摘要:
Methods and devices of studying a predefined portion of an object having a feature of interest are disclosed. The feature of interest defines a class of objects that includes the object. Light sources directly illuminate the object from different illumination directions. The light sources are maintained in a stable configuration relative to the object. For each illumination direction, an image is generated from light scattered from the object with a camera maintained in a stable configuration relative to the light sources. A methodology derived from machine learning for the class of objects is applied to filter the generated images are filtered for a characteristic consistent with the fetaure of interest. Surface gradients are determined from the filtered images and integrated to generate a topography of a surface of the object.
摘要:
Methods are disclosed for transmitting information from a handheld device to a terminal. The information is encoded as a barcode pattern. The barcode pattern is generated on a display of the handheld device. A size of the barcode pattern is periodically modulated on the display while maintaining internal relative dimensions within the barcode pattern. The periodically modulating barcode pattern is displayed to an optical reader of the terminal.
摘要:
A variety of forms of machine-readable symbols are disclosed, as well as methods and systems of constructing machine-readable symbols, methods and systems of acquiring machine-readable symbols, and methods and systems of decoding machine-readable symbols.
摘要:
Methods and apparatus are provided of deriving a discrimination feature set for use in identifying biometric spoofs. True skin sites are illuminated under distinct optical conditions and light reflected from each of the true skin sites is received. True-skin feature values are derived to characterize the true skin sites. Biometric spoofs is similarly illuminated under the distinct optical conditions and light reflected from the spoofs is received. Spoof feature values are derived to characterize the biometric spoofs. The derived true-skin feature values are compared with the derived spoof feature values to select a subset of the features to define the discrimination feature set.
摘要:
Methods are described of evaluating the genuineness of a sample presented for biometric evaluation. The sample is illuminated under distinct optical conditions. Light scattered from the sample is received. Multiple images are formed, each image being formed from the received light for one of the optical conditions. A set of texture measures is generated, each texture measure being generated from one of the images. It is determined whether the generated texture measures is consistent with the sample being authentic unconcealed biological tissue.
摘要:
Methods and systems are provided for performing a biometric function. A purported skin site of an individual is illuminated under distinct optical conditions during a single illumination session for a fixed position of the purported skin site. Light from the purported skin site is received for each of the optical conditions. Images of the purported skin site are generated from the received light. The images are analyzed to identify a biometric feature as a characteristic in a portion of at least one of the images. The biometric function is implemented in accordance with an identification of the biometric feature.
摘要:
Methods and apparatus for non-invasively verifying human identities using near-infrared spectroscopy. Near-infrared tissue spectra can be obtained by projecting near-infrared radiation into skin on the underside of human forearms and capturing the light reflected back and out through the tissue. The tissue spectrum collected preferably includes primarily diffuse reflected light reflected from the inner dermis. Multiple tissue spectra and identities can be collected from individuals for whom identity verification may later be desired. The tissue spectra for each individual can be analyzed on a computer, and the spectra for each individual clustered or classified together using tools such as linear discriminant analysis. A target individual seeking identity verification can submit both a purported identity and a near-infrared tissue spectrum for analysis through near-infrared spectroscopy of the forearm. Similarity between the target spectrum and the multiple spectra for the purported identity in the spectral database is determined and identify verified or not verified based on the degree of similarity.
摘要:
Methods and apparatus for performing biometric identification or verification of identities using optical spectroscopy of tissue. Tissue optical spectra can be obtained by projecting optical radiation into skin and capturing the light transmitted or reflected back and out through the tissue. The tissue spectra collected preferably includes primarily light that has passed through skin tissue below the epidermis. Multiple tissue spectra and identities can be collected from one or more individuals. These tissue spectra can be analyzed on a computer, and the spectral features that are most important for classifying person-to-person differences can be established using principle component analysis, linear discriminant analysis, or a variety of other related techniques. One or more tissue spectra and identities can be collected from individuals for whom identification or verification may later be desired. A target individual seeking identification or verification can submit a suitable tissue site for spectroscopic measurement. In addition a target individual seeking identity verification can submit a purported identity using some means such as a typed user name, PIN code, magnetic card, transponder, etc. Similarity between the target spectrum and the spectrum or spectra in the enrolled spectral database with respect to the inter-person classification spectral features is determined and identification or verification is granted based on the degree of similarity.
摘要:
A method and apparatus for non-invasively measuring a biological attribute, such as the concentration of an analyte, particularly a blood analyte in tissue such as glucose. The method utilizes spectrographic techniques in conjunction with an improved subject-tailored calibration model. In a calibration phase, calibration model data is modified to reduce or eliminate subject-specific attributes, resulting in a calibration data set modeling within- subject physiological variation, sample location, insertion variations, and instrument variation. In a prediction phase, the prediction process is tailored for each target subject separately using a minimal number of spectral measurements from each subject.
摘要:
A method and apparatus for non-invasively measuring a biological attribute, such as the concentration of an analyte, particularly a blood analyte in tissue such as glucose. The method utilizes spectrographic techniques in conjunction with an improved subject-tailored calibration model. In a calibration phase, calibration model data is modified to reduce or eliminate subject-specific attributes, resulting in a calibration data set modeling within--subject physiological variation, sample location, insertion variations, and instrument variation. In a prediction phase, the prediction process is tailored for each target subject separately using a minimal number of spectral measurements from each subject.