Any functional muxer for MP4?

[Djard]

I realize I can't expect too much from freeware, though there are excellent ones, like VirtualDub. So I'm more than willing to pay for an app if it can actually do what it claims to be able to do. I need to demux and mux MP4 files, which seems to be quite a challenge for software developers. So far, every app I have tried for this purpose came up short.

tsMuxer in my opinion is not worth installing: it demuxes
an MP4 to .264 file extension. After I edit the audio file, keeping the original format, tsMuxer almost always renders a soundless file. If subs are involved, the problem is compounded. So I convert the .264 to AVI and use Virtualdub to mux the project. The extra step of recoding also lowers video quality.

Surely there is something out there that can actually separate audio from video--without messing up the video format--letting me edit the audio file, and then muxing the two files. Or are we limited to AVI and VD?

I've had well-meaning people recommend crapware, so I'd be grateful for advice only from folks that have used the software they might recommend and succeeded in getting it
to work properly.

[nhakobian]

You're using the wrong tool for the task. tsMuxer, is *not* an MP4 muxer at all. As the name suggests, it is a ts (transport stream) muxer/demuxer.

The two most used MP4 muxers are MP4Box (part of the GPAC project, which is the "official" MP4 release) and L-SMASH. Both work very well, and there are even GUIs for MP4Box if you do not like working on the command line.

Doing a google search also helps, just as a test I put in "mp4 muxer" and got a number of results, including the tools I mentioned above.

[Blue_MiSfit]

^^ mp4box and L-SMASH are commonly used. ffmpeg / libav can do what you're looking for as well.

[Djard]

tsMuxer was recommended to me for the purpose I described at another forum. Maybe I misunderstood.

Still, I believe I'm more likely to have success by leaning on the experience of others who are willing to share their knowledge, rather than randomly Googling for software. Some of the apps touting the ability to demux MP4 video files that I tried made me wonder why some developers release software that doesn't work. It just tarnishes their name. I'm not alone in this matter as I've seen many posts to this effect.

I downloaded and install GPAC's MP4Box and the GUI. Oddly the Osmo4 and other extras that I unckecked installed anyway and tried to communicated with an Internet site, but my firewall blocked it. But no worries. Thanks again for steering me in the right direction. I'm grateful.

[ty2010]

MP4s have been as much of a PIA as putting together VOBs. Lately I've been mostly using mkvmerge to get everything together then remux with ffmpeg.