Avidemux Forum

Quote from: JanMeki on October 27, 2026, 02:31:41 PMIt says Display: RGB on the status bar.

This means that VDPAU display is not available.

Quote from: JanMeki on October 27, 2026, 02:31:41 PMDon't know why the intel decoder is not detected

Probably due to mismatch between the build and the host environment or due to another reason – please redirect stdout and stderr of appImage to a file and attach it to your reply here or post it on some pastebin equivalent as far as that service doesn't require login.

./relative/path/to/appImage 2>&1 | tee path/to/admlog.txt
Please replace paths containing personally identifiable information in a consistent way with placeholders prior to uploading the log.

Quote from: JanMeki on October 27, 2026, 02:31:41 PMEdit: Seems like Xvideo is the only video display mode that doesn't stretch the video frame. Is that the best one to use in my situation?

Yes, sure.

Quote from: JanMeki on October 27, 2026, 02:31:41 PMShould I use hw acceleration with that one?

As long as a closed-loop hw accel (libva hw decoder + libva display or VDPAU decoder + VDPAU display) is not available, NVDEC will always be beneficial. Therefore yes, use NVDEC then.

Quote from: JanMeki on October 27, 2026, 02:31:41 PMOpenGL makes the avidemux ui unusable (garbled) so that's out of the question.

Could you please eventually do build Avidemux locally to have a clear picture of what works and what doesn't?

I've been using video display: vdpau under display in the settings and nvdec under hw accel because it's the only one available (vdpau and libva are grayed out). It says Display: RGB on the status bar. Don't know why the intel decoder is not detected (I can use it in smplayer). This is on Skylake / Maxwell so there is no VP9 decoder and only the iGPU does h265 Main decoding. Maybe it's better to have hw acceleration off instead if multithreading is beneficial for VP9, h265 adn AV1? What are the optimal settings for my situation?

I don't see any difference capping the refresh rate of the gui. I feel like the scaling thing is the problem because if I use zoom 2:1 it plays in slomo and for every 1 sec the video is late by another 3000 ms.

Edit: Seems like Xvideo is the only video display mode that doesn't stretch the video frame. Is that the best one to use in my situation? Should I use hw acceleration with that one? OpenGL makes the avidemux ui unusable (garbled) so that's out of the question.

Quote from: JanMeki on October 25, 2026, 11:44:21 AM

Code Select Expand

/tmp/.mount_AvidemmePfkG/usr/bin/avidemux3_portable: symbol lookup error: /tmp/.mount_AvidemmePfkG/usr/lib/libgobject-2.0.so.0: undefined symbol: g_sort_array
/home/abc

My best bet would be recommending you to build Avidemux from source locally on your system (which is very easy on Linux, see github.com/mean00/avidemux2) so that libraries included into the appImage don't clash with system libraries.

You don't need to package and install Avidemux to run it, it can be excuted via a wrapper script (all explained in the README).

If the Avidemux window can't fit into the available screen real estate, Qt may distort the frame used to draw the video at least with the unaccelerated "Qt" video display if I am not mistaken. Avidemux won't add scroll bars to video frame, selecting zoom level too high will at least try to push parts of the GUI out of sight. If your (presumably) laptop has a high-density display, you might also consider disabling automatic HighDPI scaling in Qt, e.g. by setting the env var QT_SCALE_FACTOR to 1:

QT_SCALE_FACTOR=1 ./relative/path/to/Avidemux-x86_64_20261018_legacy.AppImage

Make sure you use an accelerated video display in Avidemux, i.e. NOT "Qt" / "RGB", preferably VDPAU (but with the graphics wired to Intel this might not work), OpenGL / QtGl or XVideo, else all the scaling work is done on the CPU. The best options are to use VDPAU hw decoder with VDPAU display or LibVA decoder with LibVA display (whatever works). If NVDEC is used, it always downloads decoded pictures to the main memory that need to be re-uploaded to the graphics card for display. This may still be beneficial, but not as efficient as it can be.

Another huge cause of lag can be the status bar itself, especially at 60 fps. Try hiding it via the "View" menü or restrict refresh rate of the GUI in Avidemux Preferences to a lower value e.g. by enabling the cap and setting the redraw interval to 20 ms (1000/20 = 50 fps) or higher.

Already when playing 1080p60 videos (h264) I'm getting this problem sometimes. It may have something to do with scaling, because when I use a zoom level of 1:4 or 1:2 I never get the issue but already when using fit to window (65%), 1:1 or 2:1 I'm getting major A/V desync. When opening a 1920x1080 video the zoom level is 69% but if I change it to fit to window, which is 65% I'm getting desync again. I've tried with and without hw acceleration enabled (nvdec). I'm not maxing my hardware, I've got plenty of CPU, dGPU, iGPU left.

Usage:
CPU: 15%
iGPU (Render/3D): 35%
dGPU (if used): ~5%

I can play 4k60 h264 videos fine with smplayer/mpv.

Linux Mint 22.3
Avidemux-x86_64_20261018_legacy.AppImage, Avidemux-x86_64_20260516_legacy.AppImage, ...
Intel/nVidia Optimus
1920x1080 display

If I set the zoom to 1:1 when viewing a video it stretches the video instead of zooming it (it fills the viewing area with a wrong aspect ratio). 1080p video on 1920x1080 screen. Fit to window is 65% zoom and correct AR.

Linux Mint 22.3
Avidemux-x86_64_20261018_legacy.AppImage

Quote from: eumagga0x2a on October 21, 2026, 12:25:36 PMJust curious, why the legacy one? Does the normal appImage that requires libc (glibc) 2.38 or later fail to run (as it does on Debian 12 due to libc version being too old)?

I'm on (Ubuntu GLIBC 2.39-0ubuntu8.9) 2.39

This is what I get if try to run the non-legacy appimage:

$ '/home/abc/Apps/Avidemux-x86_64_20261018.AppImage'
Using bundled freetype, fontconfig and fribidi. Export ADM_APPIMAGE_USE_SYSTEM_FONT_LIBS=1 to use the system ones instead.
This is recommended for systems with fontconfig >= 2.13
/tmp/.mount_AvidemmePfkG/usr/bin/avidemux3_portable: symbol lookup error: /tmp/.mount_AvidemmePfkG/usr/lib/libgobject-2.0.so.0: undefined symbol: g_sort_array
/home/abc

You are correct. Had to add the folder as an exclusion in Windows Security.
In case anyone runs into the same issue, these are the steps:

1) start Windows Security
2) click Virus & threat protection
3) on the right side under 'Virus & threat protection settings' click "Manage settings"

You cannot view this attachment.

4) scroll all the way down to 'Exclusions' and click "Add or remove exclusions"

You cannot view this attachment.

5) click Add an exclusion

You cannot view this attachment.   

6) select "Folder"
7) browse to the correct folder and select it

Quote from: Yisc76 on October 23, 2026, 10:02:22 AMThen I needed it yesterday and the program just won't launch. Had to stop de proces using taskmanager and then it does start, but goes to "Not Responding" immediately. I left it sitting as I had to go and do thing else and when I came back to the computer, I was responding and I could use it fine.

For sure antivirus, probably Windows own built-in one, (re-) uploading every DLL dynamically loaded by every one of numerous Avidemux plugins (almost everything in Avidemux is a plugin) to the mothership and waiting for response. I doubt that anything can be done about it except for adding Avidemux program folder to path exclusions in Microsoft Defender or its equivalent.

You can check whether this is really the reason for the issue by temporally moving (almost) all Avidemux plugins (maybe except for demuxers and most necessary muxers) out of Avidemux program directory.

edit: please see https://avidemux.org/smif/index.php/topic,20186.msg95347.html