Stripping audio off music video and using FLAC as audio instead?

[SE14man]

Hi there

I got some DVDs of music videos. I wondered if this is even possible.

Want to rid the audio track and instead put a better quality audio track to match the music video.

I have a load of old music videos which are mp4 but want to make the audio as FLAC. I do have the lossless FLAC files. Can I do this without having to re encode the video which would give quality loss (I think?)

Cheers!

[DB83]

For clarity, are you saying that the dvds contain the mp4's as data rather than standard dvds ir mpeg2 video etc. ?

It is relatively easy to demux mp4's into separate video and audio tracks - I believe that MyMp4boxGui can do this with a few clicks.

You can use the same program to mux back to mp4. I do not know if it reencodes but I suspect it does not. Ffmpeg could also do this.

More complicated though would be to match existing video with a separate audio track unless both were exact - the audio on the video came from the same source and started at the same point . You would probably need an NLE to do that. More so, I do not thing mp4 supports FLAC. But it would support PCM (from an original CD)

[SE14man]

Thanks very much for your reply.

What it is is that I got quite a number of song videos/music videos from maybe 12 years ago. The audio bitrate I think is around 128 kbps. However i have the exact same songs on mp3 and the mp3s are 320. So I wondered if it would be possible to match that 320 mp3 up to the music video? Just to make the audio better quality? Then preferably not have to re encode the video as i heard re encoding video loses quality.

I hope i have made sense

Thanks again

Just to also add the mp3 of the songs are exactly the same duration as the vids so hopefully wont have to go stretching etc etc

[hech54]

If the band used their CD/Album release as their model for the music video, then yes it can easily be done without re-encoding the video. I use AviDemux exclusively for this kind of work.

[SE14man]

Thank you very much this looks exactly to be what t I am after.
Do you know if there would be any guides available to assist me with this sort of thing or is it all quite straight forward?

[SE14man]

It's ok I think I have actually found quite a few tutorials on YouTube about it many thanks again

[hech54]

Don't forget to add your suffix to your file name (.mpg, .mp4 etc etc).
As long as you choose COPY for your video, and make no changes, the video is not re-encoded.
You CAN adjust the audio sync while COPYing.....but just delaying or jumping the start time.

[SE14man]

All right excellent thanks for the tips

[SE14man]

Just another question now

What I would actually like to do is make the video join up to a lossless file I have. When I try to save the video merged with my lossless audio file i get an error saying 'Only AAC, AC3. E-AC3 and mpegaudio supported audio'

So how do i add a lossless audio file? The audio was FLAC but i decoded it to WAV in the hope it would let me have that instead but it isn't.

Is there a way around this? Just want the audio on the music video to be lossless.

If this is a long process I can just make do with 320. Bit of an audiophile i guess :P

Cheers.

[DB83]

Wav as uncompressed PCM should be supported by the mp4 container.

Going from FlAC to PCM will involve a reencoding. But you simply can not re-create the data that has been lost from a compressed, even losslessly, format to an uncompressed one.

I suggest you detail your process from FL:AC to WAV to etermone what has actually happened.

I already inferred that the losslessly compressed FLAC would not be supported