Research on climate change based on carbonate porosity analysis in Jinping, China

saddle line formula. Then, the new RGB value and gray value are used to perform thresholding to obtain a black and white binary image. Based on this, the porosity of the carbonate rock is calculated using the black and white binary image. In this study, the four saddle-line maps were used to calculate the porosities from the polarized light microscope images of the carbon- ate rocks. Fig 5 shows the process of obtaining the porosity from polarized images of the car- bonate rocks using saddle line mapping. Fig 5a–5d show the four saddle-line maps; and e shows the original image and the carbon- ate porosity obtained from the RGB values or gray value using an automaton (saddle line map- ping). The polarized light microscope images of all of the carbonate rocks were used to obtain their porosities using the method illustrated in Fig 5, and Table 1 was obtained. To distinguish it from the background color of the manuscript (white), the binary image is displayed in blue- black instead of white-black. Fig 5 and Table 1 present the results of the porosity study of carbonate rock polarizing microscopic images using saddle line mapping. Based on these results, saddle line mapping is a good algorithm for porosity research involving carbonate image analysis. When saddle line mapping is applied to the finite automata, and different gray values or RGB values are used as the threshold of the finite automata, and the porosity of the carbonate rocks can be better obtained. Fig 4. Optimization of image processing algorithms. https://doi.org/10.1371/journal.pone.0281630.g004 PLOS ONE

Research on climate change based on carbonate porosity analysis in Jinping PLOS ONE | https://doi.org/10.1371/journal.pone.0281630 March 30, 2023 9 / 21