Noise

The most important aspects of image processing are image enhancement. The visual form of an image can be enhanced by using image enhancement techniques for better human interpretation. In this research paper we discuss an   outline and analysis of commonly used image enhancement techniques using finger vein image or personal authentication. Also, experiments are carried out to compare performance of various types of filters for removal of noise from the noisy images through evaluation performance parameter such as mean square error (MSE), peak signal to noise ratio (PSNR) values and structural similarity (SSIM). It was found that application of max filter technique ensures an improved quality of the finger vein image. The mean filter is most advanced in de-noising the images. Mean filter is most efficient in eliminating the salt and pepper noise. From the experiments performed on finger vein image using SDUMLA-HMT database, it is proven that Weiner filters are outstanding for elimination of Gaussian Speckle and Poisson noises and thus, Weiner filter is found to be most appropriate and well-suited for eliminating nearly all types of noise.

 The extant s tudy aimed to analyze the acous tic comfort situation in contemporary apartments based on urban spaces in Tabriz, Iran. This s tudy was conducted using a quantitative method within the field survey at two levels of the ques tionnaire (perceptual situation) and field measurements (acous tical condition). The researcher-made ques tionnaire was used to collect data in the firs t s tep. Architecture experts approved the validity of the ques tionnaire; its reliability was examined using Cronbach's alpha (0.926). All experiments associated with airborne noise field measurements (background sound and sound pressure level) were done using 2260Inves tigator. Firs t, background noise was measured in two open and closed windows inside the considered residential units. In the next s tep, sound pressure level (SPL) Figures were plotted using level rate and sound s tandard in different plan spaces. Ultimately, the authors assessed noise criteria and their difference with sound levels. The results indicated the undeniable effect of traffic, among other variables of acous tic comfort, on dissatisfaction caused by noise in urban areas of Tabriz. This effect was not only definite but also so significant that there was no change in patterns emerging in noise level, even based on the SPL measurements.