How to rip audio from an MP4 file and add it to an AVI clip?

[saadi]

Hi guys, hopefully am posting this question in the right forum

I need some help. I've downloaded 2 versions of a movie in different formats and I want to keep just one of them. The first one is an MP4 file while the other one has an AVI extension. The mp4 despite being smaller in size has a much better audio while the AVI has better picture.

Is it possible for me to extract the AAC audio from the MP4 file and add it to the AVI clip?

Here are the file properties for both:

MP4: (700MB) Media length: 02:00:34 size: 720 x 336

Video: MPEG4 Video (H264) 720x336 23.98fps [Video]
Audio: AAC 48000Hz stereo 1536Kbps [Audio]

AVI: (1400MB) Media length: 02:00:34 size: 704 x 304

Video: XVID 704x304 23.98fps 1425Kbps [Video 0]
Audio: Dolby AC3 48000Hz stereo 192Kbps [Audio 1]

..I have absolutely no knowledge about this stuff so any help would be greatly appreciated!

[t0nee1]

I’ll be glad to offer some help, providing the Mods say it’s ok…Since you stated this,

I’ve downloaded 2 versions of a movie in different formats and I want to keep just one of them

[Kerry56]

There has been no mention of specific movies, and not all downloaded material is illegal t0nee1. In such a case, we give the poster the benefit of a doubt.

[Sean]

The Bitrate you mentioned for your MP4’s AAC sound track does not appear to be correct.

1536kbps = 192KB per second -> 11.25MB per minute -> 1350MB for 120 minutes (movie length you reported).

If you were going by the bitrate, I would suggest comparing a few small sections to see if you can hear the different in sound between the two before trying to swap the soundtracks and resync the audio with the video. Not many people can hear the difference between CD and a Dolby Digital stereo sound track created from the CD at 192kbps. For a movie, this is less important, where people focus more at the action than at the sound, unless this is live music.

[t0nee1]

[QUOTE=Kerry56;2238018]There has been no mention of specific movies, and not all downloaded material is illegal t0nee1. In such a case, we give the poster the benefit of a doubt.[/QUOTE]

Point taken!..

@ OP,

Even if the bitrate[I] was[/I] correct, I’m not sure AAC audio is [I]fully[/I] supported in an AVI container…Of course, I could be wrong…Have been wrong in the past, and it won’t be the last…
Having said that, you could try extracting the video and AAC audio from .MP4 with Yamb, and mux a new avi with Avi Mux Gui…
Might try with Xvid4PSP, or Avidemux…

[saadi]

guys thanks a lot for the help, the bit rate for the AAC file is indeed 1536kbps (or so the properties in media player classic read!) and the audio is clearly better than the other one… i’ll try and play around with some of the softwares t0nee1 mentioned and see what i can manage