Bid adieu to the beautifully impure theatre experience. Say goodbye to the first day grains, and the end-of-the-week dust and scratches. The randomness of analog cinema reels daubed with imperfections is giving way to its digital successor; well, just like everything else did.
The evolution of cinematic formats began with the tin box holding the precious first-day-first-show film reel being replaced with a hard disk. But the hard disk wasn’t good enough an idea for some. Why replace one physical object with another? Why not digitize it and upload it to a server. The central server which is connected to a thousand others in different distant places with the A - Z of weather conditions. The individual servers connected to the highest-end digital projectors displaying cinema at its visual peak—no dust and scratches, no grains, just perfectly balanced colors which are saturated to perfectly please the human eye. This is the beginning of an era and it’s bound to affect and impact each one of us with its sheer quality.
UFO Digital Cinema
CHIP met the Indian pioneers of digital cinema who are not just providing digital cinema infrastructure to 1000 theatres across India but also accelerating the development of this technology by riding on the MPEG-4 platform. Simply put, the alternative MPEG-2 compression platform which is used to digitize movies requires 10 times the storage space as compared to MPEG-4. This means that it is not close to feasible to upload the MPEG-2 compressed file of a movie on to a server which would then be downloaded by the individual theatres. Which is why, the MPEG-2 compressed files are transported on a hard disk to theatres but an MPEG-4 file can be easily uploaded. This complete platform of uploading/downloading movies instead of physical transportation has a lot of benefits in terms of financial feasibility and more importantly, on the security front. We will dive into a little more detail of how this extremely complicated technology with the simplest interface works.
Reel to Screen
The responsibilities of a company like UFO Digital Cinema is dependent on the requirements of the movie producer. In any case, they have the entire infrastructure to provide an end-to-end digital cinema solution. Let’s understand the chronology of processes after the final edit of the movie is complete.
D5 Tape or .DPX files?: A movie is usually shot on a film camera, or in recent cases, a digital camera which supports resolutions as large as 2K. Film is converted into a digital format with a process called telecine. Telecine output is digital which is electronically recorded on a D5 tape. This is one output option which the digital distributor (for instance, UFO Digital Cinema) receives. This tape is then recorded on to their system using a D5 tape player. The system converts the recording into a set of frames and from this point the file compressing begins.
In some cases, production houses carry out a telecine process, apply color correction and then make a print which is called DI (Digital Intermediate). Because of this digitization process, the output files are in a digital format named .DPX (Digital Picture Exchange).
So, the D5 tape or the .DPX files are the two options of formats that the digital distributor receives.
The Capture Room: The digital distributor records the D5 tape data by playing it on a D5 player and grabbing it with a high-end capture card. In case of .DPX files, there are dedicated machines in their capture rooms to process this format. These high-end machines usually use an Autodesk software called Smoke.
Color Correction: This process is mandatory irrespective of the incoming format. Even though, the DI process—which may have happened before coming to the digital distributor—takes care of the movie’s color correction, the in-house process of correcting colors is specifically to is to target it for the final digital display medium. UFO uses Smoke in their color correction lab.
The raw content comes in D5 or .DPX formats, which is then processed shot by shot, or frame by frame according to the visual data. As different films (Kodak, Fuji etc) vary from each other, colorists refer to a film’s LUT (Lookup Table) to linearize the film file—a projected file needs to be linearized or flattened. A film file is logarithmic which means that the colors between 0 and 255 appear in a logarithmic fashion—this needs to be linearized by referring to a LUT. Color corrections are in the form of layers which are applied and merged by rendering as one output file. After the color correction procedure is complete, the producer and his crew usually sign off the final print after watching it at the preview theatre
Encoding and encryption: The color correction procedure gives flawless quality to the movie file, and the next process in the digitization chain brings in watertight security. The output after color correction is encoded (compressed) using MPEG-4 at approximately 15-20 megabits. MPEG-4 helps keep the file size light and maintains top-notch quality (see box).
Frame by frame encryption is carried out after the encoding is complete. The encryption keys are then stored in a database making the whole pack extremely secure. These stored keys are used to create licenses later. These licenses are basically containers of the encrypted keys which is then itself encrypted in 24-bit.
Satellite uplink: The secure movie file is uploaded using a fibre optic direct link to UFO’s satellite partners. The servers located in theatres download the encrypted movie file and record them. A lot of the next steps between this stage and final exhibition happens outside the theatre—the business deals between producers and regional distributors, and between distributors and theatre exhibitors. Usually, the digital distributors upload the movie by Wednesday or Thursday on to the central server which is then downloaded to the theatres but the downloaded file is still encrypted.
The distributor informs the digital distributors to issue licenses which is also in the form electronic messages. These posted messages then come in and tell the database to produce licenses from the encrypted keys. This makes it a secure transaction again because there is no human intervention. The encryption keys are then transmitted through the satellite or through a back channel (which is connected to each and every system in the field), which is connected back to the center through CDMA phones or other modes. The back channel is important because it allows us to extract playback logs which tells us how many shows were played and where. The playback logs can be reconciled with the release orders by the distributors. This gives the distributor, theatre owner’s detailed information about shows consolidating the business transaction end. Along with all the technical work, UFO also becomes the network operation center.
At the moment, UFO has acquired close to 1000 cinemas all across the country to whom they have also distributed the infrastructure. From their central server location, they can do much more than mentioned earlier. In case, if any problem arises in any of their theatres, they can remotely diagnose the problem and repair it almost instantaneously.
This way, a digital distributor like UFO becomes the hub between the producer, distributor and exhibitor and the whole service is provided as a package. There are also other benefits like invisible watermarks which help trace down a pirate from a pirated copy down to the show, date, and location details.
Complex Infrastructure with a Simple Face
There were a lot of other struggles which stood in the way but were conquered and today this technology and protocols have become an existing benchmark in India.
To exemplify: a majority of the 1000 theatres which UFO manages in the country are distributed across extremely different regions. Some theatres have completely computer illiterate employees who are operating the projectors conveniently—the same person who may have never touched a mouse in his life is now downloading via satellite, taking licenses, browsing the content, scheduling the shows! This has been made possible because of the absolutely humble stop/play/rewind interface of the technology at the user’s end.
Even the advertising and trailer models in this business have been embedded in the technology by ways of parking pre-show content on the server and sending a playlist to the theatre. The server looks for any pre-show information and simply plays that before the movie!
There is also a system in place to maintain a synch (using a constant pulse) between the central server and each of the other servers which are communicating on a minute-by-minute basis and at any time, if the synch is lost the central server reconciles the time on the remote server immediately. Even, the servers have been tested in extreme conditions to simulate the possible scenarios in some theatres and they have successfully endured an extreme range of 0 - 55 degree Celsius range!