{
  "date": "2026-11-05",
  "origin": "Original synthetic English speech from our locally generated control; original solid-color video. No private or third-party media.",
  "reference": "Please review these words before you share the transcript.",
  "encoding_commands": [
    [
      "ffmpeg",
      "-hide_banner",
      "-loglevel",
      "error",
      "-y",
      "-f",
      "lavfi",
      "-i",
      "color=c=0x153c35:s=320x180:r=24",
      "-i",
      "reference.wav",
      "-map",
      "0:v:0",
      "-map",
      "1:a:0",
      "-c:v",
      "libx264",
      "-preset",
      "veryfast",
      "-pix_fmt",
      "yuv420p",
      "-c:a",
      "aac",
      "-b:a",
      "64k",
      "-shortest",
      "aac-video.mp4"
    ],
    [
      "ffmpeg",
      "-hide_banner",
      "-loglevel",
      "error",
      "-y",
      "-f",
      "lavfi",
      "-i",
      "color=c=0x153c35:s=320x180:r=24",
      "-i",
      "reference.wav",
      "-map",
      "0:v:0",
      "-map",
      "1:a:0",
      "-c:v",
      "libx264",
      "-preset",
      "veryfast",
      "-pix_fmt",
      "yuv420p",
      "-c:a",
      "ac3",
      "-b:a",
      "96k",
      "-shortest",
      "ac3-video.mp4"
    ]
  ],
  "incomplete_control": "First floor(full AAC MP4 bytes / 2) bytes, deliberately truncated; not an alternative valid codec.",
  "fixtures": [
    {
      "file": "reference.wav",
      "bytes": 179698,
      "sha256": "e17aeeb9a534450e0bad95ceb032268b7118ea2be1a8f87ca1439bd2993e42ac",
      "ffprobe_command": [
        "ffprobe",
        "-v",
        "error",
        "-show_entries",
        "stream=codec_type,codec_name,sample_rate,channels:format=duration,format_name",
        "-of",
        "json",
        "reference.wav"
      ],
      "ffprobe_exit": 0,
      "ffprobe_stdout": {
        "programs": [],
        "stream_groups": [],
        "streams": [
          {
            "codec_name": "pcm_s16le",
            "codec_type": "audio",
            "sample_rate": "22050",
            "channels": 1
          }
        ],
        "format": {
          "format_name": "wav",
          "duration": "4.073741"
        }
      },
      "ffprobe_stderr": ""
    },
    {
      "file": "aac-video.mp4",
      "bytes": 33629,
      "sha256": "a7d90212fffcf9fd4bf945f85bc48468737044b447e133fecd903359c6addc4a",
      "ffprobe_command": [
        "ffprobe",
        "-v",
        "error",
        "-show_entries",
        "stream=codec_type,codec_name,sample_rate,channels:format=duration,format_name",
        "-of",
        "json",
        "aac-video.mp4"
      ],
      "ffprobe_exit": 0,
      "ffprobe_stdout": {
        "programs": [],
        "stream_groups": [],
        "streams": [
          {
            "codec_name": "h264",
            "codec_type": "video"
          },
          {
            "codec_name": "aac",
            "codec_type": "audio",
            "sample_rate": "22050",
            "channels": 1
          }
        ],
        "format": {
          "format_name": "mov,mp4,m4a,3gp,3g2,mj2",
          "duration": "4.073741"
        }
      },
      "ffprobe_stderr": ""
    },
    {
      "file": "ac3-video.mp4",
      "bytes": 54996,
      "sha256": "33e675b03667b39c014aed5ce23db10f9ce495c37e01755f178f184f712adced",
      "ffprobe_command": [
        "ffprobe",
        "-v",
        "error",
        "-show_entries",
        "stream=codec_type,codec_name,sample_rate,channels:format=duration,format_name",
        "-of",
        "json",
        "ac3-video.mp4"
      ],
      "ffprobe_exit": 0,
      "ffprobe_stdout": {
        "programs": [],
        "stream_groups": [],
        "streams": [
          {
            "codec_name": "h264",
            "codec_type": "video"
          },
          {
            "codec_name": "ac3",
            "codec_type": "audio",
            "sample_rate": "32000",
            "channels": 1,
            "side_data_list": [
              {}
            ]
          }
        ],
        "format": {
          "format_name": "mov,mp4,m4a,3gp,3g2,mj2",
          "duration": "4.625000"
        }
      },
      "ffprobe_stderr": ""
    },
    {
      "file": "incomplete-video.mp4",
      "bytes": 16814,
      "sha256": "bc7d91a0fcd8fb065a766accaf00b63870ee96d43be81a913403ab8588129eb5",
      "ffprobe_command": [
        "ffprobe",
        "-v",
        "error",
        "-show_entries",
        "stream=codec_type,codec_name,sample_rate,channels:format=duration,format_name",
        "-of",
        "json",
        "incomplete-video.mp4"
      ],
      "ffprobe_exit": 1,
      "ffprobe_stdout": {},
      "ffprobe_stderr": "[mov,mp4,m4a,3gp,3g2,mj2 @ 000001fd8dacca40] moov atom not found\nincomplete-video.mp4: Invalid data found when processing input"
    }
  ]
}