Avidemux Forum

I do have multiple versions of Avidemux installed,
so I renamed the Avidemux folder in %appdata%.
I also uninstalled all versions of Avidemux,
downloaded the latest current nightly of the ming64 version,
and reinstalled from that, and rebooted.

It did not fix the problem,
but I should now have a clean Avidemux install,
which is good.

TT don't use Mpeg-2 TS files anymore,
though I sometimes use AviDemux to
extract Mpeg-2 from MKV into an Mpeg-2 PS file.
I have not noticed any problems with that.

I have very little experience with Linux,
it is rather beyond me to do a cross-compile.
I can wait for the next nightly windows build, thanks.

I've updated MXE setup scripts and was able to test my own build off the latest git on Windows 11: "Save Current Settings as Default" works for me as it should.

If you have access to a somewhat powerful PC with a current Linux distribution (e.g. Fedora 44) and 10 GiB or more free storage space, I would recommend to cross-compile from source as described here (the description itself has not been updated but should work as-is).

At least the current git master works fine (on Linux, testing on Windows is not possible for me ATM) in this regard. From 2026-04-08 to and including 2026-05-29 is a very unfortunate time range as opening MPEG-TS streams with MPEG-2 video was broken.

If you don't need MPEG-2, it should be more or less fine function-wise. Can it be that you access the same Avidemux profile from different Avidemux versions? As configuration was changed on April 8, returning to an earlier build may be problematic. In doubt, please rename %appdata%\avidemux directory and retry with 260516.

The "Save Current Settings as Default" menu option no longer seems to be honoured for Video settings. In the next session Video resets to Copy, and the Config reverts to default values.

I am running Avidemux 2.8.2 260516_46963d075c1-fflibs 7.0.2  mingw 64bit
under Windows 11 on an Intel PC, with a local account.

I also have an old version that works fine in this regard,
on a Windows 10 AMD PC, with a Microsoft account.
Avidemux 2.8.2 250526_b008a4d098-fflibs 7.0.2-VC++

Quote from: Redcrest82 on July 16, 2026, 08:26:54 AM

Code Select Expand

Assert failed :0 at line 116, file F:
\jenkins\workspace\VS2019_no_import\avidemux_plugins\ADM_demuxers\Mp4\ADM_atom.cpp

Honestly, I would not expect a different outcome with a recent nightly, but still please try nevertheless with the most recent build from the folder with cross-compiled builds. It should dump a more verbose debug message to admlog.txt in %localappdata%\avidemux directory. The file might be slightly corrupted.

If the file still triggers this assert failure (an orderly termination of the application to avoid a condition not handled by the code), please provide the file via Mega, Dropbox, Google Drive (link share that doesn't require a Google account to access the sample) or an equivalent service.

Thank you for the reply eumagga.  That 2.9.0 was a mistake.  It should have been 2.8.2.  My apologies.  I must have been doing it wrong.  I just tried it again using the round Red X button to cut the section in the middle and was able to save the video correctly, without getting the error message.  Thank you for your help. 

Try using a more recent version of Avidemux

https://www.avidemux.org/nightly/vsWin64/

Hello,

The same file opens properly in other tools.

Error output is:
Assert failed :0 at line 116, file F:
\jenkins\workspace\VS2019_no_import\avidemux_plugins\ADM_demuxers\Mp4\ADM_atom.cpp

Please let me know how I can share the problematic MP4 file.
This post has restrictions in format and size for attachments.

Thanks in advance

Quote from: MacKenrick on July 15, 2026, 11:14:25 PMOn my Windows 11 computer running Avidemux 2.9.0,

Please clarify what "Avidemux 2.9.0" is and where you have got that from. The hint: there is no such (official) version. The last release was 2.8.1, meanwhile ancient, the development has slowed down on the way to 2.8.2 with relatively recent nightly builds being the best option for the purpose.

To trim the end portion of a video in copy mode in pre-2.8.2 nightly builds as well as in 2.8.1 release (cropping is something completely different: removing outer portions of the picture), set the A marker where the deletion should start, reset the B marker (if not already at the default position past the last frame), then press DEL (or "Edit" --> "Delete", or just click on the big red button in the center of the navigation bar).

I am unable to crop to the end of a video.

On my Windows 11 computer running Avidemux 2.9.0, I cannot crop to the end of a video like I can with the older Avidemux 2.8.0 on my old Windows 10 computer.  On the old 2.8.0, I move the slider to where I want to start the crop, select the Go To Next Keyframe, then select Set Start Marker.   I then select Go To Last Frame and select Set End Marker.  I then select Edit and Cut.  The entire last part of the video is cut out.  If I try that on the new 2.9.0 and try to save the video, I get an error message. This happens with every video I try to trim the end on.  The only way I can crop to near the end of the video, is to get to the point where I select Go To Last Frame, then select Go To Previous Keyframe, then select Edit and Cut.  This method leaves the very last few seconds of the video, that I do not want, still on the saved video.

Why doesn't the newer 2.9 version of Avidemux allow me to cut to the end of the video?  How do I fix this problem?  Thank you for your help.