In general, archival standards expect imaging equipment set to yield images at 1:1 using optical resolution without resampling. Interpolation of spatial resolution to achieve higher ppi values shall not be permitted. Each object shall be digitized according to its type to the stated resolution appropriate for the material being scanned. The resolution requirement will be specified in pixels-per-inch (ppi) or dots-per-inch (dpi) and shall be achieved utilizing the optical resolution capabilities of the equipment employed to capture the image. The spatial resolution requirements are anticipated to range from 200 ppi to 5000 ppi dependent upon the source materials.
Each collection in Image Collections Online is assigned an identifier, referred to as a "VA number" (since the identifiers all begin with "VA"). VA numbers consist of VA + letter + four digits (e.g., VAC1234). Files are named starting with the VA number + hyphen + five digits, with the final five digits indicating the order in which the image was digitized/named (e.g., the first image scanned in a collection would be VAC1234-00001). For multi-page items, such as fronts and backs of photographs, the files are named using the regular file name + hyphen + two digits indicating the order of the individual pages in the item (e.g., the front of a scanned image would be VAC1234-00001-01 and the back of the image would be VAC1234-00001-02).
Delivering Scanned Files to DLP
Once a collection is set up to be included in Image Collections Online, a secure dropbox will be created into which the digitized images will be placed for ingestion. Ingestion typically occurs overnight, so files placed in the dropbox on one day are available for cataloging in Photocat the next day.
Within the dropbox, single images should be placed in the top level of the dropbox folder. Each multi-page item will need to be located in an appropriately-named folder within the collection folder of the dropbox. The folder should be the same name as the files – minus the pagination (e.g., files VAC1234-00001-01 and VAC1234-00001-02 will be placed in a folder named VAC1234-00001, while the single file named VAC1234-00002 will be placed directly in the top level of the dropbox folder). No other folder nesting is allowed.
Note that one dropbox is created for each unit, not for each collection, so if your unit has a dropbox created for one collection, future collections will use that dropbox as well. Filenames will differentiate between image files that belong in different collections.
The dropbox will be accessible through SFTP. If you do not already have an SFTP protocol client, the are available via IUWare (http://iuware.iu.edu/Windows#Details/785) WinSCP or PuTTY will both work.
Each collection/partner will be issued information to access the dropbox:
- host: imageproc.dlib.indiana.edu
Delivering Scanned Files to DLP
Currently, image files are attached to records individually. First, create a record in Photocat, then attach an image (or multiple images) to that record. The system will automatically name the files for you as they are ingested, so you don't need to change file names locally before attaching them to a record.
We are actively working on a batch upload functionality, which will enable users to upload multiple images to Photocat, and for records to automatically be created for those images.