Consider edge colorings of directed graphs where edges of the form v1v2 and v2v3 must have different colors. Here, v1 ≠ v2 , v2 ≠ v3 but v1 = v3 is possible. It is known that this coloring induces a vertex coloring by sets of edge colors, in which edge v1v2 in the graph implies that the set color of v1 contains an element not in the set color of v2; conversely, each such set coloring of vertice...

CMYK color separation is a technique commonly used in printing to reproduce mutli-color images. However, the color planes are generally not perfectly aligned with respect to each other when they are rendered by the imaging stations. This phenomenon, called color plane mis-registration, causes gap and halo artifacts. Trapping algorithms aim to reduce these artifacts by scanning through an image,...

Edge detection of image is used to improve the visual recognition ability of the pattern by identifying points with obvious variation of brightness in a digital image. In the case of uneven conversion of color information of antiharmonic image pixel, edge detection becomes difficult. Traditional edge detection algorithm of anti-harmonic image adopts tensor model, as due to relatively simple str...

We present PRISMA’s Video Copy Detection system (P-VCD). The system is based on visual-only global descriptors, weighted combinations of distances, a pivotbased index structure, and a novel approximated search and voting algorithm for copy localization. We submitted four Runs to TRECVID 2010 CCD task: PRISMA.m.balanced.ehdNgryhst: a combination of edge histogram and gray histogram. PRISMA.m.bal...

A vertex (edge) coloring φ : V → {1, 2, . . . , t} (φ′ : E → {1, 2, . . . , t}) of a graph G = (V,E) is a vertex (edge) t-ranking if, for any two vertices (edges) of the same color, every path between them contains a vertex (edge) of larger color. The vertex ranking number χr(G) (edge ranking number χ′ r (G)) is the smallest value of t such that G has a vertex (edge) t-ranking. In this paper we...

Non-Photo-Realistic Rendering (NPR) is becoming increasingly important research topic in computer graphics and image processing. This paper puts forward a novel method for automatically generating a pencil sketch from a real 2D color image in non-photo-realistic rendering. First of all, the edge of the color image is detected by Sobel operator. Secondly, the color image is sharpened by Unsharp ...

An r-edge coloring of a graph G is a mapping h : E(G) → [r], where h(e) is the color assigned to edge e ∈ E(G). An exact r-edge coloring is an r-edge coloring h such that there exists an e ∈ E(G) with h(e) = i for all i ∈ [r]. Let h be an edge coloring of G. We say G is rainbow if no two edges in G are assigned the same color by h. The anti-Ramsey number, AR(G,n), is the smallest integer r such...

This thesis addresses problems in computer vision and pattern recognition using graphs. The particular focus is on graph matching and characterization using edge-based operators. The thesis commences with a brief introduction in Chapter 1, followed by a review of the relevant literature in Chapter 2. The remainder of the thesis is organized as follows. Chapter 3 discusses the structure of the I...

Given a c-edge-colored graph G on n vertices, we define the degree matrix M as the c× n matrix whose entry dij is the degree of color i at vertex vj . We show that the obvious necessary conditions for a c× n matrix to be the degree matrix of a c-edge-colored forest on n vertices are also sufficient. It is well known that non-negative integers d1, d2, . . . , dn form a degree list of a forest on...