{"abstract":"Source-in ignores the destination coverage mask.","category":"Raster compositing","checks":4,"contract":"Source is premultiplied RGBA. Source-in multiplies every channel by normalized destination alpha.","evaluation_group":"xg-source-in-clips-premultiplied","failed_approach":"Masking only source alpha leaves RGB outside the destination coverage.","family":"xg-source-in-clips-premultiplied","id":"FA-10566","implementations":{"attempt":{"sha256":"0369241ef360bf8ba359930275ac911ef42ccdf49b35387c0c13ef131c976bea","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(source, destination_alpha):\n    return source[:3]+[source[3]*destination_alpha]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve(*([0.5, 0.25, 0, 0.5], 0.5)), [0.25, 0.125, 0, 0.25])\ncheck('fixture 2', solve(*([1, 1, 1, 1], 0)), [0, 0, 0, 0])\ncheck('fixture 3', solve(*([0.5, 0, 0, 0.5], 1)), [0.5, 0, 0, 0.5])\ncheck('fixture 4', solve(*([0, 0, 0, 0], 0.5)), [0, 0, 0, 0])\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":"e1a96eac62886f00d8b981b1dba082f04e6a1c59377e074b0098031ddb737a3d","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(source, destination_alpha):\n    return list(source)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve(*([0.5, 0.25, 0, 0.5], 0.5)), [0.25, 0.125, 0, 0.25])\ncheck('fixture 2', solve(*([1, 1, 1, 1], 0)), [0, 0, 0, 0])\ncheck('fixture 3', solve(*([0.5, 0, 0, 0.5], 1)), [0.5, 0, 0, 0.5])\ncheck('fixture 4', solve(*([0, 0, 0, 0], 0.5)), [0, 0, 0, 0])\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"},"fixed":{"sha256":"e244345522ddbf7043651f8fa73800c8bb2084b0c48f9c10e1161698359e11da","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(source, destination_alpha):\n    return [x*destination_alpha for x in source]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve(*([0.5, 0.25, 0, 0.5], 0.5)), [0.25, 0.125, 0, 0.25])\ncheck('fixture 2', solve(*([1, 1, 1, 1], 0)), [0, 0, 0, 0])\ncheck('fixture 3', solve(*([0.5, 0, 0, 0.5], 1)), [0.5, 0, 0, 0.5])\ncheck('fixture 4', solve(*([0, 0, 0, 0], 0.5)), [0, 0, 0, 0])\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":" 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":"xg-source-in-clips-premultiplied","generated_at":"2026-09-29T14:38:40.161891+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A deterministic software graphics stage with explicit channel and coordinate conventions; no hardware, device profile or API behavior is inferred.","repair":"Use the stage contract: Source is premultiplied RGBA. Source-in multiplies every channel by normalized destination alpha.","root_cause":"Source-in ignores the destination coverage mask.","sha256":"54042867d4afbc7ab002b54aacee74b152f84f279619bebe273952bc3857d4af","title":"Source in clips premultiplied · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":42.419,"exit_code":1,"observations":[{"actual":[0.5,0.25,0,0.25],"check":"fixture 1","expected":[0.25,0.125,0,0.25],"passed":false},{"actual":[1,1,1,0],"check":"fixture 2","expected":[0,0,0,0],"passed":false},{"actual":[0.5,0,0,0.5],"check":"fixture 3","expected":[0.5,0,0,0.5],"passed":true},{"actual":[0,0,0,0.0],"check":"fixture 4","expected":[0,0,0,0],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [0.5, 0.25, 0, 0.25], \"expected\": [0.25, 0.125, 0, 0.25], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [1, 1, 1, 0], \"expected\": [0, 0, 0, 0], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [0.5, 0, 0, 0.5], \"expected\": [0.5, 0, 0, 0.5], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [0, 0, 0, 0.0], \"expected\": [0, 0, 0, 0], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":40.044,"exit_code":1,"observations":[{"actual":[0.5,0.25,0,0.5],"check":"fixture 1","expected":[0.25,0.125,0,0.25],"passed":false},{"actual":[1,1,1,1],"check":"fixture 2","expected":[0,0,0,0],"passed":false},{"actual":[0.5,0,0,0.5],"check":"fixture 3","expected":[0.5,0,0,0.5],"passed":true},{"actual":[0,0,0,0],"check":"fixture 4","expected":[0,0,0,0],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [0.5, 0.25, 0, 0.5], \"expected\": [0.25, 0.125, 0, 0.25], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [1, 1, 1, 1], \"expected\": [0, 0, 0, 0], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [0.5, 0, 0, 0.5], \"expected\": [0.5, 0, 0, 0.5], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [0, 0, 0, 0], \"expected\": [0, 0, 0, 0], \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":38.648,"exit_code":0,"observations":[{"actual":[0.25,0.125,0.0,0.25],"check":"fixture 1","expected":[0.25,0.125,0,0.25],"passed":true},{"actual":[0,0,0,0],"check":"fixture 2","expected":[0,0,0,0],"passed":true},{"actual":[0.5,0,0,0.5],"check":"fixture 3","expected":[0.5,0,0,0.5],"passed":true},{"actual":[0.0,0.0,0.0,0.0],"check":"fixture 4","expected":[0,0,0,0],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [0.25, 0.125, 0.0, 0.25], \"expected\": [0.25, 0.125, 0, 0.25], \"passed\": true}, {\"check\": \"fixture 2\", \"actual\": [0, 0, 0, 0], \"expected\": [0, 0, 0, 0], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [0.5, 0, 0, 0.5], \"expected\": [0.5, 0, 0, 0.5], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [0.0, 0.0, 0.0, 0.0], \"expected\": [0, 0, 0, 0], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}