Welcome to the AviStack homepage!

AviStack is a freeware tool for astronomy that registers, stacks and processes movies and image sequences.


Update of 01 March 2014: AviStack2 is no longer under developent or maintenance, unfortunately.

But, you are certainly welcome to still use it!


Update of 27 August 2013: French language files now included!

Thanks go to Laurent Zimmermann who translated AviStack2 into French.

If you have already installed AviStack2 on your computer, you won't have to download the full installation. Just download the language files and unzip the content into the folder "lang" which you can find in your AviStack2 directory. After starting AviStack2, select FRE from "Settings > Language" and confirm your selection. AviStack2 will then be restarted in French.


Update of 23 July 2010: Version 2.00 now available!

AviStack2 comes with a new look, is much faster than the old AviStack1.x and offers a whole range of new features. The most important of which is:

  • Fully automatic processing!

What else is new:

  • Pre-setting of all parameters possible.
  • Much faster alignment methods.
  • Automatic frame pre-selection by frame quality and/or brightness.
  • Use of flat-fields/dark frames throughout processing to reduce impact
    of imaging artifacts.
  • Enhanced post-processing module.
  • Creation of false color images.
  • Remembers GUI geometry from session to session.
  • User contributed XML language libraries.
  • A statistics package allows to analyse properties of your movies.
  • Write your own plug-ins for AviStack2 (in IDL).

AviStack is supported by CREASO GmbH



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From Version 1.80, AviStack enables you to read a wide range of file formats as well as AVI codecs (Windows only!). This is thanks to Ronn Kling's AVI reader DLL/DLM. It makes accessible basically all AVI codecs installed on your computer.

This is how to proceed:

  1. Download and install AviStack.
  2. Goto Ronn's homepage where you will find the DLL/DLM download.
  3. Click on "krsgravi" and download krsgravi.zip. Then unzip it.
  4. Place KRSgrAVI.dll and KRSgrAVI.dlm in your AviStack program directory.
  5. Run AviStack.

If you want to read MOVs (e.g. Canon DSLR HD videos) and MPEGs with AviStack, you will additionally have to install the AviSynth frame server. Ronn's DLL will then take care that most MOVs and MPEGs are read properly.



If you have any trouble/recommendations, please, give feedback via the AviStack Group or contact me!


Example Images

For example images, visit my homepage or look here.


Many thanks to everyone who was involved in beta testing AviStack2!

Michael Theusner