{
  "test": "Single-variable JPEG quality export comparison",
  "input": "synthetic-source.png",
  "input_bytes": 173383,
  "dimensions": [
    1200,
    1680
  ],
  "synthetic_person_free_test_card": true,
  "python_pillow_version": "12.3.0",
  "fixed_export_settings": {
    "subsampling": 0,
    "optimize": false,
    "progressive": false,
    "mode": "RGB",
    "resize": false
  },
  "variable": "quality setting only",
  "observations": [
    {
      "file": "quality-92.jpg",
      "format": "JPEG",
      "quality_setting": 92,
      "bytes": 281379,
      "width": 1200,
      "height": 1680,
      "mean_absolute_error_rgb_0_255": 0.564017,
      "decoded_rgb_sha256": "c8ed856280dc6a7aa695779fcdfb21f6954972fc672e3c0f9947dc1b7c762a66"
    },
    {
      "file": "quality-82.jpg",
      "format": "JPEG",
      "quality_setting": 82,
      "bytes": 210967,
      "width": 1200,
      "height": 1680,
      "mean_absolute_error_rgb_0_255": 0.854015,
      "decoded_rgb_sha256": "03a47ec21ca5c4b3e228c3b972704d52359ea6536a5680eb78e245090c8ffcb3"
    },
    {
      "file": "quality-72.jpg",
      "format": "JPEG",
      "quality_setting": 72,
      "bytes": 176788,
      "width": 1200,
      "height": 1680,
      "mean_absolute_error_rgb_0_255": 1.216418,
      "decoded_rgb_sha256": "85018c4a3805b8e831b54a2f3efcab3730a6ed83ac5650dae38b4bf040c561ec"
    },
    {
      "file": "quality-62.jpg",
      "format": "JPEG",
      "quality_setting": 62,
      "bytes": 159050,
      "width": 1200,
      "height": 1680,
      "mean_absolute_error_rgb_0_255": 1.528031,
      "decoded_rgb_sha256": "50b06cbb713af53e9075077b78b66b323135561a813b8e5f2caa92efd5604b2d"
    },
    {
      "file": "quality-52.jpg",
      "format": "JPEG",
      "quality_setting": 52,
      "bytes": 148061,
      "width": 1200,
      "height": 1680,
      "mean_absolute_error_rgb_0_255": 1.797779,
      "decoded_rgb_sha256": "4becf0e27c011c3ae856d349c66b4207e1a69de07f2bcc5429ce347eb619d7b1"
    }
  ],
  "limitations": "Synthetic pixels do not predict file size or visible photographic detail for any person's portrait or upload portal. Mean absolute RGB error is a reproducible numeric difference, not a visual-quality score."
}