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Pre-Render Frame Cache

Pre-Render Frame Cache warms the Timeline Film Strip thumbnail cache ahead of time so selecting events feels instant, even on slower machines. Use it when the Film Strip is enabled and the first selection of each event feels sluggish while frames are extracted.

When to Use It​

The Film Strip shows a strip of video frames around the selected event’s start time on the Timeline. On first selection, Closed Caption Creator extracts those frames with FFmpeg and stores them in a local disk cache. Later selections of the same (or nearby) times reuse the cache and load quickly.

On older or lower-powered systems, that first extraction pass can introduce a noticeable delay. Pre-Render Frame Cache runs the same extraction for every event start in the project in one batch, so you can start the job once, wait for it to finish, then work with the Film Strip without waiting on per-event generation.

Requirements​

  • Desktop (Electron) application
  • Local video media loaded in the project (streaming / remote-only paths are not supported)
  • Film Strip settings configured under Edit > Options > Editor (optional but recommended so the strip is visible while you work)

The menu item is disabled when film strip generation is not available for the current media.

How to Run Pre-Render Frame Cache​

  1. Open your project with local video media loaded.
  2. Ensure you have events in the project (the job uses each event’s start time).
  3. Go to AI Tools > Pre-Render Frame Cache.
  4. A progress dialog shows how many unique frames have been resolved. You can Cancel at any time; frames already written remain in the cache and a later run will skip them.
  5. When complete, a toast reports how many frames were newly generated versus already cached.

The job uses your current Film Strip Frames setting (Edit > Options > Editor) and the same thumbnail width as the live Film Strip, so the cache matches what the Timeline displays.

Tips for Slower Machines​

  • Run Pre-Render Frame Cache after your event list is in place (or after a large import), before intensive spotting on the Timeline.
  • If you cancel early, re-run later — existing frames are reused and only missing frames are generated.
  • Lowering Film Strip Frames in Editor Options reduces how many thumbnails are generated per event (faster pre-render and less disk use), at the cost of a narrower strip.
  • Pre-rendering does not require the Film Strip to be visible, but enable Show Film Strip when you are ready to use it.