Welcome the Siril Project!

A new FL/OSS project has joined us here! After some heroes stepped up to the plate a couple of days ago to provide flatpak builds (thank you so much @paperdigits and @julian!) they decided to have their forums hosted here with us.

Please welcome the Siril team! (For those not familiar, it’s the Free Astronomical processing project that @sguyader wrote up an awesome tutorial for recently.) The developer from the project is @lock042 - so stop by and say hello if you get a chance!


Welcome @lock042 and company! I hope we can be of service.

Actually someone on Twitter saw the flatpak request and made it quick… I didn’t do anything :slight_smile:


Thanks a lot for having us here! I’m the other developer of siril. Cheers!


Hello. Thank you very much. It is a real pleasure to be hosted here between great software like, GIMP, darktable, rawtherapee, and many others.
I would like to thank the community for their help and especially @julian that will help me to build the CI of the flatpak. Indeed, building the packages is maybe the darkest side of the software development. First, Siril was only developed for GNU/Linux as @vinvin and I are only Linux user. However, last years we tried to make Siril available for macOS and Windows.
Recently, I did manage to build a nice dmg bundle with a script that do all things automatically. So the next version will have a nice dmg :).
For the windows version, it is less smooth. I compile the all app with msys2 (on a VM) and copy the dlls by hand to a bundle. But it works :). It is just much pain.
If I’m writing all these things it is because @patdavid told me that some guys on this website are really good for packaging and that I should ask for some help. So if there are some volunteers for helping us for windows packaging for example (next release is not yet, so no rush at all), that would be great. If not, I hope that some of you will enjoy using Siril in the same way we are enjoying developing it.

Clear skyes.


Welcome! I use Siril often for image stacking - although I use it for somewhat “nontypical” (non-astronomical) applications.

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It’s also quite good at extracting frames from films :wink:

ping @gaaned92


@lock042 Welcome! I don’t use Siril but I appreciate what goes into it and the results that come from it.

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The next version will be the 1.0.0. As on every project, the 1.0.0 is a bit special. Indeed, we have decided to improve a lot of weakness in Siril.

  • We will handle the 32bit per channel precision (really needed in astronomy)
  • The UI has totally changed. Even if I’m not a GTK expert, I’ve tried to design something better. Here the comparison of the 0.9.12 (current version , with multiple windows) and the new 0.99.0 (that is the dev version of the 1.0).
    v 0.9.12:

    v 0.99.0:

Changes are big :).



I’m one of the other members of the Siril development team and I’m in charge of the documentation, made with the opensource software “Dokiel” and of the siril.org website.

Like Cyril, I’m very proud to join you.

I’m currently actively working on the complete redesign of the documentation with the coming new features of the next version of Siril.

I will probably add a part on the possible use of Siril in other fields than astrophotography for example the uses that can be made in photography of the different types of stacking available in Siril.

Clear Skies,



Alright then, I guess I’m starting with astrophotography now!
Thank you all so much for your work!


Great news! Welcome Siril devs!

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I am here!
Welcome SIRIL team!
My last dev activity dates from 1989 so I am not proficient in dev tools (configure,Cmake, windows CI, . . . ) and in coding. I am only trying to give back some help to the community.

I tried to build on W10. The compilation of the SIRIL source is OK. The difficulty comes from the dependencies. The list is quite long.
seems ok except a problem with libx264


I have only libx264-159.dll ( package mingw-w64-x86_64-x264-git r2991.1771b556-1) in mingw64/bin.
libx264-157.dll is called by avcodec-58.dll (mingw-w64-x86_64-ffmpeg 4.2.2-1)
So the two packages seem incompatible.
What do you recommend? I can revert mingw-w64-x86_64-x264-git but to which version?

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Hello @gaaned92, Thx for your message.
This dependency is a also dep of libheif. Libheif is not mandatory for Siril. Maybe this is the issue?
Maybe that is an issue we could submit to MSys2. Conflict between libheif and avcodec.
On my VM, I believe I don’t have libheif.

I will check when back home.

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heif is using h.256/hevc and not h.264

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I get the same error as @gaaned92 though without having libheif package installed

Hum … Strange. My VM is not up to date and this is probably why everything is going well on it. So I will wait before updating msys2 :).
In a first step, ffmpeg is not mandatory too, even if in a finale package it is better to have all dependencies.

libbx264 is called only by avcodec-58.dll.
avcodec and libx264 are part of the ffmpeg project
see https://github.com/FFmpeg/FFmpeg/blob/master/libavcodec/libx264.c
but are built separatly in mingw64

It happens that mingw-w64-x86_64-ffmpeg was built the 2020-01-08 18:46:18 and the dependency mingw-w64-x86_64-x264-git was built the 2020-01-17 08:22:53 and effectively provides /mingw64/bin/libx264-159.dll
That can explain the issue. Where a mingw64 package bug report should be written?

I am going to downgrade x264 to mingw-w64-x86_64-x264-git-r2970.5493be84-1-any…>
That could be ok waiting for an update.


Now it starts but I have issue with the GUI

If I hover over the Siril window, some widgets appear. But icons are missing.
surely subdirs with icons, GTK files … are missing or misplaced.

The upper window part is transparent and missing Windows decoration.

To test and help, you can upload install.zip at

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