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skills/mlops/computer-vision-inference/references/video-content-renaming.md

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+# Video Content Detection + Renaming — Production Script
+
+A working YOLO-based pipeline for detecting video content from frames and renaming generically-named recovered video files (FILE000.MOV pattern).
+
+## Script
+
+Saved at `/tmp/rename_videos.py` and `/tmp/rename_videos2.py` on rayserver.
+
+### Workflow
+1. List all files in the target directory starting with "FILE" (generically-named recovered files)
+2. Extract a video frame at 3 seconds using ffmpeg; fall back to 1 second for short clips
+3. Run YOLOv8n on CPU for content detection
+4. Build descriptive filename: `{people_count}_people_{object1}_{object2}.mov`
+5. Handle filename collisions with `_1`, `_2` suffixes
+6. Files with no detections → `scene.mov`
+
+### Key design decisions
+- **CPU inference** — Viable for 80-100 files at ~3-5s/file. GPU not needed for this scale
+- **ffmpeg single-frame extraction** — Much faster than processing the entire video
+- **3-second offset** — Early enough to avoid blank intros, late enough to have content
+- **startswith("FILE") guard** — Makes the script idempotent (won't rename already-named files)
+
+### Performance reference
+- **80 files**: ~4-6 minutes total (i7-10700K, CPU)
+- **~60 files** get descriptive names, **~20** remain as `scene` (blank/dark)
+
+### Full script (80-file version)
+See `/tmp/rename_videos.py` and `/tmp/rename_videos2.py` for the two-phase version that handled 80 files.
+
+### Edge cases
+- `.3GP` files are valid video containers — include them
+- Short clips (<3s): ffmpeg clips to available duration, produces a valid frame
+- Broken headers: ffmpeg hangs if file is truncated — always set `timeout=20`
+- Collisions: use `while os.path.exists(dst)` loop with incrementing counter