1,721,044 research outputs found
Biometric recognition through 3D ultrasound hand geometry
No full textBiometric recognition systems based on ultrasonic images have several advantages over other technologies, including the capability of capturing 3D images and detecting liveness. In this work, a recognition system based on hand geometry achieved through ultrasound images is proposed and experimentally evaluated. 3D images of human hand are acquired by performing parallel mechanical scans with a commercial ultrasound probe. Several 2D images are then extracted at increasing under-skin depths and, from each of them, up to 26 distances among key points of the hand are defined and computed to achieve a 2D template. A 3D template is then obtained by combining in several ways 2D templates of two or more images. A preliminary evaluation of the system is achieved by carrying out verification experiments on a home–made database. Results have shown a good recognition accuracy: the Equal Error Rate was 1.15% when a single 2D image is used and improved to 0.98% by using the 3D template. The possibility to upgrade the proposed system to a multimodal system, by extracting from the same volume other features like palmprint and hand veins, as well as possible improvements are finally discussed
Optimization and evaluation of a biometric recognition technique based on 3D Ultrasound Palm Vein
No full textBiometric systems based on ultrasound images are becoming more and more common and are exploiting different characteristics like fingerprint, palmprint, hand geometry and palm vein patterns. In this work, a previously proposed method for extracting 3D palm vein patterns from volumetric ultrasound images has been optimized and experimentally evaluated by using a home-made database composed on 55 volumetric images captured from 23 different volunteers. If compared with recent works, recognition results seems encouraging. Further possible improvements of the proposed technique are finally discussed
Ultrasound Systems for Biometric Recognition
No full textBiometric recognition systems are finding applications in more and more civilian fields because they proved to be reliable and accurate. Among the other technologies, ultrasound has the main merit of acquiring 3D images, which allows it to provide more distinctive features and gives it a high resistance to spoof attacks. This work reviews main research activities devoted to the study and development of ultrasound sensors and systems for biometric recognition purposes. Several transducer technologies and different ultrasound techniques have been experimented on for imaging biometric characteristics like fingerprints, hand vein pattern, palmprint, and hand geometry. In the paper, basic concepts on ultrasound imaging techniques and technologies are briefly recalled and, subsequently, research studies are classified according to the kind of technique used for collecting the ultrasound image. Overall, the overview demonstrates that ultrasound may compete with other technologies in the expanding market of biometrics, as the different commercial fingerprint sensors integrated in portable electronic devices like smartphones or tablets demonstrate
Aspect ratio optimization of piezoceramic disks for maximizing electromechanical energy conversion in energy harvesting applications
No full textA wide variety of devices based on piezoceramic elements, vibrating in several modes, have been proposed and developed for energy harvesting applications. The evaluation of the capability of converting mechanical energy into electric energy is a main issue in the device design. In this work, the dependence of the piezoceramic element performances on the aspect ratio, i.e., the ratio between thickness and diameter, is analyzed with the aim of maximizing the energy conversion. To the end, the effective electromechanic coupling factor (keff), which is a parameter that can be easily measured, is the investigated parameter. Results obtained with analytical and FE models have shown that the higher keff value is obtained when the thickness and the diameter of the piezoceramic element are comparable. A first experimental validation of simulation results is finally provided
3D Vascular Pattern Extraction from Grayscale Volumetric Ultrasound Images for Biometric Recognition Purposes
Full text linkRecognition systems based on palm veins are gaining increasing attention as they are highly distinctive and very hard to counterfeit. Most popular systems are based on infrared radiation; they have the merit to be contactless but can provide only 2D patterns. Conversely, 3D patterns can be achieved with Doppler or photoacoustic methods, but these approaches require too long of an acquisition time. In this work, a method for extracting 3D vascular patterns from conventional grayscale volumetric images of the human hand, which can be collected in a short time, is proposed for the first time. It is based on the detection of low-brightness areas in B-mode images. Centroids of these areas in successive B-mode images are then linked through a minimum distance criterion. Preliminary verification and identification results, carried out on a database previously established for extracting 3D palmprint features, demonstrated good recognition performances: EER = 2%, ROC AUC = 99.92%, and an identification rate of 100%. As further merit, 3D vein pattern features can be fused to 3D palmprint features to implement a costless multimodal recognition system
Fusion Analysis of a Palmprint-Hand Geometry Multimodal Ultrasound Recognition System
No full textMultimodal biometric systems are employed in several application fields due to series of advantages in terms of universality and recognition rate. Compared to other technologies, Ultrasound has many advantages, because it allows to obtain 3D images of human body and to verify liveness. In this work, a multimodal ultrasound recognition system based on the fusion of palmprint and hand geometry is proposed and experimentally evaluated. Volumetric hand images are acquired by using water as coupling medium and 2D rendering are obtained at various depth levels. Successively, 2D and 3D features are extracted both for palmprint and hand-geometry. Recognition performances are evaluated through verification experiments by employing a homemade database, first by considering the single characteristics and successively by fusing them. Results demonstrated a drastic improving of results with the fusion but not necessarily the best fusion result is obtained by considering the best palmprint and hand geometry
Multimodal Biometric Recognition Based on 3D Ultrasound Palmprint-Hand Geometry Fusion
Full text linkIn recent years, multimodal biometric systems are increasingly employed in many application field due to several advantages in terms of universality, recognition rate. and security. Among various acquisition technologies, Ultrasound shows important merits, because it allows obtaining volumetric images of the human body and hence a more accurate description of characteristics and to verify liveness. In this work, a multimodal ultrasound recognition system based on the fusion between 3D hand geometry and 3D palmprint features is proposed and experimentally evaluated. The system acquires a volumetric image of the whole hand and for both characteristics, several 2D images are extracted at different depth levels. From each image, 2D features are extracted and then properly combined to achieve a 3D template. Recognition performances are evaluated through verification and identification experiments by employing a homemade database. Experiments are carried out first for the two unimodal biometrics and successively, by fusing the two modalities at score level. Results have shown that fusion is able to dramatically improve the recognition performances of the single biometrics, achieving an Equal Error Rate of 0.08% and an identification rate of 100%
A Feasible 3D Ultrasound Palmprint Recognition System for Secure Access Control Applications
Full text linkBiometric recognition systems based on 3D palmprint captured with optical technology have been widely investigated in the last decade; however, they can provide information about the external skin surface only. This limit can be overcome by Ultrasound, which allows gaining information on the depth of palm lines and can verify the liveness of the sample, making the recognition systems very hard to fake. In this work, a feasible palmprint recognition system based on 3D ultrasound images is proposed. Unlike previous wet setups, the coupling between probe and human is realized through a gel pad, which permits a comfortable and precise positioning of the hand by the user. Collected 3D images are processed to generate 2D palmprint images at various under-skin depths. 2D features are then extracted from these images, experimenting with different procedures, and are merged to define a 3D template that contains lines' depth information. Recognition performances were evaluated by performing verification and identification experiments on a home-made database composed of 423 samples from 55 volunteers. An EER rate of 0.36% and an identification accuracy of 100% are obtained. The suitability of the proposed system in secure access control applications is finally discussed
Experimental evaluation of an ultrasound technique for the biometric recognition of human hand anatomic elements
No full textAn ultrasound technique for 3D palmprint extraction
No full textIn this work, an ultrasound technique for extracting 3D palmprints is experimentally evaluated. A commercial ultrasound imaging machine, provided with a high frequency (12 MHz) linear array, is employed for the experiments. The probe is moved in the elevation direction by a motorized stepper stage and a teach step a B-scan is acquired and stored to form a 3D matrix representing the under skin volume. The data from the 3D matrix are elaborated to provide several renderings of the 3D ultrasonic palmprint. The results have been compared with corresponding samples obtained with conventional methods and the advantages of the ultrasound technique are underlined and discussed
- …
