{"abstract":"The companded output omits wire complement.","category":"PCM sample encoding","checks":8,"contract":"Bounded mu-law-style selection model: clamp magnitude32635, add bias132, select segment and mantissa then complement the full eight-bit code.","contract_signature":"samples","evaluation_group":"s3-pcm-pcm-mulaw-code-selection","failed_approach":"Flipping only polarity leaves segment and mantissa coding inverted.","family":"s3-pcm-pcm-mulaw-code-selection-wire-complement","id":"FA-49861","implementations":{"attempt":{"sha256":"8badf8235cc32596cc1faf84a60f63e648ee803f01ed35f5999709108a143cae","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(samples):\n    out=[]\n    for sample in samples:\n        negative=sample<0\n        amplitude=min(32635,abs(sample))+132\n        exponent=0\n        while exponent<7 and amplitude>=(256<<exponent):\n            exponent+=1\n        mantissa=(amplitude>>(exponent+3))&15\n        code=(128 if negative else 0)|(exponent<<4)|mantissa\n        out.append(code^128)\n    return out\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('oracle 1', solve(*([0, 1, -1, 100, -100],)), [255, 255, 127, 242, 114])\ncheck('oracle 2', solve(*([124, 125, -124],)), [239, 239, 111])\ncheck('oracle 3', solve(*([32635, 40000, -40000],)), [128, 128, 0])\ncheck('oracle 4', solve(*([],)), [])\ncheck('oracle 5', solve(*([1000, 4000, 16000],)), [206, 175, 144])\ncheck('oracle 6', solve(*([380, 892, 1916],)), [223, 207, 191])\ncheck('oracle 7', solve(*([-1000, -4000, -16000],)), [78, 47, 16])\nif N == 1: check('variant packet 1', solve(*[[0, 1, -1, 100, -100, 0, 1, -1, 100, -100]]), [255, 255, 127, 242, 114, 255, 255, 127, 242, 114])\nif N == 2: check('variant packet 2', solve(*[[0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100]]), [255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114])\nif N == 3: check('variant packet 3', solve(*[[0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100]]), [255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114])\nif N == 4: check('variant packet 4', solve(*[[0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100]]), [255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114])\nif N == 5: check('variant packet 5', solve(*[[0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100]]), [255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114])\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":"368ebce3bfeb4fc71c8a002fa738c3b2463793470c7db4400d369ea2e2d12e0f","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(samples):\n    out=[]\n    for sample in samples:\n        negative=sample<0\n        amplitude=min(32635,abs(sample))+132\n        exponent=0\n        while exponent<7 and amplitude>=(256<<exponent):\n            exponent+=1\n        mantissa=(amplitude>>(exponent+3))&15\n        code=(128 if negative else 0)|(exponent<<4)|mantissa\n        out.append(code)\n    return out\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('oracle 1', solve(*([0, 1, -1, 100, -100],)), [255, 255, 127, 242, 114])\ncheck('oracle 2', solve(*([124, 125, -124],)), [239, 239, 111])\ncheck('oracle 3', solve(*([32635, 40000, -40000],)), [128, 128, 0])\ncheck('oracle 4', solve(*([],)), [])\ncheck('oracle 5', solve(*([1000, 4000, 16000],)), [206, 175, 144])\ncheck('oracle 6', solve(*([380, 892, 1916],)), [223, 207, 191])\ncheck('oracle 7', solve(*([-1000, -4000, -16000],)), [78, 47, 16])\nif N == 1: check('variant packet 1', solve(*[[0, 1, -1, 100, -100, 0, 1, -1, 100, -100]]), [255, 255, 127, 242, 114, 255, 255, 127, 242, 114])\nif N == 2: check('variant packet 2', solve(*[[0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100]]), [255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114])\nif N == 3: check('variant packet 3', solve(*[[0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100]]), [255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114])\nif N == 4: check('variant packet 4', solve(*[[0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100]]), [255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114])\nif N == 5: check('variant packet 5', solve(*[[0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100, 0, 1, -1, 100, -100]]), [255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114, 255, 255, 127, 242, 114])\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-pcm-mulaw-code-selection-wire-complement","generated_at":"2026-09-29T14:45:03.794895+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":"The companded output omits wire complement.","sha256":"da3c362c163a0bbc05b38ce1237ae14f143f3de9222c9aae07c15dab94a8fe6f","title":"Pcm mulaw code selection: wire complement · 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":42.066,"exit_code":1,"observations":[{"actual":[128,128,0,141,13],"check":"oracle 1","expected":[255,255,127,242,114],"passed":false},{"actual":[144,144,16],"check":"oracle 2","expected":[239,239,111],"passed":false},{"actual":[255,255,127],"check":"oracle 3","expected":[128,128,0],"passed":false},{"actual":[],"check":"oracle 4","expected":[],"passed":true},{"actual":[177,208,239],"check":"oracle 5","expected":[206,175,144],"passed":false},{"actual":[160,176,192],"check":"oracle 6","expected":[223,207,191],"passed":false},{"actual":[49,80,111],"check":"oracle 7","expected":[78,47,16],"passed":false},{"actual":[128,128,0,141,13,128,128,0,141,13],"check":"variant packet 1","expected":[255,255,127,242,114,255,255,127,242,114],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oracle 1\", \"actual\": [128, 128, 0, 141, 13], \"expected\": [255, 255, 127, 242, 114], \"passed\": false}, {\"check\": \"oracle 2\", \"actual\": [144, 144, 16], \"expected\": [239, 239, 111], \"passed\": false}, {\"check\": \"oracle 3\", \"actual\": [255, 255, 127], \"expected\": [128, 128, 0], \"passed\": false}, {\"check\": \"oracle 4\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"oracle 5\", \"actual\": [177, 208, 239], \"expected\": [206, 175, 144], \"passed\": false}, {\"check\": \"oracle 6\", \"actual\": [160, 176, 192], \"expected\": [223, 207, 191], \"passed\": false}, {\"check\": \"oracle 7\", \"actual\": [49, 80, 111], \"expected\": [78, 47, 16], \"passed\": false}, {\"check\": \"variant packet 1\", \"actual\": [128, 128, 0, 141, 13, 128, 128, 0, 141, 13], \"expected\": [255, 255, 127, 242, 114, 255, 255, 127, 242, 114], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.688,"exit_code":1,"observations":[{"actual":[0,0,128,13,141],"check":"oracle 1","expected":[255,255,127,242,114],"passed":false},{"actual":[16,16,144],"check":"oracle 2","expected":[239,239,111],"passed":false},{"actual":[127,127,255],"check":"oracle 3","expected":[128,128,0],"passed":false},{"actual":[],"check":"oracle 4","expected":[],"passed":true},{"actual":[49,80,111],"check":"oracle 5","expected":[206,175,144],"passed":false},{"actual":[32,48,64],"check":"oracle 6","expected":[223,207,191],"passed":false},{"actual":[177,208,239],"check":"oracle 7","expected":[78,47,16],"passed":false},{"actual":[0,0,128,13,141,0,0,128,13,141],"check":"variant packet 1","expected":[255,255,127,242,114,255,255,127,242,114],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oracle 1\", \"actual\": [0, 0, 128, 13, 141], \"expected\": [255, 255, 127, 242, 114], \"passed\": false}, {\"check\": \"oracle 2\", \"actual\": [16, 16, 144], \"expected\": [239, 239, 111], \"passed\": false}, {\"check\": \"oracle 3\", \"actual\": [127, 127, 255], \"expected\": [128, 128, 0], \"passed\": false}, {\"check\": \"oracle 4\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"oracle 5\", \"actual\": [49, 80, 111], \"expected\": [206, 175, 144], \"passed\": false}, {\"check\": \"oracle 6\", \"actual\": [32, 48, 64], \"expected\": [223, 207, 191], \"passed\": false}, {\"check\": \"oracle 7\", \"actual\": [177, 208, 239], \"expected\": [78, 47, 16], \"passed\": false}, {\"check\": \"variant packet 1\", \"actual\": [0, 0, 128, 13, 141, 0, 0, 128, 13, 141], \"expected\": [255, 255, 127, 242, 114, 255, 255, 127, 242, 114], \"passed\": false}], \"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."}}