Sealing
Sealing means ensuring all data referenced in the Silverstack library and the ASC MHL history is available and hashed at a specific target, like a volume or folder. This process results in a seal that helps you document your work and allows you and others to ensure data integrity and completeness by verifying the dataset at different steps in the production pipeline, e.g., with MediaVerify.
This article will guide you through the task of creating such a seal. To learn more about the specific options, read the article about the sealing wizard.
Sealing is usually the last step after all data management activities have been executed in Silverstack, e.g., after a production day when a volume needs to be transferred to post-production. We will explain this common scenario in two cases: with all files available and with some files missing. In order to follow the steps described below, you need some data that was offloaded onto a volume using Silverstack. The article on configuring workflows explains in detail how you could create such a dataset.
1. Volume sealing#
Sealing: All files are available
Open the sealing wizard for the volume used to offload the data. The volume is scanned immediately, and the result is shown at the top of the sealing wizard.If you see two green messages with checkmarks for both the library and ASC MHL comparison, all files referenced on the volume were found. This acts as a confirmation that the volume is ready to be sealed.In case the sealing wizard finds files that are not referenced in the library or ASC MHL history, you are informed with blue info messages. Files that are not yet referenced in the ASC MHL history are not critical since they will be included during sealing.For files on the volume that are not referenced in the library, you need to decide if you want those files to be part of the exported library archive (in case you enabled this option in the seal settings).By clicking the message’s Reveal button, you are forwarded to the associated tab in the summary table where the “Library” and “ASC MHL” columns indicate with a checkmark the instance in which the file is referenced. “New” in this context means either new to the library or ASC MHL history. If files are referenced in both instances, they are sorted into “Passed.”
1.1 Seal settings#
The default seal settings are sufficient in most cases. We recommend entering basic information in the ASC MHL creator info, which can be accessed quickly via the Open… button in the seal settings. Enable the sealing logs if you would like to create a flattened ASC MHL manifest, which acts as an inventory list of the sealed volume that can be sent via email, for instance.
After checking the files and configuring the seal settings, you may now start the sealing process by clicking Seal
1.1 Sealing process#
Silverstack now calculates hashes for all files that are not yet referenced in the ASC MHL history, as you can see in the “Hashing Progress” section. The duration section shows you how much time has elapsed since the start and how long the overall process might take.When the sealing process has been completed successfully, this is highlighted with the message “Sealing completed” and a green seal checkmark.You can use the little go-to icon in the top right corner of the sealing wizard to reveal the path in Finder, where you will see a new root ASC MHL history. You can now eject the volume, close the sealing wizard, or open the path in MediaVerify (if the application is installed) for a double-check.
2. Handle missing files#
Sealing: A file is reported as missing by Silverstack and ASC MHL
Files referenced in the library or the ASC MHL history but unavailable on the selected volume are considered missing. They appear as blocking errors, clearly marked red in the sealing wizard. When they appear, the sealing wizard automatically opens the missing tab in the summary table. How to handle missing files depends on which instance reports a file as missing. For example, an OCF file was offloaded using ASC MHL and got missing for some reason. Silverstack and ASC MHL will report the file as missing since neither can find the file on the volume.To continue sealing, you first need to unregister the missing resource in the library (to solve the library error) and then tell the ASC MHL history to ignore the missing file by applying ignore patterns (to solve the ASC MHL error).
Select the missing file in the table and use Right-Click > Copy Path to copy the file path (e.g., copy and paste it as a reference for unregistering the file in the next step). Close the sealing wizard, find the missing asset in the library using the reference, and select it.Head to the general info and select the “Files & Hashes” tab. Find the resource that matches your reference and unregister it from the library with Right-Click > Unregister Resource…Open the sealing wizard again. The library error is solved, leaving only the ASC MHL error, which you can fix using the quick fix Add to ASC MHL Ignore Patterns .Sealing is now enabled again.
3. Workflow considerations#
Hashing large amounts of data may take a lot of time during sealing. The checksum creation activity allows you to create hashes for files without offloading them first. For example, in the workflow configuration window, you may append a checksum creation to a transcode activity.This allows you to hash your transcodes immediately after transcoding, reducing the time needed for sealing later. Depending on your workflow, this can be beneficial, e.g., using idle time for hashing files.
Checksum Creation vs. BackupWhen using a workflow for offloading camera cards that is configured as follows:
- Register in Library (Camera Card)
- Backup (Offload)
- Transcode (Create Dailies)
- Backup (Backup Dailies)
- Transcode (Create Dailies)
- Backup (Offload)
We recommend to use the “Create at Source” feature in the backup activity instead of a checksum creation. It becomes selectable when a backup is appended to a transcode activity and allows you to create an ASC MHL manifest at the source (in-place for the transcodes) and for the backup.