About CD Audio encoding...

BigMoosie · 4th April 2005, 23:21

It is my understanding that on a CD every sample of audio is recorded using a 16 bit string of data. Also that this number recorded symolises the amplitude of the wave at that point. There is one thing I do not understand...

There are equal number of positive amplitudes possible as there are negative, and there is also the possibility of zero. That leaves us with an odd number of possible amplitudes yet 2^16 is an even number. What do the left-over bit sequences represent?

ScorLibran · 5th April 2005, 03:58

There's a parity bit.

even number of bits + even number of bits + 0 + one parity bit = an even number of bits (i.e., 2^16)

(This is the simple explanation...there's a lot more to it than that, with control bits, synch bits, etc. More info....)

BigMoosie · 5th April 2005, 07:15

EDIT: hadnt seen the link, will do now

4th April 2005, 23:21	#1
BigMoosie Banned Join Date: Apr 2005 Posts: 105	About CD Audio encoding... It is my understanding that on a CD every sample of audio is recorded using a 16 bit string of data. Also that this number recorded symolises the amplitude of the wave at that point. There is one thing I do not understand... There are equal number of positive amplitudes possible as there are negative, and there is also the possibility of zero. That leaves us with an odd number of possible amplitudes yet 2^16 is an even number. What do the left-over bit sequences represent?

5th April 2005, 03:58	#2
ScorLibran Resident Floydian Join Date: Aug 2003 Posts: 6,222	There's a parity bit. even number of bits + even number of bits + 0 + one parity bit = an even number of bits (i.e., 2^16) (This is the simple explanation...there's a lot more to it than that, with control bits, synch bits, etc. More info....) I'm a psychosomatic sister running around without a leash.

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5th April 2005, 07:15	#3
BigMoosie Banned Join Date: Apr 2005 Posts: 105	EDIT: hadnt seen the link, will do now