When a computer transcodes an audio file from one file format to another, does the computer first decode it into the raw digital stream (exactly what is fed into the DAC for the audio output) , or does it do something different without having to completely decode it?
Take Spotify files for example, I believe that they are not in a standard MP3 format that can be played on any device. However, shouldn't it be relatively easy to convert these files into standard MP3 files, by first decoding them and then re-encoding to MP3 format?
Or would it require getting the analogue audio, converting it back to digital and then encoding again. My main query is, do we generally have access to this raw decoded digital audio data?