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As a critical sensor for high-level autonomous vehicles, LiDAR's limitations in adverse weather (e.g. rain, fog, snow, etc.) impede the deployment of self-driving cars in all weather conditions. However, studies in literature on LiDAR's performance in harsh conditions are insufficient. In this paper, based on a dataset collected with a popular Near-InfraRed (NIR) ToF LiDAR in a well-controlled artificial fog chamber, we statistically model the LiDAR ranging process in fog conditions through a data-driven approach. Specifically, giving an object at a known distance, our model is able to predict LiDAR measures (range and intensity) under various fog conditions. For a transmitted laser under fog, we first model and predict the minimum visibility required to detect its true range or not. Then, the noisy range and intensity measures are sampled from the probabilistic measurement distributions inferred from the dataset. The performance of the proposed method has been quantitatively and qualitatively evaluated. Experimental results show that our approach can provide a promising performance prediction of the utilized NIR ToF LiDAR under fog, which opens a new gate to the quantitative assessment of adverse weather and contributes to the specification of relevant Operational Domain Designs (ODDs). The developed ROS package is available at:https://github.com/cavayangtao/lanoising.

The ability to sense and understanding the driving environment is a key technology for ADAS and autonomous driving. Human drivers have to pay more visual attention to important or target elements and ignore unnecessary ones present in their field of sight. A model that computes this visual attention of targets in a specific driving environment is essential and useful in supporting autonomous driving, object-specific tracking & detection, driving training, car collision warning, traffic sign detection, etc. In this paper, we propose a new framework of visual attention that can predict important objects in the driving scene using a conditional generative adversarial network. A large scale Visual Attention Driving Database (VADD) of saliency heat-maps is built from existing driving datasets using a saliency mechanism. The proposed framework model takes its strength from these saliency heat-maps as conditioning label variables. The results show that the proposed approach makes us able to predict heat-maps of most important objects in a driving environment.

The complexity of a scene in addition to the need for real-time processing are the main challenges that face any background/foreground separation approach for maritime environment. Recent studies on Low-rank and Sparse Separation (LSS) achieved good performance when compared to traditional background subtraction techniques in segregating the foreground from a complex background. However, the issue of maintaining this type of a separation via an updating mechanism is not well addressed by the majority of LSS approaches. The study presents a tensor based singular value decomposition approach for background/foreground separation. The approach is uniquely designed to deal with most challenges related to a maritime environment such as sea dynamics, boat wakes, variety of foreground objects, and camera jitter. Furthermore, the proposed approach operates incrementally via updating the separation components as opposed to reperforming the decomposition on the entire video sequence when a set of frames arrives. Additionally, a forgetting mechanism is employed in the proposed approach to efficiently handle challenges such as Stationary Foreground Objects (SFOs) and ghost effects. The performance of the proposed method with several state-of-the-art LSS and Non-LSS techniques on videos with complex maritime scenarios are evaluated. The results exhibit better performance over most of the tested challenges and also demonstrate the capability of the proposed method to perform the separation in less computational time.