METHOD OF DETERMINING CHROMATICITY OF PHOTOGRAPH OF DOCUMENT HOLDER FROM DOCUMENT IMAGE Russian patent published in 2024 - IPC G06T7/90 

FIELD: verification of documents images authenticity.

SUBSTANCE: in the disclosed solution, a color image of a document page in the RGB model is obtained under uncontrolled shooting conditions and the following steps are carried out: color normalization of the image of the document page, constructing a color pixel mask of the face, analyzing the color pixel mask of the face, at that, document image normalization consists of two stages: stabilization of document image pixel values range and light source color compensation, to obtain a mask of colored pixels of the face, two auxiliary masks are constructed: a face mask relative to the background and a saturated pixel mask, to make the final decision on the chromaticity of the face image, the ratio of the area occupied by the pixels included in the color pixel mask of the face to the area of the photo zone is considered, note here that if this ratio exceeds the preset threshold, the face image is considered to be colored, otherwise it is considered to be gray.

EFFECT: determination of chromaticity of the photograph of the owner of the document from the image of the document, ensuring stability of operation under different lighting conditions, stable operation when recording an analyzed image with the help of various capture devices and in case of errors of their color calibration.

1 cl, 3 dwg