Amber Gemstones Sorting By Colour

Abstract

The objective of this study is to create computer vision algorithms for autonomous multiclass identification of amber nuggets by their colour. By applying the proposed methods an automated production sorting system has been developed. This system can be used, for example in combination with conveyor systems, and in any other case that requires distinguishing objects of many classes in a high-rate flow of objects. In order to achieve this, the proposed system operates with colour features selection, algorithm for classifier training, grouping, and voting with reject option have been developed. The developed system has been used in an automated amber sorting line to increase the quantities of sorted amber nuggets. The applied algorithms gave 88.21% as the highest accuracy for the amber nugget expert database consisting of 30 classes.

Classification of Objects by Shape Applied to Amber Gemstone Classification

“…Table 4 shows the results of the classification of the basic form data set. Using the same set of photographs taken during the real-time experiment, the method mentioned in [12,13] (i.e., classification by the form using centroid distance function (CDF)) was tested and compared. The results of the method are presented in Table 2.…”

“…This time, the CDF method identified a class in 0.12 s on average, while the proposed SPD method showed an average of 0.01 s. The size of the images and the central processing unit speed influenced the average time of the calculations, but since the data sets were the same and the calculations were made on the same central processing unit (CPU), the proportional speed of both methods could be clearly identified. Using the same set of photographs taken during the real-time experiment, the method mentioned in [12,13] (i.e., classification by the form using centroid distance function (CDF)) was tested and compared. The results of the method are presented in Table 2.…”

Rail-to-Rail CMOS Voltage Buffer Design for LCD Column Drivers

“…The layout of the buffer circuit which is shown in Fig. 2 is drawn using the finger technique by splitting the long gate of one transistor into two, three or more segments connected in parallel and sharing the same diffusion area of the drain and source contacts [27][28][29]. The length L dimensions of transistors have roughly values rather than exact values according to the 0.35 µm technology parameter rules in Microwind Software.…”