h a l f b a k e r yI think this would be a great thing to not do.
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In the "UK", if you use the IPlayer you have to pay the
colour TV licence rather than the black and white one.
This is unfair if you don't care about colour, and could
be easily remedied as follows.
There could be an app and a version of the IPlayer
which only shows BBC1 programmes in 405-line
B&W.
The other channels are unavailable because they were
never broadcast on VHF TV (which was switched off in
1985). It would have the further advantage of saving
bandwidth. A 405-line picture is equivalent in modern
terms to something like 155i, although it allegedly has
better horizontal resolution than PAL for monochrome
pics. Given a 4:3 aspect ratio and sixteen-level
greyscale, even a bitmapped frame would be only 16Kb
of data. Hence a 405-line Iplayer app on a pay as you
go smartphone would be much more practical and
cheaper than the current IPlayer.
There is an argument to be had that if you need a TV
licence for the IPlayer you also need it for binoculars
and periscopes, so the average British household, with
its pay as you go smartphone, periscope and binoculars
but no TV set or internet connection, could really
benefit from this.
Tektronix 4010
https://en.wikipedi...wiki/Tektronix_4010
A great advance, as they ran on kerosene rather than coke ... no stoker was needed. [8th of 7, Nov 06 2018]
Vector-Rendered Cartoon Channel
The_20Vector-Rendered_20Cartoon_20Channel
[hippo, Nov 06 2018]
[link]
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By the Beeb finding a way to block the cones in the
eyes, a simple monthly dose of an enzyme that
reverses that blocking, they will be richer than
Creosote - nobody tell them this. |
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Would you pay an even cheaper licence fee if you used the app which simulated John Logie Baird's mechanical television? - or the app which converted TV programmes into 19th century "Magic Lantern" shows? |
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I think I'd actually pay more for that, [hippo]. |
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More ValvePunk than Steampunk, but still [+]. |
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Also available, the app which converts your TV show
into a Bayeaux-style tapestry, scrolling slowly and
silently past the viewer |
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Presumably controlled by punchcards? |
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A rotating drum akin to a musical box would be better. |
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// Bayeaux-style tapestry // |
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The Bayeaux "tapestry" is in fact an embroidery, not a tapestry; the production processes are quite different. |
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I like it, The Bayeux Embroidery of 1068 |
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I like this a lot, I'd use it too. Going black and white is a
great way of halving (at least) the data requirements.
Going low (ish) res I assume 405 lines would be 540x405?
which is about 10-fold less data than the HD standard, so
you're at 1/20th the color HD equivalent. That's before all
the various compression algorithms. I don't fully
understand compression algorithms, a few quick tests
with some image stacks of my own seem to show
compression ratios better for color... hmm. Either way,
most compression works better for small resolution. |
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I'd use this feature because many of the programs I watch
benefit little from the extra information transmitted, I
can get annoyed at Borris Johnson* just fine in B&W.
Conversely, I think there is an opportunity for increased
quality. The contrast ratio for film, even the old stuff can
be >70,000:1 so there's more than 16 Bit information
there. Maybe you'd like to watch Casablanca in 16 Bit
black and white rather than some hacked together
scanned to color and compressed version? Or maybe low
res and 60fps would be more suited to the type of
program, lots of sports are better appreciated at high
time resolution. Snooker not so much. |
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*John Major is greyscale in real life. |
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// 405 lines would be 540x405? // |
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Actually, much less. The horizontal resolution of a 625-line PAL signal using a 4.433MHz chroma subcarrier (phase modulated) is only about 300 lines; the true vertical resolution wasn't 625 either, as there was a "guard band" at the top (where the teletext signal was piggybacked) and bottom of the raster. |
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The 405 line signal used the same 6Mhz-ish sound subcarrier which imposes an upper limit on bandwidth, but due to the limitations of the technology of that era the actual horizontal resolution delivered "on screen" was only about 200 - 250 lines. |
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Since the CRTs had a 4:3 aspect ratio, this actually made things worse by stretching the X-axis, where the resolution was worst; a vertically scanned tube would have been able to deliver a more uniform granularity. Since the scanning was electronically driven, it's trivially simple to exchange the X and Y axes, and put the better resolution across the wider aspect of the tube. No-one thought of doing that, though. |
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Interestingly, the original Baird mechanical system (only about 30 lines resolution) also used vertical scanning. One of the first images transmitted was of a rather ugly wooden puppet (or maybe it was John Major - even with current 4k/3D resolution, it would be impossible to tell the difference). |
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Oh, and interlace... no, let's not go there. |
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405 went out on a VHF carrier, unlike the 625 line UHF system, which further restricted bandwidth (and available channels) but did give rather better coverage, resulting in a lower up-front capital cost for building transmitters (with a bigger footprint, fewer were needed, and VHF was less technically demanding than UHF). |
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How about just one wigglely line that outlines stuff? |
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So you'd get the outline of George Alagiah, and the
audio? |
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Ideally that option would come with a sharpened pencil, so that after perforating you eardrums you could stab your own eyes out too. |
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Early Tektronix CAD terminals <link> used a high-persistance phosphor with a "diddle yoke" (no, we haven't made that up) to draw the image on the CRT just like an Etch-A-Sketch (except rather faster) and then a "flood" gun to maintain the visibility. The flood gun could also be used to wipe the image as the terminals were very large and heavy, meaning that turning them face down and shaking them to erase the picture was a difficult and labour-intensive process. |
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I've just checked, we have a couple of microscopes that are
happy scanning those pixel numbers at the right kind of
rates. That's scanning mechanically with galvo/mirror
combos. All I have to do is get a small fluorescent screen
and a way of modulating the laser intensity at microsecond
resolution, which is probably doable with a lot of money.
Less than $2 million and I can make a single color
mechanically scanned 1" TV! Logie-Baird was right after all,
just needed nicer mechanical gear. |
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Really ? How unpleasant ... try asking at a pharmacy, they do all sorts of soothing creams for that sort of problem. |
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This idea reminds me that I did, when younger*, use my Mammod steam engine to make a steam-powered cinema which slowly scrolled a roll of paper with a continuous story across the screen.
[* redundant I suppose - everything in the past tense is either when I was younger or before I was born] |
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Sounds like a good idea if you're heavily into 'film noir' ;-) |
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ZX81 in FAST mode made me irritable after a short
period of time but I never had a seizure. I was
wondering at the time if I was epileptic but I turned
out not to be. |
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Life's full of little disappointments, [19th]. |
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