From bc010ac82591cfc3e26b4cfd113dcc15a13e5e83 Mon Sep 17 00:00:00 2001
From: Florian Pfaff <6773539+FlorianPfaff@users.noreply.github.com>
Date: Sat, 27 Jun 2026 17:48:57 +0200
Subject: [PATCH 1/2] Validate camera projection matrix shapes

---
 src/pyrecest/models/sensor_models.py | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/pyrecest/models/sensor_models.py b/src/pyrecest/models/sensor_models.py
index 1a6a77072..9162f7469 100644
--- a/src/pyrecest/models/sensor_models.py
+++ b/src/pyrecest/models/sensor_models.py
@@ -126,6 +126,13 @@ def _as_vector(value, length: int, name: str):
     return vector
 
 
+def _as_matrix(value, shape: tuple[int, int], name: str):
+    matrix = asarray(value)
+    if tuple(matrix.shape) != shape:
+        raise ValueError(f"{name} must have shape {shape}")
+    return matrix
+
+
 def _as_sensor_positions(value, position_dim: int = 2):
     sensors = asarray(value)
     sensor_shape = tuple(sensors.shape)
@@ -334,7 +341,7 @@ def camera_projection_measurement(
     are returned.
     """
     position = _select(state, position_indices, 3, "position_indices")
-    rotation = asarray(rotation) if rotation is not None else None
+    rotation = None if rotation is None else _as_matrix(rotation, (3, 3), "rotation")
     translation = _as_vector(translation, 3, "translation")
     camera_position = position if rotation is None else matvec(rotation, position)
     camera_position = camera_position + translation
@@ -348,7 +355,7 @@ def camera_projection_measurement(
     )
     if camera_matrix is None:
         return stack([normalized[0], normalized[1]])
-    homogeneous = matvec(asarray(camera_matrix), normalized)
+    homogeneous = matvec(_as_matrix(camera_matrix, (3, 3), "camera_matrix"), normalized)
     _validate_nonzero_scalar(homogeneous[2], "homogeneous camera scale")
     return stack([homogeneous[0] / homogeneous[2], homogeneous[1] / homogeneous[2]])
 

From 48dbe7763048e838c085bbdad31f089547fe4706 Mon Sep 17 00:00:00 2001
From: Florian Pfaff <6773539+FlorianPfaff@users.noreply.github.com>
Date: Sat, 27 Jun 2026 17:49:11 +0200
Subject: [PATCH 2/2] Add camera projection shape validation tests

---
 tests/test_camera_projection_validation.py | 48 ++++++++++++++++++++++
 1 file changed, 48 insertions(+)
 create mode 100644 tests/test_camera_projection_validation.py

diff --git a/tests/test_camera_projection_validation.py b/tests/test_camera_projection_validation.py
new file mode 100644
index 000000000..f7b015e39
--- /dev/null
+++ b/tests/test_camera_projection_validation.py
@@ -0,0 +1,48 @@
+"""Regression tests for camera projection geometry validation."""
+
+import unittest
+
+from pyrecest.backend import array, eye
+from pyrecest.models import camera_projection_measurement
+
+
+class TestCameraProjectionValidation(unittest.TestCase):
+    def test_camera_projection_rejects_malformed_rotation_shape(self):
+        state = array([1.0, 2.0, 4.0])
+
+        invalid_rotations = (
+            array([1.0, 0.0, 0.0]),
+            array([[1.0, 0.0, 0.0], [0.0, 1.0, 0.0]]),
+        )
+        for rotation in invalid_rotations:
+            with self.subTest(rotation_shape=tuple(rotation.shape)):
+                with self.assertRaisesRegex(ValueError, "rotation"):
+                    camera_projection_measurement(state, rotation=rotation)
+
+    def test_camera_projection_rejects_malformed_camera_matrix_shape(self):
+        state = array([1.0, 2.0, 4.0])
+
+        invalid_camera_matrices = (
+            array([1.0, 0.0, 0.0]),
+            array([[1.0, 0.0, 0.0], [0.0, 1.0, 0.0]]),
+        )
+        for camera_matrix in invalid_camera_matrices:
+            with self.subTest(camera_matrix_shape=tuple(camera_matrix.shape)):
+                with self.assertRaisesRegex(ValueError, "camera_matrix"):
+                    camera_projection_measurement(state, camera_matrix=camera_matrix)
+
+    def test_camera_projection_accepts_well_formed_rotation_and_camera_matrix(self):
+        state = array([2.0, 4.0, 2.0])
+        camera_matrix = array([[2.0, 0.0, 10.0], [0.0, 3.0, 20.0], [0.0, 0.0, 1.0]])
+
+        projected = camera_projection_measurement(
+            state,
+            rotation=eye(3),
+            camera_matrix=camera_matrix,
+        )
+
+        self.assertEqual(tuple(projected.shape), (2,))
+
+
+if __name__ == "__main__":
+    unittest.main()