{
  "title": "Memoria WhatsApp-equivalent compression lab",
  "date": "2026-08-26",
  "lab_note": "Bench test, not a household survey. Standard recipe matches the on-site WhatsApp Photo Quality Checker (1600 px / JPEG 40). HD recipe is 3024 px / JPEG 70. WhatsApp's live encoder can differ by client version and HD toggle.",
  "method": {
    "original_jpeg_quality": 92,
    "whatsapp_standard": {
      "max_long_edge_px": 1600,
      "jpeg_quality": 40,
      "subsampling": "4:2:0"
    },
    "whatsapp_hd": {
      "max_long_edge_px": 3024,
      "jpeg_quality": 70,
      "subsampling": "4:2:0"
    },
    "resampler": "LANCZOS",
    "library": "Pillow 12.3.0"
  },
  "n_frames": 12,
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      "mean": 1.29,
      "median": 1.17,
      "min": 0.48,
      "max": 2.45
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      "n": 12,
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      "median": 107.05,
      "min": 56.6,
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      "mean": 13.07,
      "median": 11.8,
      "min": 8.2,
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      "min": 87.8,
      "max": 96.0
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      "mean": 84.17,
      "median": 84.3,
      "min": 84.0,
      "max": 84.3
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    "wa_hd_kb": {
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      "mean": 571.38,
      "median": 529.8,
      "min": 239.0,
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    "wa_hd_ratio": {
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      "mean": 2.26,
      "median": 2.2,
      "min": 2.0,
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    "wa_hd_size_cut_pct": {
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      "mean": 55.48,
      "median": 54.75,
      "min": 49.1,
      "max": 63.1
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  },
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      "name": "frame-1015",
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      "name": "frame-1011",
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      "name": "frame-1025",
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      "name": "frame-1036",
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      "name": "frame-106",
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      "name": "frame-237",
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      "name": "frame-433",
      "scene": "Wildlife, mixed midtones",
      "source": "Lorem Picsum id=433 4000x2670",
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      "wa_std_size_cut_pct": 89.6,
      "wa_std_pixel_cut_pct": 84.0,
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      "name": "frame-1074",
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      "source": "Lorem Picsum id=1074 4032x2268",
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      "name": "frame-1084",
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    },
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      "name": "frame-338",
      "scene": "Outdoor scene with people-scale subjects",
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      "wa_hd_size_cut_pct": 49.1,
      "wa_hd_pixel_cut_pct": 42.9
    },
    {
      "name": "frame-453",
      "scene": "Group-scale outdoor photograph",
      "source": "Lorem Picsum id=453 4032x2268",
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      "orig_h": 2268,
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      "orig_bytes": 501501,
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      "wa_std_bytes": 57915,
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      "wa_std_size_cut_pct": 88.5,
      "wa_std_pixel_cut_pct": 84.3,
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      "wa_hd_bytes": 244771,
      "wa_hd_kb": 239.0,
      "wa_hd_ratio": 2.0,
      "wa_hd_size_cut_pct": 51.2,
      "wa_hd_pixel_cut_pct": 43.8
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  ],
  "peer_review_anchor": {
    "citation": "Seufert, Poignee, Seufert, Hossfeld. Share and Multiply. IEEE Access 11:25401-25414, 2023.",
    "doi": "https://doi.org/10.1109/access.2023.3254913",
    "field_finding": "Average generated traffic per WhatsApp image 174.5 kB; mean compression ratio 14.7; originals up to 10 MB typically under 700 kB on the wire."
  }
}