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

Started by Radium July 20, 2007
Hi:

Is the following possible?:

A linear uncompressed PCM audio file whose sample-rate is 44.1 KHz,
monaural, and with a bit-rate of 1-bit-per-second.

The 1-bit-per-second is because the bit-resolution [normally 16-bit in
CD audio] is only 1-bit-per-44,100 samples in this hypothetical case.
Since the sample-rate is 44.1 KHz, and there is only 1 channel [due to
the monaural audio], the bit-rate is 1-bit-per-second.

Bit rate = sample rate X bit-resolution X # of channels

44,100 Hz X 1/44,100-bit X 1 channel = 1

Please note that the 1/44,100-bit is not a fractional bit-resolution
but rather it represents the fact that there is only 1 bit for every
44,100 samples.

Is the above scenario possible? Did I explain it correctly? If so,
what would such audio sound like? Bad-quality?


Thanks,

Radium

On Jul 21, 1:52 am, Radium <gluceg...@gmail.com> wrote:
> Hi: > > Is the following possible?: > > A linear uncompressed PCM audio file whose sample-rate is 44.1 KHz, > monaural, and with a bit-rate of 1-bit-per-second. > > The 1-bit-per-second is because the bit-resolution [normally 16-bit in > CD audio] is only 1-bit-per-44,100 samples in this hypothetical case. > Since the sample-rate is 44.1 KHz, and there is only 1 channel [due to > the monaural audio], the bit-rate is 1-bit-per-second. > > Bit rate = sample rate X bit-resolution X # of channels > > 44,100 Hz X 1/44,100-bit X 1 channel = 1 > > Please note that the 1/44,100-bit is not a fractional bit-resolution > but rather it represents the fact that there is only 1 bit for every > 44,100 samples.
This makes no sense. How can you describe 44100 samples with a single bit? -- Oli
Oli Charlesworth wrote:
> On Jul 21, 1:52 am, Radium <gluceg...@gmail.com> wrote: >> Hi: >> >> Is the following possible?: >> >> A linear uncompressed PCM audio file whose sample-rate is 44.1 KHz, >> monaural, and with a bit-rate of 1-bit-per-second. >> >> The 1-bit-per-second is because the bit-resolution [normally 16-bit in >> CD audio] is only 1-bit-per-44,100 samples in this hypothetical case. >> Since the sample-rate is 44.1 KHz, and there is only 1 channel [due to >> the monaural audio], the bit-rate is 1-bit-per-second. >> >> Bit rate = sample rate X bit-resolution X # of channels >> >> 44,100 Hz X 1/44,100-bit X 1 channel = 1 >> >> Please note that the 1/44,100-bit is not a fractional bit-resolution >> but rather it represents the fact that there is only 1 bit for every >> 44,100 samples. > > This makes no sense. How can you describe 44100 samples with a single > bit?
Come on Oli. Surely you've heard of lossy compression. :-) Steve
Radium <glucegen1@gmail.com> writes:

> Hi: > > Is the following possible?: > > A linear uncompressed PCM audio file whose sample-rate is 44.1 KHz, > monaural, and with a bit-rate of 1-bit-per-second.
No. -- % Randy Yates % "Midnight, on the water... %% Fuquay-Varina, NC % I saw... the ocean's daughter." %%% 919-577-9882 % 'Can't Get It Out Of My Head' %%%% <yates@ieee.org> % *El Dorado*, Electric Light Orchestra http://home.earthlink.net/~yatescr
Oli Charlesworth wrote:
> On Jul 21, 1:52 am, Radium <gluceg...@gmail.com> wrote: >> Hi: >> >> Is the following possible?: >> >> A linear uncompressed PCM audio file whose sample-rate is 44.1 KHz, >> monaural, and with a bit-rate of 1-bit-per-second. >> >> The 1-bit-per-second is because the bit-resolution [normally 16-bit in >> CD audio] is only 1-bit-per-44,100 samples in this hypothetical case. >> Since the sample-rate is 44.1 KHz, and there is only 1 channel [due to >> the monaural audio], the bit-rate is 1-bit-per-second. >> >> Bit rate = sample rate X bit-resolution X # of channels >> >> 44,100 Hz X 1/44,100-bit X 1 channel = 1 >> >> Please note that the 1/44,100-bit is not a fractional bit-resolution >> but rather it represents the fact that there is only 1 bit for every >> 44,100 samples. > > This makes no sense. How can you describe 44100 samples with a single > bit?
Bits don't come in fractional parts. We've been all over this in the past with Radium here. He's an enigma; I can't really tell if he is a troll, or a lunatic. Either way, he's best ignored. Jerry -- Engineering is the art of making what you want from things you can get. &macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;
On Jul 20, 8:42 pm, Jerry Avins <j...@ieee.org> wrote:
> Oli Charlesworth wrote: > > On Jul 21, 1:52 am, Radium <gluceg...@gmail.com> wrote: > >> Hi: > > >> Is the following possible?: > > >> A linear uncompressed PCM audio file whose sample-rate is 44.1 KHz, > >> monaural, and with a bit-rate of 1-bit-per-second. > > >> The 1-bit-per-second is because the bit-resolution [normally 16-bit in > >> CD audio] is only 1-bit-per-44,100 samples in this hypothetical case. > >> Since the sample-rate is 44.1 KHz, and there is only 1 channel [due to > >> the monaural audio], the bit-rate is 1-bit-per-second. > > >> Bit rate = sample rate X bit-resolution X # of channels > > >> 44,100 Hz X 1/44,100-bit X 1 channel = 1 > > >> Please note that the 1/44,100-bit is not a fractional bit-resolution > >> but rather it represents the fact that there is only 1 bit for every > >> 44,100 samples. > > > This makes no sense. How can you describe 44100 samples with a single > > bit? > > Bits don't come in fractional parts. We've been all over this in the > past with Radium here. He's an enigma; I can't really tell if he is a > troll, or a lunatic. Either way, he's best ignored.
I've wondered whether another similar poster was an AI system gone awry, or maybe even something using our responses as data as part of Turing-Test AI experiment. If the sound being recorded at 44.1 kHz has only 2 possible waveform templates per second (say synchronous Morse code at exactly 1 wpm), then the information content might approach 1 bps (or less), after a sync or description header perhaps. IMHO. YMMV. -- rhn A.T nicholson d.0.t C-o-M
On Fri, 20 Jul 2007 17:52:54 -0700, Radium <glucegen1@gmail.com>
wrote:

>Hi: > >Is the following possible?: > >A linear uncompressed PCM audio file whose sample-rate is 44.1 KHz, >monaural, and with a bit-rate of 1-bit-per-second.
Audio at 1bps is not possible if you want it conveyed in real time. It is absolutely possible to convey 1bps with a 44.1kHz sample rate, but that's the sort of thing you'd do for something like deep-space communications where the channel makes it nearly impossible to recover the data, not something you'd use for PCM file storage.
>The 1-bit-per-second is because the bit-resolution [normally 16-bit in >CD audio] is only 1-bit-per-44,100 samples in this hypothetical case. >Since the sample-rate is 44.1 KHz, and there is only 1 channel [due to >the monaural audio], the bit-rate is 1-bit-per-second.
CD audio is 16 bits per sample, so there are 16x44100 = 705600 bits per second. If you want to compress audio by a factor of 705600 yo get 1bps instead of 705600bps there's not going to be anything left to hear.
>Bit rate = sample rate X bit-resolution X # of channels > >44,100 Hz X 1/44,100-bit X 1 channel = 1 > >Please note that the 1/44,100-bit is not a fractional bit-resolution >but rather it represents the fact that there is only 1 bit for every >44,100 samples. > >Is the above scenario possible? Did I explain it correctly? If so, >what would such audio sound like? Bad-quality?
There'd be no audio because human hearing only goes down to about 10-20Hz. So you need, even with only 1 bit per sample, a minimum of 20-40bps, and that's with a completely saturated signal that will sound like crap and only be able to support the lowest possible audible frequency...i.e., pretty much not contain anything useful. Eric Jacobsen Minister of Algorithms Abineau Communications http://www.ericjacobsen.org

Steve Underwood wrote:
> Oli Charlesworth wrote: > >> On Jul 21, 1:52 am, Radium <gluceg...@gmail.com> wrote: >>
>>> A linear uncompressed PCM audio file whose sample-rate is 44.1 KHz, >>> monaural, and with a bit-rate of 1-bit-per-second. >>> >> >> This makes no sense. How can you describe 44100 samples with a single >> bit?
That's simple. It is probably enough of 32 bits to index all of the content that was ever issued on CD.
> Come on Oli. Surely you've heard of lossy compression. :-)
You mean lousy compression? :-)
> Steve
Vladimir Vassilevsky DSP and Mixed Signal Design Consultant http://www.abvolt.com
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.
On Jul 21, 10:35 am, Eric Jacobsen <eric.jacob...@ieee.org> wrote:

> On Fri, 20 Jul 2007 17:52:54 -0700, Radium <gluceg...@gmail.com> > wrote:
> >Is the above scenario possible? Did I explain it correctly? If so, > >what would such audio sound like? Bad-quality?
> There'd be no audio because human hearing only goes down to about > 10-20Hz. So you need, even with only 1 bit per sample, a minimum of > 20-40bps, and that's with a completely saturated signal that will > sound like crap and only be able to support the lowest possible > audible frequency...i.e., pretty much not contain anything useful.
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?