Digital audio stream terms?
DaveC wrote:
On Thu, 20 May 2004 20:26:29 -0700, Richard Crowley wrote
(in article ):
"DaveC" wrote in message
al.net...
I'm listening to a stream via WMP. The Get Info box says:
Bit Rate: 24 Kbps
Audio Codec: Windows Media Audio 9
20 kbps, 32kHz, mono 1-pass CBR
Can someone please clarify what the bit rate means and what the
audio codec numbers (20 kbps & 32 KHz) mean?
I believe they mean...
20 kbps = 20,000 (or 20480?) bits per second of data
through the network into your computer for this stream.
My guess would be that the 24 Kbps is the network stream speed...
32kHz = the (original?) sample rate implying absolute
maximum 16KHz high frequency limit (likely lower).
CBR = constant (vs. variable/dynamic) bit-rate.
Anyone else?
Both definitions are correct...
With streaming audio, the kbps figure represents the number of Kilo Bits Per
Second being streamed down into your computer. The kHz figure represents
the sample rate, i.e. the number of samples per second when the source was
sampled.
CBR = Constant bit rate. That is to say the sample/rip was taken at a fixed
kbps value. Some encoders can calculate the 'best' (a-hem) bit rate on the
fly, this is known as VBR (Variable Bit Rate).
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