I looked for answers but am not sure I found a good one or best for needs. I often have a video presentation which I need to only fix the audio. In the past I’ve imported the entire video into Vegas and then rendered. I assume that each time I re-render the file it re-encodes the entire video and audio. I think avidemux had a process where you could specify whether to touch or leave either half, e.g. process the audio from ac3 to mp3 but leave the video alone so I assume it processed the audio and remuxed it to the video and created a new file in whatever container you wanted, e.g. mp4.
What I’d have preferred is for Vegas to either know or for me to give the option that if the video isn’t edited at all (or checked to ignore edits) that it would re-encode the audio and then package the video synced with the audio into a new container/mp.4 file.
1) Is there a way to make this happen in Vegas?
2) Is there any simpler way other than having to use some other program or utility to demux files, if you can file the right tool, and then edit the audio separately and then use that other tool to remux the video (hoping you’ve got a tool to do that and has tools to move audio back and forth)?
1) No. There is no way to do this inside of Vegas.
2) Yes. This can easily be done outside of Vegas using either paid or open source software. By far, the best is FFmpeg which is more or less the Swiss Army Knife of video/audio editing. The downside is that it’s a Command Line app which requires a bit of a learning curve. Paid apps would include such software as VideoRedo or TMPGEnc’s MPEG Smart Renderer, both of which will do smart-rendering in addition to simple re-muxing. They also have a nice UI that makes it pretty easy. The downside is cost.
If you want to try FFmpeg, I can provide you with an example CommandLine that will do what you want. Here is a link for the free download. https://ffmpeg.zeranoe.com/builds/. Just make sure that you choose the 64bit version. Like most everything else, it’s pretty simple “once you know how”.
Thanks – very much appreciated. I’ll add one more to the list I’ve been using and guess I’ll continue to use and perhaps might investigate some of your suggestions. My MP4 Box does muxing, demuxing and joining files. Works well.
In case you’re still interested, I just finished a standalone app that might do exactly what you want. I originally wrote it just to correct for audio sync problems in MP4 renders that make use of apps like Handbrake or Voukoder inside of Vegas, but expanded it to enable the user to replace the audio stream from the original file with the audio stream from a replacement file. No re-rendering–just copying and remuxing. Here’s a screen grab.
Its a free tool that can be downloaded here. https://tools4vegas.com/library/ Note that it does require installation of ffmpeg which you probably already have. Just make sure the executable can reached from the user path variable in Environment Variables.
Re your post on May 17, 2020 at 2:08 am where you mention your new tool, can it work with Macintosh? I’m not a Windows user nor have I any experience with command line.
I’ve been downloading vids from a TV broadcast overseas, but when I trim the beginning and end with Quicktime, it throws the audio out by up to 2 seconds, so i’ve had to correct and re-encode using VLC record. The video clarity is not really noticeable but it’s very time consuming.
I thought I could do this using Apple’s iMovie but couldn’t work out how to use it. Bit of a dumb blonde, I’m afraid!