Visualization

In scientific areas visualization plays a big role for the interpretation of data which come out of experiments. These data have to be represented to the user (e.g. physist) in a way that she/he can obtain useful information. The most simple way is to display data in a diagram. But what will you do if these data depend on more than two variables? Than you will have to use some other type of representation e.g. a coloured output or maybe a movie. Although you can't read all data at one time, you have to select a certain set of data to represent. Then you have the problem to get fast access to the still hidden data. Normally you would take another sheet and create a new diagram which will cost you several minutes of your expensive time. So why not using concepts of the virtual reality and object oriented programming to represent data. This will give you the possibility to ask the data to represent themself and will keep you much time.
These things will be part of my PhD project at FZ Rossendorf.

Making videos

At FZ Rossendorf there is the possibility to create computer animated videos on VHS/S-VHS tape. Creating a video one has do two steps:
  1. Create a sequence of frames as TARGA (.tga) files
  2. Compose this sequence into a motion JPEG
The tool for creating the MJPG is called tga2mjpg and is available on ikon.fz-rossendorf.de. Where, as additional hardware a Parallax-Video overlay board, a S-VHS video recorder and a TV-set are installed.
For further question about it refer to the Visualisierung / Graphik page at FVTK.
What I tried out is creating a MJPG from a sequence of Windows Bitmap files. Which I created by using an one-line-call to a function which is able to store an array over [0,255] into a BMP file. The next step, creating a TGA sequence was done by the convert tool.
The module which contains the function is available by clicking here.

I also wrote a small Video Creation Tool which allows the user to specify a storie-book, looking like

  resolution 512 384
  framerate 10
  still "test.bmp" for 2
  blend linear from "black" to "fzrlogo.bmp" in 1
  still "last" for 2
  blend linear from "last" to "black" in 1
  blend linear from "last" to "title.bmp" in 0.5
  still "last" for 3
  end
and generate a MJPEG film as well. The tool allows blending, still-pictures and insert-cut.

Visualizing data within an application

For several reasons it is usefull to do visualization during the run of an application. Achieving this issue can simply be done by using some simple constructs, e.g. as it is done on the IBM PC when using Borland Products.

The simple graphics interface as specified by Borland is now translated into X11- and Open/GL calls. Nearly 70 % and all main functions are compiled within one library with only a few additional calls like flush(). The library is just a very simple interface to somewhat standardizised libraries. But generates results very fast.

The library contains functions for

The library supports only one graphics window. A very simple program looks like

source 











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