component decomposition is done

docs/02_components/helpers/h07_image_rotation_utils_spec.md

@@ -0,0 +1,92 @@
+# Image Rotation Utils Helper
+
+## Interface Definition
+
+**Interface Name**: `IImageRotationUtils`
+
+### Interface Methods
+
+```python
+class IImageRotationUtils(ABC):
+    @abstractmethod
+    def rotate_image(self, image: np.ndarray, angle: float, center: Optional[Tuple[int, int]] = None) -> np.ndarray:
+        pass
+    
+    @abstractmethod
+    def calculate_rotation_from_points(self, src_points: np.ndarray, dst_points: np.ndarray) -> float:
+        pass
+    
+    @abstractmethod
+    def normalize_angle(self, angle: float) -> float:
+        pass
+    
+    @abstractmethod
+    def compute_rotation_matrix(self, angle: float, center: Tuple[int, int]) -> np.ndarray:
+        pass
+```
+
+## Component Description
+
+Image rotation operations, angle calculations from point shifts.
+
+## API Methods
+
+### `rotate_image(image: np.ndarray, angle: float, center: Optional[Tuple[int, int]] = None) -> np.ndarray`
+
+**Description**: Rotates image around center.
+
+**Implementation**: Uses cv2.getRotationMatrix2D + cv2.warpAffine
+
+**Parameters**:
+- **angle**: Degrees (0-360)
+- **center**: Rotation center (default: image center)
+
+**Returns**: Rotated image (same dimensions)
+
+---
+
+### `calculate_rotation_from_points(src_points: np.ndarray, dst_points: np.ndarray) -> float`
+
+**Description**: Calculates rotation angle from point correspondences.
+
+**Input**: (N, 2) arrays of matching points
+
+**Algorithm**:
+1. Compute centroids
+2. Calculate angle from centroid shifts
+3. Return angle in degrees
+
+**Use Case**: Extract precise angle from LiteSAM homography
+
+---
+
+### `normalize_angle(angle: float) -> float`
+
+**Description**: Normalizes angle to 0-360 range.
+
+**Formula**:
+```
+angle = angle % 360
+if angle < 0:
+    angle += 360
+```
+
+---
+
+### `compute_rotation_matrix(angle: float, center: Tuple[int, int]) -> np.ndarray`
+
+**Description**: Computes 2D rotation matrix.
+
+**Returns**: 2×3 affine transformation matrix
+
+## Dependencies
+
+**External**: opencv-python, numpy
+
+## Test Cases
+
+1. Rotate 90° → image rotated correctly
+2. Calculate angle from points → accurate angle
+3. Normalize 370° → 10°
+4. Rotation matrix → correct transformation
+