Because of dorsal vein properties difference between different persons

for different vein objects not all vein images with high qualities can be acquired when fixing acquisition system parameters

in the paper a new image quality assessment model is proposed according to vein characteristics

moreover

vein image can be acquired through self optimization based on assessment result.First

a measure function based on key information entropy is proposed

which measures vein information completeness;Second

another measure function based on Contourlet decomposition is proposed

which is used to judge whether vein directional information is rich or not;Third

the objective vein image quality assessment model without reference is formed by fusing the two measure functions.In final

iteration elimination method is proposed in order to overcome the defect of steepest descent method

which is easy to fall into local optimum during optimization process.Experiments show the proposed quality assessment model is controllable and can meet the characteristics of human visual system

in the meantime the number of iterations can be reduced effectively through the proposed iteration elimination method

and the real-time requirement of acquisition system can be ensured.