Abstract: According to various implementations, a computing device receives an image of a candidate mark and uses the image to create a profile of a feature of the mark. The computing device filters out, from the profile, all spatial frequency components except for a first band of spatial frequency components, resulting in a first filtered profile for the feature. The computing device repeats this filtering process for a second band of spatial frequency components, resulting in a second filtered profile for the feature, and may repeat this filtering process for further spatial frequency bands. The computing device compares the first filtered profile of the candidate mark with an equivalent first filtered profile of a genuine mark, and may repeat this process for further filtered profiles.

Abstract: Methods for determining whether a mark is genuine are described. According to various implementations, a computing device (or logic circuitry thereof) receives (e.g., via a camera or via a communication network) an image of a candidate mark (e.g., a one-dimensional or two-dimensional barcode), uses the image to make measurements of a characteristic of a feature of the candidate mark, resulting in a profile for that feature. The computing device filters out, from the feature profile, all spatial frequency components that are indicated to be sibling frequency components. In some embodiments, the computing device carries out the reverse procedure, and filters out all spatial frequency components except for those indicated to be sibling frequency components.

Abstract: Methods for determining whether a mark is genuine are described. According to various implementations, a computing device (or logic circuitry thereof) receives (e.g., via a camera or via a communication network) an image of a candidate mark (e.g., a one-dimensional or two-dimensional barcode), uses the image to make measurements of a characteristic of a feature of the candidate mark, resulting in a profile for that feature. The computing device filters out, from the feature profile, all spatial frequency components that are indicated to be sibling frequency components. In some embodiments, the computing device carries out the reverse procedure, and filters out all spatial frequency components except for those indicated to be sibling frequency components.

Abstract: According to various implementations, a computing device receives an image of a candidate mark and uses the image to create a profile of a feature of the mark. The computing device filters out, from the profile, all spatial frequency components except for a first band of spatial frequency components, resulting in a first filtered profile for the feature. The computing device repeats this filtering process for a second band of spatial frequency components, resulting in a second filtered profile for the feature, and may repeat this filtering process for further spatial frequency bands. The computing device compares the first filtered profile of the candidate mark with an equivalent first filtered profile of a genuine mark, and may repeat this process for further filtered profiles.