the log along rays at an upward angle (ζ) corresponding to limbs in a tree. A process for identifying the growth center at any distance Z along the length of the log examines or accumulates the gradient of density along lines through a cross-section of the log. Manual grading and sawing optimization can employ viewing of an image based on the two-dimensional data structure with superimposed marks indicating the boundaries of faces cut from the log. Automated grading and sawing optimization employs the two-dimensional data structure to reduce processing time when compared to processes that manipulate three-dimensional data structure.</p> |
