问题
It is said, that MP3 frame contains 1152 samples. What is a "sample" then? A pair of values for right AND left channel? Or an individual value fro right OR left channel?
回答1:
The language that is used can get a little bit confusing. The just of it is that each frame will have 1152 (or 384, or 576 depending on MPEG version and layer) per audio channel. How that data actually gets stored is more complicated than a single value for each channel because of compression.
If you want to learn more I would recommend http://blog.bjrn.se/2008/10/lets-build-mp3-decoder.html for a nice, detailed blog that builds up the reader's understanding of the MP3 format for the sake of building a decoder.
You can also see http://wiki.hydrogenaudio.org/index.php?title=MP3#Polyphase_Filterbank_Formula for rather technical information. Link is anchored to a section that says specifically: "Audio is processed by frames of 1152 samples per audio channel" But the whole page describes aspects of the MP3 format.
来源：https://stackoverflow.com/questions/11253233/what-is-a-sample-in-mp3