2. Conference Papers
Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/1/7
Browse
23 results
Search Results
Item Pipelined implementation of high radix adaptive CORDIC as a coprocessor(2016) Oza, S.S.; Shah, A.P.; Thokala, T.; Sumam, David S.The Coordinate Rotational Digital Computer (CORDIC) algorithm allows computation of trigonometric, hyperbolic, natural log and square root functions. This iterative algorithm uses only shift and add operations to converge. Multiple fixed radix variants of the algorithm have been implemented on hardware. These have demonstrated faster convergence at the expense of reduced accuracy. High radix adaptive variants of CORDIC also exist in literature. These allow for faster convergence at the expense of hardware multipliers in the datapath without compromising on the accuracy of the results. This paper proposes a 12 stage deep pipeline architecture to implement a high radix adaptive CORDIC algorithm. It employs floating point multipliers in place of the conventional shift and add architecture of fixed radix CORDIC. This design has been synthesised on a FPGA board to act as a coprocessor. The paper also studies the power, latency and accuracy of this implementation. � 2015 IEEE.Item Estimation of attack time constant for dynamic range compressors in hearing AIDS(2016) Deepu, S.P.; Sumam, David S.; Ramesh, Kini, M.Dynamic Range Compression (DRC) is a key component in all modern Hearing AIDS. Attack and Release time constants decide the speed with which the DRC should act to the incoming signal amplitude variation. So an accurate estimation of time constants gives a precise control over the DRC behavior. In this paper we examined various errors that occur in the output of the DRC while using conventional methods which affect attack and release time constants adversely. New methods are proposed for a better estimation of time constants in DRC. Since all the modifications are made in the estimation of attack time, there is no need to change the existing hardware for DRC. The proposed algorithm gives perfect output characteristics with zero error for test signals defined in ANSI S3.22 standards for hearing aid specifications. � 2016 IEEE.Item Low cost black box for cars(2013) Patil, C.; Marathe, Y.; Amoghimath, K.; Sumam, David S.Automotive electronics plays a significant role in the automobile industry and provides luxurious features and more importantly addresses the safety and security concerns. The work presented in this paper aims at providing a cost effective solution to the design and development of an event data recorder which has been basically adopted from the aviation sector considering the need and the correlated benefits. The paper presents an integrated design of the black box with the basic features of the data recorder which could be very useful for domestic vehicles and at the same time it also hosts several additional features that could assist in mitigating the number of accidents, or at bare minimum, will serve as an analysis tool to prevent future accidents by analyzing the previous accidents. The black box also provides automatic accident notification system which helps in informing the nearest hospital and the traffic authority by providing not only the coordinates of the accident but also the exact physical address for immediate medical attention which can save numerous lives every day. The black box also hosts several other features like CAN compatibility, attractive user console and advanced web tracking anytime and from anywhere. Thus the overall cost is highly optimized by integrating such multiple features. � 2013 IEEE.Item Irreversible wavelet compression of radiological images based on visual threshold(2016) Chandrika, B.K.; Aparna, P.; Sumam, David S.Visually lossless irreversible coding permit compression algorithms to improve the compression gain without disturbing the visual image quality. This paper proposes a novel coding scheme in which wavelet based visual model is embedded into lossless compression algorithm to compress the volumetric medical image data. Obtained experimental results are compared with numerically lossless compression schemes such as Differential Pulse Code Modulation (DPCM), Joint Photographic Experts Group-Lossless (JPEG-LS), JPEG-2000 and High Efficiency Video Coding (HEVC). The proposed method achieves reduced bit rate without deteriorating the visual quality of the resulting images. � 2015 IEEE.Item Hardware Acceleration of Optically Labeled Human Genome Sequencing using a Novel Algorithm(2018) Mulani, K.S.; Kumar, H.; Gaurav, M.K.; Sumam, David S.Recently, reconstruction of the entire DNA sequence from optically labeled genomes has been explored. In this paper, we present details of a novel algorithm for this genome assembly. We elucidate the design methodology and results for a multi-core CPU (1.98x speedup) and FPGA (7.022x speedup) implementation to accelerate the computations. � 2018 IEEE.Item Fully automated radiogrammetric measurement of third metacarpal bone from hand radiograph(2016) Areeckal, A.S.; Sumam, David S.; Kocher, M.; Jayasheelan, N.; Kamath, J.Osteoporosis is a disease caused by reduction of bone mass, bone strength and deterioration of bone structure. The gold standard method for diagnosis of osteoporosis is measurement of bone mineral density (BMD) using Dual X-ray Absorptiometry (DXA). However, DXA is expensive and not widely available in developing countries. An alternative cost-effective method for measurement of bone loss and strength is metacarpal radiogrammetry, by which geometric measurements of cortical bone of the metacarpal bone are measured. In this paper, we propose a fully automated method for segmentation of third metacarpal bone from hand radiograph and radiogrammetric measurements using mathematical morphology. Cortical width and thickness are measured from the endosteal and periosteal edges of the metacarpal bone using which bone indices which help in diagnosis of osteoporosis can be computed. The proposed segmentation method was tested on 157 hand X-ray images. A success rate of 94.9% is obtained for automatic detection of third metacarpal bone. Evaluation of cortical measurements of 3 calibrated images is done by comparing the results with ground truth. The mean accuracy error obtained was 0.02cm and 0.04cm for cortical width and medullary width, respectively. � 2016 IEEE.Item FPGA implementation of adaptive beamforming in hearing aids(2017) Samtani, K.; Thomas, J.; Varma, G.A.; Sumam, David S.; Deepu, S.P.Beamforming is a spatial filtering technique used in hearing aids to improve target sound reception by reducing interference from other directions. In this paper we propose improvements in an existing architecture present for two omnidirectional microphone array based adaptive beamforming for hearing aid applications and implement the same on Xilinx Artix 7 FPGA using VHDL coding and Xilinx Vivador 2015.2. The nulls are introduced in particular directions by combination of two fixed polar patterns. This combination can be adaptively controlled to steer the null in the direction of noise. The beamform patterns and improvements in SNR values obtained from experiments in a conference room environment are analyzed. � 2017 IEEE.Item Early diagnosis of osteoporosis using active appearance model and metacarpal radiogrammetry(2018) Sam, M.; Areeckal, A.S.; Sumam, David S.Osteoporosis is a condition of fragile bone with an increased susceptibility to fracture. Since the gold standard method used for the diagnosis of osteoporosis, Dual X-ray Absorptiometry (DXA), is expensive and not widely available in low economies, there is a need for low cost approaches to detect bone loss in people. A new automated radiogrammetric method for early diagnosis of osteoporosis from a single hand radiograph is proposed. In this technique, the third metacarpal bone is segmented from hand X-ray images using Active Appearance Models (AAM). Points of interest acquired from the segmented bone are used to take radiogrammetric measurements, from which bone indices are calculated. Data used in this work was acquired from 138 subjects in two hospitals in India. Significant radiogrammetric features were selected using statistical analysis. The bone indices are observed to be significantly correlated with Bone Mineral Density (BMD) of the lumbar spine measured using DXA. Different classification models were trained using the significant features. The results obtained are promising and can be used as a cost effective diagnostic tool for early detection of osteoporosis. � 2017 IEEE.Item Design and implementation of an automatic traffic sign recognition system on TI OMAP-L138(2013) Phalguni; Ganapathi, K.; Madumbu, V.; Rajendran, R.; Sumam, David S.This paper discusses the design and processor implementation of a system that detects and recognizes traffic signs present in an image. Morphological operators, segmentation and contour detection are used for isolating the Regions of Interest (ROIs) from the input image, while five methods - Hu moment matching, histogram based matching, Histogram of Gradients based matching, Euclidean distance based matching and template matching are used for recognizing the traffic sign in the ROI. A classification system based on the shape of the sign is adopted. The performance of the various recognition methods is evaluated by comparing the number of clock cycles used to run the algorithm on the Texas Instruments TMS320C6748 processor. The use of multiple methods for recognizing the traffic signs allows for customization based on the performance of the methods for different datasets. The experiments show that the developed system is robust and well-suited for real-time applications and achieved recognition and classification accuracies of upto 90%. � 2013 IEEE.Item Copy-Move Forgery Detection using SIFT and GLCM-based Texture Analysis(2019) Chowdhury, M.; Shah, H.; Kotian, T.; Subbalakshmi, N.; Sumam, David S.Easier access to editing tools and growing risk of image manipulation has encouraged extensive research in copy-move forgery detection. Although the current methods have been able to detect this tampering to a good extent, their accuracies drop when tested on images with different sizes of tampered regions and in the presence of similar but genuine objects in the image. In this paper, these issues are addressed by including a novel GLCM-based Texture Analysis Filter that gives information about the textural similarity of the keypoint neighbourhoods by using difference of GLCM contrasts as the similarity metric. Experimental results show that the proposed technique can address a variety of different tampering scenarios and outperforms the existing state-of-the-art Copy-Move Forgery Detection(CMFD) techniques by handling multiple forgeries, returning corresponding geometrical parameters and significantly improving the false positive rates. � 2019 IEEE.
- «
- 1 (current)
- 2
- 3
- »