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UK to Build Network of 150 Digital Cinemas
mikael writes "According to this article at the BBC, a network of 250 digital screens in 150 cinemas across the country is being planned. Each film is losslessly compressed from 1 Terabyte down to 100 Gigabytes and encrypted onto a portable hard disk drive with a key unique to each cinema, which is then delivered to the cinema. Each cinema projector will be capable of showing films at resolutions of 2048 x 1080 pixels. "The key benefit is the distribution and screening of documentaries, British and foreign language films, as making a digital copy is considerably cheaper than spending over £1500 pounds to make a copy of a single film". Other benefits include better picture quality and the ability to show more films each day." The UK Film Council has a brief overview of the project as well.
Film canned at 3000DPI is assumed to have all useable details captured. If the film this is replacing is 35mm (1 x 1.5 inches)then a resolution of 3000x4500 is required for replacement. 2048x1080 falls a bit short.
Blessed are the pessimists, for they have made backups. -- 0 1 My two bits
It says "visually lossless". That is marketingspeak for "awful quality but no man in the street will notice".
Compare to digital tv.
Um, one slight problem. If you shoot digital and project digigtal, the final projected image is what you shot in the camera with an extra compression step on top.
If you shoot 35mm film, you get your negative, you cut the negative, you create a duplicate of the negative, then you create more duplicate negatives from that, then you finally create prints from those duplicate negatives. So by the time it gets to the cinema screen it's not unusual for a 35mm print to have gone through four or five _analogue_ copying stages from the original film negative.
As a result, the resolution of a final 35mm print is almost certainly substantially less than 2048x1080, whereas digital holds that resolution from start to finish (absent crappy compression schemes).
1) Original Negative
2) Positive Negative (copy on negative masked stock)
3) Dupe Negative (negative again) (digital editing here)
4) Copy Negative (positive)
5) Print Negative (shipped to theatres)
And no, you still have lots of resolution left at that point. I know people that have made the films you speak of, and matching curves between series was one of their most prized accomplishments.
(yes I worked for Kodak)
Are there such things as video projectors that accept an encrypted stream of data?
/. summary said, but near-lossless, probably a Fraunhofer MP4 encoding set to a medium to high quality setting.
Yes, which is what these systems will be using. Fraunhofer-gessellschaft (of MP3 encoder fame) is the technology behind these projectors. The stream is encrypted the entire length of the data path until it hits the electronics driving the LCD screen. Each server has a key built in, supposedly impossible to recover without destroying the system. Each film to be distributed is encrypted with both a master key, and the private half of the projector's key. There are several stages of decryption, allowing a mostly uncompressed and decrypted stream to be presented to the final stage electronics. The decryption at the projector stage is lightweight, as it is less likely to be subjected to a significant cryptographic attack because it relies on having fully authenticated equipment elsewhere in the chain.
The servers regularly contact an authentication centre, so that audits can be made as to the number of showings. The servers also come with tamper-resistant housings which then disable the system until it can once again contact the auth centre. There is a bunch of other security stuff, the projectors are never sold, but only licensed to the theatre for a fixed time and have to be returned or inspected at regular intervals.
From the article, it sounds like they only have the "medium" quality screens going in, at 2k by 1k pixels. This means they'll only be installed in smaller theatres, because such low resolution looks really bad on larger screens. Also, the compression isn't lossless, like the
F-G will be showing off these projectors this year at CeBit, according to marketing bumpf I got from them recently. This BBC story is probably based on a press release from the building tsunami of announcements leading up to CeBit.
the AC
Hemos is like...sci-fi fans;he thinks technology is cool, but he hasn't bothered to understand the science it's based on