The Application And Research Of Borehole Wall Image Acquisition And Processing Technology

With the continuous progress of science and technology, the methods and means for geological exploration change constantly, during this process, using borehole digital camera technique to obtain the realistic panorama image of the Borehole wall has become one of the major ways to conduct geological analysis in geological analysis. Currently, an increasing number of researchers begin to pay attention to the application of panoramic camera technology in geological exploration, however, the existing methods of getting Borehole wall image have some shortcomings such as high cost of the equipment, complex process, unsatisfactory result of image splicing, etc.Based on the methods of drilling hole logging and the technology of image formation for borehole wall, taken drill hole wall as the research object, by controlling the well depth and projecting the 360-degree cylindrical space of hole wall under the well onto plane, we can get the ring images of hole wall, then unfold, registration and fusion the images to acquire the realistic image of the borehole wall. Aiming at that there are large deviation for determining circle center of borehole wall and obvious splicing traces during image mosaic concerning the traditional algorithm, this paper firstly introduces the improved seed filling algorithm to accurately identify the circle center of borehole wall image, and then adopted the improved, Bezier curves approximation algorithm and difference image matching principle to mosaic the image for achieving a smooth transition between images with no stitching traces.The main contents of this paper can be summarized as follows:①Discusses and analyzes the borehole wall image acquisition and generation technology research background, status, significance and practical application of the theoretical basis of image processing, and describes the borehole wall image acquisition hardware requirements, key technology and drilling hole imaging camera system principles.②Aiming at that the traditional method for unfolding the borehole wall image have large deviations, this paper introduces the improved seed filling algorithm to accurately identify the center of a circle the borehole wall image and the radius direction, adopts compass azimuth recognition algorithm to accurately identify compass direction and use the Unwrapping algorithm to unfold the borehole wall images clock wisely.③Aiming at that acquiring the borehole wall image has obvious mosaic traces and splicing result is not satisfactory enough concerning the current method, we introduce the median filtering algorithm to filter the borehole wall image noise, and adopt the weighted average method to adjust the image brightness, and then use the improve image matching algorithm to find the differences between adjacent images overlap, and the block-matching algorithm and Grid matching algorithm to register the image, finally we blend them by using Bezier curves approximation algorithm to achieve a smooth transition between images.④Based on the methods and design proposed in this paper, we have realized the borehole wall image acquisition system, and have actually tested this system in the geological Instrument .Currently, system has been applied to actual project.Practical application on geological exploration shows that the image mosaic technique presented in this paper is simple, flexible, efficient, and can provide ideal result of the panorama images of the borehole wall, which has an important theoretical and engineering value in the field of geological exploration.