Research On Image Edge Ehancement Based Upon Fractional Orbital Angular Momentum Of Photon

As an important application direction in optical information processing,image edge enhancement plays a non-substitutable role in image analysis,target recognition and image coding.Since the radial Hilbert transform is proposed by Daviset and his colleagues,helical phase filtering shows obvious advantages in image edge enhancement compared with traditional digital image processing.Because vortex beam of fractional orbital angular momentum of photon which known as fractional order helical phase filtering.has spiral phase wave front with a black vortex core and a radial opening special beam.It has gradually become a hot spot of research.Image edge enhancement based on fractional orbital angular momentum of photon is studied in this dissertation.The main contents of this dissertation are as follows:Firstly,in this dissertation,in terms of the principle of radial Hilbert transform,4f optical filtering system of an image edge enhancement based on fractional orbital angular momentum of photon is established.According to the theoretical model of image edge enhancement based on spiral phase filtering of integal quantum number,an image edge enhancement model based on fractional orbital angular momentum of photon is constructed and analyzed theoretically.Secondly,according to the different edge types of the images,the theoretical simulation and verification of the typical images based on fractional orbital angular momentum of photon are carried out.the rectangle and the circle,representing the linear edge and the curvilinear edge respectively.According to the contrast value of edge enhancement,the optimal quantum number of linear edge enhancement is1 and curve edge enhancement of fractional orbital angular momentum of photon is 1.1.Then,it is proved theoretically that the magnitude of the quantum number influence the depth of edge enhancement based on fractional orbital angular momentum of photon.The optimization number of edge enhancement of complex images based on fractional orbital angular momentum of photon is 1.1.I qualitatively compare and analyze the images of fractional orbital angular momentum of photon and digital image processing.The advantages are summarized as follows: image relief on the edge of the image,fine edge response,fast image processing,and real-time image processing.Finally,it is theoretically proved that the noise mode and the filtering mode have little influence on the image edge enhancement of the fractional orbital angular momentum of photon,and do not affect the change trend of the signal to noise ratio with the variance.By calculating the signal to noise ratio of the processed image.The results show that when salt and pepper noise with a variance of 0.04 is added,signal to noise ratio of the edge enhancement based on the fractional orbital angular momentum of photon is 251.6753,the correlation is 0.9999,signal to noise ratio of the edge enhancement using the Sobel operator and the Roberts operator is 170.8967,168.3700,the correlation degree of 0.7093,0.6765.So the image edge of the fractional orbital angular momentum of photon has higher signal-to-noise ratio and less influence by noise.