{"abstract":"Receivers decode hours as frames.","category":"Broadcast timecode arithmetic","checks":9,"contract":"Pack HH:MM:SS:FF into four bytes [frames, seconds, minutes, hours] in transmission order. Each byte holds units in bits 0-3 and tens from bit 4 upward. The frames byte carries the drop-frame flag (bit 6, set when the last separator is \";\") and the color-frame flag (bit 7).","contract_signature":"tc, color","evaluation_group":"w2-broadcast-timecode-arithmetic-ltc-bcd-packing","failed_approach":"Swapping only seconds and minutes still misorders the frame.","family":"w2-broadcast-timecode-arithmetic-ltc-bcd-packing-transmission-order","id":"FA-78636","implementations":{"attempt":{"sha256":"cd344591a1a2be476256961f9b45b10f3133ebb140f22878223bf0d13dac60eb","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport re\nN = 1\nobservations = []\ndef solve(tc, color):\n    h,m,s,f=map(int,re.split('[:;]',tc))\n    drop=';' in tc\n    def bcd(v,flags):\n        return (v//10)<<4|v%10|flags\n    b0=bcd(f,(0x40 if drop else 0)|(0x80 if color else 0))\n    b1=bcd(s,0)\n    b2=bcd(m,0)\n    b3=bcd(h,0)\n    return [b0,b2,b1,b3]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[('regression: transmission order', ['23:59:59;29', True], [233, 89, 89, 35]), ('regression variant: transmission order', ['00:00:00:00', True], [128, 0, 0, 0]), ('partial repair probe: transmission order', ['10:10:09;24', False], [100, 9, 16, 16]), ('partial repair variant: transmission order', ['01:00:59;19', True], [217, 89, 0, 1]), ('boundary control', ['00:00:00:00', False], [0, 0, 0, 0]), ('boundary control', ['10:10:10:10', False], [16, 16, 16, 16]), ('normal control', ['00:59:59:00', False], [0, 89, 89, 0]), ('normal control', ['01:00:00:01', False], [1, 0, 0, 1]), ('normal control', ['19:10:10:19', False], [25, 16, 16, 25])], [('regression: transmission order', ['01:02:03;04', False], [68, 3, 2, 1]), ('regression variant: transmission order', ['19:00:09;19', True], [217, 9, 0, 25]), ('partial repair probe: transmission order', ['01:59:10:24', True], [164, 16, 89, 1]), ('partial repair variant: transmission order', ['10:07:59:01', False], [1, 89, 7, 16]), ('boundary control', ['10:10:10:10', False], [16, 16, 16, 16]), ('boundary control', ['00:00:00:00', False], [0, 0, 0, 0]), ('normal control', ['00:59:59:00', False], [0, 89, 89, 0]), ('normal control', ['01:00:00:01', False], [1, 0, 0, 1]), ('normal control', ['19:10:10:19', False], [25, 16, 16, 25])], [('regression: transmission order', ['01:07:10:29', True], [169, 16, 7, 1]), ('regression variant: transmission order', ['01:59:10:24', True], [164, 16, 89, 1]), ('partial repair probe: transmission order', ['00:07:09:29', True], [169, 9, 7, 0]), ('partial repair variant: transmission order', ['23:59:10:09', False], [9, 16, 89, 35]), ('boundary control', ['00:00:00:00', False], [0, 0, 0, 0]), ('boundary control', ['10:10:10:10', False], [16, 16, 16, 16]), ('normal control', ['19:10:10:19', False], [25, 16, 16, 25]), ('normal control', ['00:59:59:00', False], [0, 89, 89, 0]), ('normal control', ['01:00:00:01', False], [1, 0, 0, 1])], [('regression: transmission order', ['10:10:09;24', False], [100, 9, 16, 16]), ('regression variant: transmission order', ['00:07:09:29', True], [169, 9, 7, 0]), ('partial repair probe: transmission order', ['10:00:10;19', True], [217, 16, 0, 16]), ('partial repair variant: transmission order', ['10:00:10;09', False], [73, 16, 0, 16]), ('boundary control', ['10:10:10:10', False], [16, 16, 16, 16]), ('boundary control', ['00:00:00:00', False], [0, 0, 0, 0]), ('normal control', ['00:59:59:00', False], [0, 89, 89, 0]), ('normal control', ['19:10:10:19', False], [25, 16, 16, 25]), ('normal control', ['01:00:00:01', False], [1, 0, 0, 1])], [('regression: transmission order', ['00:00:00;00', False], [64, 0, 0, 0]), ('regression variant: transmission order', ['10:00:10;19', True], [217, 16, 0, 16]), ('partial repair probe: transmission order', ['10:59:10;24', True], [228, 16, 89, 16]), ('partial repair variant: transmission order', ['01:07:00;19', False], [89, 0, 7, 1]), ('boundary control', ['00:00:00:00', False], [0, 0, 0, 0]), ('boundary control', ['10:10:10:10', False], [16, 16, 16, 16]), ('normal control', ['01:00:00:01', False], [1, 0, 0, 1]), ('normal control', ['00:59:59:00', False], [0, 89, 89, 0]), ('normal control', ['19:10:10:19', False], [25, 16, 16, 25])]]\nfor label, args, expected in fixtures[N-1]:\n    check(label, solve(*args), expected)\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":"68041acc378c26a66ffbb70df034738011ffab6a91c24fdc476910b649b895b3","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport re\nN = 1\nobservations = []\ndef solve(tc, color):\n    h,m,s,f=map(int,re.split('[:;]',tc))\n    drop=';' in tc\n    def bcd(v,flags):\n        return (v//10)<<4|v%10|flags\n    b0=bcd(f,(0x40 if drop else 0)|(0x80 if color else 0))\n    b1=bcd(s,0)\n    b2=bcd(m,0)\n    b3=bcd(h,0)\n    return [b3,b2,b1,b0]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[('regression: transmission order', ['23:59:59;29', True], [233, 89, 89, 35]), ('regression variant: transmission order', ['00:00:00:00', True], [128, 0, 0, 0]), ('partial repair probe: transmission order', ['10:10:09;24', False], [100, 9, 16, 16]), ('partial repair variant: transmission order', ['01:00:59;19', True], [217, 89, 0, 1]), ('boundary control', ['00:00:00:00', False], [0, 0, 0, 0]), ('boundary control', ['10:10:10:10', False], [16, 16, 16, 16]), ('normal control', ['00:59:59:00', False], [0, 89, 89, 0]), ('normal control', ['01:00:00:01', False], [1, 0, 0, 1]), ('normal control', ['19:10:10:19', False], [25, 16, 16, 25])], [('regression: transmission order', ['01:02:03;04', False], [68, 3, 2, 1]), ('regression variant: transmission order', ['19:00:09;19', True], [217, 9, 0, 25]), ('partial repair probe: transmission order', ['01:59:10:24', True], [164, 16, 89, 1]), ('partial repair variant: transmission order', ['10:07:59:01', False], [1, 89, 7, 16]), ('boundary control', ['10:10:10:10', False], [16, 16, 16, 16]), ('boundary control', ['00:00:00:00', False], [0, 0, 0, 0]), ('normal control', ['00:59:59:00', False], [0, 89, 89, 0]), ('normal control', ['01:00:00:01', False], [1, 0, 0, 1]), ('normal control', ['19:10:10:19', False], [25, 16, 16, 25])], [('regression: transmission order', ['01:07:10:29', True], [169, 16, 7, 1]), ('regression variant: transmission order', ['01:59:10:24', True], [164, 16, 89, 1]), ('partial repair probe: transmission order', ['00:07:09:29', True], [169, 9, 7, 0]), ('partial repair variant: transmission order', ['23:59:10:09', False], [9, 16, 89, 35]), ('boundary control', ['00:00:00:00', False], [0, 0, 0, 0]), ('boundary control', ['10:10:10:10', False], [16, 16, 16, 16]), ('normal control', ['19:10:10:19', False], [25, 16, 16, 25]), ('normal control', ['00:59:59:00', False], [0, 89, 89, 0]), ('normal control', ['01:00:00:01', False], [1, 0, 0, 1])], [('regression: transmission order', ['10:10:09;24', False], [100, 9, 16, 16]), ('regression variant: transmission order', ['00:07:09:29', True], [169, 9, 7, 0]), ('partial repair probe: transmission order', ['10:00:10;19', True], [217, 16, 0, 16]), ('partial repair variant: transmission order', ['10:00:10;09', False], [73, 16, 0, 16]), ('boundary control', ['10:10:10:10', False], [16, 16, 16, 16]), ('boundary control', ['00:00:00:00', False], [0, 0, 0, 0]), ('normal control', ['00:59:59:00', False], [0, 89, 89, 0]), ('normal control', ['19:10:10:19', False], [25, 16, 16, 25]), ('normal control', ['01:00:00:01', False], [1, 0, 0, 1])], [('regression: transmission order', ['00:00:00;00', False], [64, 0, 0, 0]), ('regression variant: transmission order', ['10:00:10;19', True], [217, 16, 0, 16]), ('partial repair probe: transmission order', ['10:59:10;24', True], [228, 16, 89, 16]), ('partial repair variant: transmission order', ['01:07:00;19', False], [89, 0, 7, 1]), ('boundary control', ['00:00:00:00', False], [0, 0, 0, 0]), ('boundary control', ['10:10:10:10', False], [16, 16, 16, 16]), ('normal control', ['01:00:00:01', False], [1, 0, 0, 1]), ('normal control', ['00:59:59:00', False], [0, 89, 89, 0]), ('normal control', ['19:10:10:19', False], [25, 16, 16, 25])]]\nfor label, args, expected in fixtures[N-1]:\n    check(label, solve(*args), expected)\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":"A deterministic bounded teaching model with a stipulated toy contract; it does not claim conformance to SMPTE or any broadcast standard. 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":"w2-broadcast-timecode-arithmetic-ltc-bcd-packing-transmission-order","generated_at":"2026-09-29T14:49:37.295565+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Timecode arithmetic errors misplace edits, commercial breaks and captions against the broadcast clock.","root_cause":"The bytes are emitted hours first.","sha256":"37b9f076045ed2b01f5130b7b2946056f2e27c2305ba708814fd073ce3559a9f","title":"Linear timecode BCD field packing: transmission order · 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":39.613,"exit_code":1,"observations":[{"actual":[233,89,89,35],"check":"regression: transmission order","expected":[233,89,89,35],"passed":true},{"actual":[128,0,0,0],"check":"regression variant: transmission order","expected":[128,0,0,0],"passed":true},{"actual":[100,16,9,16],"check":"partial repair probe: transmission order","expected":[100,9,16,16],"passed":false},{"actual":[217,0,89,1],"check":"partial repair variant: transmission order","expected":[217,89,0,1],"passed":false},{"actual":[0,0,0,0],"check":"boundary control","expected":[0,0,0,0],"passed":true},{"actual":[16,16,16,16],"check":"boundary control","expected":[16,16,16,16],"passed":true},{"actual":[0,89,89,0],"check":"normal control","expected":[0,89,89,0],"passed":true},{"actual":[1,0,0,1],"check":"normal control","expected":[1,0,0,1],"passed":true},{"actual":[25,16,16,25],"check":"normal control","expected":[25,16,16,25],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression: transmission order\", \"actual\": [233, 89, 89, 35], \"expected\": [233, 89, 89, 35], \"passed\": true}, {\"check\": \"regression variant: transmission order\", \"actual\": [128, 0, 0, 0], \"expected\": [128, 0, 0, 0], \"passed\": true}, {\"check\": \"partial repair probe: transmission order\", \"actual\": [100, 16, 9, 16], \"expected\": [100, 9, 16, 16], \"passed\": false}, {\"check\": \"partial repair variant: transmission order\", \"actual\": [217, 0, 89, 1], \"expected\": [217, 89, 0, 1], \"passed\": false}, {\"check\": \"boundary control\", \"actual\": [0, 0, 0, 0], \"expected\": [0, 0, 0, 0], \"passed\": true}, {\"check\": \"boundary control\", \"actual\": [16, 16, 16, 16], \"expected\": [16, 16, 16, 16], \"passed\": true}, {\"check\": \"normal control\", \"actual\": [0, 89, 89, 0], \"expected\": [0, 89, 89, 0], \"passed\": true}, {\"check\": \"normal control\", \"actual\": [1, 0, 0, 1], \"expected\": [1, 0, 0, 1], \"passed\": true}, {\"check\": \"normal control\", \"actual\": [25, 16, 16, 25], \"expected\": [25, 16, 16, 25], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":38.839,"exit_code":1,"observations":[{"actual":[35,89,89,233],"check":"regression: transmission order","expected":[233,89,89,35],"passed":false},{"actual":[0,0,0,128],"check":"regression variant: transmission order","expected":[128,0,0,0],"passed":false},{"actual":[16,16,9,100],"check":"partial repair probe: transmission order","expected":[100,9,16,16],"passed":false},{"actual":[1,0,89,217],"check":"partial repair variant: transmission order","expected":[217,89,0,1],"passed":false},{"actual":[0,0,0,0],"check":"boundary control","expected":[0,0,0,0],"passed":true},{"actual":[16,16,16,16],"check":"boundary control","expected":[16,16,16,16],"passed":true},{"actual":[0,89,89,0],"check":"normal control","expected":[0,89,89,0],"passed":true},{"actual":[1,0,0,1],"check":"normal control","expected":[1,0,0,1],"passed":true},{"actual":[25,16,16,25],"check":"normal control","expected":[25,16,16,25],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression: transmission order\", \"actual\": [35, 89, 89, 233], \"expected\": [233, 89, 89, 35], \"passed\": false}, {\"check\": \"regression variant: transmission order\", \"actual\": [0, 0, 0, 128], \"expected\": [128, 0, 0, 0], \"passed\": false}, {\"check\": \"partial repair probe: transmission order\", \"actual\": [16, 16, 9, 100], \"expected\": [100, 9, 16, 16], \"passed\": false}, {\"check\": \"partial repair variant: transmission order\", \"actual\": [1, 0, 89, 217], \"expected\": [217, 89, 0, 1], \"passed\": false}, {\"check\": \"boundary control\", \"actual\": [0, 0, 0, 0], \"expected\": [0, 0, 0, 0], \"passed\": true}, {\"check\": \"boundary control\", \"actual\": [16, 16, 16, 16], \"expected\": [16, 16, 16, 16], \"passed\": true}, {\"check\": \"normal control\", \"actual\": [0, 89, 89, 0], \"expected\": [0, 89, 89, 0], \"passed\": true}, {\"check\": \"normal control\", \"actual\": [1, 0, 0, 1], \"expected\": [1, 0, 0, 1], \"passed\": true}, {\"check\": \"normal control\", \"actual\": [25, 16, 16, 25], \"expected\": [25, 16, 16, 25], \"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."}}