{
  "prepared_at": "2026-10-26T16:03:19.315770+08:00",
  "source": "Existing public NASA/scikit-image astronaut portrait; no private image",
  "pillow_version": "12.3.0",
  "local_app_sha256": "77d72d141ecbc422846807d6e6ceadc79aaca23720ff0b30572434223b7bd835",
  "order": "baseline3, tone3, rotation3, resolution3, compression3; log each immediately; no omitted failures",
  "scope": "Image processing experiment, not actual lighting or physical head-angle experiment",
  "conditions": [
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      "id": "baseline",
      "variable": "Baseline",
      "value": "512x512 RGB PNG, unchanged",
      "file": "baseline.png",
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      "id": "tone",
      "variable": "Synthetic tone, not physical lighting",
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      "file": "tone.png",
      "sha256": "c6fafb5e80ac4a3c6f1779f0804c8e75c6fff33e262e6f6c943dc5f7f3289155",
      "width": 512,
      "height": 512,
      "bytes": 435085
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    {
      "id": "rotation",
      "variable": "Image-plane rotation, not head turn",
      "value": "+10 degrees Pillow BICUBIC fixed512 white fill",
      "file": "rotation.png",
      "sha256": "d195b5e5d1077265d0bfc334cd2efcee44b921ecb1f92119744ff4752010b16b",
      "width": 512,
      "height": 512,
      "bytes": 410579
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    {
      "id": "resolution",
      "variable": "Resampling",
      "value": "512 to256 pixels LANCZOS PNG",
      "file": "resolution.png",
      "sha256": "35104b000dbc1b242d19203de6c8be1077cafe367723a8bca39e7f21657d9122",
      "width": 256,
      "height": 256,
      "bytes": 117804
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    {
      "id": "compression",
      "variable": "JPEG encoding",
      "value": "quality20 subsampling2 optimizeFalse fixed512",
      "file": "compression.jpg",
      "sha256": "2487f1c581aa5ebefed0601d78f0b807144f0099795ce67ea7f7b7eeb8a94e2d",
      "width": 512,
      "height": 512,
      "bytes": 16678
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  ]
}