Priority Belief Propagation (priority-BP) algorithm cannot satisfy real-time requirement, and there is much room to improve its computational efficiency. As for its application in image inpainting, the main improvements of priority-BP algorithm focused on information transmission and tag searching. In information transmission step, sparse representation of image was wielded into the first iteration and the initial image information of target area was rapidly updated to provide more accurate prior information for the first iteration, which accelerated information transmission and improved the accuracy of tag trimming and information transmission. In tag searching step, the global searching was integrated with local searching instead of just only global searching so as to improve the construction efficiency of tag set. The improved algorithm was verified by examples. The results show that it has obvious advantage in inpainting images with large size; even with the small size of 120×126, it still improves the Peak Signal-to-Noise Ratio (PSNR) by 1.1 dB compared with original priority-BP algorithm, and reduces time consumption up to 1.2 seconds compared with original priority-BP algorithm. The experimental results indicate that the propsed algorithm can effectively improve the inpainting accuracy and efficiency.

In order to improve the efficiency of power transmission line inspection by Unmanned Aerial Vehicle (UAV), a new method was proposed for detecting broken transmission lines and defects of foreign body based on the perception of line structure. The transmission line image acquired by UAV was easily influenced by the background texture and light, the gradient operators of horizontal and vertical direction which can be used to detect the line width were used to extract line objects in the inspection image. The study on calculation of gestalt perception of similarity, continuity and colinearity connected the intermittent wires into continuous wires. Then the parallel wire groups were further determined through the calculation of parallel relationship between wires. In order to reduce the detection error rate, spacers and stockbridge dampers of wires were recognized based on a local contour feature. Finally, the width change and gray similarity of segmented conductor wire were calculated to detect the broken part of wire and foreign object defect. The experimental results show that the proposed method can detect broken wire strand and foreign object defect efficiently under complicated backgrounds from the transmission line of UAV images.

Images of transmission tower acquired by Unmanned Aerial Vehicle (UAV) have high resolution and complex background, the traditional stitching algorithm using feature points can detect a large number of feature points from background which costs much time and affects the matching accuracy. For solving this problem, a new image mosaic algorithm with quick speed and strong robustness was proposed. To reduce the influence of the background, each image was first segmented into foreground and background based on a new implementation method of salient region detection. To improve the feature point extraction and reduce the computation complexity, transformation matrix was calculated and image registration was completed by ORB (Oriented Features from Accelerated Segment Test (FAST) and Rotated Binary Robust Independent Elementary Features (BRIEF)) feature. Finally, the image mosaic was realized with image fusion method based on multi-scale analysis. The experimental results indicate that the proposed algorithm can complete image mosaic precisely and quickly with satisfactory mosaic effect.

Aiming at not satisfactory defogging effect of the traditional defogging algorithm based on polarized characteristics in heavy fog, a new color space conversion algorithm using dark channel prior for polarization image dehazing was proposed. Compared with the traditional imaging technology, polarization imaging detection technology has remarkable advantages in the target detection and recognition of complex environment. Intensity, polarization degree and polarization angel information are usually used to describe target's polarization information for polarization images. In order to combine the polarization information and defogging model, a method of color space transformation was adopted. Firstly, the polarization information was converted into the components of the brightness, hue, saturation in Hue-Intensity-Saturation (HIS) color space and then the HIS color space was mapped to the Red-Green-Blue (RGB) space. Secondly, the dark channel prior principle was applied to get the dark channel image with the combination of the atmospheric scattering model in haze weather. Finally, the atmospheric transmission rate was elaborated by using softmatting algorithm based on sparse prior of the image. The experimental results show that, compared with the existing polarization defogging algorithm, many technical specifications of defogged images such as standard deviation, entropy, average gradient of the proposed algorithm have been greatly improved in very low visibility conditions. The proposed algorithm can effectively enhance the global contrast in heavy fog weather and improve the identification capability for the polarized images.

Because the unfolded process of three-way conical pipe is complex, the development drawing cannot be completed automatically. This paper introduced a general analytic algorithm about the development of curve oblique based on the thought of symbolic-graphic combination. The equation of two conical intersection line was established by exploring the mathematical model of the skew intersection to the axis of the cone. The intersecting lines in the SolidWorks interface were created by means of VB progamming and were verified through SolidWorks. After setting up flattening curve equation, the development drawing was carried out in the SolidWorks. Thus, the expansion plan of two cones with arbitrary size and skew axises was designed by parametric means on the SolidWorks interface. The unfolding method is reliable and it makes automatic development drawing practical. The results and relevant data also reveal that the algorithm is of fast speed, high precision and strong universality, which can be used for the expansion mapping of a variety of sheet metal parts to facilitate the manufacture of sheet metal parts.