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Keyframe thumbnails

media.process.thumbnails_keyframe

Sapsan creates JPEG thumbnails from keyframes of the stream’s video track.

Configuration

streams:
  - name: cam1
    inputs:
    - rtsp:
        url: rtsp://admin:password@10.0.0.5/stream0
    thumbnails:
    - keyframe:
        track: v1           # source video track
        width: 320          # default 320 if no size is set, minimum 32
        height: 180
        every: 3gop         # capture every 3rd GOP (default: every GOP)
      dvr: true

every must be greater than 0. Frame dimensions must be at least 32.

See also: HTTP thumbnails.

Getting screenshots

What URL
Current stream frame http://server/streaming/live-preview-jpeg/<stream>
Frame of a specific track http://server/streaming/track-preview-jpeg/<stream>/<track>
Frame from the archive http://server/streaming/v/<stream>/image/<track>/<utc_ms>.jpg

Screenshots in the archive

With dvr: true frames are written into the archive as a separate JPEG track with real frame dimensions. In the archive's DASH manifest it is exposed as a standard thumbnail tile AdaptationSet (http://dashif.org/guidelines/thumbnail_tile) — players that support timeline thumbnails pick it up automatically.

Next steps

Archive frame previews

  • A JPEG frame from the screenshot track: http://server/streaming/v/<stream>/image/<track>/<utc_ms>.jpg
  • An MP4 fragment of an archive moment: http://server/streaming/dvr-preview-mp4/<stream>/<utc_ms> — a short fragment from a keyframe; the server picks the lowest-resolution track for the preview itself.