A good article to understand dithering---
http://en.wikipedia.org/wiki/Dithering
>
>Hello All,
>
> I have a strange but basic query . I am not able to understand
>the role played by dither while encoding the audio i.e. transform
>coefficients which are quite signals because as we see in encoders
>like AC-3 where in if the singal has low amplitudes then it is like
>encoded with dither which is a random noise that is being added to the
>bit stream which is said to increase the quality of the signals .
> I am not able to understand the rold played by this random noise.As
>per my knowledge this randome noise is said to remove the quatisation
>error which makes sense since low amplitude singals are always
>susceptibal to more noise being added to them while quantisation but
>while decoding even if we came to know about this noise and decoded it
>..then also in my opinion it cannot be part of the audio output ?
> Please tell me if i am making a mistake in interpreting the things.
>
>Regards,
>Pankaj
>
>
Re: Dither
Started by ●July 18, 2007
Reply by ●July 19, 20072007-07-19
Dither is used only to represent the feeble sample values. In case of AC-3
if u have the exponent for a sample and the number of bits to be allocated
fro its mantissa turn out to be zero, for bit rate constraints, dither is
used, coz its a feeble sample, and some variation in its value is not
perceptible, also sufficient information of the sample is passed in the
exponent.
On 7/18/07, b...@yahoo.com wrote:
>
> A good article to understand dithering---
> http://en.wikipedia.org/wiki/Dithering
>
> >
> >Hello All,
> >
> > I have a strange but basic query . I am not able to understand
> >the role played by dither while encoding the audio i.e. transform
> >coefficients which are quite signals because as we see in encoders
> >like AC-3 where in if the singal has low amplitudes then it is like
> >encoded with dither which is a random noise that is being added to the
> >bit stream which is said to increase the quality of the signals .
> > I am not able to understand the rold played by this random noise.As
> >per my knowledge this randome noise is said to remove the quatisation
> >error which makes sense since low amplitude singals are always
> >susceptibal to more noise being added to them while quantisation but
> >while decoding even if we came to know about this noise and decoded it
> >..then also in my opinion it cannot be part of the audio output ?
> > Please tell me if i am making a mistake in interpreting the things.
> >
> >Regards,
> >Pankaj
> >
> >
--
Be the change u want to see in the world -- M K Gandhi
if u have the exponent for a sample and the number of bits to be allocated
fro its mantissa turn out to be zero, for bit rate constraints, dither is
used, coz its a feeble sample, and some variation in its value is not
perceptible, also sufficient information of the sample is passed in the
exponent.
On 7/18/07, b...@yahoo.com wrote:
>
> A good article to understand dithering---
> http://en.wikipedia.org/wiki/Dithering
>
> >
> >Hello All,
> >
> > I have a strange but basic query . I am not able to understand
> >the role played by dither while encoding the audio i.e. transform
> >coefficients which are quite signals because as we see in encoders
> >like AC-3 where in if the singal has low amplitudes then it is like
> >encoded with dither which is a random noise that is being added to the
> >bit stream which is said to increase the quality of the signals .
> > I am not able to understand the rold played by this random noise.As
> >per my knowledge this randome noise is said to remove the quatisation
> >error which makes sense since low amplitude singals are always
> >susceptibal to more noise being added to them while quantisation but
> >while decoding even if we came to know about this noise and decoded it
> >..then also in my opinion it cannot be part of the audio output ?
> > Please tell me if i am making a mistake in interpreting the things.
> >
> >Regards,
> >Pankaj
> >
> >
--
Be the change u want to see in the world -- M K Gandhi
