Motion Picture Film Reproduction Master - HD AVI [MPD-R2]
Record Type: Digital Output from Motion Picture Film Source
Expected Use: Reproduction Master
Product Name: Motion Picture Film Reproduction Master - HD AVI [MPD-R2]
Product Purpose: The purpose of this product is to respond to reference and reproduction requests. The product is retained to act as a source for compressed reproduction/distribution master HD files, compressed HD and SD distribution files, and 2K DCPs.
Nature of Source Material: All 35mm and 16mm film elements (B&W or color) with or without sound in stable condition as demonstrated by a determination of “Medium” or below on the At Risk Assessment Guide.
Possible File Derivatives: This product can be used to make compressed reproduction/distribution master HD files, compressed HD and SD distribution files, and 2K DCPs.
- In some cases, this product may be a derivative file created from 4K or 2K DPX and WAV file sources.
- One-light color timing will be employed as appropriate during the initial capture process but otherwise, the files are unaltered.
- Due to hardware limitations at the time they were created, many existing NARA HD AVIs were encoded using the 8 bit YUY2 codec. These file sizes are typically ~6 GB/minute or ~360 GB/hour.
AVI (Audio Video Interleaved)
Target Total Bitrate: ~1000 Mbps for 10 bit
Typical file size: ~7.9 GB/minute or ~479 GB/hour
Quality Assurance and Quality Control for HD AVI Format Products
NARA uses a commercially available, automated batch processing software tool to evaluate specific quality metrics. Below is an outline of our current processes for HD AVI formatted products. We continue to adjust our benchmarks and workflows as needed. In addition, brief visual QC is performed to detect artifacts introduced during capture that require more sensitivity than automated systems provide.
NARA implements scheduled service and calibration protocols according to manufacturer recommendations as well as on an "as needed" basis.
The AVI filename contains metadata that associates the file with external sources of descriptive and technical metadata. Each filename is a unique identifier composed of the item’s record group, series, item number, reel number, source element designation, and bit depth (ex. 255-hq-199-r2_p_8bit.avi).
Item Level Evaluation: Automated Quality Analysis
Test plans are developed on a format/workflow basis in our automated QC tool. The test plan allows for some characteristics to be evaluated on an actionable basis (warning, fail, or pass depending on the defined parameters). Others are logged for internal use but are not actionable as a warning, pass or fail. Aim points for these benchmarks are evaluated against NARA's product specifications. The following represents the quality test plan technical characteristics for AVI products captured from motion picture film.
Container technical characteristics checked or logged include:
Video technical characteristics checked or logged include:
Audio technical characteristics checked or logged include:
The NARA Motion Picture Preservation Lab uses checksum verification for file transfers and for files in long-term storage
Reproduction masters are at a high enough quality that they may be used in a production context.
Currently, the Motion Picture Preservation Lab creates uncompressed video streams in an AVI (Audio Video Interleaved) wrapper as an HD reproduction master product option. Film scans are one-light graded and captured in the HD standard ITU-R Recommendation BT.709 color space, with adjustments made to ensure capture of the most possible image information.
The choice of a wrapper was one that NARA staff looked at very critically. According to an in-house international survey conducted in the spring of 2010 of over 50 institutions involved with film and video reformatting, the three main choices for preservation products were AVI, QuickTime (.MOV) or MXF (Material Exchange Format). Each has pros and cons. Based on the feedback we received, NARA has decided to use the AVI wrapper for motion picture reproduction masters for a variety of reasons, including:
- AVI is a stable open format with wide adoption.
- AVI files are playable in a wide variety of open source tools, including VLC.
- AVI is the NARA preservation master format for digital moving images from Video sources. Using the same format for reproduction masters from motion picture film sources allows use of the same hardware and software across the Moving Image and Sound Preservation Labs.