Would someone please tell me how this is done?

As many of you probably are aware there are many videos out there on Youtube that include actual movie footage with the voices actors edited out to substitute their own voice content.

As an example to best understand what I am asking: if you search 'Darth Trump' on Youtube - In this video someone took actual movie footage and somehow used their own voice clips (of Donald Trump) for Darth Vader's voice to create a rather comical spoof.

Please keep in mind I am not asking this so that I can break any copyright rules but I would like to learn how to do this to make my own. Apparently this video isn't breaking any copyrights.

What techniques are used or what audio editing methods are required to make this happen? I am new to video editing although I did some research on this before deciding to post this questions. Apparently there is a way to strip the audio from movie file that has 5.1 audio and isolate the 'center channel' in portions of the movie by cutting it out and cross fading in your own audio. I read about it being possible with Audacity but I couldn't make sense of it.

Then I read about the term 'demux/remux' where you would use a program to separate the audio tracks. It is all very confusing - although I have been pretty determined to try and understand how it works.

Thank you for any assistance with this. I hope this is the right place to ask.

Some answers are here:

https://www.quora.com/How-do-you-remove ... in-a-movie

Basically, it hinges on 99% of most movie dialogue being in the front center channel. You can't always rely on this, because some filmmakers like to pan dialogue left and right when the actors move around in the frame, but it might work in the case of Star Wars.

That's what I thought. How do you isolate it in a video editor so you can manipulate it?

I spent 4 hours last night researching this on my own and found a way to simply isolate the channel with dialog (actors voices) from the background (sound effects, music etc) in Audacity by importing it as an .mkv. The file was a .VOB file and I had to convert it to MKV to do this. Initially I tried doing this with VLC media player but it would not preserve the 6.1 channels.

After downloading several 'free' video converters (that actually were not really free) I found one that would convert the .VOB footage I wanted to a .MKV (with a water mark as I did not want to pay $59.95) however I only wanted the audio so I will make my edits to the voice dialog channel and then export it and attempt to match it up with the video.

I am still open to finding many other ways to do this and would like to know if there is a 'free' .VOB to .MKV converter that is REALLY free. Converting from a VOB to an MKV (to just edit the audio in audacity) seems to be the simplest way I can come up with. I am hoping this will work and that I can simply match up with the audio with the video in a video editor like Davinci Resolve that I am using now.

So the workflow plan up to now is:

1. Mount DVD or BluRay Disc after ripping it into an image file to the hard drive
2. Locate the desired footage from the mounted image (.vob file)
3. Convert .vob to a .mkv
4. Import a copy of this .mkv into a video editor (muting the audio)
5. In Audacity preferences set import export settings to 'Custom Mix)' (of course this assumes you have already installed FFMpeg 2.2.2 for Audacity).
6. Import (the original exported .mkv) it into audacity - it will import each channel into a separate track
7. Edit the track desired.
8. Export it to .wav
9. Import the .wav into the video editor and use that audio in lou of the existing (muted audio) matching it up to the footage

How do you isolate it in a video editor so you can manipulate it?

Audionamix ADX Speech Volume Control plugin will allow separation of dialogue and background elements, but it only accepts mono and stereo inputs.

As Marc mentioned, dialogue is usually in the center channel, which should allow the SVC algorithm an easier workload. Even if the dialogue moves between front channels, with a few passes, SVC should isolate or remove the dialogue completely.

This technique has been used quite successfully in dubbing films to other languages, with only a final mix available.

There is a rental option, in addition to the perpetual license:
https://audionamix.com/technology/adx-svc/

Is this plug-in that works with Audacity? So it work with any 2 channel stereo footage (and thus I would not have to dig up a 6.1 or 5.1 channel video file)?

Is this plug-in that works with Audacity?

VST and AU plugin formats are available, so it should function within Audacity.

I must say that I really dislike Audacity. I know it is a free program that can get the job for many things but I am not partial to the interface.

I have a copy of Premier Pro in the CS4 Suite. I wonder if that would do this? I have been using Resolve (the free version) not sure about the paid versions ability to edit audio in this manor.