FAILURE MAP
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FA-79196 / Image orientation metadata / Open access

Vertical mirror translates by the width · case 01

Top-bottom mirrored scans are drawn partly outside the canvas.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The y translation of the vertical mirror uses w instead of h.

VERIFIED REPAIR

Translate by h so y' = h - y.

Unsuccessful approach: Negating x instead of y mirrors the wrong axis.

Case contract

Input [w, h, tag]. Produce the canvas size and the 2D affine [a, b, c, d, e, f] (x' = a*x + c*y + e, y' = b*x + d*y + f, continuous coordinates, so mirroring an extent e maps x to e - x) that draws the stored image upright. Tags 5..8 use a [h, w] canvas; invalid tags are treated as 1.

Why this case matters

Camera, phone and scanner images carry an orientation hint separately from the stored pixels; galleries, thumbnailers, editors and upload pipelines must interpret it consistently or photos appear sideways, mirrored or doubly rotated.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    w, h, tag = x
    if tag not in (1, 2, 3, 4, 5, 6, 7, 8):
        tag = 1
    if tag == 1:
        mat = [1, 0, 0, 1, 0, 0]
    elif tag == 2:
        mat = [-1, 0, 0, 1, w, 0]
    elif tag == 3:
        mat = [-1, 0, 0, -1, w, h]
    elif tag == 4:
        mat = [1, 0, 0, -1, 0, w]
    elif tag == 5:
        mat = [0, 1, 1, 0, 0, 0]
    elif tag == 6:
        mat = [0, 1, -1, 0, h, 0]
    elif tag == 7:
        mat = [0, -1, -1, 0, h, w]
    else:
        mat = [0, -1, 1, 0, 0, w]
    canvas = [h, w] if tag >= 5 else [w, h]
    return {'canvas': canvas, 'matrix': mat}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[1990, 1071, 4], {'canvas': [1990, 1071], 'matrix': [1, 0, 0, -1, 0, 1071]}], [[3937, 494, 4], {'canvas': [3937, 494], 'matrix': [1, 0, 0, -1, 0, 494]}], [[3307, 2787, 3], {'canvas': [3307, 2787], 'matrix': [-1, 0, 0, -1, 3307, 2787]}], [[2954, 1709, 1], {'canvas': [2954, 1709], 'matrix': [1, 0, 0, 1, 0, 0]}], [[58, 1879, 3], {'canvas': [58, 1879], 'matrix': [-1, 0, 0, -1, 58, 1879]}], [[2834, 740, 9], {'canvas': [2834, 740], 'matrix': [1, 0, 0, 1, 0, 0]}], [[1435, 891, 8], {'canvas': [891, 1435], 'matrix': [0, -1, 1, 0, 0, 1435]}], [[405, 330, 4], {'canvas': [405, 330], 'matrix': [1, 0, 0, -1, 0, 330]}]], [[[3777, 2930, 4], {'canvas': [3777, 2930], 'matrix': [1, 0, 0, -1, 0, 2930]}], [[750, 3, 4], {'canvas': [750, 3], 'matrix': [1, 0, 0, -1, 0, 3]}], [[1404, 638, 8], {'canvas': [638, 1404], 'matrix': [0, -1, 1, 0, 0, 1404]}], [[3672, 2107, 7], {'canvas': [2107, 3672], 'matrix': [0, -1, -1, 0, 2107, 3672]}], [[497, 2889, 6], {'canvas': [2889, 497], 'matrix': [0, 1, -1, 0, 2889, 0]}], [[1679, 3857, 0], {'canvas': [1679, 3857], 'matrix': [1, 0, 0, 1, 0, 0]}], [[1194, 3699, 6], {'canvas': [3699, 1194], 'matrix': [0, 1, -1, 0, 3699, 0]}], [[3404, 3893, 4], {'canvas': [3404, 3893], 'matrix': [1, 0, 0, -1, 0, 3893]}]], [[[3103, 1780, 4], {'canvas': [3103, 1780], 'matrix': [1, 0, 0, -1, 0, 1780]}], [[3206, 3368, 4], {'canvas': [3206, 3368], 'matrix': [1, 0, 0, -1, 0, 3368]}], [[2580, 3384, 7], {'canvas': [3384, 2580], 'matrix': [0, -1, -1, 0, 3384, 2580]}], [[1742, 3974, 6], {'canvas': [3974, 1742], 'matrix': [0, 1, -1, 0, 3974, 0]}], [[2878, 1614, 0], {'canvas': [2878, 1614], 'matrix': [1, 0, 0, 1, 0, 0]}], [[1553, 978, 5], {'canvas': [978, 1553], 'matrix': [0, 1, 1, 0, 0, 0]}], [[2394, 1311, 0], {'canvas': [2394, 1311], 'matrix': [1, 0, 0, 1, 0, 0]}], [[1055, 2412, 4], {'canvas': [1055, 2412], 'matrix': [1, 0, 0, -1, 0, 2412]}]], [[[3657, 1928, 4], {'canvas': [3657, 1928], 'matrix': [1, 0, 0, -1, 0, 1928]}], [[3645, 981, 4], {'canvas': [3645, 981], 'matrix': [1, 0, 0, -1, 0, 981]}], [[1728, 2634, 3], {'canvas': [1728, 2634], 'matrix': [-1, 0, 0, -1, 1728, 2634]}], [[2618, 2128, 9], {'canvas': [2618, 2128], 'matrix': [1, 0, 0, 1, 0, 0]}], [[2422, 1413, 3], {'canvas': [2422, 1413], 'matrix': [-1, 0, 0, -1, 2422, 1413]}], [[397, 3269, 8], {'canvas': [3269, 397], 'matrix': [0, -1, 1, 0, 0, 397]}], [[3842, 908, 7], {'canvas': [908, 3842], 'matrix': [0, -1, -1, 0, 908, 3842]}], [[1502, 2001, 4], {'canvas': [1502, 2001], 'matrix': [1, 0, 0, -1, 0, 2001]}]], [[[3008, 525, 4], {'canvas': [3008, 525], 'matrix': [1, 0, 0, -1, 0, 525]}], [[1288, 1989, 4], {'canvas': [1288, 1989], 'matrix': [1, 0, 0, -1, 0, 1989]}], [[3666, 647, 2], {'canvas': [3666, 647], 'matrix': [-1, 0, 0, 1, 3666, 0]}], [[3653, 369, 3], {'canvas': [3653, 369], 'matrix': [-1, 0, 0, -1, 3653, 369]}], [[663, 894, 6], {'canvas': [894, 663], 'matrix': [0, 1, -1, 0, 894, 0]}], [[439, 1611, 8], {'canvas': [1611, 439], 'matrix': [0, -1, 1, 0, 0, 439]}], [[2083, 1309, 2], {'canvas': [2083, 1309], 'matrix': [-1, 0, 0, 1, 2083, 0]}], [[1475, 1734, 4], {'canvas': [1475, 1734], 'matrix': [1, 0, 0, -1, 0, 1734]}]]]
labels = ["regression: vertical mirror offset", "repair trap", "combined fault", "control", "control", "boundary", "boundary", "control"]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("%s %d" % (labels[i % len(labels)], i), solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: vertical mirror offset 0{'canvas': [1990, 1071], 'matrix': [1, 0, 0, -1, 0, 1990]}{'canvas': [1990, 1071], 'matrix': [1, 0, 0, -1, 0, 1071]}Failed
repair trap 1{'canvas': [3937, 494], 'matrix': [1, 0, 0, -1, 0, 3937]}{'canvas': [3937, 494], 'matrix': [1, 0, 0, -1, 0, 494]}Failed
combined fault 2{'canvas': [3307, 2787], 'matrix': [-1, 0, 0, -1, 3307, 2787]}{'canvas': [3307, 2787], 'matrix': [-1, 0, 0, -1, 3307, 2787]}Passed
control 3{'canvas': [2954, 1709], 'matrix': [1, 0, 0, 1, 0, 0]}{'canvas': [2954, 1709], 'matrix': [1, 0, 0, 1, 0, 0]}Passed
control 4{'canvas': [58, 1879], 'matrix': [-1, 0, 0, -1, 58, 1879]}{'canvas': [58, 1879], 'matrix': [-1, 0, 0, -1, 58, 1879]}Passed
boundary 5{'canvas': [2834, 740], 'matrix': [1, 0, 0, 1, 0, 0]}{'canvas': [2834, 740], 'matrix': [1, 0, 0, 1, 0, 0]}Passed
boundary 6{'canvas': [891, 1435], 'matrix': [0, -1, 1, 0, 0, 1435]}{'canvas': [891, 1435], 'matrix': [0, -1, 1, 0, 0, 1435]}Passed
control 7{'canvas': [405, 330], 'matrix': [1, 0, 0, -1, 0, 405]}{'canvas': [405, 330], 'matrix': [1, 0, 0, -1, 0, 330]}Failed

SHA-256 / 29314a36e1f7546ce27d1ffd851ba1badc4cdd8a884d27a27c1dfa64a95cab93

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    w, h, tag = x
    if tag not in (1, 2, 3, 4, 5, 6, 7, 8):
        tag = 1
    if tag == 1:
        mat = [1, 0, 0, 1, 0, 0]
    elif tag == 2:
        mat = [-1, 0, 0, 1, w, 0]
    elif tag == 3:
        mat = [-1, 0, 0, -1, w, h]
    elif tag == 4:
        mat = [-1, 0, 0, 1, 0, h]
    elif tag == 5:
        mat = [0, 1, 1, 0, 0, 0]
    elif tag == 6:
        mat = [0, 1, -1, 0, h, 0]
    elif tag == 7:
        mat = [0, -1, -1, 0, h, w]
    else:
        mat = [0, -1, 1, 0, 0, w]
    canvas = [h, w] if tag >= 5 else [w, h]
    return {'canvas': canvas, 'matrix': mat}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[1990, 1071, 4], {'canvas': [1990, 1071], 'matrix': [1, 0, 0, -1, 0, 1071]}], [[3937, 494, 4], {'canvas': [3937, 494], 'matrix': [1, 0, 0, -1, 0, 494]}], [[3307, 2787, 3], {'canvas': [3307, 2787], 'matrix': [-1, 0, 0, -1, 3307, 2787]}], [[2954, 1709, 1], {'canvas': [2954, 1709], 'matrix': [1, 0, 0, 1, 0, 0]}], [[58, 1879, 3], {'canvas': [58, 1879], 'matrix': [-1, 0, 0, -1, 58, 1879]}], [[2834, 740, 9], {'canvas': [2834, 740], 'matrix': [1, 0, 0, 1, 0, 0]}], [[1435, 891, 8], {'canvas': [891, 1435], 'matrix': [0, -1, 1, 0, 0, 1435]}], [[405, 330, 4], {'canvas': [405, 330], 'matrix': [1, 0, 0, -1, 0, 330]}]], [[[3777, 2930, 4], {'canvas': [3777, 2930], 'matrix': [1, 0, 0, -1, 0, 2930]}], [[750, 3, 4], {'canvas': [750, 3], 'matrix': [1, 0, 0, -1, 0, 3]}], [[1404, 638, 8], {'canvas': [638, 1404], 'matrix': [0, -1, 1, 0, 0, 1404]}], [[3672, 2107, 7], {'canvas': [2107, 3672], 'matrix': [0, -1, -1, 0, 2107, 3672]}], [[497, 2889, 6], {'canvas': [2889, 497], 'matrix': [0, 1, -1, 0, 2889, 0]}], [[1679, 3857, 0], {'canvas': [1679, 3857], 'matrix': [1, 0, 0, 1, 0, 0]}], [[1194, 3699, 6], {'canvas': [3699, 1194], 'matrix': [0, 1, -1, 0, 3699, 0]}], [[3404, 3893, 4], {'canvas': [3404, 3893], 'matrix': [1, 0, 0, -1, 0, 3893]}]], [[[3103, 1780, 4], {'canvas': [3103, 1780], 'matrix': [1, 0, 0, -1, 0, 1780]}], [[3206, 3368, 4], {'canvas': [3206, 3368], 'matrix': [1, 0, 0, -1, 0, 3368]}], [[2580, 3384, 7], {'canvas': [3384, 2580], 'matrix': [0, -1, -1, 0, 3384, 2580]}], [[1742, 3974, 6], {'canvas': [3974, 1742], 'matrix': [0, 1, -1, 0, 3974, 0]}], [[2878, 1614, 0], {'canvas': [2878, 1614], 'matrix': [1, 0, 0, 1, 0, 0]}], [[1553, 978, 5], {'canvas': [978, 1553], 'matrix': [0, 1, 1, 0, 0, 0]}], [[2394, 1311, 0], {'canvas': [2394, 1311], 'matrix': [1, 0, 0, 1, 0, 0]}], [[1055, 2412, 4], {'canvas': [1055, 2412], 'matrix': [1, 0, 0, -1, 0, 2412]}]], [[[3657, 1928, 4], {'canvas': [3657, 1928], 'matrix': [1, 0, 0, -1, 0, 1928]}], [[3645, 981, 4], {'canvas': [3645, 981], 'matrix': [1, 0, 0, -1, 0, 981]}], [[1728, 2634, 3], {'canvas': [1728, 2634], 'matrix': [-1, 0, 0, -1, 1728, 2634]}], [[2618, 2128, 9], {'canvas': [2618, 2128], 'matrix': [1, 0, 0, 1, 0, 0]}], [[2422, 1413, 3], {'canvas': [2422, 1413], 'matrix': [-1, 0, 0, -1, 2422, 1413]}], [[397, 3269, 8], {'canvas': [3269, 397], 'matrix': [0, -1, 1, 0, 0, 397]}], [[3842, 908, 7], {'canvas': [908, 3842], 'matrix': [0, -1, -1, 0, 908, 3842]}], [[1502, 2001, 4], {'canvas': [1502, 2001], 'matrix': [1, 0, 0, -1, 0, 2001]}]], [[[3008, 525, 4], {'canvas': [3008, 525], 'matrix': [1, 0, 0, -1, 0, 525]}], [[1288, 1989, 4], {'canvas': [1288, 1989], 'matrix': [1, 0, 0, -1, 0, 1989]}], [[3666, 647, 2], {'canvas': [3666, 647], 'matrix': [-1, 0, 0, 1, 3666, 0]}], [[3653, 369, 3], {'canvas': [3653, 369], 'matrix': [-1, 0, 0, -1, 3653, 369]}], [[663, 894, 6], {'canvas': [894, 663], 'matrix': [0, 1, -1, 0, 894, 0]}], [[439, 1611, 8], {'canvas': [1611, 439], 'matrix': [0, -1, 1, 0, 0, 439]}], [[2083, 1309, 2], {'canvas': [2083, 1309], 'matrix': [-1, 0, 0, 1, 2083, 0]}], [[1475, 1734, 4], {'canvas': [1475, 1734], 'matrix': [1, 0, 0, -1, 0, 1734]}]]]
labels = ["regression: vertical mirror offset", "repair trap", "combined fault", "control", "control", "boundary", "boundary", "control"]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("%s %d" % (labels[i % len(labels)], i), solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: vertical mirror offset 0{'canvas': [1990, 1071], 'matrix': [-1, 0, 0, 1, 0, 1071]}{'canvas': [1990, 1071], 'matrix': [1, 0, 0, -1, 0, 1071]}Failed
repair trap 1{'canvas': [3937, 494], 'matrix': [-1, 0, 0, 1, 0, 494]}{'canvas': [3937, 494], 'matrix': [1, 0, 0, -1, 0, 494]}Failed
combined fault 2{'canvas': [3307, 2787], 'matrix': [-1, 0, 0, -1, 3307, 2787]}{'canvas': [3307, 2787], 'matrix': [-1, 0, 0, -1, 3307, 2787]}Passed
control 3{'canvas': [2954, 1709], 'matrix': [1, 0, 0, 1, 0, 0]}{'canvas': [2954, 1709], 'matrix': [1, 0, 0, 1, 0, 0]}Passed
control 4{'canvas': [58, 1879], 'matrix': [-1, 0, 0, -1, 58, 1879]}{'canvas': [58, 1879], 'matrix': [-1, 0, 0, -1, 58, 1879]}Passed
boundary 5{'canvas': [2834, 740], 'matrix': [1, 0, 0, 1, 0, 0]}{'canvas': [2834, 740], 'matrix': [1, 0, 0, 1, 0, 0]}Passed
boundary 6{'canvas': [891, 1435], 'matrix': [0, -1, 1, 0, 0, 1435]}{'canvas': [891, 1435], 'matrix': [0, -1, 1, 0, 0, 1435]}Passed
control 7{'canvas': [405, 330], 'matrix': [-1, 0, 0, 1, 0, 330]}{'canvas': [405, 330], 'matrix': [1, 0, 0, -1, 0, 330]}Failed

SHA-256 / 2bcc065b1a4717f395cb387c178b92999154a834a4102208468f22f8f927639d

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    w, h, tag = x
    if tag not in (1, 2, 3, 4, 5, 6, 7, 8):
        tag = 1
    if tag == 1:
        mat = [1, 0, 0, 1, 0, 0]
    elif tag == 2:
        mat = [-1, 0, 0, 1, w, 0]
    elif tag == 3:
        mat = [-1, 0, 0, -1, w, h]
    elif tag == 4:
        mat = [1, 0, 0, -1, 0, h]
    elif tag == 5:
        mat = [0, 1, 1, 0, 0, 0]
    elif tag == 6:
        mat = [0, 1, -1, 0, h, 0]
    elif tag == 7:
        mat = [0, -1, -1, 0, h, w]
    else:
        mat = [0, -1, 1, 0, 0, w]
    canvas = [h, w] if tag >= 5 else [w, h]
    return {'canvas': canvas, 'matrix': mat}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[1990, 1071, 4], {'canvas': [1990, 1071], 'matrix': [1, 0, 0, -1, 0, 1071]}], [[3937, 494, 4], {'canvas': [3937, 494], 'matrix': [1, 0, 0, -1, 0, 494]}], [[3307, 2787, 3], {'canvas': [3307, 2787], 'matrix': [-1, 0, 0, -1, 3307, 2787]}], [[2954, 1709, 1], {'canvas': [2954, 1709], 'matrix': [1, 0, 0, 1, 0, 0]}], [[58, 1879, 3], {'canvas': [58, 1879], 'matrix': [-1, 0, 0, -1, 58, 1879]}], [[2834, 740, 9], {'canvas': [2834, 740], 'matrix': [1, 0, 0, 1, 0, 0]}], [[1435, 891, 8], {'canvas': [891, 1435], 'matrix': [0, -1, 1, 0, 0, 1435]}], [[405, 330, 4], {'canvas': [405, 330], 'matrix': [1, 0, 0, -1, 0, 330]}]], [[[3777, 2930, 4], {'canvas': [3777, 2930], 'matrix': [1, 0, 0, -1, 0, 2930]}], [[750, 3, 4], {'canvas': [750, 3], 'matrix': [1, 0, 0, -1, 0, 3]}], [[1404, 638, 8], {'canvas': [638, 1404], 'matrix': [0, -1, 1, 0, 0, 1404]}], [[3672, 2107, 7], {'canvas': [2107, 3672], 'matrix': [0, -1, -1, 0, 2107, 3672]}], [[497, 2889, 6], {'canvas': [2889, 497], 'matrix': [0, 1, -1, 0, 2889, 0]}], [[1679, 3857, 0], {'canvas': [1679, 3857], 'matrix': [1, 0, 0, 1, 0, 0]}], [[1194, 3699, 6], {'canvas': [3699, 1194], 'matrix': [0, 1, -1, 0, 3699, 0]}], [[3404, 3893, 4], {'canvas': [3404, 3893], 'matrix': [1, 0, 0, -1, 0, 3893]}]], [[[3103, 1780, 4], {'canvas': [3103, 1780], 'matrix': [1, 0, 0, -1, 0, 1780]}], [[3206, 3368, 4], {'canvas': [3206, 3368], 'matrix': [1, 0, 0, -1, 0, 3368]}], [[2580, 3384, 7], {'canvas': [3384, 2580], 'matrix': [0, -1, -1, 0, 3384, 2580]}], [[1742, 3974, 6], {'canvas': [3974, 1742], 'matrix': [0, 1, -1, 0, 3974, 0]}], [[2878, 1614, 0], {'canvas': [2878, 1614], 'matrix': [1, 0, 0, 1, 0, 0]}], [[1553, 978, 5], {'canvas': [978, 1553], 'matrix': [0, 1, 1, 0, 0, 0]}], [[2394, 1311, 0], {'canvas': [2394, 1311], 'matrix': [1, 0, 0, 1, 0, 0]}], [[1055, 2412, 4], {'canvas': [1055, 2412], 'matrix': [1, 0, 0, -1, 0, 2412]}]], [[[3657, 1928, 4], {'canvas': [3657, 1928], 'matrix': [1, 0, 0, -1, 0, 1928]}], [[3645, 981, 4], {'canvas': [3645, 981], 'matrix': [1, 0, 0, -1, 0, 981]}], [[1728, 2634, 3], {'canvas': [1728, 2634], 'matrix': [-1, 0, 0, -1, 1728, 2634]}], [[2618, 2128, 9], {'canvas': [2618, 2128], 'matrix': [1, 0, 0, 1, 0, 0]}], [[2422, 1413, 3], {'canvas': [2422, 1413], 'matrix': [-1, 0, 0, -1, 2422, 1413]}], [[397, 3269, 8], {'canvas': [3269, 397], 'matrix': [0, -1, 1, 0, 0, 397]}], [[3842, 908, 7], {'canvas': [908, 3842], 'matrix': [0, -1, -1, 0, 908, 3842]}], [[1502, 2001, 4], {'canvas': [1502, 2001], 'matrix': [1, 0, 0, -1, 0, 2001]}]], [[[3008, 525, 4], {'canvas': [3008, 525], 'matrix': [1, 0, 0, -1, 0, 525]}], [[1288, 1989, 4], {'canvas': [1288, 1989], 'matrix': [1, 0, 0, -1, 0, 1989]}], [[3666, 647, 2], {'canvas': [3666, 647], 'matrix': [-1, 0, 0, 1, 3666, 0]}], [[3653, 369, 3], {'canvas': [3653, 369], 'matrix': [-1, 0, 0, -1, 3653, 369]}], [[663, 894, 6], {'canvas': [894, 663], 'matrix': [0, 1, -1, 0, 894, 0]}], [[439, 1611, 8], {'canvas': [1611, 439], 'matrix': [0, -1, 1, 0, 0, 439]}], [[2083, 1309, 2], {'canvas': [2083, 1309], 'matrix': [-1, 0, 0, 1, 2083, 0]}], [[1475, 1734, 4], {'canvas': [1475, 1734], 'matrix': [1, 0, 0, -1, 0, 1734]}]]]
labels = ["regression: vertical mirror offset", "repair trap", "combined fault", "control", "control", "boundary", "boundary", "control"]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("%s %d" % (labels[i % len(labels)], i), solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: vertical mirror offset 0{'canvas': [1990, 1071], 'matrix': [1, 0, 0, -1, 0, 1071]}{'canvas': [1990, 1071], 'matrix': [1, 0, 0, -1, 0, 1071]}Passed
repair trap 1{'canvas': [3937, 494], 'matrix': [1, 0, 0, -1, 0, 494]}{'canvas': [3937, 494], 'matrix': [1, 0, 0, -1, 0, 494]}Passed
combined fault 2{'canvas': [3307, 2787], 'matrix': [-1, 0, 0, -1, 3307, 2787]}{'canvas': [3307, 2787], 'matrix': [-1, 0, 0, -1, 3307, 2787]}Passed
control 3{'canvas': [2954, 1709], 'matrix': [1, 0, 0, 1, 0, 0]}{'canvas': [2954, 1709], 'matrix': [1, 0, 0, 1, 0, 0]}Passed
control 4{'canvas': [58, 1879], 'matrix': [-1, 0, 0, -1, 58, 1879]}{'canvas': [58, 1879], 'matrix': [-1, 0, 0, -1, 58, 1879]}Passed
boundary 5{'canvas': [2834, 740], 'matrix': [1, 0, 0, 1, 0, 0]}{'canvas': [2834, 740], 'matrix': [1, 0, 0, 1, 0, 0]}Passed
boundary 6{'canvas': [891, 1435], 'matrix': [0, -1, 1, 0, 0, 1435]}{'canvas': [891, 1435], 'matrix': [0, -1, 1, 0, 0, 1435]}Passed
control 7{'canvas': [405, 330], 'matrix': [1, 0, 0, -1, 0, 330]}{'canvas': [405, 330], 'matrix': [1, 0, 0, -1, 0, 330]}Passed

SHA-256 / 75d4a859644b1f95978599e9f2d1868b55be98f70f12491ef23c5250cd04f43f

Verification & scope

A deterministic bounded teaching model with a stipulated contract; it makes no claim of conformance to any published specification. 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.

Observations recorded using Python 3.12.14 at 2026-09-29T14:49:42.405347+00:00.

Case digest / 9b2fa541fa1623f3af1f06ee606c6da0aad2cd8beb09e0f14c84da472ae85857