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Image Generation

The Image API provides a simple way to extract a single image frame from a media asset stored in the cloud. It is commonly used to generate images without downloading or transcoding the full media file.

The image is captured at a specific position in the source video and returned in a standard image format.

Use Cases​

The Image API is typically used to:

  • Generate thumbnail images for media assets
  • Create preview frames for asset browsers or dashboards
  • Perform quick visual verification of content
  • Support quality control and asset review workflows
  • Extract still frames without creating intermediate proxies

This endpoint is optimized for fast, lightweight, on-demand image extraction.

Image API​

The Image API is accessed using an HTTP GET request with query parameters.

GET https://api.galaxy.dolbyrasp.com/image?url=https://my_bucket/my_folder/my_file.mxf&format=png&height=280

Required Query Parameters​

  • url
    The URL of the media file to extract the image from.

Optional Query Parameters​

  • format
    The image format to return.
    Supported values: jpeg, png
    Default: jpeg

  • width
    The desired width of the image in pixels.
    If not specified, the width is calculated based on the source dimensions. If only width is specified, height is calculated from the source aspect ratio.

  • height
    The desired height of the image in pixels.
    If not specified, the height is calculated based on the source dimensions. If only height is specified, width is calculated from the source aspect ratio.

  • offset_percent
    The percentage offset into the video where the image should be captured.
    Range: 0–100
    Default: 10

  • credentials_key
    The key of stored credentials to use when accessing the media URL.

Using Credentials​

Typically, cloud content is not publicly accessable. If the provided url is an encrypted link, remember to use encodeURI() to encode the URL inside the GET call. If you have registered cloud credentials with the Dolby OptiView Engine, you can reference those credentials in the call.

GET https://api.galaxy.dolbyrasp.com/image?url=s3://my_bucket/my_folder/my_file.mxf&format=png&height=280&credentials_key=my_s3_creds

Response​

The response is a binary image returned directly in the requested format.

  • Content-Type: image/jpeg or image/png
  • The response body contains the image data

This endpoint does not return JSON metadata; the response payload is the image itself.

Notes​

  • The Image API is read-only and does not modify the source asset.
  • The exact frame captured depends on source encoding and GOP structure.
  • Width and height constraints are validated by the service.