Natron (software)

Natron

Original author(s)	Alexandre Gauthier, Frédéric Devernay
Initial release	October 22, 2014
Stable release	2.0.1 / March 18, 2016 [1]
Development status	Active
Written in	C++, Python, Qt
Operating system	Linux, Windows, OS X, FreeBSD
Type	Node-based compositing software
License	GNU General Public License
Website	http://natron.fr/

Natron is a free and open-source node-based compositing software. It has been influenced by digital compositing software such as Nuke, from which its user interface and many of its concepts are derived.

Natron supports plugins following the OpenFX 1.4 API. Most open-source and commercial OpenFX plug-ins are supported.

Origin of the name

Natron is named after Lake Natron in Tanzania which, according to Natron lead programmer Alexandre Gauthier provides "natural visual effects" by preserving its dead animals.^[2]

History

Natron was started by Alexandre Gauthier in June 2012 as a personal project. The project was the winner of the 2013 Boost Your Code contest by Inria. The prize was a 12-month employment contract to develop Natron as a free and open-source software within the institute.

The first widely available public release was 0.92 (05.06.2014), which brought rotoscoping and chroma keying functionalities.^[3] Subsequent beta releases brought additional features such as motion blur, color management through OpenColorIO, and video tracking.

Version 1.0 was released on 22.12.2014,^[4] together with a large sample project by François "CoyHot" Grassard, a professional computer graphics artist and teacher, demonstrating that Natron could execute interactively graphs with more than 100 nodes. In January 2015, the Art and Technology of Image (ATI) department in Paris 8 University announced that they would switch to professional-quality free and open-source software for teaching computer graphics to students and artists, including Blender, Krita and Natron.^[5][6]

Licensing

Before version 2.0, Natron was licensed under the Mozilla Public License version 2.0, which allowed redistributing it with closed-source plug-ins.

Since version 2.0, it is now distributed under the GNU General Public License version 2 or later. All plugins that are distributed with binaries of Natron 2.0 or later have thus to be compatible with the GPL. Closed-source plug-ins, including commercial ones, can still be used with Natron, although the GPL theoretically does not allow loading and linking closed-source plug-ins,^[7] or plug-ins that are not distributed under a GPL compatible license, but they have to be distributed separately.

Blender, another open source software which can be used for digital compositing, also uses the GPL license.

Data produced by Natron, or any software distributed under the GPL, is not covered by the GPL: the copyright on the output of a program belongs to the user of that program.

Features

Natron has the following notable features:^[8]

• 32 bits floating point linear color processing pipeline: all frames are represented as floating-point RGBA samples with premultiplied alpha,^[9] permitting the use of alpha compositing operators defined by Thomas Porter and Tom Duff.^[10]
• Support for multi-core architectures: all processing is multithreaded using a thread pool pattern.
• Color management is handled by the OpenColorIO library, including support for the ACES color encoding system proposed by the Academy of Motion Picture Arts and Sciences.
• Support for stereoscopic 3D and multi-view processing.
• Support for many image formats, using OpenImageIO, including multi-layer OpenEXR. Additional image layers can be used to store several color layers, or for non-color information such as depth, optical flow, binocular disparity, or masks.
• Support for reading and writing video files through the FFmpeg library, including digital intermediate formats such as DNxHD and Apple ProRes.
• Full support of the OpenFX 1.3 API, enabling use of open source or commercial plug-ins.
• Low hardware requirements: a 64 bits or 32 bits processor, at least 2 GiB of RAM, and a graphic card that supports OpenGL 2.0 or OpenGL 1.5 with a few commonly available extensions (ARB_texture_non_power_of_two, ARB_shader_objects, ARB_vertex_buffer_object, ARB_pixel_buffer_object).
• Support for low-resolution rendering for previewing the output of computing-intensive visual effects.
• Support for batch-mode rendering through a command-line tool, allowing the final render to be processed on a render farm.
• Manual rotoscoping, using Bézier curves
• Key frame-based parameter animation, using Bernstein polynomials (the polynomial basis behind Bézier curves) for interpolation.
• Video tracking functionalities.
• A project format written in XML and easily human editable.
• Node presets can be imported/exported easily via XML.
• A wide range of additional effects (color transforms, geometric transforms, image generators...) are available.

Version 2 Features

Version 2 of Natron adds several major features:

• Python scripting: Natron has made available via its Python API most of its functionnalities.^[11]
• Multi-plane: In Natron all layers read from EXR’s are available as planes that each node can access. You can also freely create your own custom planes. This allows for cleaner graphs and more efficient work.
• Composite plugins, called PyPlugs, editable through the GUI or in Python. These composite plugins are presented to the user as a single node with a set of parameters, but contain several nodes arranged in a subgraph.

External links

• Natron website

References

1. "Release 2.0.1".
2. "Image Album: Lake Natron Gives Up Its Dead | Rick Brandt". livescience.com. Retrieved 2015-05-25.
3. "Natron v0.92 beta is out! – Natron". natron.inria.fr. Retrieved 2015-05-25.
4. "Natron 1.0 brings free VFX compositing to Linux, Windows, Mac users | Libre Graphics World". libregraphicsworld.org. Retrieved 2015-05-25.
5. Krita Foundation. "‘Goodbye Photoshop’ and ‘Hello Krita’ at University Paris 8 | Krita". krita.org. Retrieved 2015-05-25.
6. "The complete story of Paris-8 university going for Krita, Blender, Natron | Libre Graphics World". libregraphicsworld.org. Retrieved 2015-05-25.
7. "Frequently Asked Questions about the GNU Licenses - GNU Project - Free Software Foundation". gnu.org. Retrieved 2015-05-25.
8. "Features & Roadmap – Natron". natron.inria.fr. Retrieved 2015-05-25.
9. http://home.comcast.net/~tom_forsyth/blog.wiki.html#Premultiplied alpha
10. Porter, Thomas; Tom Duff (1984). "Compositing Digital Images" (PDF). Computer Graphics 18 (3): 253–259. doi:10.1145/800031.808606. ISBN 0-89791-138-5.
11. "Welcome to Natron Python developers guide — Natron 2.0.0 documentation". natron.rtfd.org. Retrieved 2015-05-25.