Abstract Multimodal biometrics, which consists of combining several biometrics systems. Indeed, it makes it possible to reduce certain unimodal biometric systems limitations, such as the impossibility of acquiring data from certain people or intentional fraud, while improving recognition performance. These benefits of multimodality to unimodal biometric systems are achieved by fusion of several biometric systems. In this case, the security is a necessity to have... Multimodal biometrics, which consists of combining several biometrics systems. Indeed, it makes it possible to reduce certain unimodal biometric systems limitations, such as the impossibility of acquiring data from certain people or intentional fraud, while improving recognition performance. These benefits of multimodality to unimodal biometric systems are achieved by fusion of several biometric systems. In this case, the security is a necessity to have robust and user-friendly biometric systems. In this paper, we proposed a Revocable multi biometric scheme to secured multi biometric data, we focused our attention on BioHashing method which is a recent technique that can address simultaneously the invasion of privacy issue and the Security. An improvement in the level of characteristics has been introduced to obtain very satisfactory results. It combines fingerprint multi sensor features of a single human finger. Read More Read Less

Abstract In this paper, we propose a new scheme for joint compression and encryption of digital images, based on cellular automata and selective encryption of quantized DCT coefficient. Using a key stream by a cellular automata mechanism, a subset of quantized coefficients is selected and then ciphered with the produced pseudorandom key-stream. Thus, we achieve a sufficiently robust security level, mostly against... In this paper, we propose a new scheme for joint compression and encryption of digital images, based on cellular automata and selective encryption of quantized DCT coefficient. Using a key stream by a cellular automata mechanism, a subset of quantized coefficients is selected and then ciphered with the produced pseudorandom key-stream. Thus, we achieve a sufficiently robust security level, mostly against known plaintext attacks while preserving a high compression ratio. Several performance analysis including security analysis, speed performances and compression ratio are performed, and demonstrate the efficacy of the proposed approach with respect to existing ones. Read More Read Less

Abstract A new method is proposed to detect sunspots on full-disk solar images recorded by Solar Diameter Imager and Surface Mapper (SODISM) on the PICARD satellite. The procedure of the method is totally automated to detect sunspots and compression with NOAA catalogue shows sunspot recognition rate is 97.8%. The number of sunspots detected by methods shows acquit good agreement with NOAA... A new method is proposed to detect sunspots on full-disk solar images recorded by Solar Diameter Imager and Surface Mapper (SODISM) on the PICARD satellite. The procedure of the method is totally automated to detect sunspots and compression with NOAA catalogue shows sunspot recognition rate is 97.8%. The number of sunspots detected by methods shows acquit good agreement with NOAA catalogue Furthermore, calculate the filling factor for W.L. 607nm and compared with SOHO satellite has been presented. The sunspot areas calculated by this method have a high correlation with SOHO in the same period it is 99%. Read More Read Less