The following is a guest post by Carl Fleischhauer, a Digital Initiatives Project Manager at the Library of Congress.
More often than not, the Federal Agencies Digitization Guidelines Initiative Working Groups (one for still images, one for audio-visual) find themselves walking a line between codifying widely adopted practices and exploring new ideas and new technologies that will extend or advance those practices.
In the realm of recorded sound, for example, one FADGI Audio-Visual Working Group guideline recommends modest refinements to the typical use of the header for the Broadcast WAVE file. (Strictly speaking, the recommendations pertain to the “broadcast extension” or “bext” chunk in the file, and the recommendations come with an open source tool to edit the data in the chunk.) At the same time, the Working Group’s audio work is exploring thorny issues associated with the metrics and methods required to measure the performance of audio Analog-to-Digital Converters. The goal is to permit modestly resourced archives to test their ADCs against FADGI’s 2012 performance guideline. This has turned out to be surprisingly challenging, and we will be publishing a progress report early next year.
Today’s post pertains to a FADGI report on the scanning of motion picture film. A draft version of this report was placed online in September, and it includes advice about practices that have been adopted in a number of archives as well as updates (and forecasts) on new developments that promise to change those practices. The three-part report combines (1) an introductory essay, (2) a set of tables that describe a range of film “inputs” and digital “outputs,” and (3) concludes with a model statement of work for the outsourced conversion of film to video.
In the words of the report, “The effort is intended to be an initial advisory for agencies that face increased requests for high quality file formats from moving image content, but are unaware of, or overwhelmed by, the plethora of file format choices available and the nuances of the technical specifications that ought to be considered.”
The report was produced by a FADGI subgroup led by Criss Kovac and Heidi Holmstrom from the National Archives and Records Administration, with active participation from the Library of Congress including the Packard Campus for Audio-Visual Conservation, the American Folklife Center, and the Office of Strategic Initiatives.[1]
Many other agencies also participated, including the Smithsonian Institution and the National Air and Space Administration. FADGI is currently seeking comments from the public on this draft through the end of 2015.
Film scanning is the subject of an ongoing debate within the film-archiving community, especially scanning in the name of preservation. The authors of this report respect the full range of ideas articulated in this debate, and they positioned the FADGI document in a careful way:
“It is worth saying that digitization itself is the subject of vigorous debate among film-preservation specialists, with many practitioners insisting that photochemical, film-to-film reproduction is the only acceptable method for preservation reformatting. (Many others disagree.) This FADGI description is interim and limited: the digitized copies we describe are intended to serve as surrogates, e.g., digital footage for a new television program or a production master suitable for use in the creation of a DVD or for streaming. The original film materials ought to be protected and retained.”
Current scanning practices are covered in the report’s middle section on film inputs and digital outputs and in the final section that presents the model statement of work. The input-output tables provide an overview of specifications for the conversion of motion picture film to two different types of outputs. The first is what is sometimes called the “scanned film” output, generally represented today by the DPX format.[2]
The second output is “video,” meaning the format family typically seen in television broadcasting (and, today, in many online spin-offs). The DPX option allows for higher resolution imagery (and yields bigger files) than the video option and, in the words of the report, “the DPX image+audio output is future-proofed to a greater degree than the video output.” This future-proofing, of course, makes DPX film scanning a stalking horse for those who see digitization as a preservation strategy. Meanwhile, the model statement of work uses film-to-video conversion as its illustrative example.
The report’s introductory essay sketches the context for film scanning, and highlights some indicators of the complexity of the field. One example is the extent of variation in motion picture typology. Archive holdings include “gauges ranging from 8mm to 16mm to 35mm and above; with types of footage ranging from camera original to pre-print or duplication materials to release prints, containing imagery in color and black-and-white, negative and positive; with many different aspect ratios (to say nothing of anamorphic, 3D imagery, and other variations), and with soundtracks of various formats and configurations.” Each historical format will require a specialized approach, and the authors confess that they selected “the easy ones” for this report: 35mm or 16mm positive, color or black and white, in the standard 4:3 aspect ratio, with a limited range of soundtrack formats.
The introduction also characterizes some of today’s developments that are taking the field in new directions. As it happens, these include the entertainment industry’s development of new formats intended to replace the current versions of DPX. The Science and Technology Council at the Academy of Motion Picture Arts and Sciences (the Oscar folks) and SMPTE standards committees are applying sophisticated image science to the development of new practices, formats, and standards that will provide improved support for film scanning in the future. Once widely implemented, the Academy “ACES” project will be especially important for color materials in memory institution archives.
Another new development, this one on the video side, is also sketched in the introduction. Technical leaders in broadcasting have started to promote what is called Ultra High Definition Television (UHDTV), with image resolution higher than that offered by today’s High Definition (HD) signal.
How might this affect our memory institution planning for the next-round of film digitization? The report offers this insight: “Higher-than-HD standards have come or are coming to theatrical, broadcast, and non-broadcast dissemination. The adoption of digital cinema and UHDTV will push producers toward higher levels of resolution and drive demand for film scanning at those levels.” The authors add, “Film scanning inhabits a realm where new, disruptive developments abound.”
FADGI seeks comments from the public on this draft, with a nominal due date of December 31, 2015.
[1] The several units that comprised OSI were dispersed in a recent realignment of the Library’s service units. One of the two OSI staff members who participated in the film-scanning project is now part of the Technical Policy group within the larger Library Services unit, while the other is part of the National Digital Initiatives group within the larger National and International Outreach unit.
[2] DPX is a standard from the Society of Motion Picture and Television Engineers: Standard for File Format for Digital Moving-Picture Exchange (DPX), SMPTE ST 268:2003 and Amd. 1:2012.