Brussels / 1 & 2 February 2014


An overview of Sozi

SVG-based zooming presentation software

Initially inspired by the proprietary software Prezi, Sozi is a free and open-source "zooming presentation" tool based on open standards. This talk will expose the general concepts of Sozi and how it benefits from the use of open standards, from a user's as well as a developer's point of view. We will give an overview of the current status of the project and the expected future developments.

Over the last few years, several presentation tools have emerged that provide alternatives to the traditional desktop slideshow software. Some of them, like reveal.js, allow to create slideshows using web standards such as HTML5, CSS3 and JavaScript. Others, like the proprietary software Prezi, have set a new paradigm based on a sequence of camera movements (translations, zooms, rotations) over a single, unlimited canvas where all the visual content of your document is laid out.

Initially inspired by Prezi, Sozi is a free and open-source "zooming presentation" tool based on open standards. A Sozi presentation is an SVG document augmented with presentation data and a player script in JavaScript. As a consequence, such a document can be played directly by any standards-compliant web browser without the need to install a plugin or a specific viewing software. For presentation creators, we have chosen to build the Sozi editor as an extension to the free SVG editor Inkscape. Sozi is open to contributions: volunteers have provided translations to 8 languages, others have created packages for several widely-used GNU/Linux distributions.

While the tool is used on a daily basis by teachers and researchers, several issues prevent a wider adoption:

  • On the editor side, the usability of the user interface needs to be improved but is constrained by the Inkscape extension system.
  • No one has volunteered to create installers for Windows and OS X, so users of these operating systems must install all dependencies manually.
  • On the player side, poor SVG rendering performance in some browsers can make the animations jerky for complex documents that contain gradients and bitmap images.

To address the first two issues, we consider the possibility to create a new editor using web technologies. The current form-based UI would be replaced by direct manipulation and live preview, allowing significant improvement of the user experience. Moreover, the use of JavaScript would allow to share code between the editor and the player.

However, while Sozi has been mostly the work of a single developer working on his spare time, creating a new editor and integrating new features will require the constitution of a real development team.


Guillaume Savaton