🚀 go-pugleaf

In article <1993Jan9.192008.1528@mtu.edu> cmwolf@mtu.edu (christopher m. wolf) writes:
>kludge@grissom.larc.nasa.gov (Scott Dorsey) writes:
>>In article <1993Jan8.055618.24902@mtu.edu> cmwolf@mtu.edu (christopher m. wolf) writes:
>>>If HDTV will be digital, what will be the number of available colors for
>>>display?
>>
>>Depends on the format that is decided on.
>>
>>>Instead of the "infinite" we have with NTSC now, this will have to be reduced,
>>>depending on the digitalization, but what are we talking about numbers-wise?
>>
>>Infinite colors?  With NTSC?  You have to be joking... the linearity of the
>>chrominance signal is terrible on any NTSC systems.  The number of discrete,
>>distinguisable colors is far fewer than those that can be seen by the eye,
>>or even recorded on a good film.
>>--scott
>
>I looked at it as an analog signal have an infinite number of divisions, every
>one just slightly different.  I wasn't commenting about how it IS being
>used, but rather how it COULD.

Well, first of all an analogue signal doesn't really have an infinite number
of divisions if it's represented as a voltage or a current, because they are
both quantized.  You can't get any unit of charge less than an electron.  It's
just that the number of divisions is extremely large.

In addition, the linearity of the encoding comes into play here.  With the 
NTSC encoding scheme, not very many colors are possible.  But, the number of
colors is going to be a function of the dynamic range of the system and is
therefore dependant on the bandwidth you want to allocate.

In a digital system, it's the same way.  If you allocate more bandwidth, you
can get more of a color range, or you can get more resolution.  The nifty
thing about digital systems is that it permits much easier allocation of
bandwidth (even on the fly!), and although digital encoding generally uses
more bandwidth than the theoretical minimum of an analogue system, because
the baseband signal can be better packed into the available space, it can
be more efficient.
--scott

Disclaimer: NTSC is one of the least efficient color encoding schemes around.
Plus the number of colors is limited, the grey scale isn't very long, and
the resolution is poor.  As far as I can tell, the programming quality isn't
so hot either.

allocate.