Intern:Binary object

Binary (large) objects (BLOB) are digital files consisting of plain text, photos, grafics, films, sound or binary data in specific formats. BLOB are stored in a file system on a hard disc/tape robot combination (hs=hirachical storage). The metadata are stored in the relational database with a link to the BLOB.

BLOBs are archived in two steps:

(1) Metadata

Provide list of events (station/site/profile), describing the location of the BLOB. Mandatory are the fields LabelEvent (must be unique), LatitudeEvent, LongitudeEvent; recommended are ElevationEvent, DateEvent, TimeEvent, Gear; (for profiles, all fields can be given twice for start and end point); optional fields are Remarks and OptionalLabel. - In case the stations were operated during a campaign (cruise/expedition), information about its name (code/label), time, basis/ship, responsible scientist, and citation of report should be given.

(2) Data

BLOB are archived in at least one standard exchange format (jpg, gif, tiff, png, pdf, txt, shape, segy, wave, ...). Proprietary formats shoud follow international standards as far as defined. Data are archived with one data description per event. Required description fields are: Data set title, principle investigator (PI), method, comment, and reference(s) if published. A more detailed description of a dataset can be added as a pdf-file.

There are two ways of georeferencing a BLOB:

a) The event is a station with one (two) pair of latitude/longitude -> all BLOB will be added to this event, equivalent to one pair of lat/long.

b) The event is a profile described in detail by several pairs of lat/long, giving each BLOB its own georeference; -> in this case a list must be provided, containing the mandatory columns


 * Event label
 * date/time
 * latitude
 * longitude, both in decimal degree
 * filename of the BLOB
 * further columns with analytical and/or technical data may be added as required.

Due to the automated import of BLOB, filenames should follow a certain syntax: EventLabel_describer.extension The describer can be used individually and may contain a code (date/time, ordinal number, depth, length, ...) or the type of a BLOB (photo, x-ray, description, video, ...) or a combination of both. (Do not use spaces or special characters in filenames).

Examples for filenames of BLOB (example):


 * Photo EventLabel_photo.jpg
 * Photo of a segment EventLabel_begin-end_photo.jpg (GeoB1234-5_678-778_photo.jpg)
 * Photo, x-ray EventLabel_x-ray.tiff (GIK12345-6_000-100_x-ray.jpg)
 * Photo w time EventLabel_hh_mm_ss.png
 * Photo w date/time EventLabel_yyyy-mm-ddThh_mm_ss.jpg
 * Photo w ordinal number EventLabel_0034.png
 * Grafic of a segment EventLabel_begin-end.gif
 * Description as pdf EventLabel_begin-end_descr.pdf (GeoB1234-5_678-778_descr.pdf)
 * Plain text EventLabel_comment.txt (PS58/012-5_agecontrol.txt)
 * Film/sound sequence EventLabel_begin-end_video.avi

In case several events occured at one site (e.g. box corer followed by a piston corer), one directory, named after the site, should contain the documentation BLOBs of all events. This will allow a synoptic overview of the availability of all photos and graphics from the same site; however a data set description must be defined for each event (in this case all pointing to the same folder).

Examples of data sets linked to BLOB:

a) dataset consists of graphics and photos as a documentation of a geological sediment core. In the header the fields of the metainformation as described above are listed. In HTML-view the grafic objects are shown as thumbnails, a click on a thumbnail starts download of the file in full resolution.

shows photos from the ocean floor along a transect. Due to a missing relation between photo and precise position, all photos are related to a single pair of latitude/longitude only; in addition the lat/longs describing the track are given in one minute time resolution as additional text file. For a convenient download of all photos an extra link is added.

b) is a fully georeferenced data set containg the description of a cruise track with links to BLOB as seismic and grafic files from certain segments of the track. Columns with further technical data are added. The URL shows the path to the mass storage system for BLOB used by PANGAEA.