Venugopal K R

Bio: Venugopal K R is an academic researcher. The author has contributed to research in topics: Image histogram & Steganalysis. The author has an hindex of 2, co-authored 3 publications receiving 33 citations.

Automatic Image Segmentation using Wavelets

Abstract: Model-Based image segmentation plays a dominant role in image analysis and image retrieval. To analyze the features of the image, model based segmentation algorithm will be more efficient compared to non-parametric methods. In this paper, we proposed Automatic Image Segmentation using Wavelets (AISWT) to make segmentation fast and simpler. The approximation band of image Discrete Wavelet Transform is considered for segmentation which contains significant information of the input image. The Histogram based algorithm is used to obtain the number of regions and the initial parameters like mean, variance and mixing factor. The final parameters are obtained by using the Expectation and Maximization algorithm. The segmentation of the approximation coefficients is determined by Maximum Likelihood function. It is observed that the proposed method is computationally efficient allowing the segmentation of large images and performs much superior to the earlier image segmentation methods.

An OLBP Based Transform Domain FaceRecognition

Abstract: The face is an efficient physiological biometric trait to authenticate a person without any cooperation. In this paper, we propose an Overlap Local Binary Pattern (OLBP) on Transform Domain based Face Recognition (OTDFR). The two sets of OLBP features are generated from transform domain. The first set of Overlap Local Binary Pattern (OLBP) features are extracted from Dual Tree Complex Wavelet Transform (DTCWT) coefficients of High frequency components of Discrete Wavelet Transforms (DWT). The second set of OLBP features are extracted from DTCWT coefficients. The final features are generated by concatenating features of set 1 and set 2. The test image features are compared with database features using Euclidian Distance (ED). It is observed that the percentage recognition rate is high in the case of proposed algorithm compared to existing algorithms

Detecting Original Image Using Histogram, DFT

Abstract: Information hiding for covert communication is rapidly gaining momentum. With sophisticated techniques being developed in steganography, steganalysis needs to be universal. In this paper we propose Universal Steganalysis using Histogram, Discrete Fourier Transform and SVM (SHDFT). The stego image has irregular statistical characteristics as compare to cover image. Using Histogram and DFT, the statistical features are generated to train OneClass SVM to discriminate the cover and stego image. SHDFT algorithm is found to be efficient and fast since the number of statistical features is less compared to the existing algorithm.

Ripeness Classification of Bananas Using an Artificial Neural Network

Abstract: The quality of fresh banana fruit is a main concern for consumers and fruit industrial companies. The effectiveness and fast classification of banana’s maturity stage are the most decisive factors in determining its quality. It is necessary to design and implement image processing tools for correct ripening stage classification of the different fresh incoming banana bunches. Ripeness in banana fruit generally affects the eating quality and the market price of the fruit. In this paper, an automatic computer vision system is proposed to identify the ripening stages of bananas. First, a four-class homemade database is prepared. Second, an artificial neural network-based framework which uses color, development of brown spots, and Tamura statistical texture features is employed to classify and grade banana fruit ripening stage. Results and the performance of the proposed system are compared with various techniques such as the SVM, the naive Bayes, the KNN, the decision tree, and discriminant analysis classifiers. Results reveal that the proposed system has the highest overall recognition rate, which is 97.75%, among other techniques.

Color image segmentation based on different color space models using automatic GrabCut.

Abstract: This paper presents a comparative study using different color spaces to evaluate the performance of color image segmentation using the automatic GrabCut technique. GrabCut is considered as one of the semiautomatic image segmentation techniques, since it requires user interaction for the initialization of the segmentation process. The automation of the GrabCut technique is proposed as a modification of the original semiautomatic one in order to eliminate the user interaction. The automatic GrabCut utilizes the unsupervised Orchard and Bouman clustering technique for the initialization phase. Comparisons with the original GrabCut show the efficiency of the proposed automatic technique in terms of segmentation, quality, and accuracy. As no explicit color space is recommended for every segmentation problem, automatic GrabCut is applied with RGB, HSV, CMY, XYZ, and YUV color spaces. The comparative study and experimental results using different color images show that RGB color space is the best color space representation for the set of the images used.

Adaptive noise-reducing anisotropic diffusion filter

Abstract: In image processing and computer vision, the denoising process is an important step before several processing tasks. This paper presents a new adaptive noise-reducing anisotropic diffusion (ANRAD) method to improve the image quality, which can be considered as a modified version of a speckle-reducing anisotropic diffusion (SRAD) filter. The SRAD works very well for monochrome images with speckle noise. However, in the case of images corrupted with other types of noise, it cannot provide optimal image quality due to the inaccurate noise model. The ANRAD method introduces an automatic RGB noise model estimator in a partial differential equation system similar to the SRAD diffusion, which estimates at each iteration an upper bound of the real noise level function by fitting a lower envelope to the standard deviations of pre-segment image variances. Compared to the conventional SRAD filter, the proposed filter has the advantage of being adapted to the color noise produced by today's CCD digital camera. The simulation results show that the ANRAD filter can reduce the noise while preserving image edges and fine details very well. Also, it is favorably compared to the fast non-local means filter, showing an improvement in the quality of the restored image. A quantitative comparison measure is given by the parameters like the mean structural similarity index and the peak signal-to-noise ratio.

A robust fuzzy clustering technique with spatial neighborhood information for effective medical image segmentation: An efficient variants of fuzzy clustering technique with spatial information for effective noisy medical image segmentation

Abstract: Segmentation is an important step in many medical imaging applications and a variety of image segmentation techniques do exist. Of them, a group of segmentation algorithms is based on the clustering concepts. In our research, we have intended to devise efficient variants of Fuzzy C-Means (FCM) clustering towards effective segmentation of medical images. The enhanced variants of FCM clustering are to be devised in a way to effectively segment noisy medical images. The medical images generally are bound to contain noise while acquisition. So, the algorithms devised for medical image segmentation must be robust to noise for achieving desirable segmentation results. The existing variants of FCM-based algorithms, segment images without considering the spatial information, which makes it sensitive to noise. We proposed the algorithm, which incorporate spatial information into FCM, have shown considerable resilience to noise, yet with increased noise levels in images, these approaches have not performed exceptionally well. In the proposed research, the input noisy medical images are employed to a denoising algorithm with the help of effective denoising algorithm prior to segmentation. Moreover, the proposed approach will improve upon the existing variants of FCM-based segmentation algorithms by integrating the spatial neighborhood information present in the images for better segmentation. The spatial neighborhood information of the images will be determined using a factor that represents the spatial influence of the neighboring pixels on the current pixel. The employed factor works on the assumption that the membership degree of a pixel to a cluster is greatly influenced by the membership of its neighborhood pixels. Subsequently, the denoised images will be segmented using the designed variants of FCM. The proposed segmentation approach will be robust to noisy images even at increased levels of noise, thereby enabling effective segmentation of noisy medical images.

Remote Sensing Satellite Image Processing Techniques for Image Classification: A Comprehensive Survey

Abstract: This paper is a brief survey of advance technological aspects of Digital Image Processing which are applied to remote sensing images obtained from various satellite sensors. In remote sensing, the image processing techniques can be categories in to four main processing stages: Image preprocessing, Enhancement, Transformation and Classification. Image pre-processing is the initial processing which deals with correcting radiometric distortions, atmospheric distortion and geometric distortions present in the raw image data. Enhancement techniques are applied to preprocessed data in order to effectively display the image for visual interpretation. It includes techniques to effectively distinguish surface features for visual interpretation. Transformation aims to identify particular feature of earth’s surface and classification is a process of grouping the pixels, that produces effective thematic map of particular land use and land cover.