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We are aware of the recently disclosed PHP2Shell vulnerabilities (CVE-2026-109618 and CVE-2026-109619) and can confirm Filestack is not impacted by these vulnerabilities.

Image Captioning

Image captioning is a Filestack intelligence task that returns a short sentence describing what an image shows.

How It Runs

  • Synchronously in the Processing API with the caption task. The request needs a security policy and signature.
  • As a task in Filestack Workflows

Examples

  • https://cdn.filestackcontent.com/security=p:POLICY,s:SIGNATURE/caption/HANDLE
  • Chained after another task: .../resize=h:1000/caption/HANDLE
  • With an external URL or a storage alias, add the API key to the URL

Uses

  • Alt text for images
  • Searchable descriptions in media libraries

Documentation

Read the Filestack documentation page for this term.

Open the documentation