Idemia Identity & Security France

Morpho

Safran Identity & Security

Aldo Maalouf

Mokrane Malek

Sylvaine Picard

Florence Guillemot

Remy Chiu

Rémy Chiu

A method of deblurring an observed image acquired by an image sensor in order to determine an observable image corresponding to the deblurred observed image. The observable image and the observed image each are formed by a set of pixels defined by at least one numerical value. The method involves expressing the observable image as a solution minimizing a Tikhonov functional defined by the observed image, applying a spreading function at the point of the image sensor and applying a wavelet transform operator. The Tikhonov functional is expressed as a sum of at least two terms. The method further involves determining the observable image by implementing an iterative projection algorithm released on a closed convex, at each iteration of which, the successive application of a projection operator associated with each of the terms of the Tikhonov functional.

Method for deblurring an image

A method for determining a point spread function of an imaging system. The method includes: for each position in a plurality of positions of a target in an optical field of the imaging system: acquiring an image of the target, referred to as the real image; obtaining a synthetic image of the target representing a digital model of the target adjusted to a zone of the real image corresponding to the target so that the model coincides with the zone; estimating the point spread function using the real image and the synthetic image; and calculating an optical transfer function by applying a Fourier transform to the point spread function; calculating an average optical transfer function from the optical transfer functions calculated for each position in the plurality of positions; and obtaining an average point spread function by applying an inverse Fourier transform to the average optical transfer function.

Method for determining a point spread function of an imaging system

The invention relates to a method, for determining a distance between an object with respect to an imaging system, improving the reconstruction of images of objects imaged by an imaging system and improving the resolution of the images obtained.

Method for estimating the distance of an object from an imaging system

A method for characterizing material in which a surface is formed, by analysis of speckles generated on the surface by a coherent light beam by performing the computation of an autocorrelation function of the light intensity on the image and computation of the value of at least one criterion set up from said function, setting up an autocorrelation matrix of the light intensity of the image, computation of the discrete cosine transform of said matrix, and computation of the value of a characterization criterion such as the average on the image of the matrix trace obtained by the discrete cosine transform of the autocorrelation matrix, and computation of the value of at least one representative criterion of a phase shift distribution of the light beams diffused by the surface, said computation comprising computation of a wavelet transform of the image, and computation of the value of at least one criterion from the following group: average of the phases of the wavelet coefficients on the image, or standard deviation of the phases of the wavelet coefficients on the image.

Growing community of inventors

Issy les Moulineaux, France

Aldo Maalouf