The Non-Graded Archival Master (NAM) is a fully texted image sequence of the non-color graded, fully conformed and locked picture, including final VFX, rendered in a single scene-referred color space with no output or display transform applied. The archival resolution will be specific to the project and will be communicated by Netflix. At minimum, the archival resolution will be no less than 3840x2160 (UHD) and must include the final delivery Active Picture area with no cropping, matting or masking applied over the image. If your primary capture format was less than 3840x2160 (UHD) please reach out to your Post Production Management or Creative Technologies Workflow contacts at Netflix to discuss your best options.
The file format of the Non-Graded Archival Master (NAM) will depend on the transfer function of the scene-referred color space as well as the bit-depth of the source files:
*ACES projects must be Linear / AP0, per SMPTE ST 2065-1. ACEScct encoded files will not be accepted.
**10-bit DPX (.dpx) will be accepted only if 50% or greater of the primary capture footage was 10-bit or lower.
- Frame numbering must be continuous within each delivered asset and must always be consistent across all picture archival assets.
- For feature films working in reels the frame number must be continuous within each reel. The initial frame number for each reel/segment is at the discretion of the finishing partner.
- Textless inserts must be delivered with image properties identical to the corresponding texted asset.
- Textless inserts must include a textless background for any shot/sequence of the content that contains on-screen graphic text.
- Textless inserts must be provided cut-to-cut (i.e., the textless insert should not begin or end in the middle of a shot, the entire shot should be provided).
- Textless main titles or credits do not require a distinct naming convention from other textless inserts.
- Textless inserts must be numbered to match the numbering of the corresponding texted shot/sequence.
- If the content includes a significant amount of on-screen graphic text throughout, it is acceptable to create full-length textless asset rather than providing segmented frame ranges.
- In the context of this document, graphics overlays such as emojis or text balloons should be considered texted elements.
Quicktime Wrapped Non-Graded Archival Master Exceptions
- Quicktime wrapped compressed formats may be acceptable under limited circumstances, particularly in Animation workflows where source media is entirely compressed. Please consult Netflix to determine if QuickTime delivery is acceptable for your project.
- Minimum acceptable compressed formats:
- HDR: 12-bit, DNxHR 444 or ProRes 4444 XQ
- SDR: 10-bit, DNxHR 444, or ProRes 444
The purpose of a NAM is to preserve the final picture of a title in a high quality agnostic format limited only by the original source in order to allow for a lossless starting point in generating future derivative masters. These best practices should serve as a guide to help in meeting the Specifications above while addressing most common edge case scenarios.
- It is acceptable for a Non-Graded Archival Master to contain color bars, framing charts, head/tail black, head/tail visible pop for sync, or Academy leaders if any of these are present in the timeline the asset is generated from, however all non-color grade related content from the first-frame-of-action (FFOA) to the last-frame-of-action (LFOA) must match the final/approved IMF.
- If a non-color grade related change in picture is made to the IMF during the process of delivery (such as updated VFX, clean up, graphics or optical work), then the Non-Graded Archival Master asset must be updated to contain that same change
- During the DI process, working in a Color Managed framework can help ensure that the NAM is delivered in a single scene-referred color space and avoid any colorspace or transfer function mismatches within the asset, as illustrated below:
- For more information on Color Management, refer to the Image + Color Workflows section.
*as viewed on a display without the proper mapping applied
FRAMING & RESOLUTION
- While NAM must have at a minimum an equivalency to the Streaming Master (IMF)’s Active Picture, more often than not the NAM will be larger than the IMF since it should include any extra captured area, which is often cropped and/or hidden by Active Picture area blanking in the IMF. The Active Picture area is determined by the delivered framing chart.
- Global up-scaling to UHD should not be employed and will result in an invalid NAM.
Examples of Optical Effects: stabilizations, reframing, removal of production equipment, cosmetic fixes, etc.
- Any effect or fix applied in the online editorial process should be included in the Non-Graded Archival Master (NAM).
- Any effect or fix applied with a color grading process should be excluded from the Non-Graded Archival Master (NAM).
- In the case of reframing, a NAM is valid as long as the image represented in the Archival Master's Active Picture area matches the image available in the streaming master (IMF)'s Active Picture area.
ASSET REVIEW AND CONFIRMATION
Post Vendors often have access to all relevant assets used to create a NAM, from Camera Original Files all the way to the IMF, and therefore are usually best suited to conduct the Asset Review. In the Asset Review the NAM is compared and contrasted against the IMF to confirm that the NAM contains the fully conformed and locked picture, including final VFX. It is also recommended a verification against the Original Camera Files for a color check to confirm that the NAM is rendered in a single scene-referred color space with no output or display transform applied.
After the Asset Review takes place a Checksum Manifest should be generated. The manifest will then be verified by Netflix confirming that no content has been lost or altered during the delivery process. Checksum Manifests should be provided in one of the supported formats:
- Media Hash List (MHL) at the root level of the folder being delivered. The MHL should include entries for all files in the delivered folder. MHL manifests can be generated by a large number of 3rd party or open source tools.
- Checksum.txt in the folder containing the image sequence. Checksum.txt manifests can be generated by Content Hub Command Line (chcli) tools.
Please note that “zipping” of NAMs is no longer required and should not be done.
If you have any questions about Asset Review or Confirmation, please reach out to your Post Production Management or Creative Technologies Workflow contacts at Netflix.
FOLDER STRUCTURE & NAMING CONVENTION
Details on folder structure and file naming for delivery can be found at ‘Picture Archival Assets: Folder Structure and File Naming Convention’.
Added "Additional Resources" link for "ACES Deliveries in DaVinci Resolve."
Updated language around Best Practices for clarification of the language and adding further examples.
Consolidated Best Practices into this article, adding the "Asset Review and Confirmation" item to that section.
Updated language around Quicktime Wrapped Non-Graded Archival Master Exceptions to specify that these are the minimum requirements and also to specify different codecs for SDR and HDR.