Research On Multi-Image Panorama Mosaic Technology

The panoramic image mosaic technology is an important research direction in the field of digital image processing. There has a wide range of important practical value on protection of cultural relics(ancient or ancient text data protection), computer vision, remote sensing image processing, medical image analysis, computer graphics etc.A complete image mosaic process includes image acquisition, image registration, projection and image fusion etc. The key steps are image registration and image fusion. It has to consider the sort of image if the mosaic object is an image sequence. So, this paper focuses on these three points.In image registration, this paper choose an image registration method based on Scale Invariant Feature Transform(SIFT) after study deeply on based on gray information and the fcature of image registration algorithm. Propose an improved matching algorithm which is a distance, angle and Random Sample Conscnsus(RANSAC) combination of the three algorithms. The matching stage is divided into coarse matching and fine matching of two parts. In the coarse matching stage, use the SIFT to combine with distance and angle and weed out mismatches points with similarity. In the fine matching stage, use the RANSAC algorithm purification feature points and obtain the homography between images to complete the registration. The experimental results show that proposed algorithm compare with other algorithm has higher accuracy and time-consuming almost equal. It’s a good matching plan.In image fusion, this paper describes several typical algorithms, and then do experiment on weighted average fusion, fading in and out fusion and pyramid fusion. These experimental results indicate that the weighted average fusion is the simplest but least effective, the fading in and out fusion improve the shortcomings of the weighted average fusion and the effect is good. The pyramid fusion is the best, no obvious defects, but time-consuming higher. Based on the experimental results, choose to use the fading in and out fusion algorithm. In image sorting, using the feature of the image registration stage which are the number of matching points to do sorting. The most number of the matching points is the most likely to have matching relations and then use a probabilistic method to make sure this relations.Based on these, propose an automated panoramic image mosaic program and do experiment. The results indicate that this program can sort the unsorted images automatically, and able to remove the independent images out of the sequence. After image mosaic, the result is good, the speed is reasonable, achieve the intended purpose.