This option is used to output an MPEG-2 reproduction master to an authored DVD.

MPEG-2 with 29.97 fps

Container:

• VOB (Video Object files) for Video and Audio Data

Essence Data:

• MPEG-2
• Program Stream
• Main Profile Main Level
• Top field first

Video data:

• Video frame size: 720x480
• Video mode: CBR
• Video frame rate: 29.97
• Interlaced scan
• Single-pass encoding

Audio data:

• Audio channels: 2 (stereo L R)
• Audio bitrate: 256 Kbps
• Audio mode: CBR
• Audio codec: AC-3
• Audio sample rate: 48 KHz
• Audio sample size: 16 bits

Typical file size: 60 MB/minute or 3.6 GB/hour

None. Other distribution copies would be created from the higher quality reproduction master.

This is the current delivery mechanism for the Reference Rooms for all digital moving images.

Audio and video levels may be adjusted as appropriate during the initial capture process. Reproduction and distribution files may have additional image improvements such as minimal color correction if necessary.

The Digitization Services Branch’s Quality Assurance and Quality Control (QA/QA) program is evolving as new tools and resources are acquired and implemented. We are moving towards more automated and integrated systems to assure the products we make meet the specifications outlined. Digital products created by the Digitization Services Branch are validated against standardized format specifications and signature files when possible. We use a variety of format specific batch evaluation and validation tools both open source and vendor supplied, to assure technical quality level specifications are met. All files, but especially distribution system specific files, are inspected for successful playback in a variety of tools and environments. Additional quality control workflows are in development.

Equipment/System Evaluation
NARA implements scheduled service and calibration protocols according to manufacturer recommendations as well as on an "as needed" basis.

Metadata
Embedded metadata: NARA is working on embedded metadata guidelines for all file types.
Technical metadata: NARA is finalizing technical metadata schemas for all file types.

NARA is developing an in house job tracking order system to better coordinate work at the Branch level.

Item Level Evaluation: Automated File Characteristics Analysis
Fixity: NARA is evaluating workflows to create and validate checksums for each digital file.