Achieving reliable acoustic wireless video transmissions in the extreme and uncertain underwater environment is a challenge due to the limited bandwidth and the error-prone nature of the channel. Aiming at optimizing the received video quality and the user's experience, an adaptive solution for underwater video transmissions is proposed that is specifically designed for Multi-Input Multi-Output (MIMO -based Software-Defined Acoustic Modems (SDAMs . To keep the video distortion under an acceptable threshold and to keep the Physical-Layer Throughput (PLT high, cross-layer techniques utilizing diversity-spatial multiplexing and Unequal Error Protection (UEP are presented along with the scalable video compression at the application layer. Specifically, the scalability of the utilized SDAM with high processing capabilities is exploited in the proposed structure along with the temporal, spatial, and quality scalability of the Scalable Video Coding (SVC H.264/MPEG-4 AVC compression standard. The transmitter broadcasts one video stream and realizes multicasting at different users. Experimental results at the Sonny Werblin Recreation Center, Rutgers University-NJ, are presented. Several scenarios for unknown channels at the transmitter are experimentally considered when the hydrophones are placed in different locations in the pool to achieve the required SVC-based video Quality of Service (QoS and Quality of Experience (QoE given the channel state information and the robustness of different SVC scalability. The video quality level is determined by the best communication link while the transmission scheme is decided based on the worst communication link, which guarantees that each user is able to receive the video with appropriate quality.
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Adaptive Underwater Video Transmission via Software-Defined MIMO Acoustic Modems
Video signal transmission enables a wide range of applications in the underwater environment; such as coastal and tactical multimedia surveillance, undersea/offshore exploration, oil pipe/bridge inspection, video monitoring of geologica/biological processes from the seafloor to the air-sea interface-that all require real-time multimedia acquisition and classification. Yet, it is a challenge to achieve an efficient and reliable video transmission, due to the spectrum limitations underwater and also the error prone nature of the acoustic channel. In this paper, we propose a pairwise scheme to manage the video distortion-rate tradeoff for underwater video transmission. The proposed Multi-input Multi-output (MIMO)-based Software-Defined Acoustic Radio (SDAR) system adapts itself to meet the needs of both video compression and underwater channel in a timely manner from one hand, and keeps the overall video distortion-caused by the coder/decoder and channel-under an acceptable threshold from the other hand. The scalability of Universal Software Radio Peripheral (USRP) with high processing capabilities is exploited in the proposed structure along with the temporal, spatial and quality scalability of Scalable Video Coding (SVC) H.264/MPEG-4 AVC compression standard. Experimental results at Sonny Werblin Recreation Center, Rutgers University, as well as simulations are presented, while more experiments are in-progress to evaluate the performance of our testbed in more challenging environments such as in the Raritan River, New Jersey.
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- Award ID(s):
- 1763709
- NSF-PAR ID:
- 10112874
- Date Published:
- Journal Name:
- OCEANS 2018 MTS/IEEE Charleston
- Page Range / eLocation ID:
- 1 to 6
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/OCEANS.2018.8604782
