Ok, again I've been arguing with my flatemate over trivial things, and this time google can't seem to find the answer... How many colours does a TV picture have? afaik analog tv would be analog (duh) so you can't really put a figure on it (depends on the camera I suppose). And from what I can find out digital tv is at least 16bit. He claims standard tv is 256...or maybe less.
Well yes, any monitor is made up of green red and blue, but the question is how many possible combinations there are.
AFAIK analogue is analogue with no discrete levels in the colour burst so the technically true answer is infinate (although in practice this number is significantly lower, infinate/8 or somthing *grin*) Don't know about digital, sorry.
Trouble is he knows just enough to be annoying: me: It's analog so theoretically it's an infinite no. of colours him: But it can't be infinite in reality, and I read that it only does 256 colours /me Picks up nearest sharp object.... Trouble is it doesn't seem to say anywhere 'A tv can display x number of colours', except sometimes in the bumf for LCD tv's where they boast that it can display up to 24bit. This is starting to bug me now
LCD's are digital if I'm not mistaken. An analogue system can display a virtually infinite number of colours, so working on purely analogue systems(analogue ariel, tv signal, and tv) there should be a near infinite number of colours.
256 colours? Please... have you seen how bad GIFs can be with their limited palette? While the DACs in the television company's computers might only broadcast to a certain degree of precision (I imagine it's quantised to 16 bits or less to make real-time processing easy), the number of colours that an analogue TV can display is mch larger than 256... since the signal is analogue, it's theoretically restricted due to the the threshold of perception of the human eye. There is probably a limit imposed by the fine control of the electron guns, but I'd imagine that it'll still be in the thousands of colours. LCDs have a more finite limit because their pixels are controlled by a transistor matrix, which - obviously - is an inherently digital device. 24-bits sounds right, since current LCD tech would be designed to match the highest possible colour output we have. "32-bit" colour is in fact 24 bits with 8 alpha transparency bits stacked on top.
A lot more than 256, but nowhere near infinity, according to this lad. He's talking about designs to be shown on TV, but I imagine the same limitations apply to normal broadcast stuff - no true black or white. Actually with analogue it is an infinite number it can show, but there are another infinite number it can't cope with, so the answer is 37.
Indeed, I know its not infinite, but I figured, since it could be any RGB combination, that the total would be in the low billions most likely, if not higher, so virtually infinite is a good enough aproximation.
well with rgb, its 255^3 or about 16 million colors which is a number commonly used to say how many colors something shows so if TVs use less than rgb, its less than 16 million (according to the guides recommendation of between 16 - 236, its 220^3 or about 10 million) however this is all pointless since ntsc is just the standard for broadcast, and the tv isnt actually the limiting factor for the amount of colors a tv can show. so... do you want to know how many colors a signal can send to a TV, or how many colors a tv tube can show? :/ i could also be wrong but in the end, it most certainly isnt 256 colors
specofdust, see my edit. I suddenly remembered infinity - 37 = infinity. You can't have "almost infinite" (or "almost unique"). Note Plasma TV advert:
Your all looking at analogue wrong. Granted, the info cpemma rpovided is a conversion of a 256 bit level to an anologue signal. The 'levels' in a 256bit conversion is what the article talks about, the fact that NTSC does not handle the outer limits of the color spectrum. Now think of this. Its not that the analogue goes to infinity on the outter edges. Its the transition from one level to another. Yes, there is RGB, but each of these three colors differs in brightness causing more colors. In a digital system, there are distinct levels. Each bit conicides to a level. Change the bit value by one, and you suddenly 'jump' to a higher brigtness with no smooth transition from the first level to the next. Analogue means you have an infinite amount in between each of those digital levels . To be honest, the TV system has some mechanical limitations, so there should be a theoretical finite number of brightness levels determined by the design of the system, but also in retrospect the system itself is kind of sloppy and even though the signal would be the same, the TV cannot really truly replicate the signal the same exact way twice. So, by accident, the poor design of the system means that since even repetitive input signals would not truly be replicated and be somewhat 'off' each repitition, you really do get an infinite amount of brightnesses for each R, B, anf G, and hence the mixtures of the three would also be infinite.
of course television has limited colors, that's why people on TV wear makeup, because they don't look "Natural" without. they also can't wear brightly colored striped ties, 'cause they fark with the signal and cause a "barber pole" effect. and of course, we're moving to "HD" tv, which supposedly had more color definition.
That's to compensate for the artificial studio lighting, an outside broadcast looks as natural as a daylight photo. Leastways it does on PAL. And so politicians don't go shiny with sweat when they're asked awkward questions.
I spoke to him this morning and the guy is absolutely convinced (to the point of shouting) that: "tv started off with 2 colours, then went to 16, now it has 256, why do you think we use 256 shades of grey rather than a different number". Errr, coz it's a power of 2 maybe? Damn, he's not a stupid bloke but he really does have this idea in his head, I recon I'll have to find a BBC engineer or something to put him straight. I did find somewhere that the human eye can't tell the difference between colours well enough to make use of 48bit colour, so more than that is effectivly infinite (coz we can't tell the difference). started off with two colours my arse, Baird's tv had shades of grey ffs And I just did a 'Count colours used' on a vid recorded of analog tv and it came to just under 28,000, but that's not really proof I guess.
i'd say its 16million colours the same that is in the visible spectrum Edit: i found this From this site http://bugclub.org/beginners/history/MonitorsHistory.html
Tell him to FF off. Any digital display is a different animal, as others have pointed out. Then it comes down to how many bits you want to use to describe a colour, which will be limited by processing speed, economics and the simple fact that it's not worth going to extremes, most married blokes are colour-blind anyway (according to their wives). With analogue I'm sure quantum comes in somewhere, it usually does.
