{"abstract":"Segment extraction includes a mantissa bit.","category":"PCM sample encoding","checks":8,"contract":"Decode eight-bit mu-law codewords using complement, three-bit segment, four-bit mantissa and reconstruction bias132; return signed integer PCM amplitudes.","contract_signature":"codes","evaluation_group":"s3-pcm-mulaw-expansion","failed_approach":"Widening the segment field includes polarity as exponent.","family":"s3-pcm-mulaw-expansion-segment-field","id":"FA-48986","implementations":{"attempt":{"sha256":"80ddb5e078611aaf213902fbef0498259c230c79f76ae09a733d82177670e430","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(codes):\n    out=[]\n    for raw in codes:\n        code=(~raw)&255\n        mantissa=code&15\n        exponent=(code>>4)&15\n        amplitude=((mantissa<<3)+132)<<exponent\n        amplitude-=132\n        out.append(-amplitude if code&128 else amplitude)\n    return out\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('oracle 1', solve(*([255, 127, 0, 128],)), [0, 0, -32124, 32124])\ncheck('oracle 2', solve(*([254, 253, 252],)), [8, 16, 24])\ncheck('oracle 3', solve(*([240, 239, 224],)), [120, 132, 372])\ncheck('oracle 4', solve(*([16, 32, 64],)), [-15996, -7932, -1884])\ncheck('oracle 5', solve(*([],)), [])\ncheck('oracle 6', solve(*([175, 191, 207, 223],)), [4092, 1980, 924, 396])\ncheck('oracle 7', solve(*([1, 2, 126],)), [-31100, -30076, -8])\nif N == 1: check('variant packet 1', solve(*[[255, 127, 0, 128, 255, 127, 0, 128]]), [0, 0, -32124, 32124, 0, 0, -32124, 32124])\nif N == 2: check('variant packet 2', solve(*[[255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128]]), [0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124])\nif N == 3: check('variant packet 3', solve(*[[255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128]]), [0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124])\nif N == 4: check('variant packet 4', solve(*[[255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128]]), [0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124])\nif N == 5: check('variant packet 5', solve(*[[255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128]]), [0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"383b350beaa6296fd71fcd51bd13f68cdb078a181df84b92676ea32fce633fc4","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(codes):\n    out=[]\n    for raw in codes:\n        code=(~raw)&255\n        mantissa=code&15\n        exponent=(code>>3)&7\n        amplitude=((mantissa<<3)+132)<<exponent\n        amplitude-=132\n        out.append(-amplitude if code&128 else amplitude)\n    return out\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('oracle 1', solve(*([255, 127, 0, 128],)), [0, 0, -32124, 32124])\ncheck('oracle 2', solve(*([254, 253, 252],)), [8, 16, 24])\ncheck('oracle 3', solve(*([240, 239, 224],)), [120, 132, 372])\ncheck('oracle 4', solve(*([16, 32, 64],)), [-15996, -7932, -1884])\ncheck('oracle 5', solve(*([],)), [])\ncheck('oracle 6', solve(*([175, 191, 207, 223],)), [4092, 1980, 924, 396])\ncheck('oracle 7', solve(*([1, 2, 126],)), [-31100, -30076, -8])\nif N == 1: check('variant packet 1', solve(*[[255, 127, 0, 128, 255, 127, 0, 128]]), [0, 0, -32124, 32124, 0, 0, -32124, 32124])\nif N == 2: check('variant packet 2', solve(*[[255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128]]), [0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124])\nif N == 3: check('variant packet 3', solve(*[[255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128]]), [0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124])\nif N == 4: check('variant packet 4', solve(*[[255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128]]), [0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124])\nif N == 5: check('variant packet 5', solve(*[[255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128, 255, 127, 0, 128]]), [0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124, 0, 0, -32124, 32124])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":"Stipulated finite model; no claim of hardware timing or full file-format conformance. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"s3-pcm-mulaw-expansion-segment-field","generated_at":"2026-09-29T14:44:55.696318+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Offline PCM interchange uses these exact bounded packet and sample representation decisions.","root_cause":"Segment extraction includes a mantissa bit.","sha256":"41a422b0ed91f88d7957f7b1d128d3048f9ef893b15485b202c1e9d2972bfeb4","title":"Mulaw expansion: segment field · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":41.128,"exit_code":1,"observations":[{"actual":[0,-33660,-8257404,32124],"check":"oracle 1","expected":[0,0,-32124,32124],"passed":false},{"actual":[8,16,24],"check":"oracle 2","expected":[8,16,24],"passed":true},{"actual":[120,132,372],"check":"oracle 3","expected":[120,132,372],"passed":true},{"actual":[-4128636,-2064252,-515964],"check":"oracle 4","expected":[-15996,-7932,-1884],"passed":false},{"actual":[],"check":"oracle 5","expected":[],"passed":true},{"actual":[4092,1980,924,396],"check":"oracle 6","expected":[4092,1980,924,396],"passed":true},{"actual":[-7995260,-7733116,-35708],"check":"oracle 7","expected":[-31100,-30076,-8],"passed":false},{"actual":[0,-33660,-8257404,32124,0,-33660,-8257404,32124],"check":"variant packet 1","expected":[0,0,-32124,32124,0,0,-32124,32124],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oracle 1\", \"actual\": [0, -33660, -8257404, 32124], \"expected\": [0, 0, -32124, 32124], \"passed\": false}, {\"check\": \"oracle 2\", \"actual\": [8, 16, 24], \"expected\": [8, 16, 24], \"passed\": true}, {\"check\": \"oracle 3\", \"actual\": [120, 132, 372], \"expected\": [120, 132, 372], \"passed\": true}, {\"check\": \"oracle 4\", \"actual\": [-4128636, -2064252, -515964], \"expected\": [-15996, -7932, -1884], \"passed\": false}, {\"check\": \"oracle 5\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"oracle 6\", \"actual\": [4092, 1980, 924, 396], \"expected\": [4092, 1980, 924, 396], \"passed\": true}, {\"check\": \"oracle 7\", \"actual\": [-7995260, -7733116, -35708], \"expected\": [-31100, -30076, -8], \"passed\": false}, {\"check\": \"variant packet 1\", \"actual\": [0, -33660, -8257404, 32124, 0, -33660, -8257404, 32124], \"expected\": [0, 0, -32124, 32124, 0, 0, -32124, 32124], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":40.048,"exit_code":1,"observations":[{"actual":[0,0,-32124,32124],"check":"oracle 1","expected":[0,0,-32124,32124],"passed":true},{"actual":[8,16,24],"check":"oracle 2","expected":[8,16,24],"passed":true},{"actual":[372,396,1884],"check":"oracle 3","expected":[120,132,372],"passed":false},{"actual":[-7932,-1884,-32124],"check":"oracle 4","expected":[-15996,-7932,-1884],"passed":false},{"actual":[],"check":"oracle 5","expected":[],"passed":true},{"actual":[396,0,8316,1980],"check":"oracle 6","expected":[4092,1980,924,396],"passed":false},{"actual":[-31100,-30076,-8],"check":"oracle 7","expected":[-31100,-30076,-8],"passed":true},{"actual":[0,0,-32124,32124,0,0,-32124,32124],"check":"variant packet 1","expected":[0,0,-32124,32124,0,0,-32124,32124],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oracle 1\", \"actual\": [0, 0, -32124, 32124], \"expected\": [0, 0, -32124, 32124], \"passed\": true}, {\"check\": \"oracle 2\", \"actual\": [8, 16, 24], \"expected\": [8, 16, 24], \"passed\": true}, {\"check\": \"oracle 3\", \"actual\": [372, 396, 1884], \"expected\": [120, 132, 372], \"passed\": false}, {\"check\": \"oracle 4\", \"actual\": [-7932, -1884, -32124], \"expected\": [-15996, -7932, -1884], \"passed\": false}, {\"check\": \"oracle 5\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"oracle 6\", \"actual\": [396, 0, 8316, 1980], \"expected\": [4092, 1980, 924, 396], \"passed\": false}, {\"check\": \"oracle 7\", \"actual\": [-31100, -30076, -8], \"expected\": [-31100, -30076, -8], \"passed\": true}, {\"check\": \"variant packet 1\", \"actual\": [0, 0, -32124, 32124, 0, 0, -32124, 32124], \"expected\": [0, 0, -32124, 32124, 0, 0, -32124, 32124], \"passed\": true}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}