Natron

Natron is a free video creation and editing software, that is really efficient and under public license. It can be used on MacOSX, Windows and Linux.

We can use it to create a video that can be displayed in hologram.

Installation

  1. Follow the installation instructions for Windows, MacOSX and Linux.
  2. Download the project file for the prism or the focus

Open the downloaded project.

natron openning screen "Prism" project once opened

Use

Overview

The given project file contains many transformations (in orange) and masks (in blue) set up to produce the final hologram. It was made with default settings to realize the final hologram without technical knowledge in video editing.

The principal elements in the “Node Graph” part that will be used :

Import a video

The first step is to import a video. You have to create a new Node in the “Node graph” part. Just drag and drop a video in this zone.

Node graph The "Node Graph" zone

You can also right click, choose Reader in the section image (Shortcut : R), or use the default shortcut R.

It creates a “Reader node”. You must link it to the ‘position’ node in order to place the video correctly.

reader node Create a link between 2 nodes

Optimize the rendering

Some settings are necessary to have the best render. These settings are to be made on the transform Nodes of the scene. Either manually in the preview, or in the “Nodes” configuration tool for more precision.

Activate the Transform node by clicking twice on it. A positionning and scaling icon should appear in the Viewer2.

resize a node Scale the object for it doesn't go out of the black triangle.

Use the Viewer2 to better see the outlines. Your video must entirely be in the black part. Do not hesitate to play the video to verify that the object doesn’t go out during the whole animation.

natron preview for transformations Click on the center of the cross to move it, or on the circle to scale it
transformations properties Use the X, Y translate function to move it, or Scale to scale it

Once you are happy with the positionning, you can see the final result by clicking on Viewer1.

Render the hologram

Now you just need to export your holographic video. In the Properties zone, find the element WritePNG, or WriteVideo and then click Render.

  • WritePNG creates a sequence of picture numbered files frame-<1-500>.png that you will encode with any video editing software. It is the more flexible way to export your work
  • WriteVideo will directly encode the video for you. The codecs that Natron uses are sometimes unstable, it is generally safer to use a second software that encodes better.

To sum up, WritePNG is preferable, unless you don't have access to any editing software.

The rendering can take up to 10 min for a video, depending on the computer that you use.
You can then transfere the video on your product.

Media transfert guide
render node properties
Properties of the "render node"