Generic data object. Unites form and essense aspects represented by Content and Source. Used to aggreate properties that may be extracted from both content and source.
Content fingerprint: a small ID calculated from content byte stream, aimed at uniquely identifying the content. Abstract.
Is some portion of content encrypted? Setting this field doesn't imply that all data is encrypted.
Content/data size in bytes. See also storageSize
Content contributor. Secondary contributor.
Links to the original content from which this content is derived
Software used to generate the content byte stream
Format subtype. Use to indicate format extensions/specifics
Content subject. The shortest possible description of content
Content title. Description of content an order of magnitude more elaborate than Subject
Content description. Description of content an order of magnitude more elaborate than Title
Content summary. Description of content an order of magnitude more elaborate than Description
Content plain-text representation for indexing purposes
Generic annotation. Annotation provides a set of document description properties(like subject, title, description) for a list of objects it links to. It can link to other annotations, however interpretation of this may differ between specific annotation classes..
Generic folder. In general, folders represent a tree-like structure(taxonomy), however on occasion this rule may violated in cases like symlinks.
Generic media content list(playlist). Linking to other content types is forbidden
Generic audio list(playlist). Linking to other content types is forbidden
Tag/keyword. As opposed to folders, there are no limitations on the structure of tags and arbitrary overlaps are possible.
Bookmark. Currently there's nothing that would distinguish bookmarks and tags
Revision-controlled repository. In case of distributed repositories, those must be linked with derivation relations.
Message communication channel like chatroom name or mailing list
Personal email message(not related to a mailing list or discussion group)
Email message addressed at/received from a mailing list
Email message addressed at/received from a news group
Defines a textual aspect of content. Properties represent only actual content intended for the user, not markup. Other parts of content like markup should be described using other clsses. Abstract class.
Text content which doesn't fit any other text-based classes. Corresponds to Tracker's Text category.
Document is an arrangement of various atomic data types with text being the primary data type.
Document category: book, article, flyer, pamphlet whatever
Document page count. Slide count for presentations
Documentation is a document containing help, manuals, guides.
Text document. For word processing apps.
Generic raster/sampled media is considered consisting of Sets of Samples being reproduced(played/shown) at once. We describe: sample data type(int/float), data bit depth,configuration(color space for images, channel count for audio); set configuration(pixel dimensions for image); set count and rate.
Media sample data bit depth: 8, 16, 24, 32 etc
Media sample configuration/arrangement of components
Media set rate. Sample rate for audio(set=one sample per channel), FPS for video
Media set count. Sample count for audio(set=one sample per channel), frame count for video
The desired level of quality loss of lossy compression
Media codec type: lossless, CBR, ABR, VBR
Visual content color space(RGB, CMYK etc)
Defines audio aspect of content. The content itself may have other aspects.
FOAF:knows relation. Points to a contact known by this contact.
Filesystem differs from other containers in that it has total/free/occupied space(though DBs too have similar properties), has volume(content.title), UUID for *ix(content.ID), mount point(if mounted)
File system total usable space, unlike size, which is the byte size of the entire filesystem including overhead.
Local revision number. An automatically generated ID that is changed everytime the generator software/revisioning system deems the content has changed.
Origin URL, e.g. where the file had been downloaded from
Actual space occupied by the object in the source storage. e.g. compressed file size in archive
Rating of the object provided automatically by software, inferred from user behavior or other indirect indicators.
When the content was used for the first time
When the content was last used. Different from last access as this only accounts usage by the user e.g. playing a song as opposed to apps scanning the HD
How many times the content was used. Only usage by the user(not general software access) counts.
Generic block device. Typically contains partitions/filesystems
Generic offline media. e.g. USB drive not attached at this moment.
Name of block device seen to contain the Content when it was online.
Generic system resource like man documentation
Last time the resource info was refreshed
File managed by a revision control system
RevisionID on which a revision-controlled file is based
Time of the last change to the base file in the repository(preceding the baseRevisionID?)
Who made the last change to the base file in the repository(preceding the baseRevisionID?)
The diff of the content and the base file
If true, the file has a merge conflict(can't be cleanly merged into the repository)
Generic embedded/inlined object: attachment, inlined SVG, script etc.
Email attachment encoding(base64,utf-7, etc)
Compression algorithm for archivers which support several
Level of compression. How much effort was spent towards achieving maximal compression ratio.