DFS 8.0.2 - 5 Working with Assets

Owned by Mathias Mattson (MHM)
Last updated: Sept 25, 2017 by Martin Ulisse

Some of the added complexities of working with assets, compared to working with Sitecore images, are qualities and derived or sub-assets.

The qualities represent various representations of the very same asset that Digizuite™ DAM generates and DAM for Sitecore makes available. At any time when an asset is requested, it requires both an id as well as quality. DAM for Sitecore handles some of this behind the scenes, but understanding it is still important.

Each asset will have a source quality, the one that was uploaded. The other qualities of an asset each have a separate data file matching the quality. One asset has many files, one per quality.

The derived assets are assets that are created from an original source asset. A derived asset has qualities too, and in some cases the same qualities as the original asset.

Typically, a derived asset is a cropped version of an image, but a PowerPoint also creates derived assets, one for each slide in the PowerPoint. The Digizuite™ job engine will automatically create an image of each slide in the PowerPoint, as derived assets of the PowerPoint asset.

The derived assets from a PowerPoint are images who have qualities as images, but they will inherit metadata from the PowerPoint.

5.1 Understanding the Cache

DAM for Sitecore only stores the data about the asset inside Sitecore. The data files are stored in the Sitecore Media Cache. Each quality that DAM for Sitecore requests is stored inside the standard media cache in Sitecore. The Sitecore media cache is only used for the asset type images, all other asset types are fetched from the Digizuite™ DAM system.

If you have experience from earlier versions of DAM for Sitecore, this is a change, and the DigiCache is no longer a part of DAM for Sitecore.

5.2 URL parameters for assets

DAM for Sitecore uses its own media controller to retrieve an asset from Sitecore Media Cache. This is an example of a path to an asset:

<img src="/media/0bb91f03a754425cbcee035539a0ed24/22901-preview" />

The syntax of the url is: media/[SiloId]/[AssetId]-[Quality]/resize/[Width]x[Height]/options/[Options]

And each parameter described:

Field

Description

SiloId

This is the Id of the silo that has the asset requested.

AssetId

Is the Id of the asset that is requested.

Quality

Overrides the quality specified in the Sitecore field.

Quality supports both 'by name' and 'by id'

Resize

Only applies to image assets.

One of the concepts and principles when using a DAM system is to use specific qualities for every use. If images are needed in different sizes, it should be configured in Digizuite™ DAM.

However, there is a resize feature.

Width How wide the image will be in pixels.

Height How high the image will be in pixels.

By default a resize does not keep aspect ratio, but you can set an option to keep aspect ratio.

Options

Options is a pipe separate list and can contain these options:

download - Will download the asset requested.

keepaspectratio - Will enforce aspect ratio on from the original asset, if a resize is requested.

upscaleallowed - Will allow upscaling an image. The default is to disallow that.

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