{
  "version": "1.1.0",
  "updated": "2026-05-15T05:34:28.466141+00:00",
  "frames_jpg": {
    "total_frames": 10760,
    "face_blur_method": "MediaPipe long-range face detector + GaussianBlur(99x99, sigma=30) + 20% padding",
    "face_detection_threshold": 0.3,
    "frames_with_faces": 518,
    "faces_blurred": 519,
    "face_detection_rate": "4.81%",
    "text_blur_method": "EasyOCR (English + Hindi/Devanagari) + GaussianBlur(51x51) + 8px padding",
    "text_blur_threshold": 0.2,
    "frames_with_text_blur": 10616,
    "sensitive_text_regions_blurred": 12573,
    "overlay_band_regions_blurred": 10229,
    "overlay_band_definition": "top 80px and bottom 80px of every frame; ALL detected text in these bands is blurred",
    "sensitive_patterns": [
      "Brand: SAIL, BSL, Steel Authority",
      "Location: Bokaro, Jharkhand, India(n), Hindi/Devanagari script",
      "Other Indian steel plants: IISCO, Durgapur, Bhilai, Rourkela, Jamshedpur",
      "Area cues: Go Down (any spelling)",
      "CCTV timestamp formats (DD/MM/YYYY, HH:MM:SS, etc.)",
      "Camera ID patterns (CAM/CH/Camera + digits)"
    ],
    "elapsed_sec": 3932.2
  },
  "sample_mp4s": {
    "total_mp4s": 50,
    "total_frames_processed": 13714,
    "face_blurs": 19306,
    "sensitive_text_blurs": 3347,
    "overlay_band_blurs": 2363,
    "audio": "stripped (no audio track in re-encoded mp4s)",
    "ocr_every_n_frames": 5,
    "elapsed_sec": 1827.4
  },
  "metadata_scrubs": {
    "annotations_text_scrubbed": "6 annotations had 'Go Down' references in scene_description; replaced with 'Warehouse South Side'",
    "manifest_rows_renamed": "224 batch_manifest.csv rows had work_area='Go Down South Side' renamed to 'Warehouse South Side'",
    "camera_zones_rows_renamed": "1 row in camera_zones.csv had work_area renamed",
    "sail_railcar_id_removed": "1 annotation (clip_Tippler_1&2_WT2-LOAD_SIDE_20251126_000045_0003) had visible_equipment SAIL railcar number removed",
    "clip_ids_unchanged": "97 clip_ids containing 'Go_Down' were intentionally NOT renamed to preserve reproducibility against eval result files; the on-pixel pass blurs the visible signage"
  },
  "limitations": [
    "OCR recall is bounded; small or low-contrast text (especially partially occluded signage) may be missed",
    "Frames where Hindi script is mixed with English (Hinglish) may have partial detection",
    "MediaPipe face detection is bounded; faces <20px or non-frontal may not be blurred",
    "The 50 sample mp4s were re-anonymized at a 1-in-5 frame OCR cadence (face blur runs on every frame); sub-second signage flashes may persist"
  ]
}