Administrator's Guide - Audio Digitization
Members of the Digitizers group digitize audio, create encoded derivative files, generate metadata, and load it into Variations. To turn on the Digitizer interface (if authorized to do so) set the property dml.login.digitizerMode to true in the client's dml.conf. The filenaming scheme used by Variations can be configured in dmlserver.xml.
Here are the specifications for audio digitization used at Indiana University for items being put into Variations:
- File should represent a full CD or Side (in the case of LPs or tapes), not tracks
- Save as type: Wave (Microsoft) (*.wav)
- Format: PCM
- Attributes: 44,100 Hz, 16-bit, Stereo
- Regions List: (Do not save Regions or Markers)
- Save Summary Information in file: Not checked
Audio files can be digitized using the workflow listed below or other tools like Quicktime PRO can be used. If the workflow below is used, the clients used by digitizers will need to have the dml.digitizer.useMP4 property set to true. This changes the default file format and compression set in the MediaObject metadata.
There are three options for server processing of incoming audio: minimal, mp4 processing, and none. Minimal audio processing will copy the files from the incoming directory to where Variations can use them and update necessary metadata. This approach requires the derivative files placed in the incoming directory to already be streamable by the Darwin Streaming Server. Mp4 processing will extract the first audio track from an mp4 or mov file and reconstruct an mp4 file that is hinted and useable by Darwin. This mode must be used if the MP4 Encoder described below is used. Enabling mp4 processing requires the mp4Processing attribute be set to true in dmlserver.xml. If the AudioProcessing tag is not present, then no processing will be done by the server (this approach is not supported for test sites). outputDir, an optional attribute, is the path to the directory where Variations will place the deliverable files. If an output directory is not specified, Variations will determine this location by looking at the filesystem usage statistics for each LeaseManager's ContentDir of a LeaseResource that matches the contentType "audio".
The filename scheme used by Variations is specified through the FilenameScheme tag in dmlserver.xml. See Filenaming Schemes for more information on possible settings.
More information about the standalone GUI encoder that uses Nero's Digital Audio MP4 encoder can be found here.
An overview of the entire digitization process can be found here