Accessing and Downloading Datastreams
- Navigate to your object and click the download button
- The icon will expand to display the datastreams associated with your object. Click on any of the links in the menu to download that datastream.
- See the sections below if you need to manage, add or, replace a datastream.
- To view the datastreams associated with an object in the repository, navigate to that object's page. Click the "Manage" tab.
- Click "Datastreams".
- After clicking "Datastreams" you will see this screen.
- Datastream ID (DSID) - an internal unique identifier within the scope of the digital object, for example, RELS_EXT, MODS, or TN.
- Datastream Label - the human-readable title given to a data stream. It does not need to be unique but it should be informative enough for a user to understand the purpose of the data stream.
- Versions - used to view past versions of the datastreams and revert to an early version of a particular DS to correct a mistake.
- Operations - the options in this column allow you to manage each datastream.
Add or Replace a Datastream
All Fedora Digital Objects contain datastreams which can be added, replaced or sometimes deleted. Remember that some datastreams are required and cannot be deleted.
Replace a Datastream
- Go to the object for which you want to replace a datastream. Click “Manage”.
- Click “Datastreams”.
- If the datastream already exists, you can select “replace”.
- If you want to replace the TN, or thumbnail, datastream click on “replace” on the line for that datastream ID “TN”.
- In the new window, click "Choose File" and find your new thumbnail. Click "Upload", then "Add Contents".
- This is the same process to replace any datastream you have permissions to.
Add a Datastream
- Not all content models come with thumbnail datastream. Sometimes, ingests don’t go as planned and you need to add a datastream rather than replace it.
- Go to the digital asset where you want to add a datastream.
- Click “Manage”.
- Click “Datastreams”.
- Click on “Add a datastream”.
- In the new window, fill out:
Datastream ID – the ID is an autocomplete field and datastream IDs are a controlled vocabulary. MODS is always MODS, TN is always TN, OBJ is always OBJ. If you are adding a datastream that is for preservation purposes, you can create a naming convention for that purpose, i.e. AM for Archival Master.
Datastream Label – The label can be the filename or just left with the default such as MODS Record.
- Upload your file and click “Add Datastream”
You have the ability to delete datastreams from your objects in CTDA, but we recommend that you do not.
Regenerate All Datastreams
- Go to the object for which you want to regenerate all of the datastreams. Click the Manage tab.
- Click Properties.
- Click acquire the lock and then click the Confirm button on the next page.
- After acquiring the lock, click the Regenerate all derivatives button at the bottom of the page.
- Click the Regenerate button on the next screen to start the derivative regeneration process.
- A progress bar will appear on the next page.
- Once completed, you should see a green box with the message Derivatives successfully created.
|RELS-EXT||Fedora Object to Object Relationship Metadata||All|
|MODS||MODS metadata record, created at time of ingest||All|
|DC||Dublin Core metadata record, created at time of ingest||All|
|OBJ||The original file ingested into the repository (File format for this DS will depend on the content model used)||All|
|TN||Thumbnail image, created at time of ingest||All|
|JP2||JPEG 2000 derivative, created at the time of ingest||Large Image|
|JPG||Medium-sized JPEG, created at the time of ingest and used in the standard image viewer||Large Image|
|MEDIUM_SIZE||A compressed version of the image, created at the time of ingest and used on the object's View page||Basic Image|
|PROXY_MP3||MP3 derivative, created at the time of ingest||Audio|
|PDF derivative, created at the time of ingest||Book, PDF, Newspaper|
|RELS-INT||Internal Fedora relationship metadata defining the dimensions of the JP2 datastream||Book Page, Newspaper Page|
|OCR||Optical Character Recognition file||Book Page, Newspaper Page|
|HOCR||A converted version of the OCR datastream, intended to be more human-readable||Book Page, Newspaper Page|
|COLLECTION_POLICY||Specifies which content models are associated with a particular collection||Collection|
|FULL_TEXT||Text of a PDF||Document, PDF|
|PREVIEW||Preview image, created at time of ingest||Document, PDF|
|MP4||MPEG-4 video derivative, created at time of ingest||Video|
|MKV||Matroska video derivative, created at time of ingest||Video|