Reasearch Of The Real-time Evaluation Of The Camouflage Effectiveness Of An Infrared Target Under Complex Background Conditions

In modern high technique war,infrared camouflage has been one of the major means for battlefield targets to improve their survivability,in order to counter the threat from infrared reconnaissance and guidance weapons.However,under complex background conditions,the infrared camouflage effectiveness of a target dynamically changes with the changes of weather conditions,the radiation characteristics of the target itself and the background.Thus,it is of great importance to dynamically evaluate the realtime infrared camoufalge effectiveness of a target.This dissertation presented the realtime evaluation of the camouflage effectiveness of an infrared target under complex background conditions by quantifying the camouflage effectiveness of an infrared target based on the construction of the evaluation system.The main research contents are summarized as follows:(1)The fundamental theories and methods about the infrared camouflage effectivenss evalution of a target were summarized and analysed.The basic principle of infrared camouflage techniques was explained.The classifications of the methods for the optical camouflage effectivenss evalution of a target were discussed and the technique details of these methods were also analysed.In addition,the principle of infrared camouflage techniques was laid special streess on analysing.This dissertation also focused on the theoretical basis of introducing the visual saliency and fractal theory into the field of the infrared camouflage effectivenss evalution of a target.(2)The infrared camouflage effectivenss evalution algorithm of a target based on the image saliency theory was conducted.The real infrared images of the target and its coressponding background were captured in different weather conditions after the field experiment design details which included the design of simulate targets,the selection of backgrounds and the expriment process were disscussed.Based on the iamge saliency theory,the algorithm principle and workflow concerning the camouflage effectiveness evaluation of infrared targets were analysed.The concrete algorithm details were discussed from five aspects including the establishment of evaluation index system,the extraction of image features,the fusion stategy of image features,the interior saliency of the target and the quantization of the infrared camouflage effectiveness of the targets.Through the pure mathematical computation,the quantized metric for the infrared camouflage effectiveness of targets was obtained in a comprehensive image features framework.The exprimental results showed that this algorithm could be used to directly differentiate the camouflage effectiveness of the different targets under the same conditions or one target under different conditions,which proved that the quantized metric could well reflect the real infrared camoufalge effectiveness of a target in the corresponding backgrounds.(3)An alternative approach to evaluation of the infrared camouflage effectiveness of a target via a multi-fractal method was studied.From the perspective of measuring the self-similarity of the target and its corresponding background,the multifractal spectra of the target region and the background regions in an infrared image were calculated and then the different spectrum shape features among these spectra were used to analyze the camouflage effectiveness of the target qualitatively and quantitatively.The results demonstrated that this algorithm could adequately utilize the interior texture structure information of the target and its corresponding background thus effectively measured the self-similarity of the target and background.Similarly,this algorithm could be used to compare the camouflage effectiveness of the different targets under the same conditions or the relative camouflage quality of one target under different conditions.The difficulty in the quantification of the complex interior texture structure information was worked out,which was of significance for the comprehensive evalution of the camouflage effectiveness of a target.(4)To study the realtime evaluation of the camouflage effectiveness of an infrared target under complex background conditions,an analysis system was designed.The total design scheme was constructed in detail from five aspects including the workflow,the design principle,the software/hardware design scheme,the design of functional modules and the design of interface about the system.The design schemes of fundamental functional modules in the system were also discussed in detail.(5)The dynamic evaluation of the infrared camouflage effectiveness of targets was researched.During the complete observation period,the surface temperature changes of the target were monitored and recorded.The real infrared images of the target and its coressponding background were captured under the variational weather conditions.Based on these,the quantized infrared camouflage effectiveness of targets was obtained and thus the dynamic change rule curves of the infrared camouflage effectiveness of these targets were acquired which could directly show the dynamic changes of the infrared camouflage effectiveness of the target due to the changes of the weather conditons.Based on the online infrared image dataset,the proposed algorithm was used to cope with infrared image sequence and the infrared camouflage effectiveness of a target in the image sequence was evaluated.The results indicated that this method was robust and universal.It could be extended to process most of infrared camoufalge images under different backgrounds and the realtime infrared image sequences.Based on this algorithm,the evaluation results of the infrared camoufalge effectiveness could be calculated within 0.5 seconds,which could well satisfy the requirement of grasping the dynamic changes of the realtime camoufalge effectiveness of targets.