Abstract—With a rapidly increasing incidence of melanoma

skin cancer, there is a need for decision support systems to

detect it in its early stages, which would lead to better decisions

in treating it successfully. However, developing such systems is

still a challenging task for researchers. Several Computer Aided-

Diagnosis (CAD) systems have been proposed in the last two

decades to increase the accuracy of melanoma detection. Image

feature extraction is a critical step in differentiating between

melanoma and normal skin lesions. In this paper, we propose

to improve a bag-of-words approach by combining features

consisting of the color histogram and first order moments with the

Histogram of Oriented Gradients (HOG). Experimental results

show that the proposed technique significantly improves the

detection accuracy, with an average sensitivity of 91% and

specificity of 85%. The proposed system was validated on a

dataset of 200 medically annotated images (40 melanomas and

160 non-melanomas) obtained from the database of the Hospital

Pedro Hispano. 

This paper presents a novel secure and robust steganographic technique in the compressed video domain namely embedding-based byte differencing (EBBD). Unlike most of the current video steganographic techniques which take into account only the intra frames for data embedding, the proposed EBBD technique aims to hide information in both intra and inter frames. The information is embedded into a compressed video by simultaneously manipulating the quantized AC coefficients (AC-QTCs) of luminance components of the frames during MPEG-2 encoding process. Later, during the decoding process, the embedded information can be detected and extracted completely. Furthermore, the EBBD basically deals with two security concepts: data encryption and data concealing. Hence, during the embedding process, secret data is encrypted using the simplified data encryption standard (S-DES) algorithm to provide better security to the implemented system. The security of the method lies in selecting candidate AC-QTCs within each non-overlapping 8 × 8 sub-block using a pseudo random key. Basic performance of this steganographic technique verified through experiments on various existing MPEG-2 encoded videos over a wide range of embedded payload rates. Overall, the experimental results verify the excellent performance of the proposed EBBD with a better trade-off in terms of imperceptibility and payload, as compared with previous techniques while at the same time ensuring minimal bitrate increase and negligible degradation of PSNR values.

Recent developments in both information and communication security have heightened interest in enhancing the embedding capacity for data handling techniques. Although many steganographic techniques, in the literature, have been developed for this purpose, most of them distort the quality of the host-signal during data embedding and the changes will be become visible to the human eye especially for those signals distributed via the Internet which must be processed by a low bit rate compression due to bandwidth limitations. Therefore, the challenge is to create a steganographic technique that is able to hide acceptable amount of data without altering the quality of the host-signal. In this paper, pixel-value differencing (PVD) steganographic scheme and its two modified versions, namely, enhanced pixel-value differencing (EPVD) and tri-way pixel-value differencing (TPVD) were implemented, analyzed and compared in terms of invisibility, fidelity and impact of data hiding on the compression efficiency. Experimental results indicate that the EPVD scheme is capable of providing better performance than other compared schemes.

Abstract Mel Frequency Cepstral Coefficients (MFCCs) are the most widely used features in the majority of the speaker and speech recognition applications. Since 1980s, remarkable efforts have been undertaken for the development of these features. Issues such as use suitable spectral estimation methods, design of effective filter banks, and the number of chosen features all play an important role in the performance and robustness of the speech recognition systems. This paper provides an overview of MFCC's enhancement techniques that are applied in speech recognition systems. The details such as accuracy, types of environments, the nature of data, and the number of features are investigated and summarized in the table combined with the corresponding key references. Benefits and drawbacks of these MFCC's enhancement techniques have been discussed. This study will hopefully contribute to raising …

Abstract— Diagnosing skin cancer in its early stages is a challenging task for dermatologists given the fact that the chance for a patient’s survival is higher and hence the process of analyzing skin images and making decisions should be time efficient. Therefore, diagnosing the disease using automated and computerized systems has nowadays become essential. This paper proposes an efficient system for skin cancer detection on dermoscopic images. It has been shown that the statistical characteristics of the pigment network, extracted from the dermoscopic image, could be used as efficient discriminating features for cancer detection. The proposed system has been assessed on a dataset of 200 dermoscopic images of the ‘Hospital Pedro Hispano’ [1] and the results of cross-validation have shown high detection accuracy.

With the rapid development of the Internet and communication networks, the confidentiality of digital

images transmitted over public networks must be preserved by using encryption techniques. Advanced

Encryption Standard (AES) is one of the most commonly used encryption algorithms at present. Although

AES has several advantages, such as security in data encryption, it also has a number of drawbacks, such as

high computations, pattern problems when used for encrypting images, and fixed S-box weak points. This

paper proposes a method that overcomes the fixed S-box weak points and improves the performance of

AES when used for encrypting images, particularly when the image data are large. In addition, the

MixColumn stage is replaced by chaotic mapping and XOR operation to reduce the high computations in

MixColumn transform. The proposed method is tested on several images, and the results show that the

proposed method efficiently generated cipher images with very low correlation coefficients of adjacent

pixels and provided better encryption speed and high security as a result of the dependence of the S-box on

the key characteristics of the chaotic system

Steganographic techniques with varying degrees of embedding capacity, perceptual transparency, and security are presented. These techniques have been developed to protect privileged or confidential information restricted to public access and to replace cryptography methods. In this study, three embedding algorithms, namely, least significant bit insertion, bit-plane complexity segmentation, and enhanced version of pixel value difference (EPVD) were implemented and analyzed in terms of the main steganography issues (payload, invisibility, and security) using a different proper performance metrics. This study was motivated by the minimal research focus accorded to hiding data in compression domain for the class of video-based embedding methods. Therefore, analyzing steganographic algorithms is generally based on hiding information in the quantized AC-Coefficients of the frames during the MPEG-2 compression process. Simulation results reveal that EPVD provides better embedded payload and acceptable visual quality, but lower PSNR value.

Most data-hiding techniques have already been investigated in detail as regards image files in both

the spatial and frequency domains. However, they are currently the subject of several investigations in

the video domain. In recent years, among many proposed steganographic methods in the spatial

domain, pixel-value differencing (PVD) provides both high embedding capacity and viable

imperceptibility for images compared with other techniques, such as least significant bit (LSB) method.

It utilizes the remainder of two consecutive pixels in embedding secret data, and the number of

embedded bits is based on the amount of difference. The large amount of difference indicates that more

secret bits can be embedded. However, based on extensive experiments, using such technique to embed

secret data in the frequency domain creates a massive negative effect on hosted data, even resulting in

low embedding capacity, which will lead to undesired distortion in the host file. In this paper, some

modifications to the PVD method are proposed that make it capable of embedding secret information

in macro-blocks of both I-frames and P-frames for MPEG-2 video during compression. The

modifications applied to PVD reduce the distortion drift caused by reversible data hiding within

selected macro-block coefficients. Furthermore, this research devises an adaptive method that can

achieve a more secure scheme for embedding data based on encrypting the host macro-block

coefficients before the hiding process using a secret encrypted key. Based on the simulation results

obtained in this proposed approach, the proposed scheme successfully improves the perceived quality

and achieves much better security compared with PVD-based method while still retaining the

advantage of hiding a large amount of information.

The aim was to build an educational website to teach preschoolers aged 2-5 years old some skills; related to reading, writing and pronouncing alphabet, numbers, animal names, shapes and other common words. Also, assist parents and teachers by providing digital game-based learning environment to “edutainment” the children. The study illustrated the usability and usefulness of this educational game-based website and provided future insights for researchers and developers to take into account in future work.

one of the challenges recently occurred in the concept of hiding data is the

robustness of hiding data in the way that is difficult to access or detect. Most of the steganography

schemes are based commonly on embed data within images or video frames on their original form

(uncompressed domain).

This paper presents a new methodology for data hiding in MPEG-2 video standard. Data will be

embedding during the compression stage of the AVI-MPEG2 encoding. The BPCS algorithm has

been modified and used in all our experiments for embed data, and the DES (Data Encryption

Standard) algorithm has been used to encrypt data before hiding. It only embeds encrypted data

bits in the quantized AC coefficients (low-frequency AC coefficients) of Y components (Luminance)

for the I-Frame. The obtained results demonstrate that the proposed method has the considerable

advantage over previous steganography schemes with a good PSNR values for the embedded