scholarly journals Reduction of Impulsive Noise from Speech and Audio Signals by using Sd-Rom Algorithm

2021 ◽  
Vol 10 (1) ◽  
pp. 265-268
Author(s):  
G.Manmadha Rao* ◽  
Raidu Babu D.N ◽  
Krishna Kanth P.S.L ◽  
Vinay B. ◽  
Nikhil V.
Keyword(s):  
Impulse Noise ◽  
Impulsive Noise ◽  
Rank Order ◽  
Signal To Noise Ratio ◽  
Audio Signal ◽  
Window Size ◽  
Mean Value ◽  
Audio Signals ◽  
Signal To Noise ◽  
Noise Ratio

Removal of noise is the heart for speech and audio signal processing. Impulse noise is one of the most important noise which corrupts different parts in speech and audio signals. To remove this type of noise from speech and audio signals the technique proposed in this work is signal dependent rank order mean (SD-ROM) method in recursive version. This technique is used to replace the impulse noise samples based on the neighbouring samples. It detects the impulse noise samples based on the rank ordered differences with threshold values. This technique doesn’t change the features and tonal quality of signal. Rank ordered differences is used for detecting the impulse noise samples in speech and audio signals. Once the sample is detected as corrupted sample, that sample is replaced with rank ordered mean value and this rank ordered mean value depends on the sliding window size and neighbouring samples. This technique shows good results in terms of signal to noise ratio (SNR) and peak signal to noise ratio (PSNR) when compared with other techniques. It mainly used for removal of impulse noises from speech and audio signals.

Reversible Watermarking on Stereo Audio Signals by Exploring Inter-Channel Correlation

2019 ◽  
Vol 11 (1) ◽  
pp. 29-45
Author(s):  
Yuanxin Wu ◽  
Wen Diao ◽  
Dongdong Hou ◽  
Weiming Zhang
Keyword(s):  
Signal To Noise Ratio ◽  
Audio Signal ◽  
Reversible Watermarking ◽  
Experimental Results ◽  
Audio Signals ◽  
Signal To Noise ◽  
Channel Correlation ◽  
Noise Ratio ◽  
Embedding Distortion

A new reversible watermarking algorithm on stereo audio signals is proposed in this article. By utilizing correlations between two channels of audio signal, the authors segment one channel based on another one according to the smoothness. For each segmented sub-host sequence, they estimate its capacity and the corresponding embedding distortion firstly, and then select the optimal combinations of sub-host sequences for embedding. Experimental results indicate that the proposed algorithm can improve SNR (signal to noise ratio) for various kinds of capacity.

scholarly journals PERFORMANCE EVALUATION OF SINGLE CARRIER FREQUENCY DOMAIN EQUILIZER (SC-FDE) OVER IMPULSIVE NOISE CHANNEL

2019 ◽  
Vol 11 (2) ◽  
pp. 270-277
Author(s):  
Hussein Abdullah Leftah ◽  
Husham Lateef Swadi
Keyword(s):  
Frequency Domain ◽  
Carrier Frequency ◽  
Communication Systems ◽  
Impulsive Noise ◽  
Signal To Noise Ratio ◽  
High Signal ◽  
Signal To Noise ◽  
Single Carrier ◽  
Noise Ratio ◽  
Error Floors

Impulsive noise is considered as one of the major source of disturbance in the state-of-the-art multicarrier (MC) communication systems. Therefore, several techniques are being constantly proposed to eliminate the effect of such noise. In this work, a time domain matrix interleaved is compiled with a single carrier frequency domain equalizer (SC-FDE) is proposed to reduce the deleterious effects of impulsive noise. A mathematical model for the proposed scheme is also presented in this paper. Simulation results show that the proposed technique superiors the interleaved multicarrier system where the proposed scheme can completely avoid the error floors not only at high signal-to-noise ratio (SNR) but also at heavily distributed impulsive noise. The bit-error-rate (BER) of the alternative proposed scheme decreases as the signal-to-noise ratio (SNR) increases whereas the BER of the standard system suffers from error-floors with a constant BER at about 10-3 for about 8 dB SNR for medium and heavily impulsive noise.

Elastographic Imaging Using Staggered Strain Estimates

2002 ◽  
Vol 24 (4) ◽  
pp. 229-245 ◽  
Author(s):  
S. Srinivasan ◽  
J. Ophir ◽  
S.K. Alam
Keyword(s):  
Signal To Noise Ratio ◽  
Window Size ◽  
Poor Quality ◽  
Small Distance ◽  
Estimation Technique ◽  
Signal To Noise ◽  
Estimation Techniques ◽  
Strain Estimation ◽  
Noise Ratio ◽  
Data Windows

Conventional techniques in elastography estimate strain as the gradient of the displacement estimates obtained through crosscorrelation of pre- and postcompression rf A-lines. In these techniques, the displacements are estimated over overlapping windows and the strains are estimated as the gradient of the displacement estimates over adjacent windows. The large amount of noise at high window overlaps may result in poor quality elastograms, thus restricting the applicability of conventional strain estimation techniques to low window overlaps, which, in turn, results in a small number of pixels in the image. To overcome this restriction, we propose a multistep strain estimation technique. It computes the first elastogram using nonoverlapped windows. In the next step, the data windows are shifted by a small distance (small fraction of window size) and another elastogram is produced. This is repeated until the cumulative shift equals/exceeds the window size and all the elastograms are staggered to produce the final elastogram. Simulations and experiments were performed using this technique to demonstrate significant improvement in the elastographic signal-to-noise ratio ( SNRe) and the contrast-to-noise ratio ( CNRe) at high window overlaps over conventional strain estimation techniques, without noticeable loss of spatial resolution. This technique might be suitable for reducing the algorithmic noise in the elastograms at high window overlaps.

scholarly journals A study of the performance of the MSR vegetation index, using probabilistic and geostatistical methods

2007 ◽  
Vol 40 (4) ◽  
pp. 2048
Author(s):  
Aim. G. Skianis ◽  
D. Vaiopoulos ◽  
K. Nikolakopoulos
Keyword(s):  
Vegetation Index ◽  
Signal To Noise Ratio ◽  
Mean Value ◽  
High Signal ◽  
Signal To Noise ◽  
Infrared Band ◽  
Geostatistical Methods ◽  
Noise Ratio ◽  
Good Contrast ◽  
Modified Soil

In the present paper is studied the effect of the MSR (Modified Soil Ratio) vegetation index on multispectral digital images, with the aid of probability theory and geostatistics. Using proper distributions to describe the histograms of the image at the red and infrared band zones, an analytical expression of the distribution g of the MSR values is deduced. The study of the behaviour of g shows that the ratio of the standard deviation to the mean value of the MSR image is higher than that of the NDVI vegetation index, which is quite often used. This means that the MSR vegetation index produces images with a good contrast. It was also observed that the MSR image has a better signal to noise ratio than that of the NDVI image. Finally, the autocorrelograms of the MSR and NDVI images showed that the tonality differences between adjacent pixels of the MSR image are slightly stronger than those of the NDVI image. The general conclusion is that the MSR vegetation index produces images with a good contrast and a high signal to noise ratio, which could aid in making a reliable mapping of the vegetation cover of the area under study

Improvement of Lesion Detectability by Speckle Reduction Filtering: A Quantitative Study

1993 ◽  
Vol 15 (3) ◽  
pp. 181-204 ◽  
Author(s):  
J.T.M. Verhoeven ◽  
J.M. Thijssen
Keyword(s):  
Adaptive Filters ◽  
Signal To Noise Ratio ◽  
Objective Measure ◽  
Window Size ◽  
Nonlinear Filters ◽  
Speckle Reduction ◽  
Signal To Noise ◽  
Lesion Detectability ◽  
Maximum Improvement ◽  
Noise Ratio

An objective measure (Lesion Signal-to-Noise Ratio) quantifying the detectability of lesions in echographic images was employed. This measure was used to determine the performance of digital speckle reduction filters, which were applied to computer simulated ultrasound B-mode images. One linear (mean filter) and two nonlinear filters (median and L2-mean filters) have been investigated. A comparison was made between fixed and adaptive versions of these filters. The influence of the size of the filter window on the Lesion Signal-to-Noise Ratio was systematically investigated. Also, the effect of the shape of the filter window is illustrated. The difference in performance of the linear and nonlinear filters was found to be small. Adaptive filters did not perform significantly better than fixed filters. The maximum improvement of lesion detectability was in the order of 40 percent. The choice of a correct window size was critical. For all types of filters, an optimum window size appeared to be present in the curves relating the Lesion Signal-to-Noise Ratio to this size.

Noise Reduction, Enhancement and Classification for Sonar Images

2021 ◽  
pp. 4439-4452
Author(s):  
Noor H. Resham ◽  
Heba Kh. Abbas ◽  
Haidar J. Mohamad ◽  
Anwar H. Al-Saleh
Keyword(s):  
Signal To Noise Ratio ◽  
Wiener Filter ◽  
Window Size ◽  
Speckle Noise ◽  
Signal To Noise ◽  
Coherent Noise ◽  
Distance Method ◽  
Sliding Windows ◽  
Noise Ratio ◽  
Four Blocks

    Ultrasound imaging has some problems with image properties output. These affects the specialist decision. Ultrasound noise type is the speckle noise which has a grainy pattern depending on the signal. There are two parts of this study. The first part is the enhancing of images with adaptive Weiner, Lee, Gamma and Frost filters with 3x3, 5x5, and 7x7 sliding windows. The evaluated process was achieved using signal to noise ratio (SNR), peak signal to noise ratio (PSNR), mean square error (MSE), and maximum difference (MD) criteria. The second part consists of simulating noise in a standard image (Lina image) by adding different percentage of speckle noise from 0.01 to 0.06. The supervised classification based minimum distance method is used to evaluate the results depending on selecting four blocks located at different places on the image. Speckle noise was added with different percentage from 0.01 to 0.06 to calculate the coherent noise within the image. The coherent noise was concluded from the slope of the standard deviation with the mean for each noise. The results showed that the additive noise increased with the slide window size, while multiplicative noise did not change with the sliding window nor with increasing noise ratio. Wiener filter has the best results in enhancing the noise.

scholarly journals Perbandingan Algoritma Mean Filter, Median Filter dan Wiener Filter pada Aplikasi Restorasi Citra RGB Terdegradasi Impulse Noise Menggunakan The Peak Signal To Noise Ratio (PSNR)

2017 ◽  
Author(s):  
Arnes Sembiring
Keyword(s):  
Impulse Noise ◽  
Signal To Noise Ratio ◽  
Median Filter ◽  
Wiener Filter ◽  
Signal To Noise ◽  
Mean Filter ◽  
Noise Ratio

Artikel ini merupakan versi postprint, artikel ini sudah dipublikasikan pada Jurnal Saintek Fak. Teknik Universitas Islam Sumatera Utara (UISU), ISSN: 2355-2395, Volume 2 Nomor 2 tahun 2015, halaman 234-244

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