When you convert and create a 320kbps mp3 file, you may execute
ffmpeg -i original.wav -b:a 320K out.mp3
But why can
-b:a designate the bit rate? I've read
man ffmpeg and the official ffmpeg Documentation, but
-b:a and even
-b aren't described at all, though some examples can be seen in them. Also, it seems the default bit rate for mp3 is 128kbps, but this is neither referred to.
Does anyone have the verification for the validness of
-b:a option? What do
a mean? BIT-RATE and AUDIO?