Difference Between RGB and component

[Tom]

hello
can someone give me a good explanation of the differences between RGB
and component inputs. What is the preferred method and what is the
best quality in terms of image. My TV has a scart connection with RGB
but mentions nothing about component. I thought component was supposed
to produce the best image but others tell me its RGB.

thnks
tom

[mddawson]

The article here may hep: http://www.michaeldvd.com.au/Articles/VideoConnectors/VideoConnectors.asp

[Mike]

Tom wrote:
> hello
> can someone give me a good explanation of the differences between RGB
> and component inputs. What is the preferred method and what is the

http://www.google.com.au/search?q=component+vs+rgb

Funnily, you are not the first to ask.

> I thought component was supposed
> to produce the best image but others tell me its RGB.

They have equivalent info. 1:1 mapping .

[vortex]

Not a bad guide, but not compleatly correct in some patches.


Component really just indicates that the colour signal is seperated into it
indervidual "components". There are two common ways of doing this, RGB or
YUV (also called YPbPr or YCbCr). DVDs nativly use YUV, where as TVs use
RGB.

As of such there is no difference between "RGB" and "component" as RGB is
component. The difference is between YUV component ad RGB component.

You can buy an adapter from jaycar to convert YUV to RGB, and I have also
seen RGB to YUV convertors in other stores. They cost between $100 to $200.


"mddawson" <mddawson.18c1ia@no-mx.forums.eyo.com.au> wrote in message
news:mddawson.18c1ia@no-mx.forums.eyo.com.au...
>
> The article here may hep: http://tinyurl.com/uf1
>
>
> --
> mddawson
> ------------------------------------------------------------------------
> mddawson's Profile: http://forums.eyo.com.au/member.php?userid=8112
> View this thread: http://forums.eyo.com.au/showthread.php?t=52973
>

[Michael Garibaldi]

vortex wrote:
> Not a bad guide, but not compleatly correct in some patches.
>
>
> Component really just indicates that the colour signal is seperated into it
> indervidual "components". There are two common ways of doing this, RGB or
> YUV (also called YPbPr or YCbCr). DVDs nativly use YUV, where as TVs use
> RGB.
>
> As of such there is no difference between "RGB" and "component" as RGB is
> component. The difference is between YUV component ad RGB component.
Ahh No... RGB is 3 color signals and component is 2 color difference
with 1 luminance. RGB usually doen't have sync information either, where
as component does. RGB can come with sync information on the green
channel too. So as mentioned in the Link RGB is Red Green Blue and
Component is (Y)Luminance, (U)Blue - Luminance & (V)Red - Luminance
which is more correctly known as CAV (C)omponent (A)nalog (V)ideo.
>
> You can buy an adapter from jaycar to convert YUV to RGB, and I have also
> seen RGB to YUV convertors in other stores. They cost between $100 to $200.
>
>
> "mddawson" <mddawson.18c1ia@no-mx.forums.eyo.com.au> wrote in message
> news:mddawson.18c1ia@no-mx.forums.eyo.com.au...
>
>>The article here may hep: http://tinyurl.com/uf1
>>
>>
>>--
>>mddawson
>>------------------------------------------------------------------------
>>mddawson's Profile: http://forums.eyo.com.au/member.php?userid=8112
>>View this thread: http://forums.eyo.com.au/showthread.php?t=52973
>>
>
>
>

[Michael Garibaldi]

vortex wrote:

> Not a bad guide, but not compleatly correct in some patches.
>
>
> Component really just indicates that the colour signal is seperated into it
> indervidual "components". There are two common ways of doing this, RGB or
> YUV (also called YPbPr or YCbCr). DVDs nativly use YUV, where as TVs use
> RGB.
>
> As of such there is no difference between "RGB" and "component" as RGB is
> component. The difference is between YUV component ad RGB component.
>
> You can buy an adapter from jaycar to convert YUV to RGB, and I have also
> seen RGB to YUV convertors in other stores. They cost between $100 to $200.
>
BTW If your SCART only has RGB without syncs incoded on Green your make
a simple device that will provide RGB+HV for under AUD$30.
>
> "mddawson" <mddawson.18c1ia@no-mx.forums.eyo.com.au> wrote in message
> news:mddawson.18c1ia@no-mx.forums.eyo.com.au...
>
>>The article here may hep: http://tinyurl.com/uf1
>>
>>
>>--
>>mddawson
>>------------------------------------------------------------------------
>>mddawson's Profile: http://forums.eyo.com.au/member.php?userid=8112
>>View this thread: http://forums.eyo.com.au/showthread.php?t=52973
>>
>
>
>

[Stephen Neal]

"Tom" <gekko71@yahoo.com> wrote in message
news:bf3974de.0406231741.b0e61cd@posting.google.co m...
> hello
> can someone give me a good explanation of the differences between RGB
> and component inputs. What is the preferred method and what is the
> best quality in terms of image. My TV has a scart connection with RGB
> but mentions nothing about component. I thought component was supposed
> to produce the best image but others tell me its RGB.

RGB and Component inputs should offer very similar picture quality in a
domestic environment everything else being equal. It is possible to move
from RGB to YPrPb component pretty much losslessly.

Modern digitial TV production and recording (from broadcast VTRs to digital
TV and DVD) all use component digital sampling of Y (luminance) and Cr/Cb
(colour difference signals) and usually the CrCb colour difference signals
(Cr is a weighted version of R-Y, Cb is a weighted version of B-Y) are sent
at a lower horizontal (and often also vertical) resolution. This is better
done in the YCrCb domain than the RGB domain. YCrCb is what is transmitted
via digital TV or recorded on DVD. However conversion from YCrCb to RGB
should be nearly lossless (only a bit of noise and possible rounding
assuming the signal is "legal") - and most TVs have to convert from YPrPb to
RGB for display anyway, so you are just moving the conversion process by
using differnet types of interconnect. (RGB and Component are both clean
component systems - they aren't going to differ from each other like
S-video/composite will with RGB or Component - where S-video and RGB mangle
the picture using sub-carrier chroma techniques which adds all sorts of
nastiness)

However in the realm of TV interconnect there is one major difference -
YPrPb component connections are also used to carry a progressive standard
definition or an HDTV interlaced or progressive signal to and from suitable
kit. This is far less common for RGB SCART connections (and not really part
of the SCART standard?) - more for the fact that HD and progressive have yet
to make in-roads in Europe - so the US/Japanese component interconnection
has become the de-facto HD/Progressive connection standard.

So RGB SCART and Component should be pretty much identical in quality terms
for a standard definition, non-progressive, connection - i.e. a normal
set-top box or DVD to TV connection - and RGB should give excellent results.

It is only when you get to progressive/HD that component connections are
required rather than SCART. Probably not an issue for you.

Also - in terminology terms - as I understand it - PrPb normally refers to
analogue colour difference signals, CrCb their digital counterparts. U and
V are often also used - though these really refer to a specific weighting of
colour differences in PAL composite encoder/decoders - I&Q are rotated
versions used in NTSC stuff?

Steve

[Tom]

"Stephen Neal" <stephen.neal@nospam.as-directed.com> wrote in message news:<cbed2a$1n5$1$830fa795@news.demon.co.uk>...
> "Tom" <gekko71@yahoo.com> wrote in message
> news:bf3974de.0406231741.b0e61cd@posting.google.co m...
> > hello
> > can someone give me a good explanation of the differences between RGB
> > and component inputs. What is the preferred method and what is the
> > best quality in terms of image. My TV has a scart connection with RGB
> > but mentions nothing about component. I thought component was supposed
> > to produce the best image but others tell me its RGB.
>
> RGB and Component inputs should offer very similar picture quality in a
> domestic environment everything else being equal. It is possible to move
> from RGB to YPrPb component pretty much losslessly.
>
> Modern digitial TV production and recording (from broadcast VTRs to digital
> TV and DVD) all use component digital sampling of Y (luminance) and Cr/Cb
> (colour difference signals) and usually the CrCb colour difference signals
> (Cr is a weighted version of R-Y, Cb is a weighted version of B-Y) are sent
> at a lower horizontal (and often also vertical) resolution. This is better
> done in the YCrCb domain than the RGB domain. YCrCb is what is transmitted
> via digital TV or recorded on DVD. However conversion from YCrCb to RGB
> should be nearly lossless (only a bit of noise and possible rounding
> assuming the signal is "legal") - and most TVs have to convert from YPrPb to
> RGB for display anyway, so you are just moving the conversion process by
> using differnet types of interconnect. (RGB and Component are both clean
> component systems - they aren't going to differ from each other like
> S-video/composite will with RGB or Component - where S-video and RGB mangle
> the picture using sub-carrier chroma techniques which adds all sorts of
> nastiness)
>
> However in the realm of TV interconnect there is one major difference -
> YPrPb component connections are also used to carry a progressive standard
> definition or an HDTV interlaced or progressive signal to and from suitable
> kit. This is far less common for RGB SCART connections (and not really part
> of the SCART standard?) - more for the fact that HD and progressive have yet
> to make in-roads in Europe - so the US/Japanese component interconnection
> has become the de-facto HD/Progressive connection standard.
>
> So RGB SCART and Component should be pretty much identical in quality terms
> for a standard definition, non-progressive, connection - i.e. a normal
> set-top box or DVD to TV connection - and RGB should give excellent results.
>
> It is only when you get to progressive/HD that component connections are
> required rather than SCART. Probably not an issue for you.
>
> Also - in terminology terms - as I understand it - PrPb normally refers to
> analogue colour difference signals, CrCb their digital counterparts. U and
> V are often also used - though these really refer to a specific weighting of
> colour differences in PAL composite encoder/decoders - I&Q are rotated
> versions used in NTSC stuff?
>
> Steve

Thank you all for your help

[vortex]

> Ahh No... RGB is 3 color signals and component is 2 color difference
> with 1 luminance. RGB usually doen't have sync information either, where
> as component does. RGB can come with sync information on the green
> channel too. So as mentioned in the Link RGB is Red Green Blue and
> Component is (Y)Luminance, (U)Blue - Luminance & (V)Red - Luminance
> which is more correctly known as CAV (C)omponent (A)nalog (V)ideo.


Y is indeed lumianacnce and U is blue, but V is Red-Green.

It is simply a colour space, there are a heap more including CMY (and the
CMYK dirivitive), YIK, HSV. There are even a few lookup colour spaces such
as Pantone.

The YUV colour space does not include sync. When used with TVs the sync data
is transmitted on the Y channel, howeer RGB does the exact same thing on the
Green chanell.

There are plenty of Devices that output RGB component, the Strong 5390 (via
the SCART, but it is still component), the xbox, the PS2 and a pile of DVD
players I was looking at the other day (I allready have one, but why stop
looking...)

[240V Inflatable GW Bush Doll]

There is a big difference between RGB and component.

RGB stands for red, green and blue - primary colours. You can mix them all
together in different amounts and you can display a picture.

Component is your set top box, DVD player, VCR, X-Box, Playstation 2 and so
on. Hope this helps.

"Tom" <gekko71@yahoo.com> wrote in message
news:bf3974de.0406241748.113500aa@posting.google.c om...
> "Stephen Neal" <stephen.neal@nospam.as-directed.com> wrote in message
news:<cbed2a$1n5$1$830fa795@news.demon.co.uk>...
> > "Tom" <gekko71@yahoo.com> wrote in message
> > news:bf3974de.0406231741.b0e61cd@posting.google.co m...
> > > hello
> > > can someone give me a good explanation of the differences between RGB
> > > and component inputs. What is the preferred method and what is the
> > > best quality in terms of image. My TV has a scart connection with RGB
> > > but mentions nothing about component. I thought component was supposed
> > > to produce the best image but others tell me its RGB.
> >
> > RGB and Component inputs should offer very similar picture quality in a
> > domestic environment everything else being equal. It is possible to
move
> > from RGB to YPrPb component pretty much losslessly.
> >
> > Modern digitial TV production and recording (from broadcast VTRs to
digital
> > TV and DVD) all use component digital sampling of Y (luminance) and
Cr/Cb
> > (colour difference signals) and usually the CrCb colour difference
signals
> > (Cr is a weighted version of R-Y, Cb is a weighted version of B-Y) are
sent
> > at a lower horizontal (and often also vertical) resolution. This is
better
> > done in the YCrCb domain than the RGB domain. YCrCb is what is
transmitted
> > via digital TV or recorded on DVD. However conversion from YCrCb to RGB
> > should be nearly lossless (only a bit of noise and possible rounding
> > assuming the signal is "legal") - and most TVs have to convert from
YPrPb to
> > RGB for display anyway, so you are just moving the conversion process by
> > using differnet types of interconnect. (RGB and Component are both
clean
> > component systems - they aren't going to differ from each other like
> > S-video/composite will with RGB or Component - where S-video and RGB
mangle
> > the picture using sub-carrier chroma techniques which adds all sorts of
> > nastiness)
> >
> > However in the realm of TV interconnect there is one major difference -
> > YPrPb component connections are also used to carry a progressive
standard
> > definition or an HDTV interlaced or progressive signal to and from
suitable
> > kit. This is far less common for RGB SCART connections (and not really
part
> > of the SCART standard?) - more for the fact that HD and progressive have
yet
> > to make in-roads in Europe - so the US/Japanese component
interconnection
> > has become the de-facto HD/Progressive connection standard.
> >
> > So RGB SCART and Component should be pretty much identical in quality
terms
> > for a standard definition, non-progressive, connection - i.e. a normal
> > set-top box or DVD to TV connection - and RGB should give excellent
results.
> >
> > It is only when you get to progressive/HD that component connections are
> > required rather than SCART. Probably not an issue for you.
> >
> > Also - in terminology terms - as I understand it - PrPb normally refers
to
> > analogue colour difference signals, CrCb their digital counterparts. U
and
> > V are often also used - though these really refer to a specific
weighting of
> > colour differences in PAL composite encoder/decoders - I&Q are rotated
> > versions used in NTSC stuff?
> >
> > Steve
>
> Thank you all for your help

[flyinyereye]

"240V Inflatable GW Bush Doll" <240V@inflation.com> wrote in message
news:40dc05e1$0$18668$afc38c87@news.optusnet.com.a u...
> There is a big difference between RGB and component.
>
> RGB stands for red, green and blue - primary colours. You can mix them
all
> together in different amounts and you can display a picture.
>
> Component is your set top box, DVD player, VCR, X-Box, Playstation 2 and
so
> on. Hope this helps.

No it doesn't. You obviously have no idea. My STB does both RGB and
component, while my DVD player and TV both do RGB but not component.

Hope this helps.

[Michael Garibaldi]

vortex wrote:

>>Ahh No... RGB is 3 color signals and component is 2 color difference
>>with 1 luminance. RGB usually doen't have sync information either, where
>>as component does. RGB can come with sync information on the green
>>channel too. So as mentioned in the Link RGB is Red Green Blue and
>>Component is (Y)Luminance, (U)Blue - Luminance & (V)Red - Luminance
>>which is more correctly known as CAV (C)omponent (A)nalog (V)ideo.
>
>
>
> Y is indeed lumianacnce and U is blue, but V is Red-Green.

U is Blue minus Luminance
The point is that it's 'Component' is Luminance or (Green) with 2 color
difference signals. RGB is raw color information and Component is a
processed form derived from it for reduction purposes.
>
> It is simply a colour space, there are a heap more including CMY (and the
> CMYK dirivitive), YIK, HSV. There are even a few lookup colour spaces such
> as Pantone.
All of these are computer terms, the TV system uses RGB at it capture
and final reproduction. The camera system using a diachroic prism to
separate full spectrum light into RGB. CRTs, Projectors etc still
require separate R G & B signals at the final stage to reproduce the image.
>
> The YUV colour space does not include sync. When used with TVs the sync data
> is transmitted on the Y channel, howeer RGB does the exact same thing on the
> Green chanell.
>
> There are plenty of Devices that output RGB component, the Strong 5390 (via
> the SCART, but it is still component), the xbox, the PS2 and a pile of DVD
> players I was looking at the other day (I allready have one, but why stop
> looking...)
If the Strong 5390 uses the same as the 5290, it has RGB on the scart
not component. You can't use RGB with a YUV input as 2 color difference
signals are not Red and Blue. It does not have sync info on green
either. The Strong is a good example of Scart RGB, but most non computer
based display manufacturers are preferring to make Component YUV inputs
over RGB which leaves many Scart devices like the Strong incompatible.
>

[240V Inflatable GW Bush Doll]

lol

Your sarcasm filter isn't sensitive enough mate. Crank it up a bit for us
all.

"flyinyereye" <spam@spam.com> wrote in message
news:40dc1263$0$24750$5a62ac22@per-qv1-newsreader-01.iinet.net.au...
> "240V Inflatable GW Bush Doll" <240V@inflation.com> wrote in message
> news:40dc05e1$0$18668$afc38c87@news.optusnet.com.a u...
> > There is a big difference between RGB and component.
> >
> > RGB stands for red, green and blue - primary colours. You can mix them
> all
> > together in different amounts and you can display a picture.
> >
> > Component is your set top box, DVD player, VCR, X-Box, Playstation 2 and
> so
> > on. Hope this helps.
>
> No it doesn't. You obviously have no idea. My STB does both RGB and
> component, while my DVD player and TV both do RGB but not component.
>
> Hope this helps.
>
>

[240V Inflatable GW Bush Doll]

http://www.avforums.com/frame.html?http://www.avforums.com/forums/showthread.php?t=43445

"Tom" <gekko71@yahoo.com> wrote in message
news:bf3974de.0406231741.b0e61cd@posting.google.co m...
> hello
> can someone give me a good explanation of the differences between RGB
> and component inputs. What is the preferred method and what is the
> best quality in terms of image. My TV has a scart connection with RGB
> but mentions nothing about component. I thought component was supposed
> to produce the best image but others tell me its RGB.
>
> thnks
> tom

[Tony Prochazka]

> RGB and Component inputs should offer very similar picture quality in a
> domestic environment everything else being equal. It is possible to move
> from RGB to YPrPb component pretty much losslessly.
>
> Modern digitial TV production and recording (from broadcast VTRs to digital
> TV and DVD) all use component digital sampling of Y (luminance) and Cr/Cb
> (colour difference signals) and usually the CrCb colour difference signals
> (Cr is a weighted version of R-Y, Cb is a weighted version of B-Y) are sent
> at a lower horizontal (and often also vertical) resolution. This is better
> done in the YCrCb domain than the RGB domain. YCrCb is what is transmitted
> via digital TV or recorded on DVD. However conversion from YCrCb to RGB
> should be nearly lossless (only a bit of noise and possible rounding
> assuming the signal is "legal") - and most TVs have to convert from YPrPb to
> RGB for display anyway, so you are just moving the conversion process by
> using differnet types of interconnect. (RGB and Component are both clean
> component systems - they aren't going to differ from each other like
> S-video/composite will with RGB or Component - where S-video and RGB mangle
> the picture using sub-carrier chroma techniques which adds all sorts of
> nastiness)
>
> However in the realm of TV interconnect there is one major difference -
> YPrPb component connections are also used to carry a progressive standard
> definition or an HDTV interlaced or progressive signal to and from suitable
> kit. This is far less common for RGB SCART connections (and not really part
> of the SCART standard?) - more for the fact that HD and progressive have yet
> to make in-roads in Europe - so the US/Japanese component interconnection
> has become the de-facto HD/Progressive connection standard.
>
> So RGB SCART and Component should be pretty much identical in quality terms
> for a standard definition, non-progressive, connection - i.e. a normal
> set-top box or DVD to TV connection - and RGB should give excellent results.
>
> It is only when you get to progressive/HD that component connections are
> required rather than SCART. Probably not an issue for you.
>
> Also - in terminology terms - as I understand it - PrPb normally refers to
> analogue colour difference signals, CrCb their digital counterparts. U and
> V are often also used - though these really refer to a specific weighting of
> colour differences in PAL composite encoder/decoders - I&Q are rotated
> versions used in NTSC stuff?
>
> Steve


Hey, you seem to know your stuff. Can you come and fix my espresso
machine?

Tony
--
"Losslessly". Yes folks, this is C21.

[Tony Prochazka]

> RGB and Component inputs should offer very similar picture quality in a
> domestic environment everything else being equal. It is possible to move
> from RGB to YPrPb component pretty much losslessly.
>
> Modern digitial TV production and recording (from broadcast VTRs to digital
> TV and DVD) all use component digital sampling of Y (luminance) and Cr/Cb
> (colour difference signals) and usually the CrCb colour difference signals
> (Cr is a weighted version of R-Y, Cb is a weighted version of B-Y) are sent
> at a lower horizontal (and often also vertical) resolution. This is better
> done in the YCrCb domain than the RGB domain. YCrCb is what is transmitted
> via digital TV or recorded on DVD. However conversion from YCrCb to RGB
> should be nearly lossless (only a bit of noise and possible rounding
> assuming the signal is "legal") - and most TVs have to convert from YPrPb to
> RGB for display anyway, so you are just moving the conversion process by
> using differnet types of interconnect. (RGB and Component are both clean
> component systems - they aren't going to differ from each other like
> S-video/composite will with RGB or Component - where S-video and RGB mangle
> the picture using sub-carrier chroma techniques which adds all sorts of
> nastiness)
>
> However in the realm of TV interconnect there is one major difference -
> YPrPb component connections are also used to carry a progressive standard
> definition or an HDTV interlaced or progressive signal to and from suitable
> kit. This is far less common for RGB SCART connections (and not really part
> of the SCART standard?) - more for the fact that HD and progressive have yet
> to make in-roads in Europe - so the US/Japanese component interconnection
> has become the de-facto HD/Progressive connection standard.
>
> So RGB SCART and Component should be pretty much identical in quality terms
> for a standard definition, non-progressive, connection - i.e. a normal
> set-top box or DVD to TV connection - and RGB should give excellent results.
>
> It is only when you get to progressive/HD that component connections are
> required rather than SCART. Probably not an issue for you.
>
> Also - in terminology terms - as I understand it - PrPb normally refers to
> analogue colour difference signals, CrCb their digital counterparts. U and
> V are often also used - though these really refer to a specific weighting of
> colour differences in PAL composite encoder/decoders - I&Q are rotated
> versions used in NTSC stuff?
>
> Steve


Hey, you seem to know your stuff. Can you come and fix my espresso
machine?

Tony
--
"Losslessly". Yes folks, this is C21.

[Tony Prochazka]

In article <cbgjhp$9ge$1@pinah.connect.com.au>,
"vortex" <noone@nowhere.nul> wrote:

> > Ahh No... RGB is 3 color signals and component is 2 color difference
> > with 1 luminance. RGB usually doen't have sync information either, where
> > as component does. RGB can come with sync information on the green
> > channel too. So as mentioned in the Link RGB is Red Green Blue and
> > Component is (Y)Luminance, (U)Blue - Luminance & (V)Red - Luminance
> > which is more correctly known as CAV (C)omponent (A)nalog (V)ideo.
>
>
> Y is indeed lumianacnce

- sounds like some nasty fluorescent skin disease.

> and U is blue, but V is Red-Green.
>
> It is simply a colour space, there are a heap more including CMY (and the
> CMYK dirivitive), YIK, HSV. There are even a few lookup colour spaces such
> as Pantone.
>
> The YUV colour space does not include sync. When used with TVs the sync data
> is transmitted on the Y channel, howeer RGB does the exact same thing on the
> Green chanell.
>
> There are plenty of Devices that output RGB component, the Strong 5390 (via
> the SCART, but it is still component), the xbox, the PS2 and a pile of DVD
> players I was looking at the other day (I allready have one, but why stop
> looking...)


I'm both impressed and flummoxed by the expertise on show here and in
prior posts. This is stirring stuff, which rings true despite its
impenetrability to the lay reader. May I just add my own humble
perspective to the thread?

Humans come equipped with primary visual sensing arrays called retinas.
These arrays feature large numbers of three basic types of
colour-sensing cells which respond maximally to light wavelengths
commonly referred to as "red", "yellow" and "blue", owing to
photochemical peculiarities of the organic molecules contained therein.
All colour information which is capable of being sensed by a human
consists of relative proportions of these three basic points on the
electromagnetic spectrum. Note that each type of colour sensing cell has
positive, but diminishing, sensitivity to other wavelengths on either
side of its "optimal" colour, and there is some overlap between
different cell types. Hence our retinas are capable of sensing photons
with wavelengths between red and indigo.

An ideal output device (read "TV") will therefore be optimised to
project photons of light in these three wavelengths, mixed in suitable
proportions to simulate "visual reality" to the human viewer. Other
mammals with slightly different retinal physiologies would find the
information unrealistic or confusing, owing to said output device's lack
of optimisation for their own retinal peculiarities. (On the other hand,
they may just think "why doesn't the dickhead stop dribbling in front of
this flickering object and just refill my food bowl?")

I'm fascinated to read how various proprietary technologies deal with
the transfer of colour information from one device to another, and how
these transfer methods relate to human physiology. It's interesting to
guess (for that is the only option available in this forum) how the
concept of a "lookup colour space such as Pantone" might be
interpretable via the paradigm of the human retina. I suspect there are
several layers of meaning between my basic, physiologically skewed
conception of colour, and the technically-savvy diatribes elicited in
response to this thread's primary post.


Tony Prochazka

[Tony Prochazka]

In article <cbgjhp$9ge$1@pinah.connect.com.au>,
"vortex" <noone@nowhere.nul> wrote:

> > Ahh No... RGB is 3 color signals and component is 2 color difference
> > with 1 luminance. RGB usually doen't have sync information either, where
> > as component does. RGB can come with sync information on the green
> > channel too. So as mentioned in the Link RGB is Red Green Blue and
> > Component is (Y)Luminance, (U)Blue - Luminance & (V)Red - Luminance
> > which is more correctly known as CAV (C)omponent (A)nalog (V)ideo.
>
>
> Y is indeed lumianacnce

- sounds like some nasty fluorescent skin disease.

> and U is blue, but V is Red-Green.
>
> It is simply a colour space, there are a heap more including CMY (and the
> CMYK dirivitive), YIK, HSV. There are even a few lookup colour spaces such
> as Pantone.
>
> The YUV colour space does not include sync. When used with TVs the sync data
> is transmitted on the Y channel, howeer RGB does the exact same thing on the
> Green chanell.
>
> There are plenty of Devices that output RGB component, the Strong 5390 (via
> the SCART, but it is still component), the xbox, the PS2 and a pile of DVD
> players I was looking at the other day (I allready have one, but why stop
> looking...)


I'm both impressed and flummoxed by the expertise on show here and in
prior posts. This is stirring stuff, which rings true despite its
impenetrability to the lay reader. May I just add my own humble
perspective to the thread?

Humans come equipped with primary visual sensing arrays called retinas.
These arrays feature large numbers of three basic types of
colour-sensing cells which respond maximally to light wavelengths
commonly referred to as "red", "yellow" and "blue", owing to
photochemical peculiarities of the organic molecules contained therein.
All colour information which is capable of being sensed by a human
consists of relative proportions of these three basic points on the
electromagnetic spectrum. Note that each type of colour sensing cell has
positive, but diminishing, sensitivity to other wavelengths on either
side of its "optimal" colour, and there is some overlap between
different cell types. Hence our retinas are capable of sensing photons
with wavelengths between red and indigo.

An ideal output device (read "TV") will therefore be optimised to
project photons of light in these three wavelengths, mixed in suitable
proportions to simulate "visual reality" to the human viewer. Other
mammals with slightly different retinal physiologies would find the
information unrealistic or confusing, owing to said output device's lack
of optimisation for their own retinal peculiarities. (On the other hand,
they may just think "why doesn't the dickhead stop dribbling in front of
this flickering object and just refill my food bowl?")

I'm fascinated to read how various proprietary technologies deal with
the transfer of colour information from one device to another, and how
these transfer methods relate to human physiology. It's interesting to
guess (for that is the only option available in this forum) how the
concept of a "lookup colour space such as Pantone" might be
interpretable via the paradigm of the human retina. I suspect there are
several layers of meaning between my basic, physiologically skewed
conception of colour, and the technically-savvy diatribes elicited in
response to this thread's primary post.


Tony Prochazka