Brief — audio-match

case:audio-match
TL;DR

Verdict: the low-bitrate 'query-reupload.mp3' is the SAME underlying recording as reference ref-sample-audio.m4a, aligned at +5.99s with 723 votes and a 361.5x margin — confirmed exact copy despite 32kbps transcode + volume change. Unrelated audio returns no match; speed-tampered copies collapse in margin/span and a 12% speedup is rejected outright by --min-margin 2.

Lines of investigation

TARGET

re-upload provenance: query-reupload.mp3 ANSWERED ▁▁▁▁▁▁█ 7d

? Is the low-bitrate clip query-reupload.mp3 the SAME underlying recording as one of the three reference tracks — and if so, at what time offset?

Discrimination checks: unrelated control clip -> no confident match (best rejected alignment: 2 votes, margin 2.0, span 1.0s). A 6% sped-up copy degraded to margin 11.8x with the aligned span collapsing 9.57s -> 2.18s (time-stretch drift); a 12% sped-up copy fell to margin 1.39x and was REJECTED by --min-margin 2. Wang-2003 fingerprints are robust to transcode/noise, NOT to pitch/speed change.

findings (1 accepted · 1 open):

  • rec_d2dcb4ced758bd9b [accepted] (high) Audio fingerprint matched ref-sample-audio.m4a (361.5× margin) in query-reupload.mp3
    case:audio-match/.overcast/media/audio-matches/match_d4d48534fb81867f.svg
  • rec_0cd080ff5d7d4fe8 [open] (high) Speed-tamper signature: a 6% sped-up re-encode of the same recording still aligns at +6.18s but the margin collapses 361.5x -> 11.8x and the aligned span shrinks 9.57s -> 2.18s (time-stretch drift breaks Wang-2003 alignment); at 12% speedup the margin falls to 1.39x and --min-margin 2 rejects it outright.
    case:audio-match/.overcast/media/audio-matches/match_81f9dd53f16c9aa5.svg

scan 0 → capture 0 → sense 0 → match 0 · last activity 8s ago

closed: Yes — query-reupload.mp3 is ref-sample-audio.m4a at offset +5.99s (723 aligned votes, 361.5x margin); finding rec_d2dcb4ced758bd9b accepted.

Coverage

none — no scan hits in scope

Other findings

none — every finding is linked to a line above

MODEbrief
RECORDS12
audio 7finding 2note 3
#1audiorec_e73d7d81446f700ereadyshowcase/audio-match/media/ref-sample-audio.m4a
fingerprinted ref-sample-audio.m4a into local_audio_fp_5228907a (12490 hashes, 20.0s)
record details
{
  "payload": {
    "op": "add",
    "index": "local_audio_fp_5228907a",
    "file": "showcase/audio-match/media/ref-sample-audio.m4a",
    "hashes": 12490,
    "duration_seconds": 20.02,
    "summary": "fingerprinted ref-sample-audio.m4a into local_audio_fp_5228907a (12490 hashes, 20.0s)"
  },
  "meta": {
    "time": "2026-07-13T01:27:24.298Z",
    "provider": "local:audio-fp",
    "model": "wang2003",
    "case": "case:audio-match"
  },
  "media": {
    "ref": "showcase/audio-match/media/ref-sample-audio.m4a"
  }
}
#2audiorec_1d019053d2406388readyshowcase/audio-match/media/ref-speech.m4a
fingerprinted ref-speech.m4a into local_audio_fp_5228907a (26114 hashes, 40.0s)
record details
{
  "payload": {
    "op": "add",
    "index": "local_audio_fp_5228907a",
    "file": "showcase/audio-match/media/ref-speech.m4a",
    "hashes": 26114,
    "duration_seconds": 40.01,
    "summary": "fingerprinted ref-speech.m4a into local_audio_fp_5228907a (26114 hashes, 40.0s)"
  },
  "meta": {
    "time": "2026-07-13T01:27:25.080Z",
    "provider": "local:audio-fp",
    "model": "wang2003",
    "case": "case:audio-match"
  },
  "media": {
    "ref": "showcase/audio-match/media/ref-speech.m4a"
  }
}
#3audiorec_8ffc78e24117c07creadyshowcase/audio-match/media/ref-bbq.m4a
fingerprinted ref-bbq.m4a into local_audio_fp_5228907a (19553 hashes, 40.0s)
record details
{
  "payload": {
    "op": "add",
    "index": "local_audio_fp_5228907a",
    "file": "showcase/audio-match/media/ref-bbq.m4a",
    "hashes": 19553,
    "duration_seconds": 40.01,
    "summary": "fingerprinted ref-bbq.m4a into local_audio_fp_5228907a (19553 hashes, 40.0s)"
  },
  "meta": {
    "time": "2026-07-13T01:27:25.859Z",
    "provider": "local:audio-fp",
    "model": "wang2003",
    "case": "case:audio-match"
  },
  "media": {
    "ref": "showcase/audio-match/media/ref-bbq.m4a"
  }
}
#4audiorec_8952e809fa5cc231readyshowcase/audio-match/media/query-reupload.mp3
query matches ref-sample-audio.m4a at 5.99s (723 aligned votes)
record details
{
  "payload": {
    "op": "match",
    "summary": "query matches ref-sample-audio.m4a at 5.99s (723 aligned votes)",
    "matches": [
      {
        "ref": "showcase/audio-match/media/ref-sample-audio.m4a",
        "duration_seconds": 20.02,
        "offset_seconds": 5.99,
        "aligned_votes": 723,
        "total_query_hashes": 5879,
        "match_ratio": 0.123,
        "margin": 361.5,
        "span_seconds": 9.57,
        "match_draw_path": "case:audio-match/.overcast/media/audio-matches/match_d4d48534fb81867f.svg"
      }
    ],
    "count": 1,
    "query": {
      "duration_seconds": 11,
      "n_hashes": 5879
    },
    "fingerprint": {
      "sample_rate": 11025,
      "n_fft": 2048,
      "hop": 512,
      "fan_out": 15
    },
    "index": "local_audio_fp_5228907a"
  },
  "meta": {
    "time": "2026-07-13T01:27:37.676Z",
    "provider": "local:audio-fp",
    "model": "wang2003",
    "case": "case:audio-match"
  },
  "media": {
    "ref": "showcase/audio-match/media/query-reupload.mp3"
  }
}
#5findingrec_d2dcb4ced758bd9breadyshowcase/audio-match/media/query-reupload.mp3
Audio fingerprint matched ref-sample-audio.m4a (361.5× margin) in query-reupload.mp3
record details
{
  "payload": {
    "text": "Audio fingerprint matched ref-sample-audio.m4a (361.5× margin) in query-reupload.mp3",
    "target": "",
    "source_record": "rec_8952e809fa5cc231",
    "source_verb": "audio",
    "trigger": "signal:audio-match",
    "status": "suggested",
    "confidence": "high",
    "signal": {
      "kind": "audio-match",
      "score": 361.5,
      "threshold": 1,
      "unit": "margin",
      "matched": "showcase/audio-match/media/ref-sample-audio.m4a"
    }
  },
  "meta": {
    "time": "2026-07-13T01:27:37.677Z",
    "case": "case:audio-match",
    "provider": "automation"
  },
  "media": {
    "ref": "showcase/audio-match/media/query-reupload.mp3"
  }
}
#6audiorec_3953e8dff2560dc1readyshowcase/audio-match/media/control-unrelated.m4a
no confident audio match
record details
{
  "payload": {
    "op": "match",
    "summary": "no confident audio match",
    "matches": [],
    "count": 0,
    "query": {
      "duration_seconds": 15.02,
      "n_hashes": 6053
    },
    "fingerprint": {
      "sample_rate": 11025,
      "n_fft": 2048,
      "hop": 512,
      "fan_out": 15
    },
    "index": "local_audio_fp_5228907a",
    "best_rejected": {
      "ref": "showcase/audio-match/media/ref-speech.m4a",
      "duration_seconds": 40.01,
      "offset_seconds": 18.76,
      "aligned_votes": 2,
      "total_query_hashes": 6053,
      "match_ratio": 0.0003,
      "margin": 2,
      "span_seconds": 1.02,
      "match_draw_path": "case:audio-match/.overcast/media/audio-matches/match_c8444609d20e07fd.svg"
    }
  },
  "meta": {
    "time": "2026-07-13T01:27:59.963Z",
    "provider": "local:audio-fp",
    "model": "wang2003",
    "case": "case:audio-match"
  },
  "media": {
    "ref": "showcase/audio-match/media/control-unrelated.m4a"
  }
}
#7audiorec_d21dd46bfb6ba7b8readyshowcase/audio-match/media/query-spedup.mp3
query matches ref-sample-audio.m4a at 6.18s (400 aligned votes)
record details
{
  "payload": {
    "op": "match",
    "summary": "query matches ref-sample-audio.m4a at 6.18s (400 aligned votes)",
    "matches": [
      {
        "ref": "showcase/audio-match/media/ref-sample-audio.m4a",
        "duration_seconds": 20.02,
        "offset_seconds": 6.18,
        "aligned_votes": 400,
        "total_query_hashes": 5478,
        "match_ratio": 0.073,
        "margin": 11.76,
        "span_seconds": 2.18,
        "match_draw_path": "case:audio-match/.overcast/media/audio-matches/match_81f9dd53f16c9aa5.svg"
      }
    ],
    "count": 1,
    "query": {
      "duration_seconds": 10.38,
      "n_hashes": 5478
    },
    "fingerprint": {
      "sample_rate": 11025,
      "n_fft": 2048,
      "hop": 512,
      "fan_out": 15
    },
    "index": "local_audio_fp_5228907a"
  },
  "meta": {
    "time": "2026-07-13T01:28:10.278Z",
    "provider": "local:audio-fp",
    "model": "wang2003",
    "case": "case:audio-match"
  },
  "media": {
    "ref": "showcase/audio-match/media/query-spedup.mp3"
  }
}
#8audiorec_c27b0f3d01745bd4readyshowcase/audio-match/media/query-spedup12.mp3
no confident audio match
record details
{
  "payload": {
    "op": "match",
    "summary": "no confident audio match",
    "matches": [],
    "count": 0,
    "query": {
      "duration_seconds": 9.82,
      "n_hashes": 5314
    },
    "fingerprint": {
      "sample_rate": 11025,
      "n_fft": 2048,
      "hop": 512,
      "fan_out": 15
    },
    "index": "local_audio_fp_5228907a",
    "best_rejected": {
      "ref": "showcase/audio-match/media/ref-sample-audio.m4a",
      "duration_seconds": 20.02,
      "offset_seconds": 6.41,
      "aligned_votes": 71,
      "total_query_hashes": 5314,
      "match_ratio": 0.0134,
      "margin": 1.39,
      "span_seconds": 1.16,
      "match_draw_path": "case:audio-match/.overcast/media/audio-matches/match_2aae0fe86ad8e27a.svg"
    }
  },
  "meta": {
    "time": "2026-07-13T01:28:42.384Z",
    "provider": "local:audio-fp",
    "model": "wang2003",
    "case": "case:audio-match"
  },
  "media": {
    "ref": "showcase/audio-match/media/query-spedup12.mp3"
  }
}
#9noterec_fc5aeb7373d37d4ereadyshowcase/audio-match/media/query-reupload.mp3
query-reupload.mp3 IS ref-sample-audio.m4a: 723 hash votes align at offset +5.99s (ground truth: the slice was cut at +6.00s), margin 361.5x over the runner-up offset, aligned span 9.57s of an 11s query — an exact-recording match that survived 32kbps re-encode and a volume change.
record details
{
  "payload": {
    "text": "query-reupload.mp3 IS ref-sample-audio.m4a: 723 hash votes align at offset +5.99s (ground truth: the slice was cut at +6.00s), margin 361.5x over the runner-up offset, aligned span 9.57s of an 11s query — an exact-recording match that survived 32kbps re-encode and a volume change.",
    "tags": [
      "thread:tgt_5c64e4",
      "provenance"
    ],
    "confidence": "high",
    "ref": "showcase/audio-match/media/query-reupload.mp3",
    "related_record": "rec_8952e809fa5cc231"
  },
  "meta": {
    "time": "2026-07-13T01:29:37.609Z",
    "provider": "human",
    "case": "case:audio-match"
  },
  "media": {
    "ref": "showcase/audio-match/media/query-reupload.mp3"
  }
}
#10noterec_ae605ff08381169creadyshowcase/audio-match/media/query-spedup12.mp3
Discrimination checks: unrelated control clip -> no confident match (best rejected alignment: 2 votes, margin 2.0, span 1.0s). A 6% sped-up copy degraded to margin 11.8x with the aligned span collapsing 9.57s -> 2.18s (time-stretch drift); a 12% sped-up copy fell to margin 1.39x and was REJECTED by --min-margin 2. Wang-2003 fingerprints are robust to transcode/noise, NOT to pitch/speed change.
record details
{
  "payload": {
    "text": "Discrimination checks: unrelated control clip -> no confident match (best rejected alignment: 2 votes, margin 2.0, span 1.0s). A 6% sped-up copy degraded to margin 11.8x with the aligned span collapsing 9.57s -> 2.18s (time-stretch drift); a 12% sped-up copy fell to margin 1.39x and was REJECTED by --min-margin 2. Wang-2003 fingerprints are robust to transcode/noise, NOT to pitch/speed change.",
    "tags": [
      "thread:tgt_5c64e4",
      "caveat"
    ],
    "confidence": "high",
    "ref": "showcase/audio-match/media/query-spedup12.mp3",
    "related_record": "rec_c27b0f3d01745bd4"
  },
  "meta": {
    "time": "2026-07-13T01:29:37.973Z",
    "provider": "human",
    "case": "case:audio-match"
  },
  "media": {
    "ref": "showcase/audio-match/media/query-spedup12.mp3"
  }
}
#11noterec_a2c1c2e190c49f44ready
Verdict: the low-bitrate 'query-reupload.mp3' is the SAME underlying recording as reference ref-sample-audio.m4a, aligned at +5.99s with 723 votes and a 361.5x margin — confirmed exact copy despite 32kbps transcode + volume change. Unrelated audio returns no match; speed-tampered copies collapse in margin/span and a 12% speedup is rejected outright by --min-margin 2.
record details
{
  "payload": {
    "text": "Verdict: the low-bitrate 'query-reupload.mp3' is the SAME underlying recording as reference ref-sample-audio.m4a, aligned at +5.99s with 723 votes and a 361.5x margin — confirmed exact copy despite 32kbps transcode + volume change. Unrelated audio returns no match; speed-tampered copies collapse in margin/span and a 12% speedup is rejected outright by --min-margin 2.",
    "tags": [
      "tldr"
    ],
    "confidence": "high"
  },
  "meta": {
    "time": "2026-07-13T01:29:38.327Z",
    "provider": "human",
    "case": "case:audio-match"
  },
  "media": null
}
#12findingrec_0cd080ff5d7d4fe8readyshowcase/audio-match/media/query-spedup.mp3
Speed-tamper signature: a 6% sped-up re-encode of the same recording still aligns at +6.18s but the margin collapses 361.5x -> 11.8x and the aligned span shrinks 9.57s -> 2.18s (time-stretch drift breaks Wang-2003 alignment); at 12% speedup the margin falls to 1.39x and --min-margin 2 rejects it outright.
record details
{
  "payload": {
    "text": "Speed-tamper signature: a 6% sped-up re-encode of the same recording still aligns at +6.18s but the margin collapses 361.5x -> 11.8x and the aligned span shrinks 9.57s -> 2.18s (time-stretch drift breaks Wang-2003 alignment); at 12% speedup the margin falls to 1.39x and --min-margin 2 rejects it outright.",
    "target": "re-upload provenance: query-reupload.mp3",
    "source_record": "rec_d21dd46bfb6ba7b8",
    "source_verb": "audio",
    "trigger": "human",
    "status": "open",
    "target_id": "tgt_5c64e4",
    "confidence": "high",
    "ref": "showcase/audio-match/media/query-spedup.mp3"
  },
  "meta": {
    "time": "2026-07-13T01:31:11.329Z",
    "case": "case:audio-match",
    "provider": "human"
  },
  "media": {
    "ref": "showcase/audio-match/media/query-spedup.mp3"
  }
}