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Scalable Vector Graphics (SVG), Version 1.1

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Format Description Properties Explanation of format description terms

Identification and description Explanation of format description terms

Full name Scalable Vector Graphics (SVG) 1.1
Description

Scalable Vector Graphics (SVG) is an open standard developed and maintained under the auspices of the World Wide Web Consortium (W3C). The first edition of SVG 1.1 was published as a W3C Recommendation in January 2003, followed by a second edition in August 2011.

SVG is a language for describing two-dimensional graphics in XML. The XML DTD for SVG (version 1.x) allows for three types of graphic objects: vector graphic shapes (e.g., paths consisting of straight lines and curves), raster graphics (raster images), and text. Graphical objects can be grouped, styled, transformed and composited into previously rendered objects. The feature set includes nested transformations, clipping paths, alpha masks, filter effects and template objects. SVG may also be used for animations.

See SVG_family for more detail on the features supported in SVG and the structure of SVG files.

Production phase Generally a final-state (end-user delivery) format.
Relationship to other formats
    Subtype of SVG_family, Scalable Vector Graphics (SVG) File Format Family
    Subtype of XML, XML (EXtensible Markup Language)
    Defined via XML_DTD, XML Document Type Definition (DTD)
    Has earlier version Scalable Vector Graphics (SVG), Version 1.0 (2001), not described separately at this Web site.
    Has later version SVG_2, Scalable Vector Graphics (SVG), Version 2.. This update is under development. As of April 2020, a W3C Candidate Recommendation, issued October 4, 2018, is available at http://www.w3.org/TR/SVG2/. The most recent editor's draft can be found at https://svgwg.org/svg2-draft/. Work on a Version 1.2 of the full SVG standard has been abandoned.
    Has modified version SVG_Tiny_1_2, Scalable Vector Graphics (SVG) Tiny, Version 1.2. SVG Profile intended for implementation on a range of devices, including cellphones and PDAs as well as laptops and personal computers.
    Has subtype Two reduced profiles of SVG 1.1 for mobile devices: SVG Basic 1.1 and SVG Tiny 1.1, not described separately at this website. See Mobile SVG Profiles: SVG Tiny and SVG Basic. W3C Recommendation 14 January 2003.
    Used by EPUB_2, EPUB, Electronic Publication, Version 2. EPUB_2 readers are required to recognize and display embedded SVG images.
    Used by EPUB_3, Electronic Publication, Version 3. EPUB_3 uses a restricted subset of SVG 1.1 to represent inline vector graphics in documents based on XHTML and in standalone SVG-based EPUBs.
    Used by ODF_family, OpenDocument Format (ODF) Family, OASIS and ISO/IEC 26300. ODF uses the svg: prefix for elements and attributes compatible with SVG 1.1.
    Used by HTML_5, HyperText Markup Language (HTML) 5. SVG 1.1 was supported for embedding within HTML through HTML 5.2. See HTML 5.2: 4.7.18. SVG. As of March 2020, HTML Living Standard: 4.8.17 SVG refers to SVG 2.

Local use Explanation of format description terms

LC experience or existing holdings None
LC preference The Library of Congress Recommended Formats Statement (RFS) includes SVG as a preferred format for other graphic images in digital form. The RFS does not specify a version of SVG.

Sustainability factors Explanation of format description terms

Disclosure Open standard from W3C.
    Documentation Scalable Vector Graphics (SVG) 1.1 (Second Edition). SVG_1_1 was originally published in 2003. The Second Edition includes clarifications and corrections for errata but no new features, released on August 16, 2011. The XML DTD defining the specification is in Appendix A of the specification document and also at https://www.w3.org/Graphics/SVG/1.1/DTD/svg11-flat-20110816.dtd
Adoption

Although SVG 1.0 was adopted as a W3C Recommendation in September 2001, there was not widespread built-in support in browsers for some years. Adobe offered SVG Viewer as a browser plugin. The Apache Batik project offered a toolkit with modules for parsing, viewing, and generating SVG; it could be used on a server to transform SVG to PNG or JPEG for browsers without SVG support. Gradual adoption of HTML 5 (first released in 2008, and approved as a W3C Recommendation in 2014) led to more general native support for SVG by browsers. HTML 5 allows SVG markup within <svg> elements inside HTML markup. By 2014, mainstream browsers supported SVG 1.1 without a plugin. An infographic published in late 2014, indicated that support was full in Safari, Firefox, Chrome, and Opera; support in IE started with IE 9; and support in Android with version 4. For current analysis of browser support, see SVG in HTML img element and Inline SVG in HTML5 from caniuse.com. Testing SVG support across browser engines explores support by the engines used in various browsers on a test SVG file using elements that artists are likely to use.

SVG images can be uploaded to Wikipedia, but are converted to PNG files in various sizes for display. Help:SVG for Wikimedia Commons indicates that the rendering library librsvg is used by MediaWiki to rasterize SVG files into PNG bitmap files for serving to Wikimedia and Wikipedia pages. One reason for the conversion to PNG is that rendering an SVG in real-time slows down older computers or operating systems. This process eliminates any animation or interactivity. Mediawiki description pages (e.g., https://commons.wikimedia.org/wiki/File:SVG_logo.svg) provide access to the source SVG image.

Over the years, SVG has stimulated great enthusiasm in users and groups. See Useful references below, including for archived captures of the LearnSVG and svg.org sites, which are no longer online. An international conference devoted to SVG (initially called SVG Open, and later The Graphical Web) was held every year between 2002 and 2016 (with the exception of 2006). See the conference archive.

See also SVG_family.

    Licensing and patents No special issues. After publication of the first edition of SVG 1.1, the SVG Working Group was not aware of any royalty-bearing patents they believe to be essential to SVG.
Transparency Based on XML, hence inherently transparent.
Self-documentation Includes <metadata> element designed to hold elements from other XML namespaces. Hence an SVG file can contain rich descriptive or administrative metadata using any other DTD.
External dependencies None
Technical protection considerations None

Quality and functionality factors Explanation of format description terms

Still Image
Normal rendering Good support.
Clarity (high image resolution)

The intent of SVG is for images to be inherently scalable. The specification supports optional settings for rendering hints: crispEdges and geometricPrecision.

Color properties in SVG 1.1 are expected to be defined using a CSS2-compatible specification for a color in the sRGB color space, using either a keyword or numerical RGB specification. For the numerical specification, see 4.3.6 Colors in the CSS2 specification. The SVG 1.1 specification includes a more extensive list of recognized color keywords than CSS2.

Color maintenance SVG content can specify an alternate color specification using a profile as defined by the International Color Consortium (ICC). See the ICC Profile Format Specification. ICC.1:2004-10. If ICC-based colors are provided and the SVG user agent supports ICC color, then the ICC-based color takes precedence over the sRGB color specification. See 11.2 Specifying paint in the SVG 1.1 specification.
Support for vector graphics, including graphic effects and typography Rich support.
Support for multispectral bands Not applicable.
Functionality beyond normal rendering Support for animations. Text in alternate languages for labels, etc.

File type signifiers and format identifiers Explanation of format description terms

Tag Value Note
Filename extension svg
 
Internet Media Type image/svg+xml
Registration is in Appendix P of the SVG 1.1 specification. Used as example in IETF RFC 3023: XML Media Types.
Internet Media Type image/svg-xml
Found in practice, probably because usage of SVG files on the web began before IETF published RFC 3023: XML Media Types. See Build Flexible, Lightweight XML-Based Images for ASP.NET Using Scalable Vector Graphics from Microsoft's MSDN Magazine, July 2003, which uses this media type in examples.
Magic numbers See note.  None specified in Appendix P: Media Type Registration for image/svg+xml. A typical SVG 1.1 stand-alone file begins with <?xml version="1.0" standalone="no"?> followed by a DOCTYPE declaration that includes the string PUBLIC "-//W3C//DTD SVG 1.1//EN". Note that case is not significant in this string.
XML DOCTYPE declaration <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
For SVG 1.1, a conforming stand-alone file should have a document type declaration before the mandatory root <svg> tag. The declaration must include the string PUBLIC "-//W3C//DTD SVG 1.1//EN". Note that case is not significant in this string.
Pronom PUID fmt/92
See https://www.nationalarchives.gov.uk/PRONOM/fmt/92.
Wikidata Title ID Q2078
No version declared. See https://www.wikidata.org/wiki/Q2078.

Notes Explanation of format description terms

General

See SVG_family.

History

See SVG_family


Format specifications Explanation of format description terms


Useful references

URLs


Last Updated: 08/10/2021