{
  "run_id": "svg-to-png-20261031-01",
  "measurement_date": "2026-10-31",
  "provenance": "Actual SVG file input \u2192 canvas-rendered PNG \u2192 browser download; independently decoded with Pillow. Complete PNG file bytes. Controls are real browser downloads too.",
  "browser": "156.0.8078.4",
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      ],
      "corner_rgba": [
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      ],
      "observed": "Retained: soft alpha extends beyond the hard rectangle.",
      "metrics": {
        "nonzero_alpha_outside_hard_rect": 6132,
        "no_filter_control_outside": 0,
        "partial_alpha_pixels": 10948
      },
      "file": "gaussian-blur-1x.png",
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      ],
      "corner_rgba": [
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      ],
      "observed": "Retained: soft alpha extends beyond the hard rectangle.",
      "metrics": {
        "nonzero_alpha_outside_hard_rect": 25568,
        "no_filter_control_outside": 0,
        "partial_alpha_pixels": 45404
      },
      "file": "gaussian-blur-2x.png",
      "sha256": "c05d52040a98f82702c78a4ae08dc23d81768f2d7e380683e783b245cfc95d28"
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    {
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      ],
      "corner_rgba": [
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      ],
      "observed": "Retained: soft alpha extends beyond the hard rectangle.",
      "metrics": {
        "nonzero_alpha_outside_hard_rect": 57972,
        "no_filter_control_outside": 0,
        "partial_alpha_pixels": 103028
      },
      "file": "gaussian-blur-3x.png",
      "sha256": "84b3e1ca3aa13e090ed4a585e579c9b501114b9c50bcee9b57874b10ed6e9ad1"
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      ],
      "corner_rgba": [
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      ],
      "observed": "Retained: linear and radial samples both vary in color.",
      "metrics": {
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          ],
          "linear_right": [
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          ],
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          ],
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      "sha256": "baa2a499c8eb275dd89920a93e18ae3f7b0ee4b3022bb9b95a6cad2ffbf955d1"
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      ],
      "corner_rgba": [
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      ],
      "observed": "Retained: linear and radial samples both vary in color.",
      "metrics": {
        "sample_rgba": {
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          ],
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      "corner_rgba": [
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      ],
      "observed": "Retained: linear and radial samples both vary in color.",
      "metrics": {
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          ],
          "linear_right": [
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      "corner_rgba": [
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      ],
      "observed": "Retained: red stroke and yellow system-font glyph fill both remain.",
      "metrics": {
        "red_stroke_pixels": 2235,
        "no_stroke_control_red_pixels": 0,
        "yellow_fill_pixels": 5735
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      "file": "system-font-stroke-1x.png",
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      "corner_rgba": [
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      ],
      "observed": "Retained: red stroke and yellow system-font glyph fill both remain.",
      "metrics": {
        "red_stroke_pixels": 10231,
        "no_stroke_control_red_pixels": 0,
        "yellow_fill_pixels": 22740
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      "file": "system-font-stroke-2x.png",
      "sha256": "bff827e5c569fbc35f639de930ce1c75513183dd9ddc74ba5b2c918b6fa3bb54"
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      "corner_rgba": [
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      "observed": "Retained: red stroke and yellow system-font glyph fill both remain.",
      "metrics": {
        "red_stroke_pixels": 25094,
        "no_stroke_control_red_pixels": 0,
        "yellow_fill_pixels": 50204
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      "file": "system-font-stroke-3x.png",
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}