"Bob Parker"
** The DD5.1 35mm film system is clearly STATED to use a CCD camera whose images are processed - so not a line scanner.High effective shutter speeds ( even 10uS ) are well possible with CCD technology, as is operation with a few uS pulse of light.
Processing the "checkerboard" images into a data stream is then a simple DSP problem.
Let Occam's razor apply.
....... Phil
Google might be my friend, but search The data block is read by a 512 element charged coupled device (CCD), which is, in essence, a television camera. The output of the CCD is an analog video "picture" of the spots on the film. This is converted into the digital video domain at a rate which tracks the speed of the film. This video data is scanned for synchronization information and to determine where the four corners of the data block are located. If two of the corners are known, the position of the entire block is known and the proper location of the data bits is known. Determining the whether or not a real data spot exists and preventing false data from entering the process is best understood by imagining a piece of window screen being placed directly over the data block. The corner bits verify the proper Position for the screen. Looking at the "screen", one sees in the small square openings exactly where the spots should be. Using a digital version of such a screen, the data spots are identified and then sent to a "thresholding" stage for further enhancement. Based on the average density of the spots, a threshold value is determined, above which the spot is recognized as a "1" and below which, a "0". This stage reduces the possibility that a scratch could be mistaken for actual data and establishes what, on the film, is a spot and what is not.
I'm not sure if that clarfies anything or not. :-)
Bob
"Bob Parker
** Well, it sure as hell clarifies it ain't a line scanner - it's a camera........ Phil
I'm keeping an open mind until I get more info. I can't see how a CCD with only 512 photodetectors arranged as a square array could read a
60 x 60 dot array. It don't add up. To a journo, anything with a lens which responds to light is "a camera". ;-)Bob
** Wiki I quoted says ( in part) :
" A CCD scanner in the projector picks up a scanned video image of this area, and a processor correlates the image area and extracts the digital data as an AC-3 bitstream. These data are finally decoded into a 5.1 channel audio source. "
Pays one not to rely on fallible memory .......
....... Phil
If the sensor is a 512 element CCD then this would only be compatible with the linear sensor hypothesis as put forward by Jansen
"pjk" "Phil Allison"
** Hmmm - so someone used the old " drop of the K " trick to bamboozle everyone ?? ** Hah - two dimensions IS better than one.Flat Earthers, take heart.....
...... Phil
Phil I searche frepatents online for "dolby sound digital projector" and found this patent which would seem to support your view that the CCD was two dimensional. Also searching google 1992 and CCD confirms CCD od the order of 512K pixel were readily available at that time which is clearly sufficient.
United States Patent 5710752
That would explain everything!
Bob
Your search - "Phil Allison+Tourette's Syndrome" - did not match any documents.
Just do a Google Groups search on "Phil Allison+Tourette's Syndrome". You'd be surprised what you come up with.
Sure you tried Google under Groups? My search got 152 results.
"Alan Rutlidge"
If you have the time for any of the above, perhaps time is hanging heavily on your hands. You could do good deeds, visit the sick, make wooden toys for poor children.
Forgot to make it 'groups'. :-(
Hmmm... I have read the group for a while so I know perfectly well what to expect from you but what I wonder is, are you really too scrambled in the head to realize you are wrong or you are not man enough to admit it.
"ER"
** FUCK OFF -you illiterate, Bloody MORON !!!
...... Phil
yeah, I reckon it's something like this:
trying to take still images of moving film seems tricky.
Bye. Jasen
Actually TT and I are both working up to self funded early retirement. Works for me. :-)
Thanks for the info. :-) Fax machines don't take still photos of the moving document then electronically scan them... they just digitize a single one-pixel-wide strip as the document goes past. The same with document scanners except that the sensor is normally the moving part. I can't see why it would be any different with rows of optical data bits on a moving film, letting the linear motion of the film do the 'scanning'.
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