[ale] OT: transmitting cable tv wirelessly

aaron aaron at pd.org
Mon Dec 16 22:30:47 EST 2002


On Monday 16 December 2002 13:50, Jeff Hubbs wrote:
> On Mon, 2002-12-16 at 13:43, John Wells wrote:
> > Keith,
> >
> > Thanks for the information.  From what I gather from your message, I
> > would get good quality from the x10 unit but not as good as s-video. 
> > Is there a significant tangible difference in picture quality?
> >
> > It also surprised me that you rank s-video higher than composite, as
> > I had heard the opposite quite a few times.  However, doing a little
> > more research proved you right as far as I can tell.
> >
> > Is NTSC the same composite video as those $30+ monster composite
> > video cables?  Why is composite video so much more expensive than
> > s-video as far as cables go, out of curiosity?
> >
> > Thanks very much for your input.
>
> NTSC (jokingly, "Never Twice the Same Color") *is* "composite video" as
> it's practiced here in the States.  The reason why the Monster
> composite cables are so much more expensive is because they are a
> massively overspecced ripoff.

Actually, those cables area a MONSTROUSLY overpriced ripoff.  ;-)

But to clarify further on the terminology:

-- SVideo is a signal transmission specification where the Luminance and 
Chroma portions of the Video are carried on Separate wires (the "S" part 
of  SVideo). Composite transmission combines the Chroma and Luminance 
into a single signal by Modulating the color information (with a 3.58 mhz 
reference for NTSC). This modulation process causes some harmonic and 
frequency response artifacts in the decoded color image. SVideo avoids 
these subtle encoding artifacts, but one wire Composite signals are the 
cheapest and easiest to distribute, so they remain the most common form 
of video interconnect and transmission. RF signals just employ another 
level of frequency modulation that allows multiple channels of video 
signal to be distributed by broadcast or coaxial cable; RF gets 
de-modulated to video by the TV or the Cable Box.

The really big, highly visible gains for Seperating the Chroma and 
Luminance portions of the signal (in Component or SVideo) are found in 
the recording process, where allocation of the recording media's 
bandwidth can be weighted toward our greater sensitivity for Luminance 
detail. This advantage holds for both analog and digital recording (eg. 
the common 4-1-1 digital Component standard used in DVD's / MPEG 2 
allocates 4 bytes to luminance, but only 1 byte to each of the R-Y & B-Y 
color components. )

-- NTSC (for National Television Standards Committee) is a set of 
specifications which define open, public standards for television signals 
including voltages, frequencies, frame rates, scan rates, frequency 
response and encoding techniques for both broadcast and direct 
transmission. (PAL is a very similar set of specifications and standards 
that is used for most of Europe. There is a third relevant standard, 
SECAM, but that is a truly crippled and rapidly fading French technology 
that is mostly used in their former territories and in the countries that 
comprised the former Soviet Union; SECAM is kind of like the windows OS 
of television standards.) Most every signal meant to connect to a 
Television device will follow one of those three standards, regardless of 
the Component, SVideo, Composite or RF delivery in an encoded, compressed 
or uncompressed digital or analog format.

Hope that clarified without being too horribly AR. :^)

peace
 Aaron 
 Ruscetta

_______________________________________________
Ale mailing list
Ale at ale.org
http://www.ale.org/mailman/listinfo/ale






More information about the Ale mailing list