Digital File Types
Digital file types describe the types and characteristics of the files produced from the digitization of original record materials at the National Archives and Records Administration (NARA), as well as the standard or most common data formats that the Digitization Services Branch uses to store digitized records.
Audio File
An audio recording produced from original analog or digital audio formats that has been encoded using Linear Pulse Code Modulation (PCM). Sampling frequency, bit-depth, and monophonic or stereo, for example, are important characteristics of audio files.
WAV (Waveform):
The Sustainability of Digital Formats site at the Library of Congress contains information about the WAV file format.
NARA's WAV files are identified as PUID fmt/141 and fmt/142 in the PRONOM database.
Although WAVE is the formal full name of the file format (Waveform Audio File Format), the three character file name extension is WAV. We have used the three character file name here in keeping with the way the file format is most often expressed as a file name extension.
This file type is created for the following products:
- Audio Maximum Capture [AUD-P1]
- Audio Born Digital Original [AUD-P2]
- Audio Born Digital Transcode [AUD-P3]
- Audio Reproduction Master [AUD-R1]
- Motion Picture Film Maximum Capture - Soundtrack Audio Data WAV [MPD-P6]
- Motion Picture Film Reproduction Master - Soundtrack Audio Data WAV [MPD-R6]
MP3:
The Sustainability of Digital Formats site at the Library of Congress contains information about the MP3 file format.
NARA's MP3 files are identified as PUID fmt/134 in the PRONOM database.
This file type is created for the following products:
Video File
A video file is a moving image recording with synced audio (when applicable) produced from either original analog or digital video formats. Resolution, frame rate, aspect ratio, bit rate, scan type, field order, color space, and standard or high definition, for example, are important characteristics of video files.
AVI: Audio Video Interleaved
The Sustainability of Digital Formats site at the Library of Congress contains information about the AVI file format.
NARA's AVI files are identified as PUID fmt/5 in the PRONOM database.
This file type is created for the following products:
- Video Maximum Manual Capture - SD [VID-P1]
- Video Maximum Automated Capture - SD [VID-P2]
- Video Maximum Manual Capture - HD [VID-P3]
- Video Born Digital Original - SD & HD [VID-P4]
- Motion Picture Film Reproduction Master - HD AVI [MPD-R2]
WMV: Windows Media File
The Sustainability of Digital Formats site at the Library of Congress contains information about the WMV file format.
NARA's WMV files are identified as PUID fmt/133 in the PRONOM database.
No longer created, these are legacy files that may be found in the National Archives Catalog.
MPEG-2, 4:2:2 Profile Format
The Sustainability of Digital Formats site at the Library of Congress contains information about the MPEG-2, 4:2:2 Profile Format.
This MPEG-2 file is identified as PUID x-fmt/385 and x-fmt/386 in the PRONOM database.
This file type is created for the following products:
MP4:
The Sustainability of Digital Formats site at the Library of Congress contains information about the MPEG-4 File Format.
This MP4 file is identified as PUID x-fmt/385 and fmt/199 in the PRONOM database.
This file type is created for the following products:
- Video Online Delivery - SD MP4 [VID-D1]
- Video Online Delivery - HD MP4 [VID-D2]
- Motion Picture Film Reproduction Master Derivative - HD MP4 [MPD-R3]
- Motion Picture Film Reference Delivery HD MP4 [MPD-D1]
- Motion Picture Film HD MP4 (Custom Bitrate) [MPD-D4]
- Motion Picture Film HD MP4 for Streaming Service Upload [MPD-D7]
MOV:
The Sustainability of Digital Formats site at the Library of Congress contains information about the QuickTime File Format (MOV), as well as the Apple ProRes 4444 Codec Family.
This MOV file is identified as PUID x-fmt/384 and fmt/797 in the PRONOM database.
This file type is created for the following products:
Motion Picture File
A motion picture file is a high-resolution moving image recording, often with synced audio, produced from either original physical or digital formats. Bit-depth, resolution, frame rate per second, and color encoding, for example, are important characteristics of motion picture files.
DPX: Digital Moving-Picture Exchange
The DPX file format, or Digital Moving-Picture Exchange, is a pixel-based (raster) image format in which each content frame is a separate data file linked by metadata to play in the correct sequence.
DPX is defined by Society of Motion Picture and Television Engineers (SMPTE) 268M-1994, ANSI /SMPTE 268M-2003, SMPTE ST 268-1:2014, and/or SMPTE ST 268-2:2018.
The Sustainability of Digital Formats site at the Library of Congress contains information about the DPX file format.
NARA's DPX files are identified as PUID fmt/193 in the PRONOM database.
This file type is created for the following products:
- Motion Picture Film Maximum Capture - 4K DPX [MPD-P1]
- Motion Picture Film Maximum Capture - 2K DPX [MPD-P2]
- Motion Picture Film Reproduction Master DPX Capture for Exhibition [MPD-R7]
- Motion Picture Film Restoration Master DPX [MPD-R8]
DCP: Digital Cinema Package
A DCP or Digital Cinema Package is a collection of digital files used to store and convey digital cinema audio, image and data streams. DCPs typically contain JPEG2000 and Linear Pulse Code Modulation (PCM) wrapped in Material Exchange Format (MXF).
The Sustainability of Digital Formats site at the Library of Congress contains information about the Digital Cinema Package.
This file type is created for the following products: