Research On Online Detection Method Of Ceramic Tile Color Difference Based On Image Processing

With the continuous improvement of living standards,people no longer only pay attention to the quality of interior decoration,but also emphasize on aesthetics.Ceramic tiles are one of the important materials for interior decoration,and therefore the requirements for the color of ceramic tiles has been improved.As a result of the uneven dyeing during production,differences on the color of the tiles are inevitable.At present,most of the color difference detection of ceramic tiles depends on manual detection.But people’s vision can be tired,leading to unpleasant results,such as missing or false detection,and the low efficiency.Therefore,it is of great practical significance to develop a good on-line detection method of ceramic tile color difference for improving the automation level of China’s ceramic tile industry.Based on the existing on-line detection methods of ceramic tile color difference,this thesis has furtherly studied and designed a reasonable detection scheme by consulting relevant data.The main parts of the research are as follows:Firstly,the hardware selection of ceramic tile color difference online detection system is studied in detail.Including calculating the theoretical selection of image acquisition camera and optical lens,analyzing the relationship between camera and lens,and comparing the advantages and disadvantages between CCD and CMOS;the characteristics of several common lighting sources are analyzed;Finally,LED is selected as the light source of this system,and a reasonable lighting mode is designed.The selections of other hardware related to the system are completed.During the experiment,several common methods of color space,image filtering and image segmentation are analyzed and compared.The scheme of median filtering and threshold segmentation for color tiles based on HSV color space is selected at last.In the aspect of color difference detection of color tiles,the histogram intersection method based on HSV color space and the color difference detection method based on CIELAB color space are compared.Combining with the actual requirements,the histogram intersection method based on HSV color space is finally selected as the method of on-line color difference detection of ceramic tiles.Combined with the experiment,the similarity value and the result of color difference detection in CIELAB color space are analyzed in detail.The feasibility of this method is proved.Then the relationship between similarity value and color difference grade is established.Finally,a simple human-computer interaction interface is made.The experiment proves that the research method proposed in this thesis solves the problem of online color difference detection of colorful ceramic tiles with decorative pattern.