Autor: |
Lu Yujun, Takuya Fujihashi, Shunsuke Saruwatari, Takashi Watanabe |
Jazyk: |
angličtina |
Rok vydání: |
2021 |
Předmět: |
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Zdroj: |
IEEE Access, Vol 9, Pp 52684-52697 (2021) |
Druh dokumentu: |
article |
ISSN: |
2169-3536 |
DOI: |
10.1109/ACCESS.2021.3067018 |
Popis: |
The existing viewport-adaptive 360-degree video streaming schemes encode tiled 360-degree videos with digital-based compression. However, these schemes cause a cliff effect wherein the headset video quality drops when the channel signal-to-noise ratio (SNR) falls below a certain threshold. To realize high-quality wireless 360-degree video streaming, we propose a novel viewport-adaptive soft delivery scheme for 360-degree videos, called 360Cast+. 360Cast+ skips the non-linear operations in digital-based streaming and adopts power allocation and analog modulation to achieve graceful video quality improvement in unstable wireless links. In particular, 360Cast+ integrates the human vision system (HVS) and projection distortion as a perceptual weight in power allocation operations. A near-optimal low-complexity subcarrier matching algorithm was also adopted to extend 360Cast+ to fading channel environments. To reduce the effect of the prediction error, 360Cast+ uses dynamic linear regression (DLR) to predict the future orientation and future prediction error to extract the extension area around a viewport. The evaluation results demonstrated that the proposed 360Cast+ provides sophisticated video quality irrespective of the prediction error and channel conditions in orthogonal frequency-division multiplexing (OFDM)-based systems. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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