In digital image processing, filtering tasks are typically implemented using filtering masks of very small sizes, for instance, 3x3, 5x5, or 7x7. The choice of filtering coefficients are usually heuristic, without rigorous mathematical derivation. In this work, we propose a constrained least-squared (LS) error approach to design 5x5 image filtering masks, which have moderate degrees of freedom....

In magnetic resonance imaging (MRI) images, noise is a common issue and it is locally signal dependent. Theoretical expectation of noise measured in unfiltered images is found to be normally distributed, spatially invariant and white. Therefore, the noise has to be removed before processing stage. In this work, there are three different filtering algorithms which are median filter (MF), adaptiv...

Persian juniper and Pistachio are grown in low density in the rangelands of North-East of Iran. These rangelands are populated by evergreen conifers, which are widespread and present at low-density and sparse shrub of pistachio in Iran, that are not only environmentally but also genetically essential as seed sources for pistachio improvement in orchards. Rangelands offer excellent opportunities...

Rank filter is a non-linear filter used in image processing for impulse noise removal, morphological operations, and image enhancement. Real-time applications, such as video and high-speed acquisition cameras, often require the rank filter, and the much simpler median filter. Implementing the rank filter in hardware, can achieve the required speeds for these applications. Bit-serial algorithm c...

A simplified version of the gradient descent method is introduced as a straightforward way to find optimal 3x3 CNN templates for the inversion of known point spread functions (PSF). In practical applications the determination of this inverse is necessary to fulfil deconvolution tasks. The proposed method is much faster than the previously applied algorithms (like genetic algorithm) and still, i...

Abstract Malaysia’s coastline is constantly exposed to ocean threats, resulting in coastal erosion and sea-level rise. Pulau Tuba’s a part of Langkawi which known as popular tourist destination Malaysia. This study focuses on using remote sensing Geographical Information System (GIS) tools examine changes along the Tuba, Langkawi, during six-year period. In this research, were analyzed Sentinel...

Noise in images can be found in almost scanning documents. The picture and text can be contaminated by additive noise from document scanning process or dirtiness in the document itself. This paper presents a scheme for Salt and Pepper noise reduction. This scheme combines the characteristics of an Applied kFill Algorithms and Median Filter by using window size of 3x3 and 5x5, depends on size of...

simulated increased activation of ΔCBF =50% of baseline centered on a 100% GM voxel. The following images (left to right) show results from the PVE-corrected method with kernel sizes of 3x3, 5x5, 9x9, 11x11, 13x13, respectively. Note the dilution effect of the larger kernels. Fig.3: Images of: SPGR (left) and PVE-corrected CBF (right). Note good detection of the ischemic region. The observed le...

In this paper we study the space of natural images locally. We apply the techniques of computational algebraic topology to the space of 3x3 and 5x5 high-contrast patches and show that in both cases, the subspace of linear and quadratic gradient patches, which forms a dense subset inside the space of all high-contrast patches, possesses an interesting topological filtration and is itself topolog...

In this paper problem of edge detection in digital images is considered. Edge detection based on morphological operators was applied on two sets (brain & chest) ct images. Three methods of edge detection by applying line morphological filters with multi structures in different directions have been used. 3x3 filter for first method, 5x5 filter for second method, and 7x7 filter for third method. ...