Abstract: In some examples, a smartphone or tablet includes a device able to generate a digital identifier of a copy that includes at least one print image. The device includes at least one optoelectronic detection device that detects the at least one print image and creates a representation that includes a multiplicity of pixels. The device further includes a unit that evaluates brightness intensities of the pixels, that segments the representation into multiple fields that each are composed of pixels of the representation, and that provides each of these fields with a piece of position information. The unit also ascertains, in each of these fields of adjoining pixels, a difference in their respective brightness intensities, and displays the differences as a frequency distribution. A display device further displays the digital identifier of the respective copy of the relevant printed product in the form of a graphical and/or alphanumerical display.

Abstract: In some examples, a smartphone or tablet includes a device able to generate a digital identifier of a copy that includes at least one print image. The device includes at least one optoelectronic detection device that detects the at least one print image and creates a representation that includes a multiplicity of pixels. The device further includes a unit that evaluates brightness intensities of the pixels, that segments the representation into multiple fields that each are composed of pixels of the representation, and that provides each of these fields with a piece of position information. The unit also ascertains, in each of these fields of adjoining pixels, a difference in their respective brightness intensities, and displays the differences as a frequency distribution. A display device further displays the digital identifier of the respective copy of the relevant printed product in the form of a graphical and/or alphanumerical display.

Abstract: A method of authenticating security documents and a mobile device, especially a smartphone, programmed to carry out the method, based on an analysis of features which are produced by intaglio printing, which analysis involves a decomposition of sample images of a candidate document to be authenticated based on Wavelets, each sample image being digitally processed by performing a Wavelet transform of the sample image in order to derive a set of classification features. The method is based on an adaptive approach, which includes the following steps: —prior to carrying out the Wavelet transform, defining a categorization map containing local information about different intaglio line structures that are found on the security documents; —carrying out a Wavelet selection amongst a pool of Wavelet types based on the categorization map; and —performing the Wavelet transform of the sample image on the basis of the selected Wavelet.

Abstract: A method of authenticating security documents and a mobile device, especially a smartphone, programmed to carry out the method, based on an analysis of features which are produced by intaglio printing, which analysis involves a decomposition of sample images of a candidate document to be authenticated based on Wavelets, each sample image being digitally processed by performing a Wavelet transform of the sample image in order to derive a set of classification features. The method is based on an adaptive approach, which includes the following steps: —prior to carrying out the Wavelet transform, defining a categorization map containing local information about different intaglio line structures that are found on the security documents; —carrying out a Wavelet selection amongst a pool of Wavelet types based on the categorization map; and —performing the Wavelet transform of the sample image on the basis of the selected Wavelet.