Nasharuddin Zainal

Fast and reliable iris segmentation algorithm

Design a fast and reliable iris segmentation algorithm for less constrained iris images is essential to build a robust iris recognition system. Daugmans integrodifferential operator (IDO) is one of powerful iris segmentation mechanisms, but in contrast consumes a large portion of the computational time for localising the rough position of the iris centre and eyelid boundaries. To address this problem, a fast iris segmentation algorithm is proposed. First, the circular Gabor filter is adopted to find the rough position of the pupil centre. Second, the iris and pupil circles are localised using the IDO taken into account that the real centres of the iris and pupil are in the small area around the rough position of the pupil centre. Third, the upper and lower eyelid boundaries are extracted using the live-wire technique. Experimental results demonstrate that the proposed iris segmentation algorithm significantly minimises the required time to segment the iris without affecting the segmentation accuracy. Moreover, the comparison results with state-of-the-art iris segmentation algorithms show the superiority of the proposed algorithm in terms of segmentation accuracy and recognition performance. The challenging UBIRIS.v1 iris image database is utilised to evaluate the performance of the proposed algorithm.

High Definition Image Encryption Algorithm Based on AES Modification

In this article, a high-speed and highly restricted encryption algorithm is proposed to cipher high-definition (HD) images based on the modified advanced encryption standard (AES) algorithm. AES is a well-known block cipher algorithm and has several advantages, such as high-level security and implementation ability. However, AES has some drawbacks, including high computation costs, pattern appearance, and high hardware requirements. The aforementioned problems become more complex when the AES algorithm ciphers an image, especially HD images. Three modifications are proposed in this paper to improve AES algorithm performance through, decreasing the computation costs, decreasing the hardware requirements, and increasing the security level. First, modification was conducted using MixColumn transformation in 5 rounds instead of 10 rounds in the original AES-128 to decrease the encryption time. Security is enhanced by improving the key schedule operation by adding MixColumn transformation to this operation as second modification. In addition, to decrease the hardware requirements, S-box and Inv. S-box in the original AES are replaced by one simple S-box used for encryption and decryption in the proposed method. The proposed AES version conducts one of the ciphering modes to solve the appearance pattern problem. Experimental results indicate that the proposed modifications to the AES algorithm made the algorithm more compatible with HD image encryption.

Automated segmentation of iris images acquired in an unconstrained environment using HOG-SVM and GrowCut

Abstract Iris recognition systems have demonstrated considerable improvement in recognizing people through their iris patterns. Recent iris recognition systems have focused on images acquired in unconstrained environments. Unconstrained imaging environments allow the capture of iris images at a distance, in motion and under visible wavelength illumination which lead to more noise factors such as off-focus, gaze deviation, and obstruction by eyelids, eyeglasses, hair, lighting and specular reflections. Segmenting irises taken in an unconstrained environment remains a challenging task for iris recognition. In this paper, a new iris segmentation method is developed and tested on UBIRIS.v2 and MICHE iris databases that reflect the challenges in recognition by unconstrained images. This method accurately localizes the iris by a model designed on the basis of the Histograms of Oriented Gradients (HOG) descriptor and Support Vector Machine (SVM), namely HOG-SVM. Based on this localization, iris texture is automatically extracted by means of a cellular automata which evolved via the GrowCut technique. Pre- and post-processing operations are also introduced to ensure higher segmentation accuracy. Extensive experimental results illustrate the effectiveness of the proposed method on unconstrained iris images.

Decomposition by binary codes-based speedy image encryption algorithm for multiple applications

The rapid growth in the use of multimedia information has made the security of data storage and transmission important in avoiding unlawful, unofficial, unauthorised and illegal use. Encryption is an efficient operation to protect multimedia data secret. A new image encryption approach that uses binary coded decimal (BCD) code-based decomposition, reordering and scrambling bit planes, and an encryption process is suggested in this study. Image decomposition using BCD code for image encryption is introduced in this study. A simple scrambling process is used to shuffle binary bit planes after re-ordering them. A shift column operation is applied to the image that is constructed after scrambling the bit planes to increase the security level. A performance analysis and a comparison with other encryption algorithms are conducted to prove the proposed algorithms image encryption capabilities. The experimental results show that the suggested method protects secret images against common attacks with shorter encryption/decryption times.

A static and dynamic visual debugger for malware analysis

The number of viruses and malware has grown dramatically over the last few years, and this number is expected to grow in all likelihood. Due to the increasing amount of malicious software circulated over the Internet, it is almost impossible to reverse engineering all binary executable software line by line as it is very challenging and time consuming. In order to provide immediate security solutions and reduce the amount of time on understanding malicious portion consisted in viruses, Trojans and other general security flow, a comprehensive design of visual debugger is introduced in this paper. The research involves with the reverse engineering of binary executable by transforming a stream of bytes that constitutes the program into a corresponding sequence of machine instructions. Both static and dynamic debugger will be developed and interacted with a graph visualization system to visualize the parse instructions of a targeted executable file in execution flow graph. With the intention of improving the effectiveness, graph visualization is developed to accelerate the analysis progress. We reconstruct the targeted programs control flow and broke it into smaller regions. Fragment of malicious instructions can be easily determined via the control flow graph information.

Iris Segmentation: A Review and Research Issues

In recent years, due to the crime spreading and the potential of security threats, a lot of efforts have been spent to develop a reliable surveillance system. Biometric systems have grown in popularity as a trustworthy way to authenticate the identity of individuals. There are several biometrics to identify the persons such as Fingerprint, Face, Iris, Ear and Gait. The iris biometric is considered the best biometrics, due to its speed and accuracy in the identification, and distinctive features along the individual’s lifetime. This paper focuses on issues of the iris segmentation research in the existing techniques. The techniques reported here can be categorized based on image acquisition environment into two scenarios: close-up imaging settings and non-cooperative imaging settings. The theorem behind each strategy is presented along with the outlines of implementation. A review of the issues in the iris segmentation methods coupled with comparison to the relevant issues is included. The weakness of each method is also obtained.

Voice quality in speech watermarking using spread spectrum technique

One of the important problems in communication is sending specific data privately. In addition to cryptography which was used many years ago, methods such as data hiding have been introduced in recent years. In data hiding, specific data is embedded in another signal, which is known as a host signal that can be in the form of video, image and audio. Because of narrow bandwidth limitation, speech signal is seldom used, despite its popularity in communication application such as military, bank phone and network security. A data hiding algorithm in speech signal is called speech watermarking. Watermarking will be more robust against attacks (i.e. watermark removal and impairment attacks) with uses the Spread Spectrum technique. Speech watermarking is implemented using simulation and then been evaluated based on the quality of voice (speech) by the Mean Opinion Score (MOS) from 20 respondents. The average MOS is 2.75 out of 5 showings between fair and poor perceptual audibility quality.

Location-aided scanning mechanism using GPS during handoff process in mobile WiMAX

In order to support mobility which guarantees an uninterrupted service, handoff is one of the crucial criteria to be concerned about, especially on latency during handoff, that might interrupt the on-going services. This is due to the redundant and inappropriate scanning producing delay as well as packet loss during the handover process. An enhancement of scanning technique with location-aided path database is introduced to reduce delay during scanning. The proposed mechanism reduces scanning time by reducing the number of Base Station (BS) to be scan using GPS (Global Positioning System) as location-aid. The scheme is expected to short-list the potential Base Station according to the location of the Mobile Station (MS) and the path chosen. Simulation result shows that by using proposed method, average scanning time is shorter than the average scanning time in the conventional method.

Audio-Speech Watermarking Using a Channel Equalizer

AbstractCurrently, the use of telephone systems is highly popular in speech telecommunication and also they have a wide presence in transmission of digital signals. In recent years, audio-speech watermarking as a modern technique makes use of the telephone channel to transmit the watermark data, but addressing the watermark’s vulnerability to noise in the telephone channel is a difficult problem in digital audio-speech watermarking. This paper presents a robust audio-speech watermarking scheme that operates against channel noise according to audio-speech specifications, the channel coding and channel equalizer technique. The proposed scheme is based on the spread spectrum technique and a psychoacoustic model with use of the channel equalizer to remove or minimize the effects of channel noise over the watermark signal. The simulation results for imperceptibility of the watermark, voice quality, and robustness against channel noise are presented in this study. The results indicate that the proposed scheme is highly satisfactory for the cases mentioned above.

Fast, accurate and memory efficient pupil localization based on pixels properties method

One of the most crucial processes in the iris recognition system is iris segmentation. In iris segmentation, the iris region is extracted from the eyelids, eyelashes, eyebrows, pupil and sclera to identify the uniqueness of its patterns. The segmentation process is crucial since the poor and false segmentation can affect the accuracy of the iris recognition system. Since the system will deal with a lot of irises, it must be fast enough to execute the iris segmentation. The speed also crucial in order to implement it in real-time. Pupil localization is a part of iris segmentation process which is to locate pupil boundaries. The pupil boundaries can provide the information of pupil center and radius as a based to locate the iris boundaries. This research is important since poor pupil localization due to reflections and eyelashes interferences can reduce the segmentation accuracy of the iris recognition system. Moreover, the modified segmentation methods based on Hough transform and Integro-differential operator are still complex and require a lot of time. Furthermore, there are many pupil and iris localization methods that assume the shape of pupil as a circle which is not accurate. In this paper, the new pupil localization method which is based on pixels properties is proposed to obtain fast, accurate and memory efficient of pupil localization in the iris recognition system. The proposed method is compared with other methods based on localization accuracy, time to execute and memory usage. According to the results, the proposed method recorded high localization accuracy, low execution time and low memory usage than the other state-of-the-art methods. This proves that the proposed pupil localization method is appropriate and suitable to be implemented in real-time systems.