Single directional chamfer distance and non-absolute cosine similarity

Summary: Single directional chamfer distance and option to use non-absolute cosine similarity

Reviewed By: bottler

Differential Revision: D46593980

fbshipit-source-id: b2e591706a0cdde1c2d361614cecebb84a581433
This commit is contained in:
Norman Mueller
2023-06-13 09:09:15 -07:00
committed by Facebook GitHub Bot
parent 573a42cd5f
commit 5ffeb4d580
2 changed files with 326 additions and 121 deletions

View File

@@ -68,6 +68,94 @@ def _handle_pointcloud_input(
return X, lengths, normals
def _chamfer_distance_single_direction(
x,
y,
x_lengths,
y_lengths,
x_normals,
y_normals,
weights,
batch_reduction: Union[str, None],
point_reduction: str,
norm: int,
abs_cosine: bool,
):
return_normals = x_normals is not None and y_normals is not None
N, P1, D = x.shape
# Check if inputs are heterogeneous and create a lengths mask.
is_x_heterogeneous = (x_lengths != P1).any()
x_mask = (
torch.arange(P1, device=x.device)[None] >= x_lengths[:, None]
) # shape [N, P1]
if y.shape[0] != N or y.shape[2] != D:
raise ValueError("y does not have the correct shape.")
if weights is not None:
if weights.size(0) != N:
raise ValueError("weights must be of shape (N,).")
if not (weights >= 0).all():
raise ValueError("weights cannot be negative.")
if weights.sum() == 0.0:
weights = weights.view(N, 1)
if batch_reduction in ["mean", "sum"]:
return (
(x.sum((1, 2)) * weights).sum() * 0.0,
(x.sum((1, 2)) * weights).sum() * 0.0,
)
return ((x.sum((1, 2)) * weights) * 0.0, (x.sum((1, 2)) * weights) * 0.0)
cham_norm_x = x.new_zeros(())
x_nn = knn_points(x, y, lengths1=x_lengths, lengths2=y_lengths, norm=norm, K=1)
cham_x = x_nn.dists[..., 0] # (N, P1)
if is_x_heterogeneous:
cham_x[x_mask] = 0.0
if weights is not None:
cham_x *= weights.view(N, 1)
if return_normals:
# Gather the normals using the indices and keep only value for k=0
x_normals_near = knn_gather(y_normals, x_nn.idx, y_lengths)[..., 0, :]
cosine_sim = F.cosine_similarity(x_normals, x_normals_near, dim=2, eps=1e-6)
# If abs_cosine, ignore orientation and take the absolute value of the cosine sim.
cham_norm_x = 1 - (torch.abs(cosine_sim) if abs_cosine else cosine_sim)
if is_x_heterogeneous:
cham_norm_x[x_mask] = 0.0
if weights is not None:
cham_norm_x *= weights.view(N, 1)
cham_norm_x = cham_norm_x.sum(1) # (N,)
# Apply point reduction
cham_x = cham_x.sum(1) # (N,)
if point_reduction == "mean":
x_lengths_clamped = x_lengths.clamp(min=1)
cham_x /= x_lengths_clamped
if return_normals:
cham_norm_x /= x_lengths_clamped
if batch_reduction is not None:
# batch_reduction == "sum"
cham_x = cham_x.sum()
if return_normals:
cham_norm_x = cham_norm_x.sum()
if batch_reduction == "mean":
div = weights.sum() if weights is not None else max(N, 1)
cham_x /= div
if return_normals:
cham_norm_x /= div
cham_dist = cham_x
cham_normals = cham_norm_x if return_normals else None
return cham_dist, cham_normals
def chamfer_distance(
x,
y,
@@ -79,6 +167,8 @@ def chamfer_distance(
batch_reduction: Union[str, None] = "mean",
point_reduction: str = "mean",
norm: int = 2,
single_directional: bool = False,
abs_cosine: bool = True,
):
"""
Chamfer distance between two pointclouds x and y.
@@ -103,6 +193,14 @@ def chamfer_distance(
point_reduction: Reduction operation to apply for the loss across the
points, can be one of ["mean", "sum"].
norm: int indicates the norm used for the distance. Supports 1 for L1 and 2 for L2.
single_directional: If False (default), loss comes from both the distance between
each point in x and its nearest neighbor in y and each point in y and its nearest
neighbor in x. If True, loss is the distance between each point in x and its
nearest neighbor in y.
abs_cosine: If False, loss_normals is from one minus the cosine similarity.
If True (default), loss_normals is from one minus the absolute value of the
cosine similarity, which means that exactly opposite normals are considered
equivalent to exactly matching normals, i.e. sign does not matter.
Returns:
2-element tuple containing
@@ -112,116 +210,45 @@ def chamfer_distance(
- **loss_normals**: Tensor giving the reduced cosine distance of normals
between pointclouds in x and pointclouds in y. Returns None if
x_normals and y_normals are None.
"""
_validate_chamfer_reduction_inputs(batch_reduction, point_reduction)
if not ((norm == 1) or (norm == 2)):
raise ValueError("Support for 1 or 2 norm.")
x, x_lengths, x_normals = _handle_pointcloud_input(x, x_lengths, x_normals)
y, y_lengths, y_normals = _handle_pointcloud_input(y, y_lengths, y_normals)
return_normals = x_normals is not None and y_normals is not None
N, P1, D = x.shape
P2 = y.shape[1]
# Check if inputs are heterogeneous and create a lengths mask.
is_x_heterogeneous = (x_lengths != P1).any()
is_y_heterogeneous = (y_lengths != P2).any()
x_mask = (
torch.arange(P1, device=x.device)[None] >= x_lengths[:, None]
) # shape [N, P1]
y_mask = (
torch.arange(P2, device=y.device)[None] >= y_lengths[:, None]
) # shape [N, P2]
if y.shape[0] != N or y.shape[2] != D:
raise ValueError("y does not have the correct shape.")
if weights is not None:
if weights.size(0) != N:
raise ValueError("weights must be of shape (N,).")
if not (weights >= 0).all():
raise ValueError("weights cannot be negative.")
if weights.sum() == 0.0:
weights = weights.view(N, 1)
if batch_reduction in ["mean", "sum"]:
return (
(x.sum((1, 2)) * weights).sum() * 0.0,
(x.sum((1, 2)) * weights).sum() * 0.0,
)
return ((x.sum((1, 2)) * weights) * 0.0, (x.sum((1, 2)) * weights) * 0.0)
cham_norm_x = x.new_zeros(())
cham_norm_y = x.new_zeros(())
x_nn = knn_points(x, y, lengths1=x_lengths, lengths2=y_lengths, norm=norm, K=1)
y_nn = knn_points(y, x, lengths1=y_lengths, lengths2=x_lengths, norm=norm, K=1)
cham_x = x_nn.dists[..., 0] # (N, P1)
cham_y = y_nn.dists[..., 0] # (N, P2)
if is_x_heterogeneous:
cham_x[x_mask] = 0.0
if is_y_heterogeneous:
cham_y[y_mask] = 0.0
if weights is not None:
cham_x *= weights.view(N, 1)
cham_y *= weights.view(N, 1)
if return_normals:
# Gather the normals using the indices and keep only value for k=0
x_normals_near = knn_gather(y_normals, x_nn.idx, y_lengths)[..., 0, :]
y_normals_near = knn_gather(x_normals, y_nn.idx, x_lengths)[..., 0, :]
cham_norm_x = 1 - torch.abs(
F.cosine_similarity(x_normals, x_normals_near, dim=2, eps=1e-6)
cham_x, cham_norm_x = _chamfer_distance_single_direction(
x,
y,
x_lengths,
y_lengths,
x_normals,
y_normals,
weights,
batch_reduction,
point_reduction,
norm,
abs_cosine,
)
if single_directional:
return cham_x, cham_norm_x
else:
cham_y, cham_norm_y = _chamfer_distance_single_direction(
y,
x,
y_lengths,
x_lengths,
y_normals,
x_normals,
weights,
batch_reduction,
point_reduction,
norm,
abs_cosine,
)
cham_norm_y = 1 - torch.abs(
F.cosine_similarity(y_normals, y_normals_near, dim=2, eps=1e-6)
return (
cham_x + cham_y,
(cham_norm_x + cham_norm_y) if cham_norm_x is not None else None,
)
if is_x_heterogeneous:
cham_norm_x[x_mask] = 0.0
if is_y_heterogeneous:
cham_norm_y[y_mask] = 0.0
if weights is not None:
cham_norm_x *= weights.view(N, 1)
cham_norm_y *= weights.view(N, 1)
# Apply point reduction
cham_x = cham_x.sum(1) # (N,)
cham_y = cham_y.sum(1) # (N,)
if return_normals:
cham_norm_x = cham_norm_x.sum(1) # (N,)
cham_norm_y = cham_norm_y.sum(1) # (N,)
if point_reduction == "mean":
x_lengths_clamped = x_lengths.clamp(min=1)
y_lengths_clamped = y_lengths.clamp(min=1)
cham_x /= x_lengths_clamped
cham_y /= y_lengths_clamped
if return_normals:
cham_norm_x /= x_lengths_clamped
cham_norm_y /= y_lengths_clamped
if batch_reduction is not None:
# batch_reduction == "sum"
cham_x = cham_x.sum()
cham_y = cham_y.sum()
if return_normals:
cham_norm_x = cham_norm_x.sum()
cham_norm_y = cham_norm_y.sum()
if batch_reduction == "mean":
div = weights.sum() if weights is not None else max(N, 1)
cham_x /= div
cham_y /= div
if return_normals:
cham_norm_x /= div
cham_norm_y /= div
cham_dist = cham_x + cham_y
cham_normals = cham_norm_x + cham_norm_y if return_normals else None
return cham_dist, cham_normals