A method and image processing apparatus for image visibility restoration are provided. The method includes the following steps: receiving an input hazy image including input pixels; obtaining edge information of each of the input pixels according to a median filtering operation and a dark channel; determining a transmission map according to each of the input pixels and atmospheric light associated with the input hazy image in each color channel; obtaining a refined transmission map according to the edge information and the transmission map; adjusting the refined transmission map by performing a gamma correction operation thereon to obtain an enhanced transmission map; determining a color difference value corresponding to each of the color channels; recovering scene radiance for each of the input pixels in each of the color channels according to the corresponding color difference value, the enhanced transmission map, and the atmospheric light to produce and output a de-hazed image.

Method and image processing apparatus for image visibility restoration

Methods and systems for dehazing images with increased accuracy and reduced error enhancement. In particular, one or more embodiments estimate a transmission map representing an amount of unscattered light reflected from objects in an input image. One or more embodiments refine the transmission map to obtain transmission information consistent with a depth of the objects in the input image. One or more embodiments also determine a radiance gradient for the input image. One or more embodiments generate an output image from the input image by removing haze based on the refined transmission map and preventing error enhancement based on the determined radiance gradient.

Dehazing photos and videos using visual artifact suppression

The invention discloses a video defogging method and a video defogging system. The technical scheme is that the method comprises the following steps: inputting a foggy video frame RGB (Red Green Blue) image, calculating an atmospherical light value and a transmissivity image, taking the transmissivity image as a guide filter, and correcting the image to obtain a defogged video frame. The calculation of the atmospherical light value is performed in two conditions: if the transmissivity image is unavailable, calculating to obtain the atmospherical light value according to a brighter pixel region (specially bright pixels in addition to subtitles, light and others) in the image; if the transmissivity image is available, calculating to obtain the atmospherical light value according to pixels in a part of region with lowest transmissivity. According to the video defogging method, the problems that a defogging algorithm is slow in speed, and the atmospherical light value is interfered by the light, subtitles and others which are not in harmony with a screen can be solved, haze can be effectively eliminated, and the primary detailed features of the image can be reserved, therefore the method has the advantages of low computation complexity, harmonious in all defogged regions of the image and the like; furthermore, the method can be used for the preptreatment for the foggy video in the applications of video surveillance and the like, and can be beneficial for subsequent video analysis and manually watching the defogged videos.

Video defogging method and system

The invention provides a method and a device for recognizing a human face in a fog day image. The method for recognizing the human face in the fog day image comprises a first step of processing an input color image by utilizing a dark channel priority defogging method and regarding the processed image as a first image, a second step of detecting the human face in the first image by using a preset human face detector to extract a human face image in the first image, and a third step of recognizing the human face image by adopting an algorithm which combines principal component analysis and linear identification analysis to output the recognizing result. Defogging process is started before the human face is recognized aiming at the image shot at a specific scene in a foggy day, defogging calculated amount is small, so that efficiency and speed of image process are guaranteed, recognizing efficiency in foggy environment is effectively improved, the purpose that the human face recognizing is not affected by the foggy environment is guaranteed, and human face recognizing effect is guaranteed.

Method and device for recognizing human face in fog day image

The invention belongs to the field of information processing in the information engineering field, and particularly relates to a water surface moving platform visual system image analyzing and processing method. The method includes the steps of image fog removal, graying, image stabilizing, target segmenting, binaryzation, shape characteristic extracting, texture characteristic extracting, establishing of target characteristic bases of different types, and neural network training and testing. The water surface moving platform visual system image analyzing and processing method has the advantages of being high in processing instantaneity, high in image comprehensive analyzing and processing capacity, wide in application range and the like; video image fog removal and electronic image stabilizing can be conducted on a water surface moving platform in real time under the severe weather conditions such as sea fog, and various types of targets on the water surface can be recognized.

Water surface moving platform visual system image analyzing and processing method

The invention relates to a video image defogging method based on self-adapting allowance and belongs to the field of video image processing. The method includes: building a single-frame image foggy day degradation model, estimating a rough transmission picture by aid of dark channel prior, obtaining a refined transmission by aid of a guide filter, judging whether images contain a large bright area, obtaining the rectified transmission picture and restoring a fog-free image. The method is applicable to video images with basically unchanged scenes like vide monitoring and video images with dynamically changing scenes, and can be widely applied to outdoor monitoring, remote sensing, intelligent transportation and other aspects.

Yan Piao

Papers

Video image defogging method based on self-adapting allowance