{
  "schema": "sync-camera-research-measurements-v1",
  "pairedComparisons": [
    {
      "label": "Packaged Electron Chromium Capture vs Native Shared Memory Bypass (1080p60)",
      "date": "2026-09-21",
      "durationSeconds": 60,
      "configuration": {
        "resolution": "1920x1080",
        "targetFps": 60,
        "arm": "packaged-electron",
        "producer": "Paced producer (apps/sync-soak/bin/paced-producer.mjs, monotonic deadline pacing)",
        "daemon": "syncd (0.2.0, POSIX shm /tmp/SyncCamera.frames)",
        "extension": "io.noisefactor.sync.camera (0.2.38), CoreMediaIO DAL Plugin",
        "baselineConsumer": "Electron 44.3.0 / Chromium 152.0.7977.78 (MediaStreamTrackProcessor via CoreMediaIO DAL, NV12)",
        "candidateConsumer": "Electron 44.3.0 / Node native IPC (POSIX shm ring buffer /tmp/SyncCamera.frames, zero-copy slot pool, direct WebGL2 texImage2D, BGRA)"
      },
      "baselineArm": {
        "receiver": "electron-chromium-baseline",
        "windowDurationSeconds": 60.002,
        "totalArrivals": 3580,
        "distinctPictures": 3580,
        "uniqueFps": 59.66467784407186,
        "consecutiveRepeats": 0,
        "repeatRatePercent": 0.0,
        "timestampIntervalMs": {
          "count": 3579,
          "unit": "ms",
          "percentileMethod": "nearest-rank on sorted data (rank = ceil(p*n), 1-based)",
          "sdMethod": "sample (n-1)",
          "mean": 16.761246158144733,
          "sd": 2.932561107297289,
          "min": 5.299999237060547,
          "max": 37.29999923706055,
          "p1": 11.0,
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          "p50": 16.80000114440918,
          "p95": 20.100000381469727,
          "p99": 20.700000762939453
        },
        "completeSecondsBelow50": 0,
        "completeSecondsBelow55": 1,
        "readerErrors": 0,
        "missingSequence": 20,
        "missingSkippedByProducer": 0,
        "missingUnexplained": 20,
        "producerSkips": 0,
        "stageLatencyMs": {
          "submitToArrival": {
            "count": 3580,
            "unit": "ms",
            "percentileMethod": "nearest-rank on sorted data (rank = ceil(p*n), 1-based)",
            "sdMethod": "sample (n-1)",
            "mean": 26.7305406964691,
            "sd": 2.3128124612130856,
            "min": 22.1669921875,
            "max": 45.666748046875,
            "p1": 23.263916015625,
            "p5": 24.467041015625,
            "p50": 26.731689453125,
            "p95": 30.267333984375,
            "p99": 30.6669921875,
            "label": "submit -> arrival",
            "description": "producer socket write (submitNs) to the reader receiving the sample: every hop",
            "clock": "cross-process (epoch ms both sides): measured bound 1.90 ms (producer anchor 1.00 ms + Chrome page anchor offset max(|start| 0.90, |end| 0.50) ms)"
          }
        },
        "accountingValid": true
      },
      "candidateArm": {
        "receiver": "electron-shm-bypass-candidate",
        "windowDurationSeconds": 60.003,
        "totalArrivals": 3600,
        "distinctPictures": 3600,
        "uniqueFps": 59.9970001499925,
        "consecutiveRepeats": 0,
        "repeatRatePercent": 0.0,
        "timestampIntervalMs": {
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          "unit": "ms",
          "percentileMethod": "nearest-rank on sorted data (rank = ceil(p*n), 1-based)",
          "sdMethod": "sample (n-1)",
          "mean": 16.666546263274764,
          "sd": 0.7284445975582996,
          "min": 14.5,
          "max": 19.0,
          "p1": 15.0,
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          "p50": 16.80000114440918,
          "p95": 17.700000762939453,
          "p99": 18.100000381469727
        },
        "completeSecondsBelow50": 0,
        "completeSecondsBelow55": 0,
        "readerErrors": 0,
        "missingSequence": 0,
        "missingSkippedByProducer": 0,
        "missingUnexplained": 0,
        "producerSkips": 0,
        "stageLatencyMs": {
          "submitToArrival": {
            "count": 3600,
            "unit": "ms",
            "percentileMethod": "nearest-rank on sorted data (rank = ceil(p*n), 1-based)",
            "sdMethod": "sample (n-1)",
            "mean": 7.8483086480034725,
            "sd": 0.5174744549610921,
            "min": 6.747802734375,
            "max": 9.748046875,
            "p1": 6.9150390625,
            "p5": 7.048583984375,
            "p50": 7.84814453125,
            "p95": 8.715576171875,
            "p99": 9.1474609375,
            "label": "submit -> arrival",
            "description": "producer socket write (submitNs) to the reader receiving the sample: every hop",
            "clock": "cross-process (epoch ms both sides): measured bound 1.50 ms (producer anchor 1.00 ms + Chrome page anchor offset max(|start| 0.50, |end| 0.10) ms)"
          }
        },
        "uploadStats": {
          "count": 3900,
          "totalMs": 2183.600046157837,
          "maxMs": 2.1000003814697266
        },
        "accountingValid": true
      },
      "reverseArm": {
        "receiver": "electron-shm-bypass-reverse",
        "windowDurationSeconds": 60.002,
        "totalArrivals": 3600,
        "distinctPictures": 3600,
        "uniqueFps": 59.99800006666444,
        "consecutiveRepeats": 0,
        "repeatRatePercent": 0.0,
        "timestampIntervalMs": {
          "count": 3599,
          "unit": "ms",
          "percentileMethod": "nearest-rank on sorted data (rank = ceil(p*n), 1-based)",
          "sdMethod": "sample (n-1)",
          "mean": 16.66668519075462,
          "sd": 0.6318478472152945,
          "min": 13.5,
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          "p1": 15.19999885559082,
          "p5": 15.5,
          "p50": 16.80000114440918,
          "p95": 17.5,
          "p99": 17.899999618530273
        },
        "completeSecondsBelow50": 0,
        "completeSecondsBelow55": 0,
        "readerErrors": 0,
        "missingSequence": 0,
        "missingSkippedByProducer": 0,
        "missingUnexplained": 0,
        "producerSkips": 0,
        "stageLatencyMs": {
          "submitToArrival": {
            "count": 3599,
            "unit": "ms",
            "percentileMethod": "nearest-rank on sorted data (rank = ceil(p*n), 1-based)",
            "sdMethod": "sample (n-1)",
            "mean": 7.780058262711864,
            "sd": 0.45650745582987007,
            "min": 6.66259765625,
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            "p95": 8.5244140625,
            "p99": 8.72998046875,
            "label": "submit -> arrival",
            "description": "producer socket write (submitNs) to the reader receiving the sample: every hop",
            "clock": "cross-process (epoch ms both sides): measured bound 1.30 ms (producer anchor 1.00 ms + Chrome page anchor offset max(|start| 0.10, |end| 0.30) ms)"
          }
        },
        "uploadStats": {
          "count": 3914,
          "totalMs": 2147.200038909912,
          "maxMs": 1.7000007629394531
        },
        "accountingValid": true
      }
    }
  ]
}