| To cope with the threat of reconnaissance arising from the wide coverage,long duration and uninterrupted technical characteristics of current battlefield reconnaissance,camouflage technology is gradually developing from static camouflage to dynamic camouflage.Dynamic camouflage technology can achieve real-time integration with the background environment by actively adjusting its camouflage strategy and scheme,to solve the problem of poor camouflage effect of static camouflage targets in cross-territory,cross-time and cross-seasonal situations.As the target camouflage scheme is in real-time dynamic change,the camouflage effect of different schemes varies,and the traditional static camouflage effect evaluation method has many problems when applied to dynamic camouflage targets,while the existing dynamic camouflage effect evaluation method has few published materials and the relevant theoretical system and evaluation method are not perfect.To address the above problems,this paper takes the representative optical adaptive camouflage target in dynamic camouflage technology as the evaluation object,and researches the construction of the evaluation index system,the evaluation model of the effect of the adaptive camouflage scheme and the evaluation model of the camouflage effect of the manoeuvring target in three aspects:(1)Based on the analysis of the characteristics of the adaptive camouflage target and the human eye visual system,the assessment index system was determined.The greyscale similarity,colour similarity,texture similarity,shape similarity,target motion speed,background interference quantity and background interference saliency were selected as the evaluation indexes,and the calculation methods of each index were given.The evaluation data were obtained through target modelling,background modelling,camouflage scheme design and optical image video feature extraction,which provided data support for the subsequent research of the evaluation model.(2)To address the dynamic optical camouflage characteristics of adaptive targets across regions and backgrounds,this paper proposes a comprehensive multi-context camouflage effect evaluation model.Several typical backgrounds in the target activity area are selected,and the greyscale,colour,texture and shape similarity indicators are calculated separately in each background,and the indicators are weighted by the entropy weighting method to obtain the camouflage effect of the adaptive camouflage target in each background.The evaluation results in each background are weighted by the proportion of each background in the target’s active area to obtain the combined camouflage effect of the adaptive target in multiple backgrounds.Compared with previous similarity-based assessment models,the model in this paper extends its applicability in multi-background assessment,making the assessment results more objective and comprehensive,and more consistent with the actual camouflage effect of adaptive targets operating in multiple backgrounds in a large area range.(3)To address the characteristics of adaptive targets in maintaining camouflage effect during manoeuvring and the lack of current methods for assessing the camouflage effect of manoeuvring targets,a model for assessing the camouflage effect of manoeuvring targets is proposed.The camouflage effect of the manoeuvring target is divided into two parts: the effect of the camouflage scheme and the effect of target movement and movement interference in the environment on the camouflage effect.The two components are evaluated separately and a comprehensive index is proposed to characterise the camouflage effect of a target under manoeuvre by combining the results of the two components.The proposed method provides an effective means to assess the camouflage effect of manoeuvring targets and remedies the shortcomings of traditional methods that cannot reflect the characteristics of target and background movements.The proposed method integrates the camouflage effects of targets in multiple contexts and considers the influence of target motion characteristics on the camouflage effects,providing a more reasonable model for assessing the camouflage effects of dynamic camouflage targets.The work done in the thesis enriches the theory of camouflage effect evaluation and can provide reference for dynamic camouflage technology research and adaptive camouflage engineering practice. |
