Recovering Depth from Still Images for Underwater Dehazing Using Deep Learning

Estimating depth from a single image is a challenging problem, but it is also interestingdue to the large amount of applications, such as underwater image dehazing. In this paper, a newperspective is provided; by taking advantage of the underwater haze that may provide a strong cue tothe depth of the scene, a neural network can be used to estimate it. Using this approach the depthmapcan be used in a dehazing method to enhance the image and recover original colors, offering abetter input to image recognition algorithms and, thus, improving the robot performance duringvision-based tasks such as object detection and characterization of the seafloor. Experiments areconducted on different datasets that cover a wide variety of textures and conditions, while using adense stereo depthmap as ground truth for training, validation and testing. The results show that theneural network outperforms other alternatives, such as the dark channel prior methods and it is ableto accurately estimate depth from a single image after a training stage with depth information

3D Information from Scattering Media Images

Scattering media environments are real-world conditions that occur often, in daily life. Some examples of scattering media are haze, fog, and other bad weather conditions. In these environments, micro-particles in the surrounding media interfere with light propagation and image formation. Thus, images that are captured in these scattering media environments will suffer from low contrast and loss of intensity. This becomes an issue for computer vision methods that employ features found in the scene. To solve this issue, many approaches must estimate the corresponding clear scene prior to further processing. However, the image formation model in scattering media shows potential 3D distance information about the scene encoded implicitly in image intensities. In this paper, we investigate the potential information that can be extracted directly from the scattering media images. We demonstrate the possibility of extracting relative depth in the form of transmission as well as explicit depth maps from single images