{
  "schema": 1,
  "spec": "openstream",
  "specVersion": "NXS1",
  "generatedAt": "2026-09-12T13:13:15.713Z",
  "implementation": {
    "name": "nixamp",
    "version": "0.17.1"
  },
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    "zlib": "12731092979c6d07f42da27da673a9f6c7b13586",
    "os": "linux 7.0.0-30-generic",
    "arch": "x64",
    "cpu": "DO-Premium-Intel",
    "cores": 8,
    "memoryGiB": 15.6
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  "envelope": {
    "magic": "NXS1",
    "streamHeaderBytes": 16,
    "frameHeaderBytes": 48
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    "minSavingsBytes": 512,
    "maxBlockBytes": 262144,
    "zstdLevels": [
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  },
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          "note": "not a transport stream: ts-zstd does not apply"
        }
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        {
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          "encodeMs": 2.78,
          "decodeMs": 3.18,
          "roundTrip": true
        },
        {
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          "encodeMs": 0,
          "decodeMs": 0,
          "roundTrip": false,
          "note": "not a transport stream: ts-zstd does not apply"
        }
      ],
      "recommendation": {
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        "reason": "saves 99.95% of the complete wire size"
      }
    },
    {
      "sample": "ts-padded-50pct",
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      "sha256": "fbbe8a14abcd5d36e40ccf8d5d80eca805580cccd632842a4f1cea9461863a6d",
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        {
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      ],
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        "reason": "saves 50.09% of the complete wire size"
      }
    },
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          "decodeMs": 0,
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        {
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        {
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          "decodeMs": 0,
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      ],
      "recommendation": {
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        "level": 0,
        "reason": "no codec beat stored by the configured margin"
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    },
    {
      "sample": "tiny-3b",
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        {
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        },
        {
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          "note": "not a transport stream: ts-zstd does not apply"
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      ],
      "recommendation": {
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        "level": 0,
        "reason": "no codec beat stored by the configured margin"
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    },
    {
      "sample": "empty",
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      "inputBytes": 0,
      "sha256": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
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      "rows": [
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        {
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        {
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        {
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        {
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        },
        {
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      ],
      "recommendation": {
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        "reason": "no codec beat stored by the configured margin"
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    }
  ],
  "summary": {
    "corpusBytes": 4649731,
    "byMode": [
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        "level": 0,
        "wireBytes": 4651091,
        "savingsPercent": -0.03,
        "roundTrip": true,
        "encodeMs": 0,
        "decodeMs": 0
      },
      {
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        "savingsPercent": 52.91,
        "roundTrip": true,
        "encodeMs": 96.34,
        "decodeMs": 13.78
      },
      {
        "mode": "zstd",
        "level": 1,
        "wireBytes": 2180200,
        "savingsPercent": 53.11,
        "roundTrip": true,
        "encodeMs": 18.84,
        "decodeMs": 23.12
      },
      {
        "mode": "zstd",
        "level": 3,
        "wireBytes": 2177968,
        "savingsPercent": 53.16,
        "roundTrip": true,
        "encodeMs": 24.23,
        "decodeMs": 11.67
      },
      {
        "mode": "zstd",
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        "wireBytes": 2177476,
        "savingsPercent": 53.17,
        "roundTrip": true,
        "encodeMs": 53.51,
        "decodeMs": 13.5
      },
      {
        "mode": "ts-zstd",
        "level": 1,
        "wireBytes": 1127961,
        "savingsPercent": 25,
        "roundTrip": true,
        "encodeMs": 15.4,
        "decodeMs": 9.8
      }
    ]
  },
  "caveats": [
    "Envelope v1: a 16-byte stream header, a 48-byte header per frame, plus one end frame.",
    "OpenStream is a framing envelope over Zstandard and gzip, not a new compression algorithm; these numbers are those codecs at the block boundary, honestly framed.",
    "Synthetic samples do not predict production savings. A padded transport stream flatters a codec by its padding; an efficient real feed saves far less. Use --corpus with authorized real samples for numbers that mean something.",
    "Timings are wall-clock on the machine and runtime named in `environment` and do not transfer to other hardware.",
    "roundTrip:false in any row is a failure of exactness and must block a release."
  ]
}