Full-View Non-Equal Quality (Viewport-Dependent)
全视图质量不相等（取决于视口）

Full-View Non-Equal Quality, a technique that falls under the category of Viewport-Dependent streaming for 360-degree videos, is an approach that aims to provide a balance between video quality and bandwidth efficiency by allocating different qualities to different areas of the spherical video based on the viewer’s perspective. Here are the key characteristics of Full-View Non-Equal Quality streaming:

1. Varying Quality Across the Spherical Video: In this method, the entire 360-degree video is divided into different segments or regions, each with varying levels of quality. Unlike Full-View Equal Quality, where all parts have the same quality, this approach allows for a more dynamic allocation of bitrates.

2. Quality Prioritization for the Viewed Area: The regions or segments within the viewer’s current field of view are encoded at a higher quality, while non-viewed areas are encoded at a lower quality. This prioritizes the quality of the video where the viewer is looking.

3. Bandwidth Efficiency: Full-View Non-Equal Quality is more bandwidth-efficient compared to Full-View Equal Quality, as it reduces the quality in non-viewed areas. This approach conserves network resources and allows for smoother streaming.

4. Improved Visual Experience: By optimizing quality allocation for the viewer’s immediate field of view, this method enhances the visual experience and immersion. The viewer perceives higher detail and resolution where they are looking.

5. Dynamic Adaptation: Similar to Viewport-Only Equal Quality, Full-View Non-Equal Quality streaming dynamically adapts the quality based on the viewer’s perspective. It continually shifts the higher quality to the current viewport as the viewer’s gaze changes.

6. Challenges: Implementing Full-View Non-Equal Quality can be complex as it requires real-time tracking of the viewer’s gaze and efficient encoding and delivery mechanisms to adjust the quality in real-time.

7. Optimal for Head-Mounted Displays: This streaming method is well-suited for head-mounted displays (HMDs), such as VR headsets, where precise tracking of the viewer’s head movement and gaze is important for an immersive experience.

Full-View Non-Equal Quality strikes a balance between quality and bandwidth efficiency, making it a practical solution for delivering high-quality 360-degree video content. It ensures that the viewer experiences optimal quality where they are looking, while non-viewed areas are encoded at a lower quality to save bandwidth. As technology advances and streaming protocols evolve, strategies like this one are critical for enhancing the 360-degree video viewing experience.