Study On The Volume Measurement Method Of Irregular Object Based On Computer Vision

Volume is used to classify, recognize in some industries or special fields, which relates to calculate the volume of irregular object, such as coals on transmission belt, large material stacks, cultural relics, human organs, etc. In this paper the volume of irregular object is obtained by computer vision technology through non-contact measurement. This paper mainly researches the following four aspects:(1)Acquiring method for image is researched. The image acquisition device comprises two annular lights, three cameras(left, right and top). Three cameras are connected with image acquisition cards in the computer.Three images are obtained by image acquisition device respectively, the left view image, right view image and top view image.This image acquisition is prepared for volume measurement. The acquisition system is suitable for the irregular shape is not particularly complex, and bottom invagination is less with uniform color.(2)An image inpainting method based on Bayesian compressive sensing and morphological component analysis is researched. Image preprocessing includes graying, enhancement, inpainting, segmentation. The image is grayed by average method, enhanced by homomorphic filtering method.Image segmentation use CV model. For a damaged image, it would cause a greater error, so before measuring volume the first important thing is need to repair the damaged image. To the question that the image of irregular object, an image inpainting method based on Bayesian compressive sensing and morphological component analysis is introduced. This method transforms the sparsity for structure and texture, then gets the posterior distribution functions of the two sparse coefficients through Bayesian compressive sensing. The inpainting image is obtained through distribution functions. The proposed method has a good performance compared with the traditional methods through SSIM values and PSNR values.(3)The recovery of the heights for irregular objects is researched. Analysis the relationship between height and gray through the principle of shape from shading, then the relationship is established. Gray values are normalized firstly to avoid the impact of singular points. Then heights are obtained through gray values, the heights of stones and eggs are obtained through this method. The recovery structure of stone is similar to the actual structure through simulation. Cool part means the height value is low. Warm part means the height value is high.(4)The method of calculating volume is researched. First the heights of stones are obtained. Pixel volumes of stones and eggs are calculated through the total height. The actual volumes are obtained through pixel equivalent values. The absolute errors and relative errors are used to analysis the measurement results. Use the actual volume of stones and eggs to verify the effectiveness of the method.The heights of irregular objects are recovered through shadings of images. Tested the results with the actual volume by drainage method, the relative errors are about 5% mostly, and it can meet the measurement requirements of irregular objects in a certain extent.