directus/docs/reference/api/assets.md

Assets

The /assets endpoint can be used to stream/retrieve the actual file contents from files managed in Directus.

Accessing an Original File

The location of your actual file originals is based on the project's configuration, but you can consistently access them via the API using the following URL.

example.com/assets/<file-id>
example.com/assets/1ac73658-8b62-4dea-b6da-529fbc9d01a4

Original File Used — 602KB and 1800x1200

::: warning Direct File Access

While you may technically be able to expose your storage adapters root filesystem and access your raw files through there, it is recommended that you always use the Directus API. This is the only way that you can take advantage of file permissions and other built-in features.

:::

Requesting a Thumbnail

Fetching thumbnails is as easy as adding query parameters to the original file's URL. If a requested thumbnail doesn't yet exist, it is dynamically generated and immediately returned. When requesting a thumbnail, the following parameters are all required.

• fit — The fit of the thumbnail while always preserving the aspect ratio, can be any of the following options:
  • cover — Covers both width/height by cropping/clipping to fit
  • contain — Contain within both width/height using "letterboxing" as needed
  • inside — Resize to be as large as possible, ensuring dimensions are less than or equal to the requested width and height
  • outside — Resize to be as small as possible, ensuring dimensions are greater than or equal to the requested width and height
• width — The width of the thumbnail in pixels
• height — The height of the thumbnail in pixels
• quality — The quality of the thumbnail (0 to 100)
• withoutEnlargement — Disable image up-scaling
• download — Add Content-Disposition header and force browser to download file

example.com/assets/<file-id>?fit=<fit>&width=<width>&height=<height>&quality=<quality>
example.com/assets/1ac73658-8b62-4dea-b6da-529fbc9d01a4?fit=cover&width=200&height=200&quality=80

Alternatively, you can reference a specific thumbnail by its preset key.

• key — This key of the Storage Asset Preset, a shortcut for the above parameters

example.com/assets/<file-id>?key=<preset-key>
example.com/assets/1ac73658-8b62-4dea-b6da-529fbc9d01a4?key=card

Cover vs Contain

For easier comparison, both of the examples below were requested at 200 width, 200 height, and 75 quality. The cover thumbnail forces the dimensions, trimming the outside edges as needed. The contain thumbnail always maintains its aspect ratio, shrinking the image to fit within the dimensions and adding "letterboxing" as needed.

Cover	Contain
8KB • 200x200	6KB • 200x133

::: tip Aspect Ratio

Images are never stretched or distorted even when changing the aspect ratio.

:::

Quality vs Filesize

The quality parameter can be any integer from 0-100. Qualities closer to 0 have lower filesizes, but also poor image quality due to compression artifacts. Values closer to 100 have larger filesizes, but better image quality. Below are four possible qualities (200x200 cover) to visually compare the balance between compression and filesize.

25%	50%	75%	100%
4KB	6KB	8KB	38KB