"AI finds your best clips" sounds like magic until you know what's actually happening underneath. It's a fairly straightforward pipeline once you break it down — and understanding it makes the suggestions much easier to use well.
Step 1: Transcribe with word-level timestamps
Before anything can be scored, the video needs a transcript where every word has a start and end time. This is what lets a suggested clip's boundaries line up precisely with the spoken audio, down to the word.
Step 2: An LLM reads the transcript in windows
For long videos, the full transcript is split into overlapping time windows (so a 90-minute video isn't dumped into one giant prompt). A language model reads each window and proposes clip candidates — a start time, an end time, a title, and two things worth understanding:
- Hook reason — a plain-English explanation of why this moment was picked: a strong opening line, a complete story, a contrarian claim, an emotional beat.
- Viral score — a 0–100 estimate of how strong that hook is, used to rank suggestions against each other.
Step 3: Merge overlapping suggestions
Because long videos are analyzed in overlapping windows, the same moment can get suggested twice near a window boundary. Overlapping candidates are de-duplicated, keeping the higher-scored version, so the final list doesn't double-count.
Step 4: You review, not the AI
The output is a ranked list, not an automatic export. You look at the hook reason, sort by score or duration, and approve, refine, or reject each one — the AI narrows a 60-minute video down to a short list worth watching, instead of you scrubbing the whole thing.
Why only text is sent to the AI: because the model reasons over transcript text, not video frames, only that text needs to leave your device — the video itself can stay local the whole time.
Groq or OpenAI — does it matter which?
Both are OpenAI-compatible chat/completions APIs under the hood, so the pipeline works the same either way. Groq is generally faster and has a more generous free tier; OpenAI's models are a common default. ClipSonic lets you pick per feature, using your own API key.
Want to see it on your own video? Download ClipSonic free and run highlight detection on a real upload.