Extracting Metadata from files - changes from v5 to v6
For the purposes of this FAQ, the term metadata refers to descriptive, non-image data embedded in a file. Common examples are IPTC field information entered using Adobe Photoshop's File Info feature or EXIF information which usually contains detail about camera settings at time of exposure for images captured using digital cameras.
This FAQ assumes you are familiar with handling metadata in previous versions of Portfolio and describes how the procedure has changed in v6.
Among the more revolutionary changes to Portfolio v6.x are changes to the process of extracting embedded information (metadata) from files while adding or updating records. The main changes revolve around the restructuring of v5's Advanced Cataloging Options.
What was 'built in'? Portfolio v5.x contained built-in tag mappings to extract IPTC data from all the fields in Photoshop's File Info feature as well as some TIFF tags.
Metadata Extraction Options:
In version 5.x, options for extraction of metadata were set through the Catalog -> Cataloging Options dialog. This dialog box contained separate settings, accessible through tabs, for Add and Update Operations enabling users to discriminate between what are often two different and distinct aspects of Portfolio workflow. Options available in each tab were:
- Thumbnail: size, quality, extract/generate. Note the difference between extracting an embedded thumbnail, forcing Portfolio/QuickTime to generate a thumbnail and no thumbnailing. The latter is appropriate during updating.
- Extract Keywords: on/off, merge or replace. This specifically controlled keywords embedded in files using tag #537.
- Extract Description: (on/off, replace or append): This feature controlled extraction of all embedded metadata (e.g. IPTC fields) other than the Keywords field, not just the Description field.
What is 'built in'? Portfolio v6.0 now contains built-in tags to extract some types of EXIF data contained in digital camera files. Otherwise, no change.
Metadata Extract Options:
In version 6.x, these options are now found under the Catalog -> Advanced Cataloging Options item but their behaviour has changed and options are limited. The most noticeable change is that there are no longer separate sets of options for when adding and when updating. So, how does metadata extraction work now?
- Extract/Generate Thumbnail: Catalog -> Advanced Catalging Options -> Thumbnails dialog.
Thumbnail size and quality options and behaviours are as version 5x. Unchecking the 'extract thumbnail' option assumes you are opting to generate a thumbnail. This dialog sets your preferences for both adding and regenerating/re-extracting a thumbnail (the latter via Item -> Regenerate Thumbnail).
- Extract Keywords: Catalog -> Advanced Cataloging Options -> Properties dialog, Extract Keywords.
As in v5.x, you can specify whether Keywords will be merged or replaced and turn extraction on or off. This dialog sets your preferences for both adding and updating files. For understand how this feature interacts with the new Cataloging Options dialog assignment feature, see here.
- Extract Description: Catalog -> Advanced Cataloging Options -> Properties dialog, Extract Description.
As in v 5.x, you can specify whether to replace or append a Description, but the similarity ends there. In v 5.x, settings for 'Extract Description' included extracting all recognizable embedded fields except Keywords. In v6.x, Description applies only to the IPTC Caption (tag #632) or TIFF Description (tag #270) tagged metadata. For information on how this feature interacts with the new Cataloging Options dialog, see here. For Information on how Custom Field information is extracted, see the next bullet point below.
- Extracting Metadata from other fields: Catalog -> Advanced Cataloging Options -> Mappings dialog.
In v5.x, after Custom Fields were created and mapped to recognized built-in tags, extraction of metadata for all such fields could be turned on/off through the Extract Description dialog for adding and updating. In v6.x, extraction from each field is controlled exclusively through the mappings tab accessible through the Advanced Cataloging Options Mappings dialog. This means that in order to enable or disable or modify method (replace or append) you must change the mapping state for that specific field/tag combination via the Edit Mapping dialog. If you want to disable all custom mapped fields, you must change the settings for each such field mapping individually. For Information on how this feature interacts with the new Cataloging Options dialog, see here.
[Thanks to L M Galbraith for the testing behind this article]
Question: Extracting Metadata from files - changes from v5 to v6 [FAQ00305.htm]
Last Update:- 31 May 2006