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Why is TV Static Monochrome? | Nostalgia Nerd - Duration: 7:20.For most of us today, television static is a thing of the past.
With digital tuners, HDMI connections and flat screen TVs, even if there is interference,
we don't get a chance to see it, as the television circuity boldly saves us from this ordeal.
Early TVs adopting digital tuners would actually spoof this snowy noise themselves, so as not
to disturb people, but otherwise we get a blank screen, maybe a message hovering about,
politely informing us of the lack in coherent signal.
Thankfully the message never, ever, directly hits the corner.
If it did, well, I hate to imagine the consequences....
*EXPLOSION*
But people like me, and probably you, still have to deal with garbled screens of static
on a regular basis, especially for older consoles which only provide an RF output, and even
then, it's non uncommon to get quite a noisy picture.
But given we're using colour TVs for the most part, producing a colour image, why on earth
is the TV static only black and white?
Well, let's start with fundamentals.
Why do we even get this static fuzz?
Well analogue televisions try to amplify any signals they receive, so if there isn't a
strong enough signal from a TV mast, or a modulator being sent into the TVs receiver
at the frequency it's currently tuned to, it will instead amplify whatever electromagnetic
signals it picks up.
These signals can originate from a number of sources including residual signals spilling
over from the big bang - cosmic microwave background radiation, man made signals buzzing
around the air, atmospheric sources, but mainly, it's Johnson noise (not that kind).... essentially
thermal RF noise generated by the components of the TV itself.
Because of the random nature of these signals, your television receiver interprets it as
as a garbled fuzz of noise, presented as a swarm of seemingly frantic ants on screen.
If it wasn't random you'd perceive patterns in this dissaray, and of course an ordered,
stronger signal would pretty much cancel out this noise altogether and present us with
a coherent image.
The reason the colour of this snow isn't as random as the patterns themselves is due to
the way televisions and transmissions have evolved.
Let's look at segment from a PAL video signal.
From left we have the end of a video scan line.
This constitutes a single line drawn across your television by an electron gun (on cathode
ray tube televisions at the least).
We then have the front porch, this is here to prevent interference between individual
lines.
Next is the horizontal sync pulse, which signifies the start of the next scan line.
This is followed by the back porch, which restores the black levels and also leads onto
the colour burst.
Now this is the important part, as it effectively tells our television how to create the colour
image.
The colourburst synchronises a subcarrier signal containing the colour data.
The encoded format of which relies on the YUV colour space, providing chrominance data
to go with the luminance value.
The chrominance data carries blue and red values, which are substracted from the luminance
figure to provide a value for green.
Given that monochrome televisions rely on the embedded luminance data to identify how
bright each part of the image is, delivering colour information outside of each visible
scanline, ensured compatibility with monochrome TV receivers, which simply ignored it - an
essential caveat during its introduction.
It also required far less bandwidth than using 3 separate signals to transmit Red, Green
and Blue components.
The colour subcarrier itself reduces bandwidth further by only providing half the vertical
resolution on every other scan line.
We don't perceive any different as our eyes see a constrasting monochrome image in more
detail than a colour one.
But the upshot is, until your TV receives and recognises this information, it's essentially
running in Black & White mode.
Each time it draws a line, it looks for the subsequent colourburst pattern, but doesn't
find it, and moves on.
It hasn't been given the information to create a colour image.
So although you may expect the random signals & fluctuations received & displayed on an
untuned television to be interpreted as a multitude of different colours, they're simply
not delivered in a fashion which the TV can decode into colour information.
At this point, the decoder is really still expecting a 1960s B&W film to be streamed
into living rooms.
So, what about the sound?
Well, in an untuned set, the sound is as random as the on screen image, with the set amplifying
all those floating no good signals.
With a tuned channel, the sound data is held on a frequency with a fixed off-set.
This is why even if you can sometimes tune into a picture spilling over from its broadcast
frequency, it may may still have no sound.
The receiver won't find the sound data until the picture is tuned to the correct frequency
and the off-set is matched up.
Now, I've been talking about the PAL system here and although there are small differences
from TV protocol to TV protocol, the reason is very much the same.
NTSC for example, works on an almost identical principle, but with a different colour subcarrier
frequency.
This is why when we play an NTSC game or video over here, we get a black and white image....
again, the TV has no idea on what colours to paint over the image.
Over in France, their SECAM protocal encoded colour signals in FM rather than relying on
a colourburst sync.
But regardless, where-ever in look, the decoders need to be able to find suitable colour information
to decode, before it can be presented to our eyes.
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Why do you Love Dogs so Much? - Duration: 2:25.-------------------------------------------
Why creating AI that has free will would be a huge mistake | Joanna Bryson - Duration: 7:52.First of all there's the whole question about why is it that we in the first place
assume that we have obligations towards robots?
So we think that if something is intelligent, then that's their special source, that's
why we have moral obligations.
And why do we think that?
Because most of our moral obligations, the most important thing to us is each other.
So basically morality and ethics are the way that we maintain human society, including
by doing things like keeping the environment okay, you know, making it so we can live.
So, one of the way we characterize ourselves is as intelligent, and so when we then see
something else and say, "Oh it's more intelligent, well then maybe it needs even
more protection."
In AI we call that kind of reasoning heuristic reasoning: it's a good guess that will probably
get you pretty far, but it isn't necessarily true.
I mean, again, how you define the term "intelligent" will vary.
If you mean by "intelligent" a moral agent, you know, something that's responsible for
its actions, well then, of course, intelligence implies moral agency.
When will we know for sure that we need to worry about robots?
Well, there's a lot of questions there, but consciousness is another one of those
words.
The word I like to use is "moral patient".
It's a technical term that the philosophers came up with, and it means, exactly, something
that we are obliged to take care of.
So now we can have this conversation.
If you just mean "conscious means moral patient", then it's no great assumption
to say "well then, if it's conscious then we need to take care of it".
But it's way more cool if you can say, "Does consciousness necessitate moral patiency?"
And then we can sit down and say, "well, it depends what you mean by consciousness."
People use consciousness to mean a lot of different things.
So one of the things that we did last year, which was pretty cool, the headlines, because
we were replicating some psychology stuff about implicit bias—actually the best one
is something like "Scientists Show That A.I.
Is Sexist and Racist, and It's Our Fault," which that's pretty accurate, because it
really is about picking things up from our society.
Anyway, the point was, so here is an AI system that is so human-like that it's picked up
our prejudices and whatever… and it's just vectors!
It's not an ape.
It's not going to take over the world.
It's not going to do anything, it's just a representation; it's like a photograph.
We can't trust our intuitions about these things.
We give things rights because that's the best way we can find to handle very complicated
situations.
And the things that we give rights are basically people.
I mean some people argue about animals, but technically, and again this depends on whose
technical definition you use, but technically rights are usually things that come with responsibilities
and that you can defend in a court of law.
So normally we talk about animal welfare and we talk about human rights, but with artificial
intelligence you can even imagine itself knowing its rights and defending itself in the court
of law.
But the question is, why would we need to protect the artificial intelligence with rights?
Why is that the best way to protect it?
So with humans it's because we're fragile, it's because there's only one of us.
And I actually think—this is horribly reductionist, but I actually think—it's just the best
way that we've found to be able to cooperate.
It's sort of an acknowledgment of the fact that we're all basically the same thing,
the same stuff, and we had to come up with, the technical term again is equilibrium, we
had to come up with some way to share the planet, and we haven't managed to do it completely
fairly (like 'everybody gets the same amount of space'), but actually we all want to
be recognized for our achievements so even completely fair isn't completely fair, if
that makes sense.
And I don't mean to be facetious there, it really is true that you can't make all
the things you would like out of fairness be true at once.
That's a fact about the world; it's a fact about the way we define fairness.
So, given how hard it is to be fair, why should we build AI that needs us to be fair to it?
So what I'm trying to do is just make the problem simpler and focus us on the thing
that we can't help, which is the human condition.
And I'm recommending that if you specify something, if you say okay this is when you
really need rights in this context, okay once we've established that, don't build that,
okay?
A lot of people this rubs them the wrong way because they've watched Blade Runner or
AI the movie or something like this.
In a lot of these movies we're not really talking about AI, we're not talking about
something designed from the ground up, we're talking basically about clones.
And clones are a different situation.
If you have something that's exactly like a person, however it was made, then okay,
then it's exactly like a person and it needs that kind of protection.
But even biological clones, even if you just want to clone yourself, at least in the European
Union, that's illegal.
I'm not sure about in America.
I think it's illegal in America too.
But people think it's unethical to create human clones partly because they don't want
to burden someone with the knowledge that they're supposed to be someone else, that
there was some other person that chose them to be that person.
I don't know if we'll be able to stick to that, but I would say that AI clones fall
into the same category.
If you're really going to make something and then say, "Hey, congratulations, you're
me and you have to do what I say," I wouldn't want myself to tell me what to do, if that
makes sense, if there were two of me!
I think we'd like to be able to both be equals, and so you don't want to have—an
artifact is something you've deliberately built and that you're going to own.
If you have something that's sort of a humanoid servant that you own, then the word for that
is slave.
And so I was trying to establish that look, we are going to own anything we build, and
so therefore it would be wrong to make it a person, because we've already established
that slavery of people is wrong and bad and illegal.
And so it never occurred to me that people would take that to mean that "the robots
will be people that we just treat really badly.
" It's like no, that's exactly the opposite!
So, I already mentioned that if somebody did manage to clone people somehow, which I don't
believe this is ever going to work but people do talk about it and people spending tens
of millions of dollars on it, "whole brain uploading".
So I don't believe it's possible.
I don't think it's actually computationally tractable, but if that were to happen then
I would be there saying, "Yes this is a person".
But how can we stop that the same way we stop human cloning, which is just to say, "Don't
do that"?
And particularly with AI my point is that it shouldn't be a commercial product.
So if somebody does this in their basement or something well then we have a few exceptions,
but I'm much more concerned about people mass producing such things.
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Meghan Markle's coat of arms: why is the crown around the bird's neck? - Duration: 2:28.Meghan Markle's coat of arms: why is the crown around the songbird's neck? It's nothing sinister â€" there is a royal explanation… The internet was left stumped after Meghan Markle's new coat of arms was released last week, with many quick to point out that the songbird's crown is around its neck and not on its head
Some took to Twitter to share their concern, noting that the bird looked "distressed" and as if it was being "strangled" by its headpiece
But the explanation is simple. There is nothing sinister or negative about the design, which was approved by the Queen beforehand
When a person marries into the royal family, the crown on their animal is drawn on their neck, while those who are born royal have a crown depicted on the animal's head
Hence, why Meghan's songbird wears a crown around its neck; the bird also has an open mouth, to represent the importance of communication
When the Duchess of Cambridge married Prince William, Kate was represented in the couple's conjugal coat of arms by a unicorn wearing a crown around its neck
And when Princess Diana wed Prince Charles, her animal, a griffin, was also depicted with a crown around its neck
Princes William and Harry's coat of arms, meanwhile, which they were granted on their 18th birthdays, show lions wearing the crown on their head
MORE: Harry and Meghan's royal wedding seating plan revealed! Meghan's coat of arms was unveiled on Friday, designed and approved by Her Majesty and Mr
Thomas Woodcock, Garter King of Arms and Senior Herald in England, who is based at the College of Arms in London
Meghan, 36, worked closely with the College of Arms throughout the creative process
MORE: See Meghan's brilliant response to friend who asked, 'Do I bow to you?' The Duchess of Sussex's design is steeped with personal touches
The blue background of the shield represents the Pacific Ocean off the California coast – Meghan was born in Los Angeles – while the two golden rays across the shield are symbolic of the sunshine of her home state
The three quills on her shield represent communication and the power of words. Beneath the shield on the grass sits a collection of golden poppies, California's state flower, and wintersweet, which grows at Harry and Meghan's London home, Kensington Palace
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