Abstract:The visual odometer technology was used to restore the posture of the continuous photographic sequences. The sampleplot survey system was constructed based on the images of the restored posture. The system can estimate the position and DBH of the sample trees in the sampleplot by recovering the image posture scale, defining the plot coordinate system, and sample tree marking. Totally 12 circular sample plots with radius of 7.5m were continuously photographed to obtain the image sequence. And then the obtained image sequence was processed with the constructed sample plot survey system to measure the position and DBH of the sample trees. The results showed that the deviations of estimated values of sample tree position of the plots in the xaxis and yaxis directions were 0.04m and -0.03m, respectively, and the root mean square error (RMSE) was 0.21m and 0.17m, respectively. The BIAS and RMSE of the estimated DBH were 0.09cm (0.51%) and 0.88cm (5.03%), respectively. The results showed that the visual odometer technology had a great potential to restore the image posture and to use the nonpoint cloud method to estimate the tree position and the breast diameter from the picture by plot survey method.