Wednesday 13 July 2011

Scalable Images in Linux

Scalable Vector Graphics (SVG) is a family of specifications of an XML-based file format for describing two-dimensional vector graphics, both static and dynamic (i.e. interactive or animated).

The SVG specification is an open standard that has been under development by the World Wide Web Consortium (W3C) since 1999.

SVG images and their behaviors are defined in XML text files. This means that they can be searched, indexed, scripted and, if required, compressed. Since they are XML files, SVG images can be created and edited with any text editor, but drawing programs are also available that support SVG file formats.

All major modern web browsers have at least some degree of support and render SVG markup directly with the exception of any version of Microsoft Internet Explorer (IE) released for the widely used Windows XP.

SVG allows three types of graphic objects: vector graphics, raster graphics, and text. Graphical objects, including PNG and JPEG raster images, can be grouped, styled, transformed, and composited into previously rendered objects. SVG does not directly support z-indices[6] that separate drawing order from document order for overlapping objects, unlike some other vector markup languages like VML. Text can be in any XML namespace suitable to the application, which enhances search ability and accessibility of the SVG graphics. The feature set includes nested transformations, clipping paths, alpha masks, filter effects, template objects and extensibility.

Printing

Though the SVG Specification primarily focuses on vector graphics markup language, its design includes the basic capabilities of a page description language (PDL), like Adobe's PDF. It contains provisions for rich graphics, and is also compatible with CSS for styling purposes. It is unlike XHTML, whose primary purpose is communication of content, not presentation, and therefore specifies objects to be displayed but not where to place such objects. Conversely SVG is an ideal PDL for print-oriented uses, as it contains all the functionality required to place each glyph and image in a chosen location on the final page.

Compression

SVG images, being XML, contain many repeated fragments of text and are thus particularly suited to compression by gzip, though other compression methods may be used effectively. Once an SVG image has been compressed it may be referred to as an "SVGZ" image, with the corresponding filename extension. The resulting file may be as small as 20% of the original size.

Use in Linux

Most images in icon set in themes in gnome and graphics user interfaces uses these scalable images for dynamic imaging displays and thus the use and manupulation of such images could be very vital in development of themes and icon set.The most popular editor for svg images is Inkscape which is able to perform all kinds of editing in a scalable image.

No comments:

Post a Comment