The master’s thesis explored photogrammetry as a potential method for calculation of roundwood volume. The data was acquired from field images of stacks which were marked with four control points. A total of 37 stacks divided into three diameter classes were recorded. Prior to recording, the logs in the stacks were manually measured and numbered. Log length was 8.25 m. Volume was calculated using Newton’s formula. The recorded images were processed with Pix4D, CloudCompare, ArcMap and Microsoft Excel software. Pix4D was used to create a point cloud from the acquired images. After measuring the exact distance between control points, we translated the point cloud into the metric system. The other software was used to calculate the volume of the point cloud representing stacks. We discovered that the correlation between the actual volume of wood in the stack and the volume of the raster model is best described with the power function. Forecast volume deviated from actual volume by -2,5 m3 to 1,5 m3. The average error rate of our model is 5.7% (RMSE).
|