# Subtitling 3D VR Content with Limited 6 DoF: Presentation Modes and Guiding Methods
## 5 Discussion  
This study aimed to provide insights into the accessibility of immersive media, by focusing on 3D VR content subtitling. As a response to the increased relevance of this content format and _medium_, in conjunction with its lack of accessibility solutions, two key research questions in this topic were explored: the appropriateness of different presentation modes and the potential benefits of using guiding methods. As with recent studies on VR360 video subtitling [9], the results from the conducted user tests showed that an _Always-visible_ presentation mode is significantly more appropriate than a _Fixed-positioned_ presentation mode for subtitles. The differences are even larger \begin{table}
\begin{tabular}{l c c c c c} \hline \hline
**Question Items/Answers** & **Totally Agree** & **Partially Agree** & **Neutral** & **Partially Disagree** & **Totally Disagree** \\ \hline The availability of indicators (arrow) is beneficial for a better positioning within the VR environment & 7 (29.2\%) & 8 (33.3\%) & 5 (20.8\%) & 4 (16.7\%) & - \\ \hline The availability of indicators (arrow) is beneficial for a better identification of the active speaker when using _Always-visible_ subtitles & 9 (37.5\%) & 9 (37.5\%) & 4 (16.7\%) & 2 (8.3\%) & - \\ \hline The availability of indicators (arrow) is beneficial for a better identification of the active speaker when using _Always-visible_ subtitles & 6 (25\%) & 7 (29.2\%) & 7 (29.2\%) & 3 (12.5\%) & 1 (4.2\%) \\ _Conic-style_ subtitles & 6 (25\%) & 8 (33.3\%) & 6 (25\%) & 4 (16.7\%) & - \\ \hline The inclusion of indicators (arrow) can have a negative impact on immersion while watching VR content & - & 1 (4.2\%) & 3 (12.5\%) & 8 (33.3\%) & 12 (50\%) \\ \hline The inclusion of indicators (arrow) can have a positive impact on immersion while watching VR content & 6 (25\%) & 7 (29.2\%) & 5 (20.8\%) & 4 (16.7\%) & 2 (8.3\%) \\ \hline The provided indicator (arrow) is visually attractive & 6 (25\%) & 8 (33.3\%) & 5 (20.8\%) & 5 (20.8\%) & - \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Benefits and appropriateness of guiding methods (3D arrow). \begin{table}
\begin{tabular}{l c c c c c} \hline \hline
**Question Items/Answers** & **Totally Agree** & **Partially Agree** & **Neutral** & **Partially Disagree** & **Totally Disagree** \\ \hline Subtitles can contribute to a better content comprehension for hearing users & 14 (58.3\%) & 8 (33.3\%) & 2 (8.3\%) & - & - \\ In general, I believe that VR subtitling is a relevant feature & 15 (62.5\%) & 7 (29.2\%) & 2 (8.3\%) & - & - \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Relevance of (3D VR) Subtitling. in 3D VR environments than in VR360 video environments, particularly due to two key factors: depth and 6 DoF (i.e., freedom to explore). Unlike in VR360 video environments in which subtitles can, for example, be replicated each 120\({}^{\circ}\) in the sphere (which is the strategy proposed and adopted by BBC, among others [9; 13]), this is clearly not an appropriate and sufficient solution in 3D VR environments, because of potential content blocking and the depth dimension, respectively. The conducted user tests provided relevant insights into these relevant issues. In addition, a novel _Comic-style_ presentation mode was proposed and very well received by users. This mode was shown to provide similar levels of presence as the _Always-visible_ mode, for all scales of the IPQ questionnaire (Tables 3-6 and Figure 4), with the exception of the Experienced Realism scale. This may be because the addition of comic-like bubbles has an impact on the experienced realism, because the story resembles a comic or animation film. The _Comic-style_ was, in general, the second most preferred mode by users, but the most preferred mode in terms of relevant aspects, such as speaker identification and integration with the VR content.