Статьи журнала - International Journal of Image, Graphics and Signal Processing
Все статьи: 1056
Статья научная
Nowadays, the ground radar systems are mostly used for controlling airspace or making weather images. These systems consist of large antenna, a lot of the electronic equipment and very powerful computational unit. Smaller versions of these systems are often carried on the board of planes but still they are quite complex devices. Much simpler versions of the systems mentioned above but still using the same basic principles are small compact devices for measuring Target RCS or Target detection. In these applications, small size embedded SDR radar can be used. Then real time processing of a radar signal can also be much simpler. For the above mentioned simple applications, it is possible and reasonable to have small devices with low power consumption that perform real time correlation based processing. Typical today's embedded FPGA based SDR solutions have enough computational performance and their electric input is also very low. Moreover, the dimensions of the processor boards are very compact and they can be easily integrated into very small cases. That's why it is good to transfer radar signal processing algorithms to the embedded system. The recent development in the digital Radar is now molded in these SDR systems. Our motivation is to design a Spread Spectrum based digital SDR radar which is very small in size and may be a low cost solution where we can bypass all the huge instrumentation complexity. This type of solution is now popular for defense organizations, even can be used in human daily life.
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Emotion Recognition System of Noisy Speech in Real World Environment
Статья научная
Speech is one of the most natural and fundamental means of human computer interaction and the state of human emotion is important in various domains. The recognition of human emotion is become essential in real world application, but speed signal is interrupted with various noises from the real world environments and the recognition performance is reduced by these additional signals of noise and emotion. Therefore this paper focuses to develop emotion recognition system for the noisy signal in the real world environment. Minimum Mean Square Error, MMSE is used as the enhancement technique, Mel-frequency Cepstrum Coefficients (MFCC) features are extracted from the speech signals and the state of the arts classifiers used to recognize the emotional state of the signals. To show the robustness of the proposed system, the experimental results are carried out by using the standard speech emotion database, IEMOCAP, under various SNRs level from 0db to 15db of real world background noise. The results are evaluated for seven emotions and the comparisons are prepared and discussed for various classifiers and for various emotions. The results indicate which classifier is the best for which emotion to facilitate in real world environment, especially in noisiest condition like in sport event.
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Emotion Recognition from Faces Using Effective Features Extraction Method
Статья научная
With the rapid development and requirement of application with Artificial Intelligent (AI) technologies, the researches related to human-computer interaction are always active and the emotional status of the users is very essential for most of the environment. Facial Emotion Recognition, FER is one of the important visual information providers for the AI systems. This paper proposes a FER system using an effective feature extraction methodology and classification technologies. Local features of the face are more effective features for recognition and Scale Invariant Feature Transform, SIFT can give a better representation of the face. The bag of the visual word (BOVW) is the good encoding method and the advancement of that model Vector of Locally Aggregate Descriptor, VLAD provides the better encoder for SIFT features and used these benefits for feature extraction environments. The power of SVM includes unknown class recognition problems and this advantage is used for classification. This system used the standard basement JAFEE dataset to measure the success of the proposed methods and prepared to compare with other systems. The proposed system achieves the better result when it compared with some of the other previous systems because of the combination of effective feature extraction and encoding method.
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Emotion recognition method using entropy analysis of EEG signals
Статья научная
This paper proposes an emotion recognition system using EEG signals, therefore a new approach to emotion state analysis by approximate (ApEn) and wavelet entropy (WE) is described. We have used EEG signals recorded during emotion in five channels (FP1, FP2, T3, T4 and Pz), under pictures induction environment (calm-neutral and negative excited) for participants. After a brief introduction to the concept, the ApEn and WE were extracted from two different EEG time series. The result showed that, the classification accuracy in two emotion states was 73.25% using the support vector machine (SVM) classifier. The simulations showed that the classification accuracy is good and the proposed methods are effective. During an emotion, the EEG is less complex compared to the normal, indicating reduction in active neuronal process in the brain.
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Статья научная
Today, rain remains one key and well-known natural phenomenon that offsets and attenuates the propagated radio, microwave, and millimeter-wave signals at different transmission frequencies and wavelengths over propagation paths. Specialised rain attenuation studies can be utilized to analyze their stochastic behavior on propagated radio signals and also come up with appropriate rain attenuation model for network application planning and optimisations. In this contribution, empirical rainfall depths data has been acquired, effectively categorized, and employed to examine the implicative intensity level trends over a ten years period, starting from 2011 to 2020. More importantly, the Recommendation ITU-R P.1511 power-based model combined with the acquired categorized rainfall depths data has been explored to prognostically estimate and quantity the amount of specific attenuation loss due over 3.5G transmission frequency. The results reveal that the level of attenuation attained versus 0.01% percentage of time depends on the type of rain intensity levels (heavy rain, very heavy rain, extremely heavy rain), which in turn is dependent upon rain depth or rate drop sizes. As a case in point, 0.001 percent of the time due to heavy rain, the amount of specific attenuation attained stood at 2dB, while for very heavy and extremely heavy rain, the specific attenuation levels amount to 2.3dB and 4dB respectively. These different amounts of specific attenuation simplify imply that the heavier the rain, the more scattering, and absorption the propagated electromagnetic signals undergo, thus leading to degraded and higher attenuation levels. The empirical based-rain attenuation quantification and impact analysis method explored in this paper will significantly provide radio network engineers with the best way to monitor and evaluate the radio attenuation effect over a propagation channel.
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Energy and Region based Detection and Segmentation of Breast Cancer Mammographic Images
Статья научная
Telemedicine is growing and there is an increased demand for faster image processing and transmitting diagnostic medical images. A region is a popular technique for image segmentation. We introduce a new approach that overcomes the close boundary initialization problem by reformulating the external energy term. We treat the contour as a mean curve of the probability density function. A widely used approach to image segmentation is to define corresponding segmentation energies and to compute shapes that are minimizes of these energies. In many medical image segmentation applications identifying and extracting the region of interest (ROI) accurately is an important step .We present a new image segmentation process, which can segment images with different image intensity distributions efficiently. To accomplish this, we construct a function that is evaluated along the evolving curve. In this cost, the value at each point on the curve is based on the analysis of interior and exterior means in a local neighborhood around that point.
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Enhanced Image Watermarking Technique using Wavelets and Interpolation
Статья научная
Image provides complete detailed information for thing or object. It is considered as an important aspect of analyzing the details of various objects or environments of real life applications. From analyzing or studying images, various techniques come into existence. These include zooming, watermarking, hazing, and compression. Each has its own advantages and disadvantages with respect to various implicit functions defined for the techniques. The research paper focuses on watermarking techniques. The techniques of watermarking have their advantages and outperforms better when combined with wavelets transformations (DWT) followed by interpolations. The wavelets and interpolations provide a good quality enhanced and zoomed watermarked images at the time of its encoding and decoding processes. The images are embedded with sample images considered as hidden information. After the extraction process image interpolation method is applied to the image to get a quality image. The process is suggested in order to view the changed pixels of images after encoding of two images. The combination of DWT watermarking and interpolation provides 52% better results when compared to existing techniques.
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Enhanced Performance of Multi Class Classification of Anonymous Noisy Images
Статья научная
An important constituents for image classification is the identification of significant characterstics about the specific class to distinguish intra class variations. Since performance of the classifiers is affected in the presence of noise, so selection of discriminative features is an important phase in classification. This superfluous information i.e. noise, e.g. additive noise may occur in images due to image sensors i.e. of the constant noise level in dark areas of the image or salt & pepper noise may be caused by analog to digitals conversion and bit error transmission etc.. Detection of noise is also very essential in the images for choosing appropriate filter. This paper presents an experimental assessment of neural classifier in terms of classification accuracy under three different constraints of images without noise, in presence of unknown noise and after elimination of noise.
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Enhancement of Hyperspectral Real World Images Using Hybrid Domain Approach
Статья научная
This paper presents enhancement of hyperspectral real world images using hybrid domain approach. The proposed method consists of three phases: In first phase the discrete wavelet transform is applied and approximation coefficient is selected. In second phase approximation coefficient of discrete wavelet transform of image is process by automatic contrast adjustment technique and in third phase it takes logarithmic of output of second phase and after that adaptive filtering is applied for image enhancement in frequency domain. To judge the superiority of proposed method the image quality parameters such as measure of enhancement (EME) and measure of enhancement factor (EMF) is evaluated. Therefore, a better value of EME and EMF implies that the visual quality of the enhanced image is good. Simulation results indicates that proposed method provides better results as compared to other state-of-art contrast enhancement algorithms for hyperspectral real world images. The proposed method is efficient and very effective method for contrast enhancement of hyperspectral real world images. This method can also be used in different applications where images are suffering from different contrast problems.
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Enhancement of Mammographic Images Based on Wavelet Denoise and Morphological Contrast Enhancement
Статья научная
Breast cancer can be detected by mammograms, but not all of them are of high enough quality to be diagnosed by physicians or radiologists. Therefore, denoising and contrast enhancement in the image are issues that need to be addressed. There are numerous techniques to reduce noise and enhance contrast; the most popular of which incorporate spatial filters and histogram equalization. However, these techniques occasionally result in image blurring, particularly around the edges. The purpose of this article is to propose a technique that uses wavelet denoising in conjunction with top-hat and bottom-hat morphological transforms in the wavelet domain to reduce noise and image quality without distorting the image. Use five wavelet functions to test the proposed method: Haar, Daubechies (db3), Coiflet (coif3), Symlet (sym3), and Biorthogonal (bior1.3); each wavelet function employs levels 1 through 4 with four types of wavelet shrinkage: Bayer, Visu, SURE, and Normal. Three flat structuring elements in the shapes of a disk, a square, and a diamond with sizes 2, 5, 10, 15, 20, and 30 are utilized for top-hat and bottom-hat morphological transforms. To determine optimal parameters, the proposed method is applied to mdb001 mammogram (mini MIAS database) contaminated with Gaussian noise with SD, = 20. Based on the quality assessment quantities, the Symlet wavelet (sym3) at level 3, with Visu shrinkage and diamond structuring element size 5 produced the best results (MSE = 50.020, PSNR = 31.140, SSIM = 0.407, and SC = 1.008). The results demonstrate the efficacy of the proposed method.
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Enhancing Colors of a Digital Image Using Clock Algorithm
Статья научная
Several commercial algorithms have been developed for color enhancement of a digital image; however, none of these are completely able to preciously process a digital image. Therefore, this article focuses upon pixel-by-pixel processing, especially in the field of color enhancement of digital image. The enhancement is performed on individual pixel by taking information from its neighborhood. This has been implemented using a clock algorithm. Clock algorithm enhancement is implemented on human visual system based hexagonal sampled pixels instead of square ones. Enhancement of each pixel is performed both locally and globally. The local enhancement is done by using wavelet normalization. It obtains different bands of information as it enables localizing the signal information both in time and frequency domain. The global enhancement is obtained through Gabor filter. The Gabor filter extracts region based information and combined information is used to recognize region of interest also Gabor filter justifies biological findings in vision system. The results after enhancement provide better visibility of minor information and finally the enhanced image is obtained.
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Enhancing Face Recognition Performance using Triplet Half Band Wavelet Filter Bank
Статья научная
Face recognition using subspace methods are quite popular in research community. This paper proposes an efficient face recognition method based on the application of recently developed triplet half band wavelet filter bank (TWFB) as pre-processing step to further enhance the performance of well known linear and nonlinear subspace methods such as principle component analysis(PCA),kernel principle component analysis (KPCA), linear discriminant analysis (LDA), and kernel discriminant analysis (KDA). The design of 6th order TWFB is used as the multiresolution analysis tool to perform the 2-D discrete wavelet transform (DWT). Experimental results are performed on two standard databases ORL and Yale. Comparative results are obtained in terms of verification performance parameters such as false acceptance rate (FAR), false rejection rate (FRR) and genuine acceptance rate (GAR). Application of TWFB enhances the performance of PCA, KPCA, LDA, and KDA based methods.
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Enhancing Lte Rss for a Robust Path Loss Analysis with Noise Removal
Статья научная
Wavelet transform has become a popular tool for signal denoising due to its ability to analyze signals effectively in both time and frequency domains. This is important because the information that is not visible in the time domain can be seen in the frequency domain. However, there are many wavelet families and thresholding techniques (such as haar, Daubechies, symlets, coiflets, meyer Gaussian, morlet, etc) thatare available for the analysis of signals, and choosing the best out of them all is usually time-consuming, thus making it a difficult task for researchers. In this article, we proposed and applied a stepwise expository-based approach to identify the wavelet family and thresholding technique using real-time signal power data acquired from Long-Term Evolution (LTE). We found out from the results that Rigrsure thresholding with the Daubenchies family outperforms others when engaged in practical signal processing. The stepwise expository-based approach will be a relevant guide to effective signal processing over cellular networks, globally. For validation, different datasets were used for the analysis and Rigrsure outperforms the other thresholding techniques.
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Статья научная
Nowadays in the digital world, there are lots of videos being uploaded to video, and social media sharing platforms are growing exponentially. About the Internet and multimedia technologies, illicitly copied content is a serious social problem. Since the internet is accessible to everyone, it is easy to download content and re-upload it. Copying videos from the internet can be considered plagiarism. In this paper, a method is proposed for feature extraction of video plagiarism detection. This framework is based on the local features to identify the videos frame by frame with the videos stored in the database. It becomes important to review the existing video plagiarism detection methods, compare them through appropriate performance metrics, list out their pros and cons and state the open challenges. First of all, it will pre-process the data with the help of SIFT and OCR Feature extraction. After that, the system applies the video retrieval and detection function using the two classifier algorithm the SVM, and the KNN. In the first stage, when the query is compared to all training data, KNN calculates the distances between the query and its neighbors and selects the K nearest neighbors. It is applied in the second stage to recognize the object using the SVM algorithm. Here we use the VSD dataset to predict the plagiarized videos. And the accuracy of these plagiarized videos after comparing them is 98%.
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Enhancing Security of Medical Image Data in the Cloud Using Machine Learning Technique
Статья научная
To prevent medical data leakage to third parties, algorithm developers have enhanced and modified existing models and tightened the cloud security through complex processes. This research utilizes PlayFair and K-Means clustering algorithm as double-level encryption/ decryption technique with ArnoldCat maps towards securing the medical images in cloud. K-Means is used for segmenting images into pixels and auto-encoders to remove noise (de-noising); the Random Forest regressor, tree-method based ensemble model is used for classification. The study obtained CT scan-images as datasets from ‘Kaggle’ and classifies the images into ‘Non-Covid’ and ‘Covid’ categories. The software utilized is Jupyter-Notebook, in Python. PSNR with MSE evaluation metrics is done using Python. Through testing-and-training datasets, lower MSE score (‘0’) and higher PSNR score (60%) were obtained, stating that, the developed decryption/ encryption model is a good fit that enhances cloud security to preserve digital medical images.
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Enhancing the Quality of Medical Images Containing Blur Combined with Noise Pair
Статья научная
In many fields, images become a useful tool containing data of which medical image is an example. The diagnosis depends on the skills of the doctors and image clarity. In the real world, most of medical images consist of noise and blur. This problem reduces the quality of images and causes difficulties for doctors. Most of the tasks of increasing the quality of medical images are deblurring or denoising process. This is the difficult problem in medical image processing, because it must keep the edge features and avoid the loss of information. In case of a medical image which contains noise combined with blur, it is more difficult. In this paper, we have proposed a method for increasing the quality of medical images in case that blur combined with noise pair is available in medical images. The proposed method is divided into two steps: denoising and deblurring. We use curvelet transform combined with bayesian thresholding for the denoising step and use the augmented lagrangian method for the deblurring step. For demonstrating the superiority of the proposed method, we have compared the results with the other recent methods available in literature.
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Статья научная
This paper presents a forensic perspective way of recognizing the weapons by processing wound patterns using ensemble learning that gives an effective forensic computational approach for the distinguished weapons used in most of crime cases. This will be one of the computational and effective substitutes to investigate the weapons used in crime, the methodology uses the collective wound patterns images from the human body for the recognition. The ensemble learning used in this proposed methodology improves the accuracy of machine learning methods by combining several methods and predicting the final accuracy by meta-classifier. It has given better recognition process compared to single individual model and the traditional method. Ensemble learning is more flexible in function and is better in the wound pattern recognition and their respective weapons as it overcomes the issue to overfit training data. The result achieved for weapon recognition based on wound patterns is 98.34%, from existing database of 800 images of pattern consisting of wounds of stabbed and gunshots. The authenticated experiments out-turns the preeminence of projected method over the widespread feature extraction approach considered in the work and also compares and suggest the false positive recognition verses false negative recognition. The proposed methodology has given better results compared to traditional method and will be helpful in forensic and crime investigation.
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Ergodic Matrix and Hybrid-key Based Image Cryptosystem
Статья научная
The existing traditional cryptosystems, such as RSA, DES, IDEA, SAFER and FEAL, are not ideal for image encryption because of their slow speed and ineffectiveness in removing the correlations of the adjacent pixels. Meanwhile chaos-based cryptosystems, which have been extensively used over the past two decades, are almost all based on symmetric cryptography. Symmetric cryptography is much faster than asymmetric ciphers, but the requirements for key exchange make them hard to use. To remedy this imperfection, a hybrid-key based image encryption and authentication scheme is proposed in this paper. In particular, ergodic matrices are utilized not only as public keys throughout the encryption/decryption process, but also as essential parameters in the confusion and diffusion stages. The experimental results, statistical analysis and sensitivity-based tests confirm that, compared to the existing chaos-based cryptosystems, the proposed image encryption scheme provides a more secure means of image encryption and transmission.
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Статья научная
This paper projects, the impact & accuracy of speech compression on AER systems. The effects of various codecs like MP3, Speex, and Adaptive multi-rate(NB & WB) are compared with the uncompressed speech signal. Loudness enlistment, or a steeper-than-normal increase in perceived loudness with presentation level, is associated with sensorineural hearing loss. Amplitude compression is frequently used to compensate for this abnormality, such as in a hearing aid. As an alternative, one may enlarge these by methods of expansion as speech intelligibility has been represented as the perception of rapid energy changes, may make communication more understandable. However, even if these signal-processing methods improve speech understanding, their design and implementation may be constrained by insufficient sound quality. Therefore, syllabic compression and temporal envelope expansion were assessed for in speech intelligibility and sound quality. An adaptive technique based on brief, commonplace words either in noise or with another speaker competing was used to assess the speech intelligibility. Speech intelligibility was tested in steady-state noise with a single competing speaker using everyday sentences. The sound quality of four artistic excerpts and quiet speech was evaluated using a rating scale. With a state-of-art, spectral error, compression error ratio, and human labeling effects, The experiments are carried out using the Telugu dataset and well-known EMO-DB. The results showed that all speech compression techniques resulted in reduce of emotion recognition accuracy. It is observed that human labeling has better recognition accuracy. For high compression, it is advised to use the overall mean of the unweighted average recall for the AMR-WB and SPEEX codecs with 6.6 bit rates to provide the optimum quality for data storage.
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Estimation and Statistical Analysis of Physical Task Stress on Human Speech Signal
Статья научная
Human speech signal is an acoustic wave, which conveys the information about the words or message being spoken, identity of the speaker, language spoken, the presence and type of speech pathologies, the physical and emotional state of the speaker. Speech under physical task stress shows variations from the speech in neutral state and thus degrades the speech system performance. In this paper we have characterized the voice samples under physical stress and the acoustic parameters are compared with the neutral state voice parameters. The traditional voice measures, glottal flow parameters, mel frequency cepstrum coefficients and energy in various frequency bands are used for this characterization. T-test is performed to check the statistical significance of parameters. Significant variations are noticed in the parameters under two states. Pitch, intensity, energy values are high for the physically stressed voice; On the other hand glottal parameter values get decreased. Cepstrum coefficients shift up from the coefficients of neutral state voice samples. Energy in lower frequency bands was more sensitive to physical stress. This study improves the performance of various speech processing applications by analyzing the unwanted effect of physical stress in voice.
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