Converting AC3 to AAC in an MP4


#1

Is there an easy way to do this without messing up the video file? I made the mistake of encoding a bunch of my movies and TV shows with AC3 stereo and I'm wanting to convert that AC3 stereo track to AAC so I don't have to re-encode all the stuff I messed up. I know there is a lot of software out there that claims to do this, but does anyone here have experience with any in particular you'd recommend?


#2

check out "MP4Tools" -- the app should allow you to select how to treat every single stream when transcoding, incl. video pass-through.
http://www.emmgunn.com/mp4tools-home/mp4tools-user-guide/

Other apps like Handbrake will always transcode the video. You can still use it but then you'll need to do this in 2 separate steps (step 1: transcode file w/ AAC audio, step 2: get a muxer to combine the original video with the new audio tracks).


#3

On Windows, with a little bit of learning, you can use
https://www.xmedia-recode.de/en/index.html
which is a frontend for the universal tool ffmpeg


#4

@OttoKerner said:
On Windows, with a little bit of learning, you can use
https://www.xmedia-recode.de/en/index.html
which is a frontend for the universal tool ffmpeg

Not too much learning...
The Germans that designed it made it so easy to use there are no instructions, no forums, no help desk. A 'slow child' could figure it out in minutes (I did - so there you go).

The trick is:
Select Container
Copy Video
Convert Audio

I also 'Normalize' the audio track while that's happening, but that's an 'Advanced' feature (usually mastered somewhere around hour 2).

lol


#5

@tom80H said:
check out "MP4Tools" -- the app should allow you to select how to treat every single stream when transcoding, incl. video pass-through.
http://www.emmgunn.com/mp4tools-home/mp4tools-user-guide/

Other apps like Handbrake will always transcode the video. You can still use it but then you'll need to do this in 2 separate steps (step 1: transcode file w/ AAC audio, step 2: get a muxer to combine the original video with the new audio tracks).

Seems this only works for Mac.

@OttoKerner said:
On Windows, with a little bit of learning, you can use
https://www.xmedia-recode.de/en/index.html
which is a frontend for the universal tool ffmpeg

Can this do it without a re-encode?


#6

@PolygonGTC said:

@tom80H said:
check out "MP4Tools" -- the app should allow you to select how to treat every single stream when transcoding, incl. video pass-through.
http://www.emmgunn.com/mp4tools-home/mp4tools-user-guide/

Other apps like Handbrake will always transcode the video. You can still use it but then you'll need to do this in 2 separate steps (step 1: transcode file w/ AAC audio, step 2: get a muxer to combine the original video with the new audio tracks).

Seems this only works for Mac.

@OttoKerner said:
On Windows, with a little bit of learning, you can use
https://www.xmedia-recode.de/en/index.html
which is a frontend for the universal tool ffmpeg

Can this do it without a re-encode?

It's an 'Audio Recode', of course...:
Copy Video <--- video stream untouched
Convert Audio <---- audio stream converted to AAC - since that's what you want to do.

Process only takes a few minutes.


#7

@JuiceWSA said:

It's an 'Audio Recode', of course...:
Copy Video <--- video stream untouched
Convert Audio <---- audio stream converted to AAC - since that's what you want to do.

Process only takes a few minutes.

Okay, I knew it would have to re-encode the audio. Just wanted to make sure it would passthrough the AC3 5.1 track and video unchanged. I downloaded it and gave it a try and it seems to work flawlessly and it's hardly complicated.

Thanks for the suggestions! It looks like this will work perfect.


#8

Yep, that thing is used more often than FileBot around here.
If you look at my desktop you'll probably find it's open and doing something.

Enjoy


#9

Interesting, I would have thought Handbrake would have got a mention.

https://handbrake.fr/


#10

@SE56 said:
Interesting, I would have thought Handbrake would have got a mention.
https://handbrake.fr/

Handbrake will always convert the video stream, which is unnecessary and undesirable in this use case.


#11

Exactly. I used Handbrake to encode them initially and I don't want to re-encode it. I just want to convert the AC3 stereo track to AAC and Xmedia does exactly that, passing through the video and the AC3 5.1 track untouched.


#12

@OttoKerner said:

@SE56 said:
Interesting, I would have thought Handbrake would have got a mention.
https://handbrake.fr/

Handbrake will always convert the video stream, which is unnecessary and undesirable in this use case.

"The right tool for the job at hand, Laddy..."
"The more they overthink the plumbing, the easier it is to stop up the drain."

Montgomery Christopher Jorgensen "Scotty" Scott

Handy Handbrake Guide in my signature - BTW