A digital cinema package is the standard delivery format for film screenings at a digital cinema. Most major movie theatres today are digital cinemas. That means any sort of digital projection, be it a short or feature film, requires a digital cinema package or DCP for short.
DCPs play on expensive digital projectors. And for the most part, digital cinema packages have replaced the 35mm film reels used for years by theatres. The good news is, that producing DCPs costs significantly less than it does cranking out 35mm prints.
So let’s break down what is a digital cinema package, how to create a DCP, and the best way to deliver it to a theatre.
What is a Digital Cinema Package?
DCPs are audio, video, and metadata files (e.g. subtitles) configured for cinema servers. These servers connect to the digital projectors we mentioned earlier. Every single frame of a film is a separate folder within the DCP. A typical DCP includes XML files for metadata and MXF (Material Exchange Format) files. MXF is a video file container that wraps the track files according to Society of Motion Picture and Television Engineers (SMPTE) standards.
The video track is encoded frame-by-frame in JPEG-2000. This is a lossless compression codec mastered at 24 frames-per-second (FPS), with high-resolution picture quality. The audio file is a 24-bit linear PCM uncompressed multichannel WAV file.
Most DCPs have a bitrate of around 250 Mbps. The majority of digital projectors at theatres can’t handle anything higher. Digital cinema servers run on Linux operating systems, which means DCP hard drives are formatted in Linux EXT3.
Because DCPs are usually encrypted, a Key Delivery Message (KDM) is required to ingest and play the content. You can think of a KDM as a content encryption key. KDMs specify when, where, and how that version of the film can be played.
A digital cinema package can be around 200 GBs in size or larger. The DCP for Spider Man: No Way Home is around 500 GB and includes the 3D and 4K versions of the 2h 28m-long film).
What about physical DCPs on hard drives?
For years the standard delivery of films to movie theatres was through a physical DCP. Some cinemas and film festivals still use physical DCPs but a majority of commercial releases are delivered via satellite or ‘terrestrial’ (IP-based) methods.
A physical DCP is a secure packing crate consisting of a heavy-duty case containing a hard drive, a power brick, and any cables required for ingestion.
Most physical DCPs are shipped in CRU drive enclosures. These are semi-indestructible DX115 hard drive carriages originally designed for military use. The Inter-Society Digital Cinema Forum (ISDCF) notes that the use of USB-3 portable hard drives has become common.
What are the Advantages of a Digital Cinema Package?
The main advantage of a DCP is that it’s really the only way to get your content played on digital projectors around the world.
1. DCPs are secure
You can make a million copies of a DCP, he explains, but if you don’t have the KDM configured for your equipment, you can’t play them. KDM’s also specify the date and time a DCP can be played. This has led to some…embarrassing incidents at film festivals.
2. DCPs are easily updated
Because DCPs are a package of files (and not one big file), they can be edited without having to update the entire production. One master file can be localized for dozens of regions. For example, by adding dub tracks or subtitles as small pieces of metadata.
3. DCPs are verifiable
As soon as a DCP gets copied onto a cinema server, a SHA265 checksum validation automatically runs to verify the content “is in the same state as it left the lab,” he says. This ensures no unauthorized modifications have occurred.
What Does it Cost to Make a DCP?
You can expect to spend around $1000 USD for a single DCP from a professional shop. But, there are caveats based on resolution, length of film, and turnaround time.
Most DCP houses price by minute of footage. Around $10-$15 per minute. If you need a fast turnaround or a DCP for a 4K or 3D film, it will add to the hourly rate. Most DCP houses also offer quality control on special monitors calibrated for screenings. This is factored into the price as well.
DCP Maker now offers DCP creation starting at $1 per 1 minute.
How do Cinemas Use a Digital Cinema Package?
Physical DCPs are delivered to cinema managers/operators the old-fashioned way: by ground courier.
Once received, physical DCPs are connected via USB or eSATA to the cinema’s theatre management system (TMS) or playback server for ingestion.
Individual cinemas are then responsible for shipping physical DCPs back to distributors. The hard drives are then reused for the next batch of DCPs. You’ll often find those hard drives have multiple stickers on them from past DCP releases.
Satellite and IP-based DCP delivery
The potential for damage is why cinemas now receive DCPs via satellite or over the internet. Along with cost and convenience. According to the ISDCF, several present-day DCP delivery methods exist. This includes satellite, internet, and site-to-site file sharing via a secure network.
The Digital Cinema Distribution Coalition (DCDC)—an initiative by industry heavyweights such as Warner Bros. and AMC Theatres—handles digital distribution for the vast majority of major studio releases.