Research On The Determination Of Vitamin C Content Based On Image Color Feature Extraction

Vitamin C,also known as ascorbic acid,is an essential vitamin for the human body,and the human body itself can not synthesize vitamin C,mainly through fruits,vegetables and drugs intake of vitamin C,excessive intake will cause kidney damage.Therefore,it is particularly important to develop a simple and rapid method and instrument for the determination of vitamin C.In this thesis,the image color feature extraction technology is applied to vitamin C content measurement,using digital camera instead of the traditional photoelectric detection unit,combined with computer image processing and data analysis,the relationship between different color components and vitamin C concentration is studied,the vitamin C content determination model is established,and the vitamin C content determination is realized.The main research results are as follows.(1)Based on the visible light camera and color reaction,a visible light vitamin C concentration measurement system is established.An image acquisition device and image analysis software based on visible light camera are designed to collect the image information of vitamin C solution after color reaction and extract the color features of the image.Through nonlinear,linear and multivariate data fitting,the determination model of color characteristics and vitamin C concentration is established.The model is applied to the standard vitamin C solution and the actual sample,and the multivariate fitting model is the best.The detection range is0.81–20.000μg/m L(R~2=0.9994),LOD is 0.240μg/m L,LOQ is 0.81μg/m L,accuracy is 98.95%,and precision is determined with an RSD of 0.73%.A comparison of the results confirmed that the proposed method’s accuracy is higher than that of the spectrophotometric method.The proposed method has a simple design and facilitates easy operation,and the cost of the equipment is only 206.32 yuan.(2)Based on the visible light vitamin C concentration measurement system,a new method of infrared camera and iodine turbidimetry is proposed.According to the redox relationship between vitamin C and iodine,the content of vitamin C is determined by infrared camera turbidimetry.The light emitted by the infrared light-emitting diode(LED)is absorbed and scattered when it penetrated the residual iodine suspension.The transmitted light is captured by infrared camera to form a digital image.The color feature and gray value of the image are extracted,and the determination model of color feature and vitamin C concentration is established.The model is compared with the spectrophotometric method,which is consistent and more accurate than the spectrophotometric method.(3)Aiming at the problem that the color feature extraction of image is easily affected by illumination,based on the color constancy theory,the de illumination algorithm is applied to the images collected by the image acquisition device.The influence of different algorithms on the experimental results is explored.Among them,MSR algorithm has the best processing effect,good color restoration degree and clear edge retention,to reduce the influence of illumination on image color feature extraction as much as possible.This thesis focuses on the measurement of vitamin C,establishes an image-based vitamin C measurement model,realizes two vitamin C measurement methods based on visible light image combined with color reaction and infrared image combined with iodine turbidimetry,provides a new idea for material measurement,widens the application field of computer,and has important academic value and application prospect.