[Feature] Full angle range (#1061)

* full range added

* precommit hook

* test update

* chirality preserving flip

Author: calcoloergosum

mmrotate/core/bbox/coder/angle_coder.py

@@ -27,10 +27,16 @@ class CSLCoder(BaseBBoxCoder):
     def __init__(self, angle_version, omega=1, window='gaussian', radius=6):
         super().__init__()
         self.angle_version = angle_version
-        assert angle_version in ['oc', 'le90', 'le135']
+        assert angle_version in ['oc', 'le90', 'le135', 'full360']
         assert window in ['gaussian', 'triangle', 'rect', 'pulse']
-        self.angle_range = 90 if angle_version == 'oc' else 180
-        self.angle_offset_dict = {'oc': 0, 'le90': 90, 'le135': 45}
+        self.angle_range = 90 if angle_version == 'oc' else \
+            (360 if angle_version == 'full360' else 180)
+        self.angle_offset_dict = {
+            'oc': 0,
+            'le90': 90,
+            'le135': 45,
+            'full360': 180
+        }
         self.angle_offset = self.angle_offset_dict[angle_version]
         self.omega = omega
         self.window = window

mmrotate/core/bbox/coder/delta_xywha_hbbox_coder.py

@@ -68,7 +68,7 @@ def encode(self, bboxes, gt_bboxes):
         assert bboxes.size(0) == gt_bboxes.size(0)
         assert bboxes.size(-1) == 4
         assert gt_bboxes.size(-1) == 5
-        if self.angle_range in ['oc', 'le135', 'le90']:
+        if self.angle_range in ['oc', 'le135', 'le90', 'full360']:
             return bbox2delta(bboxes, gt_bboxes, self.means, self.stds,
                               self.angle_range, self.norm_factor,
                               self.edge_swap)
@@ -104,7 +104,7 @@ def decode(self,
             assert pred_bboxes.size(1) == bboxes.size(1)
         assert bboxes.size(-1) == 4
         assert pred_bboxes.size(-1) == 5
-        if self.angle_range in ['oc', 'le135', 'le90']:
+        if self.angle_range in ['oc', 'le135', 'le90', 'full360']:
             return delta2bbox(bboxes, pred_bboxes, self.means, self.stds,
                               wh_ratio_clip, self.add_ctr_clamp,
                               self.ctr_clamp, self.angle_range,

mmrotate/core/bbox/coder/delta_xywha_rbbox_coder.py

@@ -67,7 +67,7 @@ def encode(self, bboxes, gt_bboxes):
         assert bboxes.size(0) == gt_bboxes.size(0)
         assert bboxes.size(-1) == 5
         assert gt_bboxes.size(-1) == 5
-        if self.angle_range in ['oc', 'le135', 'le90']:
+        if self.angle_range in ['oc', 'le135', 'le90', 'full360']:
             return bbox2delta(bboxes, gt_bboxes, self.means, self.stds,
                               self.angle_range, self.norm_factor,
                               self.edge_swap, self.proj_xy)
@@ -99,7 +99,7 @@ def decode(self,
             torch.Tensor: Decoded boxes.
         """
         assert pred_bboxes.size(0) == bboxes.size(0)
-        if self.angle_range in ['oc', 'le135', 'le90']:
+        if self.angle_range in ['oc', 'le135', 'le90', 'full360']:
             return delta2bbox(bboxes, pred_bboxes, self.means, self.stds,
                               max_shape, wh_ratio_clip, self.add_ctr_clamp,
                               self.ctr_clamp, self.angle_range,

mmrotate/core/bbox/transforms.py

@@ -108,6 +108,8 @@ def poly2obb(polys, version='oc'):
         results = poly2obb_le135(polys)
     elif version == 'le90':
         results = poly2obb_le90(polys)
+    elif version == 'full360':
+        results = poly2obb_full360(polys)
     else:
         raise NotImplementedError
     return results
@@ -129,6 +131,8 @@ def poly2obb_np(polys, version='oc'):
         results = poly2obb_np_le135(polys)
     elif version == 'le90':
         results = poly2obb_np_le90(polys)
+    elif version == 'full360':
+        results = poly2obb_np_full360(polys)
     else:
         raise NotImplementedError
     return results
@@ -150,6 +154,9 @@ def obb2hbb(rbboxes, version='oc'):
         results = obb2hbb_le135(rbboxes)
     elif version == 'le90':
         results = obb2hbb_le90(rbboxes)
+    elif version == 'full360':
+        # NOTE: same as 90
+        results = obb2hbb_le90(rbboxes)
     else:
         raise NotImplementedError
     return results
@@ -171,6 +178,9 @@ def obb2poly(rbboxes, version='oc'):
         results = obb2poly_le135(rbboxes)
     elif version == 'le90':
         results = obb2poly_le90(rbboxes)
+    elif version == 'full360':
+        # NOTE: same as 90
+        results = obb2poly_le90(rbboxes)
     else:
         raise NotImplementedError
     return results
@@ -192,6 +202,8 @@ def obb2poly_np(rbboxes, version='oc'):
         results = obb2poly_np_le135(rbboxes)
     elif version == 'le90':
         results = obb2poly_np_le90(rbboxes)
+    elif version == 'full360':
+        results = obb2poly_np_full360(rbboxes)
     else:
         raise NotImplementedError
     return results
@@ -213,6 +225,9 @@ def obb2xyxy(rbboxes, version='oc'):
         results = obb2xyxy_le135(rbboxes)
     elif version == 'le90':
         results = obb2xyxy_le90(rbboxes)
+    elif version == 'full360':
+        # NOTE: same as 90
+        results = obb2xyxy_le90(rbboxes)
     else:
         raise NotImplementedError
     return results
@@ -235,6 +250,7 @@ def hbb2obb(hbboxes, version='oc'):
     elif version == 'le90':
         results = hbb2obb_le90(hbboxes)
     else:
+        # NOTE: not well defined for full360. Leave it unimplemented
         raise NotImplementedError
     return results
 
@@ -298,6 +314,31 @@ def poly2obb_le135(polys):
     return torch.stack([x_ctr, y_ctr, width, height, angles], 1)
 
 
+def poly2obb_full360(polys):
+    """Convert polygons to oriented bounding boxes.
+
+    Args:
+        polys (torch.Tensor): [x0,y0,x1,y1,x2,y2,x3,y3]
+
+    Returns:
+        obbs (torch.Tensor): [x_ctr,y_ctr,w,h,angle]
+    """
+    polys = torch.reshape(polys, [-1, 8])
+    pt1, pt2, pt3, _ = polys[..., :8].chunk(4, 1)
+    width = torch.sqrt(
+        torch.pow(pt1[..., 0] - pt2[..., 0], 2) +
+        torch.pow(pt1[..., 1] - pt2[..., 1], 2))
+    height = torch.sqrt(
+        torch.pow(pt2[..., 0] - pt3[..., 0], 2) +
+        torch.pow(pt2[..., 1] - pt3[..., 1], 2))
+    angles = torch.atan2((pt1[..., 1] - pt2[..., 1]),
+                         (pt1[..., 0] - pt2[..., 0]))
+    angles = norm_angle(angles, 'full360')
+    x_ctr = (pt1[..., 0] + pt3[..., 0]) / 2.0
+    y_ctr = (pt1[..., 1] + pt3[..., 1]) / 2.0
+    return torch.stack([x_ctr, y_ctr, width, height, angles], 1)
+
+
 def poly2obb_le90(polys):
     """Convert polygons to oriented bounding boxes.
 
@@ -418,6 +459,33 @@ def poly2obb_np_le90(poly):
     return x, y, w, h, a
 
 
+def poly2obb_np_full360(poly):
+    """Convert polygons to oriented bounding boxes. Assumes head points then
+    tail points.
+
+    Args:
+        polys (ndarray): [x0,y0,x1,y1,x2,y2,x3,y3]
+
+    Returns:
+        obbs (ndarray): [x_ctr,y_ctr,w,h,angle]
+    """
+    pt1, pt2, pt3, pt4 = np.array(poly).reshape((4, 2))
+    x, y = (pt1 + pt2 + pt3 + pt4) / 4.0
+    dx, dy = pt2 - pt1
+    a = np.arctan2(dy, dx)
+    w = np.linalg.norm(pt2 - pt1)
+    h = np.linalg.norm(pt3 - pt2)
+    if w < 2 or h < 2:
+        return
+    while not np.pi > a >= -np.pi:
+        if a >= np.pi:
+            a -= np.pi
+        else:
+            a += np.pi
+    assert np.pi > a >= -np.pi
+    return x, y, w, h, a
+
+
 def obb2poly_oc(rboxes):
     """Convert oriented bounding boxes to polygons.
 
@@ -634,6 +702,26 @@ def hbb2obb_le90(hbboxes):
     return obboxes
 
 
+def hbb2obb_full360(hbboxes):
+    """Convert horizontal bounding boxes to oriented bounding boxes.
+
+    Args:
+        hbbs (torch.Tensor): [x_lt,y_lt,x_rb,y_rb]
+
+    Returns:
+        obbs (torch.Tensor): [x_ctr,y_ctr,w,h,angle]
+    """
+    x = (hbboxes[..., 0] + hbboxes[..., 2]) * 0.5
+    y = (hbboxes[..., 1] + hbboxes[..., 3]) * 0.5
+    w = hbboxes[..., 2] - hbboxes[..., 0]
+    h = hbboxes[..., 3] - hbboxes[..., 1]
+    theta = x.new_zeros(*x.shape)
+    obboxes1 = torch.stack([x, y, w, h, theta], dim=-1)
+    obboxes2 = torch.stack([x, y, h, w, theta - np.pi / 2], dim=-1)
+    obboxes = torch.where((w >= h)[..., None], obboxes1, obboxes2)
+    return obboxes
+
+
 def obb2xyxy_oc(rbboxes):
     """Convert oriented bounding boxes to horizontal bounding boxes.
 
@@ -783,6 +871,31 @@ def obb2poly_np_le90(obboxes):
     return polys
 
 
+def obb2poly_np_full360(obboxes):
+    """Convert oriented bounding boxes to polygons.
+
+    Args:
+        obbs (ndarray): [x_ctr,y_ctr,w,h,angle,score]
+
+    Returns:
+        polys (ndarray): [x0,y0,x1,y1,x2,y2,x3,y3,score]
+    """
+    try:
+        center, w, h, theta, score = np.split(obboxes, (2, 3, 4, 5), axis=-1)
+    except:  # noqa: E722
+        results = np.stack([0., 0., 0., 0., 0., 0., 0., 0., 0.], axis=-1)
+        return results.reshape(1, -1)
+    Cos, Sin = np.cos(theta), np.sin(theta)
+    vector1 = np.concatenate([w / 2 * Cos, w / 2 * Sin], axis=-1)
+    vector2 = np.concatenate([-h / 2 * Sin, h / 2 * Cos], axis=-1)
+    point1 = center - vector1 - vector2
+    point2 = center + vector1 - vector2
+    point3 = center + vector1 + vector2
+    point4 = center - vector1 + vector2
+    polys = np.concatenate([point1, point2, point3, point4, score], axis=-1)
+    return polys
+
+
 def cal_line_length(point1, point2):
     """Calculate the length of line.
 
@@ -863,6 +976,8 @@ def norm_angle(angle, angle_range):
         return (angle + np.pi / 4) % np.pi - np.pi / 4
     elif angle_range == 'le90':
         return (angle + np.pi / 2) % np.pi - np.pi / 2
+    elif angle_range == 'full360':
+        return angle % (2 * np.pi) - np.pi
     else:
         print('Not yet implemented.')
 

mmrotate/datasets/pipelines/transforms.py

@@ -80,8 +80,10 @@ def bbox_flip(self, bboxes, img_shape, direction):
         flipped = bboxes.copy()
         if direction == 'horizontal':
             flipped[:, 0] = img_shape[1] - bboxes[:, 0] - 1
+            flipped[:4] = flipped[[1, 0, 3, 2]].copy()
         elif direction == 'vertical':
             flipped[:, 1] = img_shape[0] - bboxes[:, 1] - 1
+            flipped[:4] = flipped[[1, 0, 3, 2]].copy()
         elif direction == 'diagonal':
             flipped[:, 0] = img_shape[1] - bboxes[:, 0] - 1
             flipped[:, 1] = img_shape[0] - bboxes[:, 1] - 1
@@ -271,7 +273,6 @@ def __call__(self, results):
     def __repr__(self):
         repr_str = self.__class__.__name__
         repr_str += f'(rotate_ratio={self.rotate_ratio}, ' \
-                    f'base_angles={self.base_angles}, ' \
                     f'angles_range={self.angles_range}, ' \
                     f'auto_bound={self.auto_bound})'
         return repr_str

tests/test_utils/test_transformer.py

@@ -28,3 +28,23 @@ def test_transforms():
     obboxes3 = rtf.hbb2obb(hbboxes, 'le90')
     assert not np.allclose(obboxes1.numpy(), obboxes2)
     assert np.allclose(obboxes2.numpy(), obboxes3)
+
+    # test full360
+    # Check obb2poly and poly2obb is inverse function in full360 rotation
+    for angle in np.linspace(-.9 * np.pi, .9 * np.pi, 4):
+        # numpy version
+        box_np = np.array((100, 100, 80, 50, angle), dtype=np.float32)
+        pts_np = rtf.obb2poly_np(box_np[None], version='full360')[0]
+        box2_np = rtf.poly2obb_np(pts_np, version='full360')
+        np.testing.assert_almost_equal(box_np, box2_np, decimal=4)
+
+        # torch version
+        box_torch = torch.tensor((100, 100, 80, 50, angle),
+                                 dtype=torch.float32)
+        pts_torch = rtf.obb2poly(box_torch[None], version='full360')[0]
+        box2_torch = rtf.poly2obb(pts_torch, version='full360')[0]
+        torch.norm(box_torch - box2_torch) < 1e-4
+
+        # compatibility between numpy and torch implementations
+        torch.norm(box_torch - torch.from_numpy(box_np)) < 1e-4
+        torch.norm(pts_torch - torch.from_numpy(pts_np)) < 1e-4