Source

Name	Type	Description
integrated_lufs	number	LUFS = Loudness Units Full Scale. The Integrated value means the loudness integrated over the entire length of the program. European TV applications have a recommended level of -23 LUFS. Web services like iTunes and YouTube have targets of -16 and -14 respectively.
loudness_lra_lufs	number	LRA = Loudness Range. This quantifies the statistical distribution of short-term loudness within a program. A low LRA (-1 to -3) indicates material with a narrow dynamic range.
true_peak_dbfs	number	True Peak indicates whether there is maximum intersample peaking.
integrated_threshold_lufs	number	Sets threshold value for integrated LUFS.
offset	number	DC offset.

---

Example source

{
  "uid": "transcode_media",
  "kind": "transcode",
  "payload": {
    "location": {
    },
    "targets": [
      {
        "file_pattern": "{source_basename}_converted.mp4",
        "container": {
          "kind": "mp4"
        },
        "video": {
        },
        "audio": [
          {
            "codec": "heaac_v2",
            "channels": 4,
            "sample_rate": 48000,
            "filters": [
              {
                "kind": "normalize",
                "payload": {
                  "kind": "ebur128",
                  "payload": {
                    "source": {
                      "integrated_lufs": -20,
                      "true_peak_dbfs": -1,
                    },
                    "integrated_lufs": -16,
                    "true_peak_dbfs": -3,
                    "allow_unprecise_mode": false
                  }
                }
              }
            ]
          }
        ]
      }
    ]
  }
}