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datenwolf214 karma

There are two key components: A so called "Digital Cinema Server", and the "Digital Cinema Projector". Inside the projector there's the so called "Media Key Block" and the "Light Engine".

The server is basically just a large storage system with HD-SDI interfaces, that feeds the still encrypted video stream to the projector, where the signal gets decrypted with a key, that has been formerly submitted from the studio. Keys are exchanged via RSA2048, the content is encrypted using AES128. Audio is usually decrypted and outputted by the digital cinema server, but sometimes by an additional part from the projector.

Video is encoded as single JPEG2000 frames, 12 bits per channel, XYZ color space with a gamma of 2.6. Audio is PCM 24 bits/sample, either 48kHz or 96kHz sample rate. Up to 16 channels can be encoded, but so far only 8 are defined.

The servers can be connected to the so called "matrix" with is a standard automation system for cinemas, also controlling the lights, curtain, screen croppers, etc.

datenwolf154 karma

After having worked together with a number of PhD students from China my worries dimnished. During my Diploma/M.Sc. thesis I dreaded every experiment I had to do together with them. For one single reason: They were very good at doing what they memorized in their formal education. But whenever a task required some creativity this was a huge roadblock for them. It never occoured to them to tinker some AC terminator to clamp the reflections on the trigger lines, or to solder a few wires to a IC in midair to fix a problem.

The Chinese way of education excels at producing a lot of high tech factory workers. It allows them to quickly reproduce existing technology and also make improvements to it. But if western education systems are good at suppressing creativity, then the Chinese education system it seems has brought killing creativity to perfection.

datenwolf95 karma

Well, you can make a copy with ease, no problem there. The problem is playing it. For this you need the aforementioned, so called essence key, which is AES128. Key exchange is done by Diffie-Hellmann with RSA2048 and the keys are stored in the so called MKB on NVRAM, a dedicated device built into the projector itself. The MKB generates a asymmetric keypair. The public key goes to the studio, which encrypt the essence keys with it and send them by a KDM (Key Delivery Message) back to the MKB.

There's a bunch of switches, and should you open the projector or get near the MKB the NVRAM gets erased (think CMOS-Clear switch on your computer's mainboard). Also the MKB inserts a digital watermark of the used public key into the frames so that should a copy of the decoded signal go online, you get to know, which projector this signal came from.

datenwolf77 karma

BTW Science, how was working with your colleagues from SmarterEveryDay like?

datenwolf63 karma

Do you kinda know what everyone says (the science stuff) or does it go over your head like Jack?

Most of it is technobabble anyway. I devoured Eureka Season 1 and 2, but after that I somehow lost interest.

The problem for me was, that I'm actually a physicist, doing research at a particle accelerator. My key interests are lasers, particle detectors and ultrashort phenomena.

And unfortunately the longer Eureka run, the higher the probability got, that it would dabble into those areas I'm practically living in, like an unwelcome intruder of the planet of inaccuracy.

Hey, if SyFy needs some thorough science advisor, who also writes sci-fi short stories every now and then, tell them I'm open for that.