To Slide or Not to Slide: Exploring Techniques for Comparing Immersive Videos

Immersive videos (IVs) provide 360{\deg} environments that create a strong sense of presence and spatial exploration. Unlike traditional videos, IVs distribute information across multiple directions, making comparison cognitively demanding and highly dependent on interaction techniques. With the growing adoption of IVs, effective comparison techniques have become an essential yet underexplored area of research. Inspired by the "sliding" concept in 2D media comparison, we integrate two established comparison strategies from the literature--toggle and side-by-side--to support IV comparison with greater flexibility. For an in-depth understanding of different strategies, we adapt and implement five IV comparison techniques across VR and 2D environments: SlideInVR, ToggleInVR, SlideIn2D, ToggleIn2D, and SideBySideIn2D. We then conduct a user study (N=20) to examine how these techniques shape users' perceptions, strategies, and workflows. Our findings provide empirical insights into the strengths and limitations of each technique, underscoring the need to switch between comparison approaches across scenarios. Notably, participants consistently rate SlideInVR and SlideIn2D as the most flexible and favorite methods for IV comparison.