将与矿石原子序数相关的R值图像映射方法运用在矿物识别中能够较准确的识别矿石,但是由于R值的推导直接忽略了矿石厚度的影响,这必然会导致R值识别结果受厚度的影响较大,所以由R值算法为基础的图像映射方法必然存在一定的缺陷.而与矿石厚度及密度相关的T值算法保留了厚度和密度两个重要参数,因此使用T值识别算法得到的图像信息量将会更多.使用T值图像映射方法对采集到的双能X射线透射矿石的图像进行验证.首先,对铝和铜试件进行T值与R值曲线拟合识别算法的优劣对比,经过试验可知,R值曲线拟合的相关系数分别为0.900 24和0.880 31,而T值曲线拟合的相关系数则分别达到了 0.998 4和0.991 16,因此可得出T值识别算法相对减小了厚度对物质识别的影响且T值算法相比R值算法更优.本文在此研究的基础上提出一种基于T值的图像映射方法.该方法首先利用灰度值来代替信号强度值计算出T值,得到由T值作为等大小的灰度图像,然后再先后使用数学形态学图像处理以及中值滤波技术对图像进行清晰化处理,最后使用RGB伪彩色处理得到最终的图像.经过试验对比可知,T值图像映射方法相较于R值图像映射方法不仅在运行速度上得到了提高,而且在图像清晰度以及矿石识别的准确率上都得到了较好的提升.
The R-value image mapping method related to ore atomic number can identify ores more accurately when applied to mineral identification,but owing to the deduction of R-value directly ignores the influence of orethickness,it is greatly affected by the thickness,so this image mapping method has certain defects.The T-valuealgorithm related to the thickness and density of ore retains the two important parameters,therefore,using T-value will obtained more image information.T-value image mapping method is used to verify the acquireddual energy X-ray transmission image of ore.First of all,advantages and disadvantages of the curve fittingbetween T-value and R-value recognition algorithm are compared.Through experiments,it can be seen that thecorelation coefficients of R-value curve fitting were 0.900 24 and 0.880 31,while the correlation coefficients of T-value curve fitting reach 0.998 4 and 0.991 16 respectively.Therefore,the T-value recognition algorithmrelatively reduces the influence of thickness on material recognition and the T-value algorithm is better than R-value algorithm.Therefore,an image mapping method based on T-value is proposed on the basis of thisresearch.In which the intensity of grayscale substitution is adopted to calculate the T-value,which is then used asthe equal size image as the grayscale,and then the mathematical morphology image processing and median filtertechnology are used successively to process the image sharpness,and finally RGB pseudo-color processing is usedto obtain the final image.According to the experimental result,The T-valued image mapping method not onlyimproves the running speed compared with the R-valued image mapping method,but also better in enhancing theimage clarity and ore recognition accuracy.