Linear PCM audio: 44.1 KHz, monaural, 1-bit-per-second

#11 07-21-2007, 04:04 PM

Radium <glucegen1@gmail.com> writes:

> On Jul 20, 8:42 pm, Jerry Avins <j...@ieee.org> wrote:
>
>> Bits don't come in fractional parts.
>
> I already said the bit-resolution is not fractional.

"Linear PCM" consists of samples of N bits (N integer) at a rate of Fs
samples/second. The bitrate of a linear PCM signal is therefore N*Fs
bits/second.

Since N is 1 at a minimum, then the minimum linear PCM signal bitrate
for Fs = 44100 is 44100 bits/second.
--
% Randy Yates % "I met someone who looks alot like you,
%% Fuquay-Varina, NC % she does the things you do,
%%% 919-577-9882 % but she is an IBM."
%%%% <yates@ieee.org> % 'Yours Truly, 2095', *Time*, ELO
http://home.earthlink.net/~yatescr

#12 07-21-2007, 05:14 PM

Radium wrote:
> Since human hearing goes up 20 KHz. I would think, the minimum
> required to cover the full human hearing range is 20 kbps. Do I guess
> right?

- Read about sample value quantisation,
- read about qunatisation noise,
- read about the Nyquist therorem
and you will end up at about 2*800kbps to reproduce the complete dynamic
and frequency range of the human ear using linear quantisation. However,
usually you do not need all that information. First of all because the
acouesthesia doues not use a similar representation. And so you spaned
range of values that has many many values so close that they are
indistinguishable. On the other side there are a few adjacent values
where you need the resolution. The representation is simply improper for
that use case. But since it is easy from the technical point of view it
is still commonly used.

Marcel

#13 07-21-2007, 07:46 PM

Jerry Avins wrote:
(snip)

> Bits don't come in fractional parts.

a little out of context, but mostly I don't agree.

A decimal digit is worth about 3.32 bits. In any
digital system where the number of possible levels
isn't a power of two you have fractional bits.

-- glen

#14 07-21-2007, 07:52 PM

glen herrmannsfeldt <gah@ugcs.caltech.edu> writes:

> Jerry Avins wrote:
> (snip)
>
>> Bits don't come in fractional parts.
>
> a little out of context, but mostly I don't agree.
>
> A decimal digit is worth about 3.32 bits. In any
> digital system where the number of possible levels
> isn't a power of two you have fractional bits.

No system, binary or not, can have less than two possible levels.
-
% Randy Yates % "Maybe one day I'll feel her cold embrace,
%% Fuquay-Varina, NC % and kiss her interface,
%%% 919-577-9882 % til then, I'll leave her alone."
%%%% <yates@ieee.org> % 'Yours Truly, 2095', *Time*, ELO
http://home.earthlink.net/~yatescr

#15 07-21-2007, 09:15 PM

On Jul 21, 4:52 pm, Randy Yates <ya...@ieee.org> wrote:
> glen herrmannsfeldt <g...@ugcs.caltech.edu> writes:
> > Jerry Avins wrote:
> > (snip)
>
> >> Bits don't come in fractional parts.
>
> > a little out of context, but mostly I don't agree.
>
> > A decimal digit is worth about 3.32 bits. In any
> > digital system where the number of possible levels
> > isn't a power of two you have fractional bits.
>
> No system, binary or not, can have less than two possible levels.

No, but it can have more, and not a power of 2
number of levels. If you don't use fractional
bits per baud somewhere in the middle of your
equations, then your representation may end up
with a different number of bits than the information
capacity of your multilevel channel, thus leading
to an inefficiency.

IMHO. YMMV.
--
rhn A.T nicholson d.0.t C-o-M

#16 07-21-2007, 09:19 PM

"Ron N." <rhnlogic@yahoo.com> writes:

> On Jul 21, 4:52 pm, Randy Yates <ya...@ieee.org> wrote:
>> glen herrmannsfeldt <g...@ugcs.caltech.edu> writes:
>> > Jerry Avins wrote:
>> > (snip)
>>
>> >> Bits don't come in fractional parts.
>>
>> > a little out of context, but mostly I don't agree.
>>
>> > A decimal digit is worth about 3.32 bits. In any
>> > digital system where the number of possible levels
>> > isn't a power of two you have fractional bits.
>>
>> No system, binary or not, can have less than two possible levels.
>
> No, but it can have more, and not a power of 2
> number of levels. If you don't use fractional
> bits per baud somewhere in the middle of your
> equations, then your representation may end up
> with a different number of bits than the information
> capacity of your multilevel channel, thus leading
> to an inefficiency.

I'm looking for some significant information here
and not finding it....

--
% Randy Yates % "Rollin' and riding and slippin' and
%% Fuquay-Varina, NC % sliding, it's magic."
%%% 919-577-9882 %
%%%% <yates@ieee.org> % 'Living' Thing', *A New World Record*, ELO
http://home.earthlink.net/~yatescr

#17 07-22-2007, 12:15 AM

Radium wrote:
> On Jul 20, 8:42 pm, Jerry Avins <j...@ieee.org> wrote:
>
>> Bits don't come in fractional parts.
>
> I already said the bit-resolution is not fractional.

If 44,100 samples are represented by 1 bit, than each sample represents
1/44,100th of a bit. I see that as fractional.

The nice thing about Alzheimer's disease is that one can have the same
discussion over and over and over and .... and it seems fresh each time.
Is that your problem?

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

#18 07-22-2007, 12:19 AM

glen herrmannsfeldt wrote:
> Jerry Avins wrote:
> (snip)
>
>> Bits don't come in fractional parts.
>
> a little out of context, but mostly I don't agree.
>
> A decimal digit is worth about 3.32 bits. In any
> digital system where the number of possible levels
> isn't a power of two you have fractional bits.

A decimal digit may be *worth* about 3.32 binary bits, but because bits
don't come in fractional parts, *representing* a decimal digit requires
rounding up to 4.

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

#19 07-22-2007, 01:06 AM

On Jul 21, 9:15 pm, Jerry Avins <j...@ieee.org> wrote:

> Radium wrote:

> > On Jul 20, 8:42 pm, Jerry Avins <j...@ieee.org> wrote:

> >> Bits don't come in fractional parts.

> > I already said the bit-resolution is not fractional.

> If 44,100 samples are represented by 1 bit, than each sample represents
> 1/44,100th of a bit. I see that as fractional.

No. 1 bit only results after 44,100 cycles are completed. It's like an
extremely-low-geared processing unit. It takes 44,100 cycles to gain 1
bit.

#20 07-22-2007, 01:42 AM

Radium wrote:
> On Jul 21, 9:15 pm, Jerry Avins <j...@ieee.org> wrote:
>
>> Radium wrote:
>
>>> On Jul 20, 8:42 pm, Jerry Avins <j...@ieee.org> wrote:
>
>>>> Bits don't come in fractional parts.
>
>>> I already said the bit-resolution is not fractional.
>
>> If 44,100 samples are represented by 1 bit, than each sample represents
>> 1/44,100th of a bit. I see that as fractional.
>
> No. 1 bit only results after 44,100 cycles are completed. It's like an
> extremely-low-geared processing unit. It takes 44,100 cycles to gain 1
> bit.

Assume you are a salesman. You sell 44,100 items per second, and after
one second you have earned one cent. How much did each customer pay you?
What coin did each customer use?

You don't know what a bit is.
You don't know what a sample is.
You don't know how to use samples to make a waveform.
You are unwilling to believe that there may be something you don't know.
Go away.

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

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