What's the meaning of "sample rate" in MP3/Vorbis/AAC?, Considering the audio was transformed Options

[sheh]

What's the meaning of "sample rate" in MP3/Vorbis/AAC? Wouldn't it be meaningless after transform, same as bit depth?

[Dynamic]

I think one problem is that we're never doing a Fourier Transform of the entire file.

Instead we do overlapping windowed transforms, which don't preserve all the frequency content of the original file accurately (and spread the single frequencies across multiple bins.

Given that there must be frequency spreading, there will at least be some difficulty in anti-aliasing, and there will also be elements of temporal spreading too.

I admit that I haven't got my head around the whole concept, though it has occurred to me in thinking about things like pitch-shifting or tempo-shifting but I still haven't worked out all the pitfalls.

I know that algorithms like Soundtouch have audible problems especially on multi-instrument/vocalist samples.

This post has been edited by Dynamic: Oct 8 2012, 23:07