# Comparison of Bone Segmentation Software over Different Anatomical Parts
## 3 Results  
The software features considered in the present analysis are those reported in Table 2.  
Additional features were analyzed, but because these were found to be available exactly in each package, these are not reported in Table 2 but rather listed here below: unlimited number of image slices; multiplanar visualization and representation; correspondence amongst the coronal, axial, and sagittal orientations; crop and zoom; contrast and brightness adjustments; separation of the regions of interest; linear, angular, and volumetric measures; simultaneous planar images and 3D rendering; export of images and mesh data; export in STL file format. The computational import time of the DICOM files was found to be within the range of 1-6 s considering all analyzed software packages. The longer \"time-to-import\" found for the Segment 3D Print software (3.7 \(\pm\) 1.1 s) is likely due to the simultaneous creation of 3D volume rendering during the uploading process. Marked differences were observed in the time to create the model, this ranging from 2.1 \(\pm\) 0.4 s in Amira to 23.9 \(\pm\) 13.3 s in Segment 3D Print, on average. Operability was satisfactory for each of the five software packages; these were efficient enough to obtain final results for all 15 anatomical models in a few hours (Figure 2). By keeping their own default settings in each of the five software packages, Mimics showed the smallest final number of triangles on average over the 15 models, i.e., around half that of the other software packages, which resulted eventually in the smallest and most consistent file size in terms of standard deviation (Table 2). At the end, a very similar ratio of triangles per MByte was observed, approximately 20 thousand, apart from Mimics, \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **Mimics** & **Anira** & **D2P** & **Simpleware** & **Segment 3D Print** \\  & **(\(\pm\)24.0)** & **(\(\pm\) 2019.4)** & **(\(\pm\) 1.0.2.055)** & **(\(\pm\) 2021.06)** & **(\(\pm\)3.3 R 9056)** \\ \hline \multirow{2}{*}{**Time to import [s]**} & \(1.4\pm 0.5\) & \(2.4\pm 1.5\) & \(2.1\pm 0.3\) & \(2.5\pm 0.7\) & \(3.7\pm 1.1\) \\  & \((1\)–\(2)\) & \((1\)–\(5)\) & \((2\)–\(3)\) & \((1\)–\(4)\) & \((2\)–\(6)\) \\ \hline \multirow{2}{*}{**Time to create the model [s]**} & \(5.8\pm 3.9\) & \(2.1\pm 0.4\) & \(11.1\pm 4.3\) & \(5.2\pm 2.4\) & \(23.9\pm 13.3\) \\  & \((2\)–\(14)\) & \((2\)–\(3)\) & \((4\)–\(19)\) & \((3\)–\(10)\) & \((9\)–\(55)\) \\ \hline \multirow{2}{*}{**Number of triangles**} & 849,995 \(\pm\) 633,670 & 1,782,831.6 \(\pm\) 1,145,476 & 1,752,240 \(\pm\) 1,120,912 & 1,796,269 \(\pm\) 1,132,502 & 1,816,860 \(\pm\) 1,107,694 \\  & \((203,616\)–\(2.219,446)\) & \((332,574\)–\(3,843,000)\) & \((526,460\)–\(3,764,380)\) & \((568,436\)–\(3,834,908)\) & \((576,532\)–\(4,200,338)\) \\ \hline \multirow{2}{*}{**File size [ megabytes]**} & 76.0 \(\pm\) 48.8 & \(84.8\pm 54.5\) & \(83.4\pm 53.3\) & \(85.5\pm 53.9\) & \(86.5\pm 52.7\) \\  & \((23.9\)–\(163)\) & \((25.3\)–\(183)\) & \((25.1\)–\(179)\) & \((27.1\)–\(182)\) & \((27.4\)–\(200)\) \\ \hline \multirow{2}{*}{**Number of triangles per MBByte**} & 10,433.4 \(\pm\) 2111.5 & 21,019.2 \(\pm\) 51.2 & 21,004.8 \(\pm\) 32.0 & 21,003.1 \(\pm\) 48.2 & 21,005.5 \(\pm\) 31.1 \\  & \((6650\)–\(13616)\) & \((20,973\)–\(21,165)\) & \((20,971\)–\(21,077)\) & \((20,889\)–\(21,088)\) & \((20,972\)–\(21,079)\) \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Main features of the five software packages analyzed. The results are means \(\pm\) standard deviation over the fifteen models analyzed (five anatomical areas, each from three subjects), along with range values (min-max). For the sake of comparison, the table format is similar to that reported in the previous work [25] (with the exception of information related to basic two-dimensional and 3D features, which is not reported here). where this value was halved.