feat: update pairwise cosface and pairwise circle loss

This commit is contained in:
liaoxingyu 2020-12-22 15:51:49 +08:00
parent 66941cf27a
commit 766f309d03
4 changed files with 58 additions and 280 deletions

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@ -6,36 +6,27 @@
import torch
import torch.nn.functional as F
from torch import nn
from fastreid.utils import comm
from .utils import concat_all_gather
__all__ = ["pairwise_circleloss", "pairwise_cosface"]
def circle_loss(
def pairwise_circleloss(
embedding: torch.Tensor,
targets: torch.Tensor,
margin: float,
alpha: float,) -> torch.Tensor:
embedding = nn.functional.normalize(embedding, dim=1)
gamma: float, ) -> torch.Tensor:
embedding = F.normalize(embedding, dim=1)
if comm.get_world_size() > 1:
all_embedding = concat_all_gather(embedding)
all_targets = concat_all_gather(targets)
else:
all_embedding = embedding
all_targets = targets
dist_mat = torch.matmul(all_embedding, all_embedding.t())
dist_mat = torch.matmul(embedding, embedding.t())
N = dist_mat.size(0)
is_pos = all_targets.view(N, 1).expand(N, N).eq(all_targets.view(N, 1).expand(N, N).t()).float()
# Compute the mask which ignores the relevance score of the query to itself
is_pos = targets.view(N, 1).expand(N, N).eq(targets.view(N, 1).expand(N, N).t()).float()
is_neg = targets.view(N, 1).expand(N, N).ne(targets.view(N, 1).expand(N, N).t()).float()
# Mask scores related to itself
is_pos = is_pos - torch.eye(N, N, device=is_pos.device)
is_neg = all_targets.view(N, 1).expand(N, N).ne(all_targets.view(N, 1).expand(N, N).t())
s_p = dist_mat * is_pos
s_n = dist_mat * is_neg
@ -44,9 +35,37 @@ def circle_loss(
delta_p = 1 - margin
delta_n = margin
logit_p = - alpha * alpha_p * (s_p - delta_p)
logit_n = alpha * alpha_n * (s_n - delta_n)
logit_p = - gamma * alpha_p * (s_p - delta_p) + (-99999999.) * (1 - is_pos)
logit_n = gamma * alpha_n * (s_n - delta_n) + (-99999999.) * (1 - is_neg)
loss = nn.functional.softplus(torch.logsumexp(logit_p, dim=1) + torch.logsumexp(logit_n, dim=1)).mean()
loss = F.softplus(torch.logsumexp(logit_p, dim=1) + torch.logsumexp(logit_n, dim=1)).mean()
return loss
def pairwise_cosface(
embedding: torch.Tensor,
targets: torch.Tensor,
margin: float,
gamma: float, ) -> torch.Tensor:
# Normalize embedding features
embedding = F.normalize(embedding, dim=1)
dist_mat = torch.matmul(embedding, embedding.t())
N = dist_mat.size(0)
is_pos = targets.view(N, 1).expand(N, N).eq(targets.view(N, 1).expand(N, N).t()).float()
is_neg = targets.view(N, 1).expand(N, N).ne(targets.view(N, 1).expand(N, N).t()).float()
# Mask scores related to itself
is_pos = is_pos - torch.eye(N, N, device=is_pos.device)
s_p = dist_mat * is_pos
s_n = dist_mat * is_neg
logit_p = -gamma * s_p + (-99999999.) * (1 - is_pos)
logit_n = gamma * (s_n + margin) + (-99999999.) * (1 - is_neg)
loss = F.softplus(torch.logsumexp(logit_p, dim=1) + torch.logsumexp(logit_n, dim=1)).mean()
return loss

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@ -1,241 +0,0 @@
# encoding: utf-8
"""
@author: xingyu liao
@contact: sherlockliao01@gmail.com
"""
# based on:
# https://github.com/Andrew-Brown1/Smooth_AP/blob/master/src/Smooth_AP_loss.py
import torch
import torch.nn.functional as F
from fastreid.utils import comm
from fastreid.modeling.losses.utils import concat_all_gather
def sigmoid(tensor, temp=1.0):
""" temperature controlled sigmoid
takes as input a torch tensor (tensor) and passes it through a sigmoid, controlled by temperature: temp
"""
exponent = -tensor / temp
# clamp the input tensor for stability
exponent = torch.clamp(exponent, min=-50, max=50)
y = 1.0 / (1.0 + torch.exp(exponent))
return y
class SmoothAP(object):
r"""PyTorch implementation of the Smooth-AP loss.
implementation of the Smooth-AP loss. Takes as input the mini-batch of CNN-produced feature embeddings and returns
the value of the Smooth-AP loss. The mini-batch must be formed of a defined number of classes. Each class must
have the same number of instances represented in the mini-batch and must be ordered sequentially by class.
e.g. the labels for a mini-batch with batch size 9, and 3 represented classes (A,B,C) must look like:
labels = ( A, A, A, B, B, B, C, C, C)
(the order of the classes however does not matter)
For each instance in the mini-batch, the loss computes the Smooth-AP when it is used as the query and the rest of the
mini-batch is used as the retrieval set. The positive set is formed of the other instances in the batch from the
same class. The loss returns the average Smooth-AP across all instances in the mini-batch.
Args:
anneal : float
the temperature of the sigmoid that is used to smooth the ranking function. A low value of the temperature
results in a steep sigmoid, that tightly approximates the heaviside step function in the ranking function.
batch_size : int
the batch size being used during training.
num_id : int
the number of different classes that are represented in the batch.
feat_dims : int
the dimension of the input feature embeddings
Shape:
- Input (preds): (batch_size, feat_dims) (must be a cuda torch float tensor)
- Output: scalar
Examples::
>>> loss = SmoothAP(0.01, 60, 6, 256)
>>> input = torch.randn(60, 256, requires_grad=True).cuda()
>>> output = loss(input)
>>> output.backward()
"""
def __init__(self, cfg):
r"""
Parameters
----------
cfg: (cfgNode)
anneal : float
the temperature of the sigmoid that is used to smooth the ranking function
batch_size : int
the batch size being used
num_id : int
the number of different classes that are represented in the batch
feat_dims : int
the dimension of the input feature embeddings
"""
self.anneal = 0.01
self.num_id = cfg.SOLVER.IMS_PER_BATCH // cfg.DATALOADER.NUM_INSTANCE
# self.num_id = 6
def __call__(self, embedding, targets):
"""Forward pass for all input predictions: preds - (batch_size x feat_dims) """
# ------ differentiable ranking of all retrieval set ------
embedding = F.normalize(embedding, dim=1)
feat_dim = embedding.size(1)
# For distributed training, gather all features from different process.
if comm.get_world_size() > 1:
all_embedding = concat_all_gather(embedding)
all_targets = concat_all_gather(targets)
else:
all_embedding = embedding
all_targets = targets
sim_dist = torch.matmul(embedding, all_embedding.t())
N, M = sim_dist.size()
# Compute the mask which ignores the relevance score of the query to itself
mask_indx = 1.0 - torch.eye(M, device=sim_dist.device)
mask_indx = mask_indx.unsqueeze(dim=0).repeat(N, 1, 1) # (N, M, M)
# sim_dist -> N, 1, M -> N, M, N
sim_dist_repeat = sim_dist.unsqueeze(dim=1).repeat(1, M, 1) # (N, M, M)
# sim_dist_repeat_t = sim_dist.t().unsqueeze(dim=1).repeat(1, N, 1) # (N, N, M)
# Compute the difference matrix
sim_diff = sim_dist_repeat - sim_dist_repeat.permute(0, 2, 1) # (N, M, M)
# Pass through the sigmoid
sim_sg = sigmoid(sim_diff, temp=self.anneal) * mask_indx
# Compute all the rankings
sim_all_rk = torch.sum(sim_sg, dim=-1) + 1 # (N, N)
pos_mask = targets.view(N, 1).expand(N, M).eq(all_targets.view(M, 1).expand(M, N).t()).float() # (N, M)
pos_mask_repeat = pos_mask.unsqueeze(1).repeat(1, M, 1) # (N, M, M)
# Compute positive rankings
pos_sim_sg = sim_sg * pos_mask_repeat
sim_pos_rk = torch.sum(pos_sim_sg, dim=-1) + 1 # (N, N)
# sum the values of the Smooth-AP for all instances in the mini-batch
ap = 0
group = N // self.num_id
for ind in range(self.num_id):
pos_divide = torch.sum(
sim_pos_rk[(ind * group):((ind + 1) * group), (ind * group):((ind + 1) * group)] / (sim_all_rk[(ind * group):((ind + 1) * group), (ind * group):((ind + 1) * group)]))
ap += pos_divide / torch.sum(pos_mask[ind*group]) / N
return 1 - ap
class SmoothAP_old(torch.nn.Module):
"""PyTorch implementation of the Smooth-AP loss.
implementation of the Smooth-AP loss. Takes as input the mini-batch of CNN-produced feature embeddings and returns
the value of the Smooth-AP loss. The mini-batch must be formed of a defined number of classes. Each class must
have the same number of instances represented in the mini-batch and must be ordered sequentially by class.
e.g. the labels for a mini-batch with batch size 9, and 3 represented classes (A,B,C) must look like:
labels = ( A, A, A, B, B, B, C, C, C)
(the order of the classes however does not matter)
For each instance in the mini-batch, the loss computes the Smooth-AP when it is used as the query and the rest of the
mini-batch is used as the retrieval set. The positive set is formed of the other instances in the batch from the
same class. The loss returns the average Smooth-AP across all instances in the mini-batch.
Args:
anneal : float
the temperature of the sigmoid that is used to smooth the ranking function. A low value of the temperature
results in a steep sigmoid, that tightly approximates the heaviside step function in the ranking function.
batch_size : int
the batch size being used during training.
num_id : int
the number of different classes that are represented in the batch.
feat_dims : int
the dimension of the input feature embeddings
Shape:
- Input (preds): (batch_size, feat_dims) (must be a cuda torch float tensor)
- Output: scalar
Examples::
>>> loss = SmoothAP(0.01, 60, 6, 256)
>>> input = torch.randn(60, 256, requires_grad=True).cuda()
>>> output = loss(input)
>>> output.backward()
"""
def __init__(self, anneal, batch_size, num_id, feat_dims):
"""
Parameters
----------
anneal : float
the temperature of the sigmoid that is used to smooth the ranking function
batch_size : int
the batch size being used
num_id : int
the number of different classes that are represented in the batch
feat_dims : int
the dimension of the input feature embeddings
"""
super().__init__()
assert(batch_size%num_id==0)
self.anneal = anneal
self.batch_size = batch_size
self.num_id = num_id
self.feat_dims = feat_dims
def forward(self, preds):
"""Forward pass for all input predictions: preds - (batch_size x feat_dims) """
preds = F.normalize(preds, dim=1)
# ------ differentiable ranking of all retrieval set ------
# compute the mask which ignores the relevance score of the query to itself
mask = 1.0 - torch.eye(self.batch_size)
mask = mask.unsqueeze(dim=0).repeat(self.batch_size, 1, 1)
# compute the relevance scores via cosine similarity of the CNN-produced embedding vectors
sim_all = torch.mm(preds, preds.t())
sim_all_repeat = sim_all.unsqueeze(dim=1).repeat(1, self.batch_size, 1)
# compute the difference matrix
sim_diff = sim_all_repeat - sim_all_repeat.permute(0, 2, 1)
# pass through the sigmoid
sim_sg = sigmoid(sim_diff, temp=self.anneal) * mask
# compute the rankings
sim_all_rk = torch.sum(sim_sg, dim=-1) + 1
# ------ differentiable ranking of only positive set in retrieval set ------
# compute the mask which only gives non-zero weights to the positive set
xs = preds.view(self.num_id, int(self.batch_size / self.num_id), self.feat_dims)
pos_mask = 1.0 - torch.eye(int(self.batch_size / self.num_id))
pos_mask = pos_mask.unsqueeze(dim=0).unsqueeze(dim=0).repeat(self.num_id, int(self.batch_size / self.num_id), 1, 1)
# compute the relevance scores
sim_pos = torch.bmm(xs, xs.permute(0, 2, 1))
sim_pos_repeat = sim_pos.unsqueeze(dim=2).repeat(1, 1, int(self.batch_size / self.num_id), 1)
# compute the difference matrix
sim_pos_diff = sim_pos_repeat - sim_pos_repeat.permute(0, 1, 3, 2)
# pass through the sigmoid
sim_pos_sg = sigmoid(sim_pos_diff, temp=self.anneal) * pos_mask
# compute the rankings of the positive set
sim_pos_rk = torch.sum(sim_pos_sg, dim=-1) + 1
# sum the values of the Smooth-AP for all instances in the mini-batch
ap = torch.zeros(1)
group = int(self.batch_size / self.num_id)
for ind in range(self.num_id):
pos_divide = torch.sum(sim_pos_rk[ind] / (sim_all_rk[(ind * group):((ind + 1) * group), (ind * group):((ind + 1) * group)]))
ap = ap + ((pos_divide / group) / self.batch_size)
return 1-ap
if __name__ == '__main__':
loss1 = SmoothAP(0.01)
loss2 = SmoothAP_old(0.01, 60, 6, 256)
inputs = torch.randn(60, 256, requires_grad=True)
targets = []
for i in range(6):
targets.extend([i]*10)
targets = torch.LongTensor(targets)
output1 = loss1(inputs, targets)
output2 = loss2(inputs)
print(torch.sum(output1 - output2))

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@ -7,9 +7,7 @@
import torch
import torch.nn.functional as F
from fastreid.utils import comm
from fastreid.layers import GatherLayer
from .utils import concat_all_gather, euclidean_dist, normalize, cosine_dist
from .utils import euclidean_dist, cosine_dist
def softmax_weights(dist, mask):
@ -38,20 +36,13 @@ def hard_example_mining(dist_mat, is_pos, is_neg):
"""
assert len(dist_mat.size()) == 2
N = dist_mat.size(0)
# `dist_ap` means distance(anchor, positive)
# both `dist_ap` and `relative_p_inds` with shape [N, 1]
dist_ap, relative_p_inds = torch.max(
dist_mat[is_pos].contiguous().view(N, -1), 1, keepdim=True)
# both `dist_ap` and `relative_p_inds` with shape [N]
dist_ap, _ = torch.max(dist_mat * is_pos, dim=1)
# `dist_an` means distance(anchor, negative)
# both `dist_an` and `relative_n_inds` with shape [N, 1]
dist_an, relative_n_inds = torch.min(
dist_mat[is_neg].contiguous().view(N, -1), 1, keepdim=True)
# shape [N]
dist_ap = dist_ap.squeeze(1)
dist_an = dist_an.squeeze(1)
# both `dist_an` and `relative_n_inds` with shape [N]
dist_an, _ = torch.min(dist_mat * is_neg + is_pos * 99999999., dim=1)
return dist_ap, dist_an
@ -68,8 +59,8 @@ def weighted_example_mining(dist_mat, is_pos, is_neg):
"""
assert len(dist_mat.size()) == 2
is_pos = is_pos.float()
is_neg = is_neg.float()
is_pos = is_pos
is_neg = is_neg
dist_ap = dist_mat * is_pos
dist_an = dist_mat * is_neg
@ -91,6 +82,7 @@ def triplet_loss(embedding, targets, margin, norm_feat, hard_mining):
dist_mat = cosine_dist(embedding, embedding)
else:
dist_mat = euclidean_dist(embedding, embedding)
# For distributed training, gather all features from different process.
# if comm.get_world_size() > 1:
# all_embedding = torch.cat(GatherLayer.apply(embedding), dim=0)
@ -100,8 +92,8 @@ def triplet_loss(embedding, targets, margin, norm_feat, hard_mining):
# all_targets = targets
N = dist_mat.size(0)
is_pos = targets.view(N, 1).expand(N, N).eq(targets.view(N, 1).expand(N, N).t())
is_neg = targets.view(N, 1).expand(N, N).ne(targets.view(N, 1).expand(N, N).t())
is_pos = targets.view(N, 1).expand(N, N).eq(targets.view(N, 1).expand(N, N).t()).float()
is_neg = targets.view(N, 1).expand(N, N).ne(targets.view(N, 1).expand(N, N).t()).float()
if hard_mining:
dist_ap, dist_an = hard_example_mining(dist_mat, is_pos, is_neg)

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@ -113,4 +113,12 @@ class Baseline(nn.Module):
self._cfg.MODEL.LOSSES.CIRCLE.GAMMA,
) * self._cfg.MODEL.LOSSES.CIRCLE.SCALE
if "Cosface" in loss_names:
loss_dict["loss_cosface"] = pairwise_cosface(
pred_features,
gt_labels,
self._cfg.MODEL.LOSSES.COSFACE.MARGIN,
self._cfg.MODEL.LOSSES.COSFACE.GAMMA,
) * self._cfg.MODEL.LOSSES.COSFACE.SCALE
return loss_dict