Domain: jproc.ca
Stories and comments across the archive that link to jproc.ca.
Comments · 8
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Blur problem more than slow LCD transitions
https://www.blurbusters.com/fa...
There is more to the motion blur problem than the slow transition times of LCD pixels. Newer monitors have much faster transition times and the problem is still there.
What I think is happening is that the CRT is producing a kind of impulse sampling of the moving image whereas the LCD is producing zero-order hold (square-step, see https://en.wikipedia.org/wiki/...) output. The human visual centers appear to perceive the "strobed" image of the CRT as smooth motion, the "change-and-hold" image of the LCD as blurred, even at high frame rates and with rapid pixel response.
The reason I say "kind of impulse sampling" is that the CRT does not flash a sequence of static images the way a film movie projector does. Rather, the CRT conducts a continuous raster scan, with a short blanking during the retrace. Each line of the image gets strobed at the time the scan reaches it, but each line is strobed at a different time instead of the whole image all at once as with a film projector.
I believe it is that scanning that accounts for the "soap opera effect" of video content recorded on video tape instead of on film. This is already a long while ago that a local TV station had a show-and-tell of this new thing called HDTV at our Engineering campus. The Engineering profs were oohing and ahh-ing about what they thought were amazing images, but I was pointing out the image artifacts (easier to spot in HD!) to the broadcast engineer from the TV station, and finding a receptive audience, he went on at length to explain the difference between Homicide, Life on the Streets, shot on video tape and having the soap opera look, compared with Law and Order, which he explained was shot on 35 mm film and then scan-converted for TV broadcast.
So, even if the CRT scanned mode of projection differs from the flashed-image mode of film projection, apparently recording the image on film, which records a sequence of still pictures, has a better look than video tape, even when film is played back on a CRT.
The other problem is that most people viewing video think that HD on a widescreen LCD looks fantastic and don't know what us motion-blur worriers are complaining about. This population includes engineers developing TVs and computer monitors. The only people complaining, it seems are hard-core gamers along with people who have seen the Kay 5500 Sonograph http://jproc.ca/rrp/sonagraph_..., a scientific instrument used in speech science that used a DSP to drive a CRT (at VGA resolution!) that produced a truly remarkable visual effect of a "voice print" rolling past the screen with zero motion blur -- the later software spectrum analyzers producing un-synched scrolls to LCD monitors of much higher frame rate look terrible by comparison.
With respect to the awful motion blur of LCDs, which other posters here is telling me in not cured by video interpolation, there is an element of what Robert X Cringely described in Accidental Empires, when (back in the day), a techie gushed about the desktop publishing revolutions, showing off the font quality of LaTeX printed at 300 DPI on a LaserJet II, which Cringely looked at in dismay in comparison to what the publishing industry got from photo typesetting.
DPI and frame rate are important, but if the community is at all serious about further advances in video, especially VR, engineers are going to have to take the physiology of human vision and the motion blur problem into account.
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AUTODIN
http://en.wikipedia.org/wiki/Automatic_Digital_Network
http://jproc.ca/crypto/autodin.htmlI managed a few Technical Control sites long ago. We could route normal telegrams on the system with a little creative address routing.
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Re:Isn't that kind of the point?
"The problem with this is that those drones have encrypted radios and if they didn't get wiped in time closely guarded encryption keys."
Keys expire and systems can be fitted with a variety of controlled and automatic "zeroize" switches.
Those problems have been dealt with for decades.
I was keying these every night in 1982:
http://jproc.ca/crypto/ky28.html
"Caption: The black block sitting on top of the KY-28 is the KYK-38 and it plugs into the front of the unit. This device is on display at the MARCOM Museum in Halifax. (Photo by Jerry Proc)
The device was also fitted with a internal shock sensor. If the aircraft crashed, the resulting 'G' forces would trip this sensor thus resetting the key. "
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High Quality Encryption
This page lists many High Quality Encryption devices.
http://www.jproc.ca/crypto/menu.html
Look at the KGV series -
Re:This just in
http://www.jproc.ca/crypto/ag_crypto_history.html Cryptoteknik did have links back to Sweden.
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Re:Insecure systems
Except that Windows has such a cult following that it's likely the authorities will turn a blind eye to the incident. Take the case where Windows somehow got onto base computers in Afghanistan [usnews.com] and were subsequently owned by malware letting still more outsiders into the network. No one's been prosecuted publicly despite there certainly being a paper trail leading to the culprits.
You apparently have no clue how DOD classified networks work such as SIPRnet or JWICs. Anything classified has no connection to the unclassified internet. The SIPRnet and JWICS system passes though a KG-175, which in turns encrypts the traffic, to go though the normal network. If for example a windows SIPRnet, or JWICs system gets comprised with spyware. The only one who could touch these systems is people on the SIPRnet or JWICS. Just because the machine is comprised doesn't make the computer decide to send unencrypted data or open holes in the network, since any traffic leaving the network has to go though the KG-175. Now if some idiot user decides to connect a classified system to network, that's a much bigger issue that they call data spillage.
Any computer not classified is essentially on the NIPRnet (or unclassified network) for example, but the only data that is allowed on it is up to sensitive information such as SSNs, random forms, and TPS reports. Even flight schedules are not supposed to be NIPRnet. -
Re:"low frequency navigation"
Loran (90-110 khz) is still operational, but if you want real low frequency navigation, you want Omega (10-14 khz). Omega ceased operations in 1997, but while operational its signals had a wavelength of around 25 kilometers, and were transmitted by 8 stations scattered across the globe. By receiving signals from three stations, am Omega receiver could locate a position to within 4 nm using the principle of phase comparison of signals. This made Loran-C (accuracy better than
.25 nm) look damn accurate in comparison. These shortcoming aside, it was the first worldwide radio-navigation system. -
Re:Old newsInteresting about the interference attacks. What stops Loran C (or any other radio system) from being interfered with? A small EMP from a tiny nuke would wipe out all radio navaid systems in the neighbourhood.
Also, it appears that Germany and Norway have withdrawn from the Loran agreement. Is Loran clinging on by it's fingernails?
I also see that they've killed Decca for pretty much the same reasons that Loran C seems to be going out of business. Decca was, for many years, my primary radio navaid - being on a UK ship meant that DECCA was used first and I well remember using it. Comparing the two at it's height, DECCA always had more coverage.
I think that a good lighthouse system would provide excellent backup system.