Solid freeform fabrication (SFF) processes based on mask image projection such as digital micro-mirror devices (DMD) have the potential to be fast and inexpensive. More and more research and commercial systems have been developed based on such digital devices. However, a digital light processing (DLP) projector based on DMD has limited resolution and certain image blurring. In order to use a DL...

A critical step in defect detection for semiconductor process is to align a test image against a reference. This includes both spatial alignment and grayscale alignment. For the latter, a direct least square approach is not very applicable because the presence of defects would skew the parameters. Instead, we use a linear programming formulation which has the advantage of having a fast algorith...

A digital grayscale image can be described by intensity or pixel values. The gray levels are spread over the images as irregular or inhomogeneous fashion. A number of proposed methods for calculating the optimal thresholding value for image segmentation, but the fractal analysis is an expeditious and significant mathematical approach that distributes with irregular geometric objects. In the rec...

Computer images have three or four color channels, which are grayscale images representing the intensity of colored ink or light at particular places on the screen. These are RGB (Red-Green-Blue) for work that is intended to be shown by light emitting media such as monitors or projectors, and CMYK (Cyan-Magenta-Yellow-Black) for light absorbing media such as printed paper. An alpha channel is o...

Texture regularity is one of the important visual characteristics. It can be used to determine differences in the surface between two objects. Several methods of measurement have been produced by previous researchers.However, in this paper the authors offer a new formula for calculating the regularity of texture features. Regularity is measured by the intensity of the pixels of grayscale images...

This paper presents a fast and accurate algorithm for extracting lines and circular arcs from digital images. Conventional line and circle extraction algorithms first extract the edge pixels and then connect these edge pixels into lines or circles. In contrast the proposed algorithm extracts the lines and circular arcs directly from the input image by tracing the perimeter of an intensity regio...

Video-based face recognition has attracted significant attention in many applications such as media technology, network security, human-machine interfaces, and automatic access control system in the past decade. The usual way for face recognition is based upon the grayscale image produced by combining the three color component images. In this work, we consider grayscale image as well as color s...

Conventional color to grayscale conversion algorithms cannot perform well in certain circumstances and the resultant grayscale images produced have low contrast and interpretability. Thus, we propose a new adaptive approach to overcome the drawback, namely the neighborhood pixels effect approach. In this approach two algorithms are proposed under this approach, namely the Neighborhood Effect Co...

A novel approach for segmentation of grayscale images, which are color scene originally, is proposed. Many algorithms have been elaborated for a grayscale image segmentation. All those approaches have been discussed in a luminance space, because it has been considered that grayscale images do not have any color information. However, a luminance value has color information as a set of correspond...