# GazeGuide: An Eye-Gaze-Guided Active Immersive UAV Camera
## 5 Results and Discussion
### Experiment 2  
This experiment was aimed to measure the focus precision (accuracy) and change in viewpoint for the specified proposed GazeGuide and RC methods. **Accuracy:** For the effective focus precision analysis of the experiment, unique ArUco markers were attached to the ToIs. These moving markers (highlighted in red in Figure 6) specified the position  
Figure 8: Mean time-to-complete Experiment 1 with: (**a**) variation 1 (L-R), (**b**) variation 2 (B-F), (**c**) variation 3 (R-L), and (**d**) variation 4 (B-F). of the ToI in a given frame by using the frame-by-frame marker detection algorithm (Algorithm 2). Focus precision is the distance between the center of the frame (\(scene_{center}=960\times 540\) in _pixels_) and the marker position. ```
1. Input video \(\leftarrow\) OpenCV frame extractor. 2. Identify reference marker in extracted frames. 3. Compute position (\(ref_{mark}^{pos}=(x,y)\)) of the reference marker in extracted frames. 4. Record and continue the process until last frame. ```  
**Algorithm 2** Frame-by-Frame Marker Detection Algorithm  
**Variation 1:** Figure 9 shows the focus precision from the center of the frame to the position of the ToI marker. In variation 1, each ToI was tracked until the completion of its respective pattern. Figure 9 represents the focus precision during the tracking of each ToI. It clearly shows that in the case of RC, more deviation occurred because of the abrupt movement/control of the camera. In contrast, GazeGuide provided a very smooth maneuvering functionality to control the camera in a natural and effortless manner. Hence, the achieved focus precision was very less (540 pixels was the maximum observed focus precision) than RC (940 pixels was the maximum observed focus precision). **Variation 2:** Here, all the ToIs were moving simultaneously in their respective patterns, thus giving an impression to the participant as if the ToIs were moving randomly. The participants tracked each ToI for a specific interval before switching to the next ToI. This cycle was repeated twice in the 3-min duration. Figure 10 clearly shows that the maximum focus precision was higher in the case of RC (1000 pixels) than in that of GazeGuide (650 pixels). Therefore, we inferred that throughout the experiment, ToI was tracked successfully with a significantly low focus precision. Figure 11 presents the overall focus precision for both the variations. It clearly shows that for variation 1, GazeGuide (\(SD=137.89\)) achieved 48.96% more accuracy than RC (\(SD=227.29\)), whereas for variation 2, GazeGuide (\(SD=60.59\)) achieved 81.52% more accuracy than RC (\(SD=143.98\)). Upon considering the overall performance of the participants, we concluded that GazeGuide achieved significantly outstanding performance even when the ToIs moved simultaneously. Figure 9: Experiment 2 focus precision (pixels) for variation 1 (**a**) RC, (**b**) GazeGuide. **Change in Viewpoint:** To compute the change in viewpoint, unique ArUco markers were placed at different locations within the field of view. These static markers (highlighted in black in Figure 6) specified the position of the static markers in a given frame by using the frame-by-frame marker detection Algorithm 2. These positions indicated the changes in the viewpoint (\(x,y\) in pixels). Figure 12 illustrates the obtained viewpoint changes during variation 1 on the basis of the static marker position (\(x,y\)) in the frame. We observed that there were more viewpoint changes and abrupt movements in the case of the RC method than in that of GazeGuide, mainly because of two reasons: (1) GazeGuide adopted incremental changes in the camera movement on the basis of the eye-gaze, whereas the RC method led to random changes in the camera movement depending on the participants' response time.