HPDZ.NET News

What's New

Take5

Take5 is an animation rendered way back in May 2008. At the time, the colorizing techniques available were not able to make an attractive production video due to the nature of the fractal data. Since then, a lot of work has gone into developing new colorizing methods, and last month's video, Project17, was the testing ground for a fundamentally new approach to this. Take5 uses a similar technique, with some modifications to remove some of the weaknesses of the previous approach.

This is a deep-zoom into a five-fold symmetric fiber of the Mandelbrot set. The accompanying music is a custom creation using Acid Pro 6 that has a 5-beat rhythm.

Details

Global Colorizing Revised

Project17 was the first video to utilize a new concept in colorizing fractal videos based on generating statistics of the entire video and finding an optimal mapping from counts to colors based on the cumulative fractal data in the entire video. This approach worked very well, especially considering how simple the software is.

Still, due to the use of a histogram in the Project17 method, some parts of the color mapping appear "flat" especially near the end.

The technique for Take5 uses the same global statistical approach as the colorizing for Project17 did, but it uses a rank-order map to convert fractal data to colors. This kind of map has been used extensively here in still images and in some dynamic color mapping schemes in other videos. It tends to preserve image detail better at the higher range of the fractal count data range than histogram methods do. Take5 looked much worse than Project17 with the histogram-based method, but it looks pretty good with the rank-order coloring used here.

Future work

Colorizing

Colorizing the fractal data has been one of the greatest challenges over the past couple of years that HPDZ has been publishing fractal animations. The method demonstrated in Take5 is the latest step in a long evolution of different approaches, and while it works well for this particular animation, it has its limitations. Experience is constantly teaching new lessons and inspiring new approaches. More complex techniques are in development, and better-looking videos are coming.

Frame Interpolation

This controversial and much-abused method for speeding up fractal animation rendering has been another area of active work at HPDZ, and it the subject of a Technical article on the web site.

The past month has seen some significant improvements in this technique that allow optimal master frame images to be identified for complex animations with simultaneous panning and zooming, as well as reverse zooming (i.e. zoom-out). This new phase of progress on this technique is still being finalized for production work, but it has huge potential to allow enormous speed-up of very complex "touring" type animations like SecantAnimation1.

For those who have a philosophical objection to this approach, the assurance that HPDZ will always maintain signal processing integrity by never undersampling images when this method is used bears repeating. In a deep information-theoretic sense, what we are doing with frame interpolation, when done correctly, yields the same usable video information as frame-by-frame rendering, at a fraction of the computational time.

The next project in the pipeline will utilize this new and improved frame interpolation technology.