Entropy of Music
On 2011-04-22, RichD wrote:
Claude Shannon estimated music at 40 bits/sec entropy. What does
MP3 achieve?
MP3 bitrate is a tunable parameter, though it doesn't go as low as
40 bits/s. In fact MP3 typically has about 40 frames per second, and a
frame header requires a lot more than 1 bit.
However, the format encodes a *lot* more than a musical score. Every
note from an instrument in a performance is different, and people can
hear many of those differences. A performance compressed to 40 bit/s
would be much more regular and "mechanical" than any real performance.
Still, it is true that MP3 is poor at compressing very similar sounds
that are temporally separated. Frames are mostly independent of one
another, so that even most short-range temporal structure is
completely ignored.
--
Tim
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