On the Feasibility of Video Streaming through Underwater Acoustic Links

Wireless Remote Control for Underwater Vehicles

“…In a real-time video transmission, in order to avoid the video buffering and causing an undesired delay, we must consider the maximum video bit rate as the bit rate to be transmitted. Maintaining the same proportion obtained in [61], given that BlueROV streams a video with an average bit rate of 11.5 Mbp, we expect a maximum bit rate of 16.5 Mbps.…”

“…BlueROV mounts an HD video camera with a maximum resolution of 1920 × 1080 px at 30 fps, resulting in an average video bit rate of 11.5 Mbps. According to the results we presented in [61], the video bit rate depends on the number of details and items present on the frames and on the level of motion: in general, low-motion quasi-static videos require a lower bit rate than a dynamic video with fast movements, and a video representing only one simple object with a white background requires a lower bit rate than a video showing lots of complex objects and many people with a background composed of mountains, trees, and lakes. For this reason, in the subsea raw video sample considered in [61], the maximum bit rate is related to the moment when the ROV performs quick movements in an environment with complex details.…”

“…The market of HF modems is divided into two segments: low-rate acoustic modems and high-rate acoustic modems. While the former has a price below 2 kEUR and is suitable for low-rate (less than 200 bps) communication in shallow water up to a distance of 200 m [56][57][58], the latter has the same price as MF and LF acoustic modems (between 8 and 10 kEUR, depending on depth rate requirements) and can be used for sending a still-frame slide-show-like video feedback from an underwater vehicle [43,[59][60][61][62] to a control station, as they can perform transmissions with a bit rate of more than 30 kbps [29]. In this paper, we focus on this last type of modem in order to achieve the best performance possible despite the higher price.…”

“…The maximum rate of a LinkQuest [31] modem is 35.7 kbit/s (with a directional beam pattern), while EvoLogics S2CM HS [29] is the off-the-shelf modem that provides the highest bit rate (62.5 kbit/s up to 300 m in good channel conditions, although its actual maximum throughput would typically be about 30 kbit/s). This last modem has been used in [61] to perform in-tank low-quality video streaming, where the transmission bit rate selected by the modem during its initial handshake phase [63] was 31.25 kbps and the actual throughput obtained 20 kbps. In good channel conditions, this performance can also be obtained with other EvoLogics models, such as S2C 48/78 and S2C 42/65.…”

UW-SVC: Scalable Video Coding Transmission for In-Network Underwater Imagery Analysis

“…Despite all these works, the problem of robust video transmission is still unsolved, and achieving high video quality is still a challenge when we consider the limited available bandwidth along with the harsh characteristics of the underwater acoustic channel, which calls for novel highspectral-efficiency in-network collaborative methods. In the area of underwater video, [12] shows the feasibility of video streaming using currently commercially available hardware defined modems. The reconstructed objects can be used in Simultaneous Localization And Mapping (SLAM).…”