Final, theatre-ready file package — JPEG2000-compressed with timecode, metadata, OV and audio tracks. Loads directly onto cinema server.
Digital cinema playback only works with a standardized package structure — and this is precisely where the DCP comes into play. You don't simply put your finished edited and graded film into the cinema as ProRes or DNxHD, but rather create a completely separate, self-contained data package that the cinema server can play back without any fuss. The DCP is your final deliverable to the distributor and the cinema operators — it contains everything the projector needs: image, sound, subtitles, metadata, and a unique identifier.
Technically, this works as follows: The image is compressed in JPEG2000, a wavelet-based compression that is significantly more space-efficient at cinema resolution (typically 2K or 4K DCI) than other methods, without any visible loss in quality. The audio tracks are provided as uncompressed WAV or as Dolby/DTS compressed versions — depending on what the cinemas are to receive in the package. In addition, there are XML metadata containing length, timecode, frame rate, and format specifications. The critical point: everything runs in a strict folder structure — ASSETMAP, VOLINDEX, PACKINGLIST, and the individual RSA directories for video and audio. A deviating file structure, and the cinema server won't read anything.
On set or in post-production, you'll notice little of this format — your work ends with DCP creation in the lab or with the DCP service provider. But when it comes to delivery, it gets critical: every audio track must be correctly mapped, the timecode must match the edit, the frame rate must be exactly 24p or 25p. A wrong frame, and the entire synchronization will be messed up. Most distributors have very precise requirements — you often need multiple versions: one for Germany, one for Austria, possibly one without subtitle overlay (OV), and one with subtitles (OV with separate SUB track).
Practically, this means: allow for 1-3 business days for creation at the lab, factor in revisions (incorrect black levels in the image, audio levels too low), and store the final DCPs in at least two locations — one goes to the cinema, one remains as an archive. The file size is considerable — a 2K DCP with stereo sound quickly reaches 50-150 GB, 4K even more massive. USB hard drives are standard for transfers, but uploading via Aspera or FTP has also become common.