Any decent MP4 muxer with GUI?

[Bencuri]

I can't believe that I don't find a decent MP4 muxer. I used Yamb before, but for years not it has reporting various errors all the time. For a while it was missing MP4 box, I don't understand how it can go missing all the time. Now it is missing some other file, always has some problems. I downloaded the software called MP4Muxer.exe. Seems to be okay but can't open .mp4. It only opens video only formats that I never heard of and don't know how to generate, for example: .h264. How do you make that file??? Than I found MP4 Tool, but that one always reports a strange error. It is trying to use some temp file in an AppData folder, but reports it is being used. Even if it is the only software open.

I am becoming tired about these. Any one knows something that works as smoothly as MKVToolnix?

[davexnet]

.h264 is the elementary video stream, usually found in mp4 or mkv containers.
For what you are trying to do, I normally mux all the ingredients with mkvtoolnix,
then open the new mkv in Avidemux and change container to mp4.
This works fine, as long as the elements are compatible with mp4.

EDIT - Avidemux tends to ignore subtitles; perhaps a better method is a simple batch file using ffmpeg

[Alex_ander]

My Mp4Box GUI - not as old as YAMB (it's from 2013) and accepts other file types as input. Has mux/demux/cut functions. Doesn't work with new mp4Box builds, however. Works in Win10/11 without a problem.

[ProWo]

Use clever FFmpeg-GUI.
Load your file, click main, click multiplex, add what you want (video, audio, subs) or leave the source only, set mp4 as container, click multiplex.
Done.

[videoAI]

try https://www.videohelp.com/software/Video-to-Video-Converter

[Bencuri]

I checked the ones that you included, also others. They seem to behave differently sometimes.

It is best noticeable when you mux mp4 with ac3. I downloaded the latest Yamb, it works (I noticed the missing mp3box was the problem, even if it did report another kind of error). But it gives the worst result: the playback is fluent, but when you jump to various points on the timeline, a momentary slowing down in the video playback happens. MyMp4Box and MEGui is significantly better, when you jump first that slowing down happens, but then it doesn't any more. I found (for some odd reason), that the best is this one: https://www.videohelp.com/software/MP4-tool. With this one the video plays and jumps fluently. I always select l-smash in it as muxer, maybe because of that.

If you convert the ac3 to aac befor muxing, these problems when jumping doesn't happen. All seem to work fine. Ac3 is not a standard mp4 audio format as I know, but they always say try to avoid reconverting, so I always try to leave the audio as it is.