Parameters
To maximize the consistency between QC Items the values that can be used for Input and Output Parameters are managed in (versioned) Parameter lists for:
- Types
- Representations
- Units
- Ranges
When QC Items are created, editors are encouraged to choose from existing 'official' Parameter values (as these are the only ones that show in the dropdown lists for Types, Representations, Units, Ranges). They can however also suggest new Parameter values.
Newly proposed values do NOT appear in the dropdown lists, but will be added as 'unofficial' to Parameter Lists managed by Workflow Managers. These 'unofficial' values can subsequently (in case of wide agreement) be elevated to 'official'.
Currently work is ongoing to improve the lists of Parameters based on the data of the QC Items that were created before this managed approach was introduced.
Versioning
As with most information in QC.EBU.IO, the parameters are versioned.
This means that when a Unit or Representation is updated, ideally the corresponding Type and potentially any QC Item using those should be updated to a new version, too.
Note that when you select fromt the listboxes in the QC Item interface, these always refer to the latest versions of the parameters, but stored information in existing QC Items does not necessarily.
Also the validation logic normally checks against the latest versions of the parameters.
Example:
- An editor uses Type SometypeA v1 in a QC Input Parameter, including the SomeUnit v1 that SomeTypeA includes as an option.
- SomeUnit v1 gets updated to SomeUnit v2, but SomeTypeA stays at v1.
- The next time the editor opens the QC Item, it still sees SomeTypeA and SomeUnit (but effectively they both still refer to v1).
- When trying to save/publish, the editor may get a validation error, as the system checks if the latest versions are used, which is not the case for SomeUnit.
- However, after having addressed that, the editor may get an error that SomeUnit (v2) is not part of SomeTypeA (v1)!
- Updating the Type when the Unit is updated (to make sure all are linked versions are the latest) avoids this problem.
Work is underway to automate/simplify some of this updating. It also should be noted that although parameters are versioned, often the changes between them are limited (e.g. updated remarks field) and not relevant for what is displayed in related QC Items (e.g. when a Type name stays the same).