This is akin to an idea I had in college that if we take any multimedia or any data that is in the format of header+fixed size of data, we can fourier transform

This is akin to an idea I had in college that if we take any multimedia or any data that is in the format of header+fixed size of data, we can fourier transform it and the frequency at which headers occur will spike as they repeat with the same frequency, thus we can easily identify data that looks like multimedia and even have an idea about the contents! Man did the stupidity of that idea shine through when I actually read up on how things /really/ worked.