{
  "date": "2026-11-05 Asia/Tokyo",
  "source": {
    "file": "stereo-source.mp4",
    "bytes": 127128,
    "sha256": "eaea51b4907e6d7c3d2bc4a36771056de92579314b24539915598ddb6f9445b0",
    "width": 480,
    "height": 270,
    "audioChannels": 2,
    "audioSamplesPerChannel": 288768,
    "audioSampleRate": 48000,
    "audioSeconds": 6.016,
    "fullDecodeExit": 0,
    "windows": [
      {
        "window": "Left-only",
        "startSeconds": 0.75,
        "endSeconds": 1.25,
        "samplesPerChannel": 24000,
        "leftRMS": 0.21206828876024,
        "rightRMS": 0.0,
        "peakHz": [
          440.0,
          null
        ],
        "oppositeToWantedRMS": 0.0
      },
      {
        "window": "Right-only",
        "startSeconds": 2.75,
        "endSeconds": 3.25,
        "samplesPerChannel": 24000,
        "leftRMS": 0.0,
        "rightRMS": 0.21208976007327823,
        "peakHz": [
          null,
          880.0
        ],
        "oppositeToWantedRMS": 0.0
      },
      {
        "window": "Both distinct tones",
        "startSeconds": 4.75,
        "endSeconds": 5.25,
        "samplesPerChannel": 24000,
        "leftRMS": 0.21207886294818945,
        "rightRMS": 0.21209759360961009,
        "peakHz": [
          440.0,
          880.0
        ]
      }
    ]
  },
  "formulas": {
    "duration": "samplesPerChannel / 48000",
    "RMS": "sqrt(sum(x[n]^2) / N), float PCM normalized to full scale 1, channels never downmixed",
    "oppositeToWantedRMS": "rightRMS / leftRMS in left-only window; leftRMS / rightRMS in right-only window",
    "peakHz": "maximum Hann-windowed FFT magnitude; 24000 samples at48000Hz give2Hz bin spacing; low-amplitude peak is not interpreted as useful wanted audio"
  },
  "note": "Windows are measured observations, not universal quality thresholds or bit-exact sound preservation.",
  "alignment": {
    "method": "maximize Pearson correlation of 10ms RMS envelopes combined across both channels, testing lag -250..250ms; positive means saved audio later",
    "binSeconds": 0.01,
    "bestLagSeconds": 0.04,
    "bestCorrelation": 0.9997329650499406,
    "candidates": [
      {
        "lagBins": -25,
        "correlation": 0.42245791182231285
      },
      {
        "lagBins": -24,
        "correlation": 0.4440273570565312
      },
      {
        "lagBins": -23,
        "correlation": 0.46546520492433474
      },
      {
        "lagBins": -22,
        "correlation": 0.48678094011223216
      },
      {
        "lagBins": -21,
        "correlation": 0.5080158243154874
      },
      {
        "lagBins": -20,
        "correlation": 0.5293517561168597
      },
      {
        "lagBins": -19,
        "correlation": 0.5505778091352813
      },
      {
        "lagBins": -18,
        "correlation": 0.5716795113812309
      },
      {
        "lagBins": -17,
        "correlation": 0.5926105077511625
      },
      {
        "lagBins": -16,
        "correlation": 0.6134423994695898
      },
      {
        "lagBins": -15,
        "correlation": 0.6343977013367306
      },
      {
        "lagBins": -14,
        "correlation": 0.6552176464890171
      },
      {
        "lagBins": -13,
        "correlation": 0.6759269375078418
      },
      {
        "lagBins": -12,
        "correlation": 0.6965337849245096
      },
      {
        "lagBins": -11,
        "correlation": 0.7170574581686675
      },
      {
        "lagBins": -10,
        "correlation": 0.7376817399100102
      },
      {
        "lagBins": -9,
        "correlation": 0.7581749391568484
      },
      {
        "lagBins": -8,
        "correlation": 0.7785474550135688
      },
      {
        "lagBins": -7,
        "correlation": 0.7987670304882982
      },
      {
        "lagBins": -6,
        "correlation": 0.8189008477636518
      },
      {
        "lagBins": -5,
        "correlation": 0.8391714004496011
      },
      {
        "lagBins": -4,
        "correlation": 0.859307565103626
      },
      {
        "lagBins": -3,
        "correlation": 0.8793394534113315
      },
      {
        "lagBins": -2,
        "correlation": 0.8992555481810409
      },
      {
        "lagBins": -1,
        "correlation": 0.9190912090123973
      },
      {
        "lagBins": 0,
        "correlation": 0.938965465308107
      },
      {
        "lagBins": 1,
        "correlation": 0.9586975437738039
      },
      {
        "lagBins": 2,
        "correlation": 0.9783515070721086
      },
      {
        "lagBins": 3,
        "correlation": 0.9945322629094079
      },
      {
        "lagBins": 4,
        "correlation": 0.9997329650499406
      },
      {
        "lagBins": 5,
        "correlation": 0.990720132914764
      },
      {
        "lagBins": 6,
        "correlation": 0.9728495076305707
      },
      {
        "lagBins": 7,
        "correlation": 0.9528571079899174
      },
      {
        "lagBins": 8,
        "correlation": 0.9327303641184262
      },
      {
        "lagBins": 9,
        "correlation": 0.9124753629731482
      },
      {
        "lagBins": 10,
        "correlation": 0.8923145833320734
      },
      {
        "lagBins": 11,
        "correlation": 0.8720753124296143
      },
      {
        "lagBins": 12,
        "correlation": 0.8517939527755813
      },
      {
        "lagBins": 13,
        "correlation": 0.8313566831177959
      },
      {
        "lagBins": 14,
        "correlation": 0.8107815851909637
      },
      {
        "lagBins": 15,
        "correlation": 0.7902631743338705
      },
      {
        "lagBins": 16,
        "correlation": 0.7696236464999777
      },
      {
        "lagBins": 17,
        "correlation": 0.7489412023823669
      },
      {
        "lagBins": 18,
        "correlation": 0.7281527344770798
      },
      {
        "lagBins": 19,
        "correlation": 0.7072365885549518
      },
      {
        "lagBins": 20,
        "correlation": 0.6863748728410776
      },
      {
        "lagBins": 21,
        "correlation": 0.6654341200194551
      },
      {
        "lagBins": 22,
        "correlation": 0.6444429133642932
      },
      {
        "lagBins": 23,
        "correlation": 0.6232843293162783
      },
      {
        "lagBins": 24,
        "correlation": 0.601981394193373
      },
      {
        "lagBins": 25,
        "correlation": 0.5807273510611026
      }
    ],
    "uncertainty": "10ms envelope grid, not sample-accurate AV synchronization; guarded half-second windows avoid transitions"
  },
  "output": {
    "file": "stereo-result.webm",
    "bytes": 257057,
    "sha256": "98bd6ded3345ebc8e6d2c46777bb340b95592faa28323c76d9514420584e342f",
    "width": 480,
    "height": 270,
    "audioChannels": 2,
    "audioSamplesPerChannel": 288000,
    "audioSampleRate": 48000,
    "audioSeconds": 6.0,
    "fullDecodeExit": 0,
    "windows": [
      {
        "window": "Left-only",
        "startSeconds": 0.79,
        "endSeconds": 1.29,
        "samplesPerChannel": 24000,
        "leftRMS": 0.21207620117584328,
        "rightRMS": 1.2965487680668105e-15,
        "peakHz": [
          440.0,
          0.0
        ],
        "oppositeToWantedRMS": 6.113598606907219e-15
      },
      {
        "window": "Right-only",
        "startSeconds": 2.79,
        "endSeconds": 3.29,
        "samplesPerChannel": 24000,
        "leftRMS": 1.4484427332373337e-15,
        "rightRMS": 0.2122958202036645,
        "peakHz": [
          0.0,
          880.0
        ],
        "oppositeToWantedRMS": 6.822756716772758e-15
      },
      {
        "window": "Both distinct tones",
        "startSeconds": 4.79,
        "endSeconds": 5.29,
        "samplesPerChannel": 24000,
        "leftRMS": 0.21247670596936807,
        "rightRMS": 0.21228981557728696,
        "peakHz": [
          440.0,
          880.0
        ]
      }
    ]
  }
}