Reprojecting equirectangular images for a printed presentation – Scripts

During our talk about “Reprojecting equirectangular images for a printed presentation” in Palmela and Vienna we presented two scripts you can use to reproject images using a so called Droste – effect. See some examples in these posts.

Here is a short overview over the software we used, you can consider this as the required runtime environment for the scripts:

Software Version Platform
The Gimp 2.6.11 Windows; Linux; Mac
Mathmap Plugin for The Gimp 1.5.3 Windows; Linux; Mac
Adobe Pixel Bender Toolkit 2.5.449694 Windows; Mac

One of these is a script for the Gimp’s Mathmap Plugin. The other one is a script for the Pixel Bender Toolkit. The problem with the original two scripts is, that the parameters they use have different names and they are implemented differently! E.g. sizes are pixel sizes in one script and percentages of the image size in the other script. I wanted to be able to use the same parameters in both environments. So I started to bring the scripts back together.

The main motivation for this was to be able to work on large files. The Pixel Bender stand alone version has a size limitation depending on your graphics card. This may be a maximum of 2048×2048 pixels or like in my case 4096×4096 pixels. When you want to process larger images you have to switch to The Gimp. These size limitations do not apply there! The Mathmap rendering on the other hand is really slow compared to the Pixel Bender. This is because Mathmap renders the final image and the preview on a single core of your CPU. The Pixel Bender toolkit renders both on the GPU!

This table shows links to the original scripts (Mathmap V10 and Pixel Bender V1.1) and the modified versions with exchangable parameters (Mathmap V11 and Pixel Bender V2).

Script (Download link) Version Link
Droste for Mathmap (Original) V10
Droste for Mathmap (PixelBender compatible Version) V11 This article
Droste for PixelBender (Original) V1.1 Homepage
Droste for PixelBender (Mathmap compatible version) V2 This article

See two screenshots of some sample settings using Mathmap and Pixel Bender and the original and transformed image:

For an example workflow on how to generate a Droste spiral effect from a 360° panoramic (or equirectangular) image image read this post.

Acknowledegements go to the following persons, who started the first versions of the scripts: Mathmap: breic, Josh Sommers; Pixel Bender: Tom Beddard
You find further information about the Math behind the Droste effect here and here

Related Posts
An article describing in five easy steps how to embed an equirectangular using Google Views.
READ MORE
This is a Pecha Kucha presentation about reprojecting equirectangular images.

READ MORE
This panorama shows the Hotel São Filipe in Setúbal in the morning mist.

READ MORE
This panorama shows the view from the summit of Haytor.
READ MORE
This panorama shows the interior of the Roland Levinsky building.
READ MORE
The Maritime Museum has been established in 1873 by Prince Henry of the Netherlands. Sometimes it is also named after its founder: Prince Hendrik Museum. Prince Hendrik himself had a naval career.


READ MORE
This years PanoTools Meeting took place in Messina, Italy. This panorama shows the meeting venue on the first day, short before the meeting started.


READ MORE
Piața Unirii is a central place in Timișoara, Romania.

READ MORE
This panorama shows a view from the terrace of the Roland Levinsky building.
READ MORE
Five easy steps to publish a spherical panorama
Reprojecting equirectangular images
Pousada de Setúbal; Hotel São Filipe
Gala dinner at the Interational Panoramic Photography Festival
Haytor Summit
Plymouth University Roland Levinsky Building
Cranes in the Maritime Museum in Rotterdam; The
PanoTools Meeting 2013 Messina Sicily Second Impression
Piața Unirii in Timișoara, Romania
Plymouth University Roland Levinsky Terrace

Author: PanoTwin Markus

PanoTwin Markus → My Google+ Profile

2 thoughts on “Reprojecting equirectangular images for a printed presentation – Scripts”

Leave a Reply

Your email address will not be published. Required fields are marked *